Water hyacinth Nile tilapia Histopathology
Effect of Source and Level of Dietary Water Hyacinth on Nile Tilapia Oreochromis Niloticus- Histopathology
Published: September 7, 2010
By: A.M. Abdelhamid, F. I. Magouz, M. I. B. El-Mezeen, A. E. Abd El-Khalik, M. M. El-Sayed Khlaf Allah, and E. M. O. Ahmed
INTRODUCTION
EL-Sayed (2006) mentioned that Egypt produced 20% of the world tilapia capture and 12% of the world farmed tilapia. Bakeer (2009) cited that tilapia fish are among the ancient Egyptian fish of origin; yet, they became among the most outspreading fish species all over the world. They are cultured nowadays world wide , so their production exceeded than 2.5 million tons year 2006, and Egypt now take the 2nd position after China in the world production and the 1st in Africa and middle East . He added that the local fish production is more than one million ton, from which the fish culture is about 63% (630 thousand tons) year 2007. About 80% of the culture production is tilapia (504 thousand tons). Water hyacinth (Eichhorinia crassipes, Mart Solms) is a warm water aquatic plant which widespread in many countries, particularly during summer months with its highest growth in July (Sivakami and Ayyappan, 1991). To be environmentally friends as well as to overcome the fish culture main problem of aqua feed shortage, an attention may be gifted to use this weed "water hyacinth" in fish feeding. So, the aim of this thesis was to evaluate the possibility of feeding Nile tilapia fish for 12 weeks on graded levels of replacing soybean meal protein with water hyacinth leaves meal protein.
The evaluation was carried out via studying the quality criteria of fish rearing water, growth performance and survival of fish, feed and nutrients utilization, blood picture, chemical composition and economic evaluation.
MATERIALS AND METHODS
An in-door feeding experiment was conducted for 12 weeks to study the effect of replacing soybean meal protein by 0, 10, 20, 30 and 40% water hyacinth (Eichhorinia crassipes) protein from two sources, either from clean water or from polluted water, on growth performance, feed utilization, body composition, some blood parameters and preliminary economical evaluation of Nile tilapia (Oreochromis niloticus) fingerlings breeding.
Source of water hyacinth:
Water hyacinth was collected from two sources, the first source was from clean water (chanel) of the River Nile at Kafr El-Zayat city. The second source was from polluted water (ditch) collected from a canal at Tanta city, Manshiet Ganzor. The roots were removed and the rest of the plants were washed with rumming tap water to minimize the soil contamination, then dried under sunlight, and stored at room temperature until be used.
Experimaental fish:
The experimental fish (Oreochromis niloticus) were taken from the stock of Fish Research Laboratory in the Animal Production Department, Faculty of Agriculture, Kafrelsheikh University during January 2005. Prior to the start of the experiment, the fingerlings were placed in a fiberglass tank and randomly distributed into the experimental aquaria to be adapted to the experimental conditions until the starting of the experiment. Fish were fed a control diet (without water hyacinth) for two weeks at a feeding level of 3% from the body biomass; during this period, healthy fish at the same weight replaced the died ones.
Experimental design of rearing fish:
A total number of 360 fish with 12.4 g average initial body weight were randomly distributed into 30 glass aquaria (70 l each, 12 fish in each). Each treatment was represented in three aquaria. Fresh tap water was stored in fiberglass tanks for 24h under aeration for dechlorination. One third of water aquaria was replaced daily and totally once every week after removing the wastes. The experimental aquaria were supplied with air by electerical small pumps and air stones. During the experimental period (12 weeks), each aquarium was suppled with electric heater and the water temperature was maintained on 26?10C through the thermostat. Photoperiod was controlled to be 14h per day using florescent light. Fish feces and feed residue were removed daily by siphoning. Water pH was in the range of 7.15-7.20 during the experimental period.
Experimental diets and feeding regime:
Prior to the start of the experiment, the fishes were adapted to a basal control diet (T1) containing about 26% crude protein and consisted of fish meal, soybean meal, yellow corn, wheat bran, sunflower oil and vitamin and minerals mixture for two weeks. Ten experimental diets were formulated from a basal diet to contain two sources of dried water hyacinth at a level of 0, 10, 20, 30 and 40% of soybean meal protein (diets No. 1, 2, 3, 4 and 5), respectively (from unpolluted water) and 0, 10, 20, 30 and 40% of soybean meal protein (diets No. 6, 7, 8, 9 and 10), respectively (from polluted water). A basal diet was made from the commercial ingredients. The dry ingredients were finely grounded and mixed by a dough mixer for 20 minutes for homogeneity. Oil was gradually added during the mixing. After homogenous mixture was obtained, forty ml water per hundred g diet was slowly added to the mixture. The diets were cooked on a water evaporator for 20 minutes. The diets were pelleted (3 mm) through fodder machine and the manufacture pellets were dried in a drying oven at 70oC for 48 hours. The diets were collected, tagged and stored in refrigerator at 4oC. Fish in all treatments were daily fed the experimental diets at a level of 3% of the fish biomass then weighed every week; accordingly, the amount of food (which was given at two times daily at 8.0 a.m. and 3.0 p.m., six days a week for 12 weeks) was recalculated.
Histological examination:
At the end of the experiment, fish were sacrificed and the target organs (gonads) were sampled. Samples were fixed in 10% neutralized formalin solution followed by washing with tab water, then dehydrated by different grades of alcohol (70, 85, 96 and 99%). Samples were cleared by xylene and embedded in paraffin wax. The wax blocks were sectioned to six micron. The sections were stained by hematoxyline (H) and eosin (E) and then subjected to a histological examination according to Pearse (1968) and Roberts (2004).
RESULTS AND DISCUSSION
Histological examination of liver:
The histological examination of liver of fishes in experimental treatments revealed that liver of fish fed on the control diet without water hyacinth (D1) showed normal architecture of the hepatic lobules, normal central vein and blood sinusoid with regular arrangement of the hepatocytes within each hepatic lobule (Plate 1). Such finding indicated absence of any pathological effects on liver function of the control fish. Feeding fish on diets containing 10 or 20% water hyacinth from clean source (D2 and D3, respectively) showed intact architecture of the hepatic and portal lobules with slight effects on the liver, which did not develop to be pathologically affecting the liver function of fishes fed D2 and D3. In some individuals fed D3, the liver showed intact hepatic lobular architecture with slight effects on the hepatic central vein and hepatocytes. Within the hepatic lobules, the central vein was enlarged and had slight branching with mild infiltiration of monocytes, and the hepatocytes had small vacuoles (Plate 2). It is of interest to observe that increasing the percentage of replacement with water hyacinth from clean source more than 20% in the diet of fish resulted in some lesions in the liver, which considered as pathological effects leading to some liver dysfunction (Plate 3). These effects seemed to be maximized by increasing level of water hyacinth up to 40% in dits of fishes. In liver of fish fed diet (D3) containing 20% water hyacinth from clean source, slight effects were found in the hepatic central vein and hepatocytes. Within the hepatic lobules, the central vein was enlarged and had slight branching with mild infiltiration of monocytes, and the hepatocytes had small vacuoles (Plate 2). However, liver of fish fed diet (D4) containing 30% water hyacinth from clean source showed monocytes aggregation and mild necrosis of the hepatocytes within the hepatic lobules. Also, small vacuoles were found within the hepatic lobules (Plate 3).
EL-Sayed (2006) mentioned that Egypt produced 20% of the world tilapia capture and 12% of the world farmed tilapia. Bakeer (2009) cited that tilapia fish are among the ancient Egyptian fish of origin; yet, they became among the most outspreading fish species all over the world. They are cultured nowadays world wide , so their production exceeded than 2.5 million tons year 2006, and Egypt now take the 2nd position after China in the world production and the 1st in Africa and middle East . He added that the local fish production is more than one million ton, from which the fish culture is about 63% (630 thousand tons) year 2007. About 80% of the culture production is tilapia (504 thousand tons). Water hyacinth (Eichhorinia crassipes, Mart Solms) is a warm water aquatic plant which widespread in many countries, particularly during summer months with its highest growth in July (Sivakami and Ayyappan, 1991). To be environmentally friends as well as to overcome the fish culture main problem of aqua feed shortage, an attention may be gifted to use this weed "water hyacinth" in fish feeding. So, the aim of this thesis was to evaluate the possibility of feeding Nile tilapia fish for 12 weeks on graded levels of replacing soybean meal protein with water hyacinth leaves meal protein.
The evaluation was carried out via studying the quality criteria of fish rearing water, growth performance and survival of fish, feed and nutrients utilization, blood picture, chemical composition and economic evaluation.
MATERIALS AND METHODS
An in-door feeding experiment was conducted for 12 weeks to study the effect of replacing soybean meal protein by 0, 10, 20, 30 and 40% water hyacinth (Eichhorinia crassipes) protein from two sources, either from clean water or from polluted water, on growth performance, feed utilization, body composition, some blood parameters and preliminary economical evaluation of Nile tilapia (Oreochromis niloticus) fingerlings breeding.
Source of water hyacinth:
Water hyacinth was collected from two sources, the first source was from clean water (chanel) of the River Nile at Kafr El-Zayat city. The second source was from polluted water (ditch) collected from a canal at Tanta city, Manshiet Ganzor. The roots were removed and the rest of the plants were washed with rumming tap water to minimize the soil contamination, then dried under sunlight, and stored at room temperature until be used.
Experimaental fish:
The experimental fish (Oreochromis niloticus) were taken from the stock of Fish Research Laboratory in the Animal Production Department, Faculty of Agriculture, Kafrelsheikh University during January 2005. Prior to the start of the experiment, the fingerlings were placed in a fiberglass tank and randomly distributed into the experimental aquaria to be adapted to the experimental conditions until the starting of the experiment. Fish were fed a control diet (without water hyacinth) for two weeks at a feeding level of 3% from the body biomass; during this period, healthy fish at the same weight replaced the died ones.
Experimental design of rearing fish:
A total number of 360 fish with 12.4 g average initial body weight were randomly distributed into 30 glass aquaria (70 l each, 12 fish in each). Each treatment was represented in three aquaria. Fresh tap water was stored in fiberglass tanks for 24h under aeration for dechlorination. One third of water aquaria was replaced daily and totally once every week after removing the wastes. The experimental aquaria were supplied with air by electerical small pumps and air stones. During the experimental period (12 weeks), each aquarium was suppled with electric heater and the water temperature was maintained on 26?10C through the thermostat. Photoperiod was controlled to be 14h per day using florescent light. Fish feces and feed residue were removed daily by siphoning. Water pH was in the range of 7.15-7.20 during the experimental period.
Experimental diets and feeding regime:
Prior to the start of the experiment, the fishes were adapted to a basal control diet (T1) containing about 26% crude protein and consisted of fish meal, soybean meal, yellow corn, wheat bran, sunflower oil and vitamin and minerals mixture for two weeks. Ten experimental diets were formulated from a basal diet to contain two sources of dried water hyacinth at a level of 0, 10, 20, 30 and 40% of soybean meal protein (diets No. 1, 2, 3, 4 and 5), respectively (from unpolluted water) and 0, 10, 20, 30 and 40% of soybean meal protein (diets No. 6, 7, 8, 9 and 10), respectively (from polluted water). A basal diet was made from the commercial ingredients. The dry ingredients were finely grounded and mixed by a dough mixer for 20 minutes for homogeneity. Oil was gradually added during the mixing. After homogenous mixture was obtained, forty ml water per hundred g diet was slowly added to the mixture. The diets were cooked on a water evaporator for 20 minutes. The diets were pelleted (3 mm) through fodder machine and the manufacture pellets were dried in a drying oven at 70oC for 48 hours. The diets were collected, tagged and stored in refrigerator at 4oC. Fish in all treatments were daily fed the experimental diets at a level of 3% of the fish biomass then weighed every week; accordingly, the amount of food (which was given at two times daily at 8.0 a.m. and 3.0 p.m., six days a week for 12 weeks) was recalculated.
Histological examination:
At the end of the experiment, fish were sacrificed and the target organs (gonads) were sampled. Samples were fixed in 10% neutralized formalin solution followed by washing with tab water, then dehydrated by different grades of alcohol (70, 85, 96 and 99%). Samples were cleared by xylene and embedded in paraffin wax. The wax blocks were sectioned to six micron. The sections were stained by hematoxyline (H) and eosin (E) and then subjected to a histological examination according to Pearse (1968) and Roberts (2004).
RESULTS AND DISCUSSION
Histological examination of liver:
The histological examination of liver of fishes in experimental treatments revealed that liver of fish fed on the control diet without water hyacinth (D1) showed normal architecture of the hepatic lobules, normal central vein and blood sinusoid with regular arrangement of the hepatocytes within each hepatic lobule (Plate 1). Such finding indicated absence of any pathological effects on liver function of the control fish. Feeding fish on diets containing 10 or 20% water hyacinth from clean source (D2 and D3, respectively) showed intact architecture of the hepatic and portal lobules with slight effects on the liver, which did not develop to be pathologically affecting the liver function of fishes fed D2 and D3. In some individuals fed D3, the liver showed intact hepatic lobular architecture with slight effects on the hepatic central vein and hepatocytes. Within the hepatic lobules, the central vein was enlarged and had slight branching with mild infiltiration of monocytes, and the hepatocytes had small vacuoles (Plate 2). It is of interest to observe that increasing the percentage of replacement with water hyacinth from clean source more than 20% in the diet of fish resulted in some lesions in the liver, which considered as pathological effects leading to some liver dysfunction (Plate 3). These effects seemed to be maximized by increasing level of water hyacinth up to 40% in dits of fishes. In liver of fish fed diet (D3) containing 20% water hyacinth from clean source, slight effects were found in the hepatic central vein and hepatocytes. Within the hepatic lobules, the central vein was enlarged and had slight branching with mild infiltiration of monocytes, and the hepatocytes had small vacuoles (Plate 2). However, liver of fish fed diet (D4) containing 30% water hyacinth from clean source showed monocytes aggregation and mild necrosis of the hepatocytes within the hepatic lobules. Also, small vacuoles were found within the hepatic lobules (Plate 3).
Plate (1): Section in liver of fish fed the control diet (clean source) (D1) showing normal architecture of the hepatic lobules, normal central vein and blood sinusoid (x 80; H & E stains).
Plate (2): Section in liver of fish fed diet (D3) containing 20% water hyacinth from clean source showing slight effects on the hepatic central vein and hepatocytes. Within the hepatic lobules, the central vein was enlarged and had slight branching with mild infiltiration of monocytes, and the hepatocytes had small vacuoles (x 80, H & E stains).
Plate (3): Section in liver of fish fed diet (D4) containing 30% water hyacinth from clean source showing monocytes aggregation and mild necrosis of the hepatocytes within the hepatic lobules. Also, small vacuoles were found within the hepatic lobules (x 80; H & E stains).
It is worthy noting that the pronounced pathological effects in liver of fishes were discovered when dietary supplementation of water hyacinth from clean source increased to 30 and 40% in D4 and D5, respectively. The liver of fish fed diet (D4) containing 30% water hyacinth (clean source) showed abnormal hepatic portal lobules as well as widened area and thickened wall of the portal tracts (Plate 4). Similar lesions were observed in liver of fish fed diet (D5) containing 40% water hyacinth (clean source), in which all vessels (lemphatic and bile tracts) within the portal lobules were widened and branched (Plate 5). Such findings indicated harmful effects of feeding diets containing 30 or 40% water hyacinth from clean source as replacement of soybean meal protein on liver function of O. niloticus fish. The harmful effect of the higher level of water hyacinth from clean source may be related to the chemical composition of water hyacinth.
It is worthy noting that results of the histological study were associated with those obtained regard to measurements of growth performance and feed utilization parameters, hepatic somatic index, blood serum parameters (total protein, albumin and globulin concentrations) and activity of transaminases in blood serum. Concerning the effect of diets containing different levels of water hyacinth on livel, the histological examination of liver of fish fed the control diet (D6, polluted source) revealed intact architecture of the hepatic lobules in term of normal central hepatic vein, normal arrangement of hepatocytes and regular blood sinusoids. These results are similar to those obtained in liver of fish fed the control diet (D1, clean source).
It is worthy noting that results of the histological study were associated with those obtained regard to measurements of growth performance and feed utilization parameters, hepatic somatic index, blood serum parameters (total protein, albumin and globulin concentrations) and activity of transaminases in blood serum. Concerning the effect of diets containing different levels of water hyacinth on livel, the histological examination of liver of fish fed the control diet (D6, polluted source) revealed intact architecture of the hepatic lobules in term of normal central hepatic vein, normal arrangement of hepatocytes and regular blood sinusoids. These results are similar to those obtained in liver of fish fed the control diet (D1, clean source).
Plate (4): Section in liver of fish fed diet (D4) containing 30% water hyacinth from clean source showing abnormal hepatic portal lobules as well as widened area and thickened wall of the portal tracts (x 200; H & E stains).
Plate (5): Section in liver of fish fed diet (D5) containing 40% water hyacinth from clean source showing widening and branching the vessels in the portal lobules including lemphatic and bile tracts (x 100; H & E stains).
On the other hand, feeding fish on diet (D7) containing 10% water hyacinth from polluted source resulted in slight lesions in the histological structure in the liver in terms of irregularity in the hepatocytes with mild necrosis, slight infiltration within the central hepatic vein and small widening of blood sinusoids, higher infiltration of monocytes within the central hepatic vein and slight necrosis in hepatocytes scattered around the hepatic central vein (Plate 6). Moreover, slight congestion and necrosis in a plate of hepatocytes as well as abnormal arrangement of hepatocytes were seen within the hepatic lobules (Plate 7). Increasing level of water hyacinth from polluted source in the diet to 20% (D8) led to normal architecture of the hepatic lobule with some abnormality in the portal lobules involving thickned wall of lemphatic tract and bile duct in some individuals (Plate 8). Also, in liver of other individuals fed diet (D8) containing 20% water hyacinth from polluted source, small collection and slight infiltration of monocytes between the hepatocytes were found within the hepatic lobule (Plate 9). The pathological effects in liver was more pronounced when level of water hyacinth from polluted source in the diet was increased to 30 or 40% in D9 and D10, respectively. Liver of fish fed diet (D9) containing 30% water hyacinth from polluted source) showed widening and branch the vessels in the portal lobules including lemphatic and bile tracts (Plate 10).
However, in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source, large areas of degeneration and disconnection between hepatocytes were seen within the hepatic lobules (Plate 11), widening and congestion of the portal area and mild infiltration of monocytes within the portal tracts (Plate 12), and great dilatation of the blood sinusoids within most of the hepatic lobules (Plate 13). These finding in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source indicated sever and chorionic effects of the highest level of water hyacinth from polluted source, which were mainly related to the chemical composition of polluted water hyacinth. In general, there were individual variations in level of severity of these lesions in the liver, which may be attributed to live body weight and the physiological status of the fishes (Abdelhamid et al., 2002-c). Generally, the obtained findings of the histological examination indicated the beneficial effects of replacement of soybean meal protein by 20% of water hyacinth from clean sources or by 10% of water hyacinth from polluted sources. It is of interest to note that most lesions were found in hepatocytes and with lower extent in the portal region. Kandil et al. (1991) and Abdelhamid et al. (2002-a) explained that hepatocytes are the first targets to the aflatoxins, as they were affected by the toxin when the blood passes firstly through them. These finding in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source indicated sever and chorionic effects of the highest level of water hyacinth from polluted source, which were mainly related to the chemical composition of polluted water hyacinth. In general, there were individual variations in level of severity of these lesions in the liver, which may be attributed to live body weight and the physiological status of the fishes (Abdelhamid et al., 2002-c and 2010).
However, in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source, large areas of degeneration and disconnection between hepatocytes were seen within the hepatic lobules (Plate 11), widening and congestion of the portal area and mild infiltration of monocytes within the portal tracts (Plate 12), and great dilatation of the blood sinusoids within most of the hepatic lobules (Plate 13). These finding in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source indicated sever and chorionic effects of the highest level of water hyacinth from polluted source, which were mainly related to the chemical composition of polluted water hyacinth. In general, there were individual variations in level of severity of these lesions in the liver, which may be attributed to live body weight and the physiological status of the fishes (Abdelhamid et al., 2002-c). Generally, the obtained findings of the histological examination indicated the beneficial effects of replacement of soybean meal protein by 20% of water hyacinth from clean sources or by 10% of water hyacinth from polluted sources. It is of interest to note that most lesions were found in hepatocytes and with lower extent in the portal region. Kandil et al. (1991) and Abdelhamid et al. (2002-a) explained that hepatocytes are the first targets to the aflatoxins, as they were affected by the toxin when the blood passes firstly through them. These finding in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source indicated sever and chorionic effects of the highest level of water hyacinth from polluted source, which were mainly related to the chemical composition of polluted water hyacinth. In general, there were individual variations in level of severity of these lesions in the liver, which may be attributed to live body weight and the physiological status of the fishes (Abdelhamid et al., 2002-c and 2010).
Plate (6): Section in liver of fish fed diet (D7) containing 10% water hyacinth from polluted source showing irregularity in the hepatocytes with mild necrosis, slight infiltration within the central hepatic vein and small widening of blood sinusoids, higher infiltration of monocytes within the central hepatic vein and slight necrosis in hepatocytes scattered around the hepatic central vein (x 80; H & E stain).
Plate (7): Section in liver of fish fed (D7) containing 10% water hyacinth from polluted source showing slight congestion and necrosis in a plate of hepatocytes. Also, abnormal arrangement of hepatocytes is seen within the hepatic lobules (x 100; H & E stain).
Plate (8): Section in liver of fish fed diet (D8) containing 20% water hyacinth from polluted source showing normal architecture of the hepatic lobule with some abnormality in the portal lobules involving thickned wall of lemphatic tract and bile duct (x 80; H & E stain).
Plate (9): Section in liver of fish fed diet (D8) containing 20% water hyacinth from polluted source showing small collection and slight infiltration of monocytes between the hepatocytes within the hepatic lobule (x 80; H & E stain).
Plate (10): Section in liver of fish fed diet (D9) containing 30% water hyacinth from polluted source showing widening and branching the vessels in the portal lobules including lemphatic and bile tracts (x 100; H & E stain).
Plate (11): Section in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source showing large areas of degeneration and disconnection between hepatocytes (x 80; H & E stain).
Plate (12): Section in liver of fish fed diet (D10) containing 40% water hyacinth from polluted source showing high widening and congestion of the portal area and mild infiltration of monocytes within the portal tracts (x 80; H & E stain).
Kidney
The histological examination of the kidney of fish fed on the control diet (clean source (D1) showed normal architecture of the renal cortex with Malpigian corpuscles containing normal glomeruli and Bowman's capsules. Also, the renal cortex had normal proximal and distal renal tubules (Plate 14). The renal medulla contained normal small, medium and large renal tubules, all were characterized by a single layer of cuboidal epithelial cells. Addition of 10% water hyacinth from clean source in diet of fish (D2) did not affect the normal architecture of the renal cortex. It contained intact glomeruli within Malpigian corpuscles, but slight enlargement was seen in some proximal renal tubules (Plate 15). Increasing the inclusion of water hyacinth from clean source in diet of fish to 20% (D3) also did not affect the normal architecture of the renal cortex with slight lesions in glomeruli within Malpigian corpuscles, and slight enlargement in some proximal renal tubules (Plate 16).
Plate (14): Section in kidney of fish fed control diet (clean source) (D1) showing normal architecture of the renal cortex with Malpigian corpuscles containing normal glomeruli and Bowman's capsule. Also, normal proximal and distal renal tubules are seen (H & E stains x 200).
Plate (15): Section in kidney of fish fed diet (D2) containing 10% water hyacinth from clean source showing normal architecture of the renal cortex with intact glomerulosa within Malpigian corpuscles, but slight enlargement was seen in some proximal renal tubules (H & E stains x 200).
Plate (16): Section in kidney of fish fed diet (D3) containing 20% water hyacinth from clean source showing normal architecture of the renal cortex with slight lisions in glomeruli within Malpigian corpuscles, and slight enlargement was seen in some proximal renal tubules (H & E stains x 200).
Such findings may indicate the save usage of water hyacinth from clean source in diet of fish up to 20% without pronounced pathological effects. Only slight effects on the intact glomeruli and normal proximal and distal renal tubules were seen within the renal cortex. These results indicated that adding 10 or 20% of water hyacinth from clean source in the control diet of fish did not adversely affect the normal histogenesis of the kidney. When fish were fed on diet (D4) containing 30% water hyacinth from clean source the renal cortex showed sever congestion of glomeruli and dilitdation in some proximal and distal renal tubules (Plate 17). On the other hand, increasing the level of water hyacinth from clean source up to 40% (D5), kidneys of some fishes showed sever congestion of glomeruli and high infiltration of fibroblast cells within and between the renal tubules (Plate 18). Regarding the effect of inclusion water hyacinth from polluted source with different levels on the histological structure of fish kidneys, the histological examination revealed kidney of fish fed the control diet (polluted source, D6) showed normal architecture of the renal cortex with Malpigian corpuscles containing normal glomeruli and Bowman's capsule, and also normal proximal and distal renal tubules (Plate 19). The renal medulla contained normal small, medium and large renal tubules, all were characterized by a single layer of cuboidal epithelial cells (Plate 20).
Plate (17): Section in kidney of fish fed diet (D4) containing 30% water hyacinth from clean source showing renal cortex sever congestion of glomerulosa and dilitdation in some proximal and distal renal tubules (x 200, H & E stains).
Plate (18): Section in kidney of fish fed diet (D5) containing 40% water hyacinth from clean source showing sever congestion of glomerulosa and high infiltration of fibroblast cells within and between the renal tubules (x 200, H & E stains).
Plate (19): Section in kidney of fish fed the control diet (D6) (polluted source) showing normal architecture of the renal cortex with Malpigian corpuscles containing normal glomerulosa and Bowman's capsule. Also, normal proximal and distal renal tubules are seen (H & E stains x 200).
Plate (20): Section in kidney of fish fed the control diet (D6) (polluted source) showing renal medulla containing normal small, medium and large renal tubules, all were characterized by a single layer of cuboidal epithelial cells (H & E stains x 200).
The histological examination of kidney of fish fed diet (D7) containing 10% water hyacinth from polluted source showed normal architecture of the renal cortex. However, increasing level of water hyacinth from polluted source to 20% in diet of fish (D8) caused the renal cortex with less intact glomeruli and renal tubules. Slight congesion in glomeruli and atrophy of some renal tubules were seen in the renal cortex of fis fed diet containing 20% water hyacinth from polluted source (Plate 21). It is worthy noting that the histological examination of kidney of fish fed diet (D8) containing 20% water hyacinth from polluted source showed renal medulla with renal tubules with small diameter linning with a single layer of epithelial cells containing pronounced large vacules (Plate 22).
According to the histological examination of fish kidney fed 10 and 20% water hyacinth from polluted source, the optimal level of inclusion water hyacinth from polluted source in diets of fish seemed to be only 10%, whereas some pathological effects are apparently seen in kidney of fish fed 20% water hyacinth from polluted source. Such findings may indicate benefits of feeding fish on diet in which soybean meal protein was replaced by 10% water hyacinth from polluted source without any pathological effects on kidney function. On the same time, increasing water hyacinth from polluted source in diet of fish to 30% led sever and chrionoc lesions in fish kidney. In these cases degeneration of Malpigian corpuscles and enalrgement in the proximal and distal tubules were found in the renal cortex. Also, sever consion in glomeruli of some Malpigian corpuscles were seen (Plate 23). Interestingly to observe that the highest replacement of soybean meal protein by 40% water hyacinth from polluted source showing caused destruction in glomeruli and Bowman's capsules and degeneration of most proximal and distal renal tubules within the renal cortex. Also, there was a degeneration of the epithelial cells lining the renal tubules. Also, the adjacent renal tubules were degenerated with interstitial hemorrhage of blood vessels (Plate 24).
According to the histological examination of fish kidney fed 10 and 20% water hyacinth from polluted source, the optimal level of inclusion water hyacinth from polluted source in diets of fish seemed to be only 10%, whereas some pathological effects are apparently seen in kidney of fish fed 20% water hyacinth from polluted source. Such findings may indicate benefits of feeding fish on diet in which soybean meal protein was replaced by 10% water hyacinth from polluted source without any pathological effects on kidney function. On the same time, increasing water hyacinth from polluted source in diet of fish to 30% led sever and chrionoc lesions in fish kidney. In these cases degeneration of Malpigian corpuscles and enalrgement in the proximal and distal tubules were found in the renal cortex. Also, sever consion in glomeruli of some Malpigian corpuscles were seen (Plate 23). Interestingly to observe that the highest replacement of soybean meal protein by 40% water hyacinth from polluted source showing caused destruction in glomeruli and Bowman's capsules and degeneration of most proximal and distal renal tubules within the renal cortex. Also, there was a degeneration of the epithelial cells lining the renal tubules. Also, the adjacent renal tubules were degenerated with interstitial hemorrhage of blood vessels (Plate 24).
Plate (21): Section in kidney of fish fed diet (D8) containing 20% water hyacinth from polluted source showing renal cortex without intact glomerulosa and renal tubules. Congesion in glomerulosa and atrophy of some renal tubules are seen (x 200, H & E stains).
Plate (22): Section in kidney of fish fed diet (D8) containing 20% water hyacinth from polluted source showing renal medulla with small renal tubules having a single layer of epithelial cells containing large vacules (x 150, H & E stain).
Plate (23): Section in kidney of fish fed diet (D9) containing 30% water hyacinth from polluted source showing degeneration of Malpigian corpuscles and enalrgement in the proximal and distal tubules. Also, sever consion in glomeruli of some Malpigian corpuscles were seen (x 150, H & E stain).
Plate (24): Section in kidney of fish fed diet (D10) containing 40% water hyacinth from polluted source showing renal cortex with destructive glomerulosa and Bowman's capsules and degeneration of most proximal and distal renal tubules. Also, there was a degeneration of the epithelial cells lining the renal tubules (x 200, H & E stain).
It is of interest to note that the pathological changes in the normal architecture of the kidney were associated with those observed in the liver of fish fed different diets containing different levels of water hyacinth from clean or polluted sources, but some histological changes in the kidney and liver of fish fed higher level of water hyacinth from clean sources were attributed to the dietary replacement especially to level of water hyacinth, which contained high level of minerals. However, the pathological changes in the kidney and liver of fish fed different levels of water hyacinth from polluted sources, except that at 10% water hyacinth, were in relation with increasing level of heavy metal contents in water hyacinth from polluted source.
The present pathological signs of diets containing more than 20% of water hyacinth from clean source or more than 10% water hyacinth from polluted source were similar to that obtained by Abdelhamid et al. (2002-b & c) and Soliman et al. (2000) on fish fed aflatoxines. These results indicated that replacing soybean meal protein water hyacinth from clean source up to 20% or replacing soybean meal protein only by 10% water hyacinth from polluted source in the control diet of fish did not adversely affect the normal histogenesis and function of the kidney.
The present pathological signs of diets containing more than 20% of water hyacinth from clean source or more than 10% water hyacinth from polluted source were similar to that obtained by Abdelhamid et al. (2002-b & c) and Soliman et al. (2000) on fish fed aflatoxines. These results indicated that replacing soybean meal protein water hyacinth from clean source up to 20% or replacing soybean meal protein only by 10% water hyacinth from polluted source in the control diet of fish did not adversely affect the normal histogenesis and function of the kidney.
Gills:
The histological examination of fish fed the control diet (D1, clean source) showed intact lamellar architecture of the gills in term of normal arrangement and structure of small and large leminae (Plate 25). Also, the external surface of the largest laminae was composed of normal stratified squamous epithelial cells, lamina propria and respiratory bronchioles and normal distribution of goblet cells between the epithelial layer lining boarders of the lamellae.
The histological examination of fish fed the control diet (D1, clean source) showed intact lamellar architecture of the gills in term of normal arrangement and structure of small and large leminae (Plate 25). Also, the external surface of the largest laminae was composed of normal stratified squamous epithelial cells, lamina propria and respiratory bronchioles and normal distribution of goblet cells between the epithelial layer lining boarders of the lamellae.
Plate (25): Section in gills of fish fed the control diet (D1) (clean source) showing normal arrangement and structure of small and large leminae of gills (H & E stains x 80).
Feeding fish on diet containing 10% water hyacinth from clean source (D2) did not show any pathological changes in gills, in which normal arrangement and structure of small and large leminae were seen. In gills of fish fed diet (D3) containing 20% water hyacinth from clean source showing small thickness of large laminae with normal stratified squamous epithelial cells. Also, normal distribution of goblet cells was observed within the epithelial layer lining the lamellae. In contrast to the histological examination of liver and kidney, feeding fish fed diet (D4) containing 30% water hyacinth from clean source showed small thickness of large laminae with normal stratified squamous epithelial cells without pronounced pathological effects on the peripheral boarders of the lamellae, which were lining with normal epithelial cells (Plate 26). Also, in gills of fish fed diet containing 40% water hyacinth from clean source (D5) there was a normal architucture of lamillae in term of normal peripheral boarders lining normal epithelial cells. Concerning the effect of replacing soybean meal protein by different levels of water hyacinth from polluted source, no pathological effects were found in gills of fish fed the control diet (D6) (polluted source). Gills showed normal arrangement and structure of leminae. However, in gills of fish fed diet (D7) containing 10% water hyacinth from polluted source showed serated borders of the lamillae reflecting high distribution of Goblet cells within the epithelial cells, which may consider as signs of resistance or tolerance of fish (Plate 27).
Plate (26): Section in gills of fish fed diet (D4) containing 30% water hyacinth from clean source showing small thickness of large laminae with normal stratified squamous epithelial cells (H & E stains x 80).
Plate (27): Section in gills of fish fed diet (D7) containing 10% water hyacinth from polluted source showing serated borders of the lamillae and distribution of Goblet cells within the epithelial cells (H & E stains x 150).
The hidtological examination of gills in fish fed diet (D8) containing 20% water hyacinth from polluted source showed slight congested lamellae and hyperplasia of the lining epithelial layer of the secondary lamella, desquamation of the epithelial layer and congestion of blood vessels (Plate 28). These effects increased when fish were fed diet (D9) containing 30% water hyacinth from polluted source. Gills showed degeneration of the epithelial layer lining the end of lamellae. Also there are severe congestion and hemorrhage of the lamellae and mild hyperplasia of the secondary lamellae. Furthermore, there was found marked destruction of the lamellae architecture and degenerated epithelial layer lining the lamellae (Plate 29). Fish fed diet (D10) containing 40% water hyacinth from polluted source showed similar changes as found in those fed D9 beside severe lesions in term of obliteration of normal lamellar architecture. Lamellae are nearly within normal with slight inflammentation within filament interstitium (Plate 29). Based on the foregoing findings, the pathological effects on the histological structure of gills appeared when fish were fed on diet containing 30 or 40% water hyacinth from polluted source. Such finding may suggest that gills were more resistant to feeding water polluted water hyacinth as compared to liver and kidney. This was associated with the healthy status of fish which may be attributed to growth performance and blood parameters of fish fed 30 or 40% polluted hyacinth.
Plate (28): Section in gills of fish fed diet (D8) containing 20% water hyacinth from polluted source showing congested lamellae and hyperplasia of the lining epithelial layer of the secondary lamella, desquamation of the epithelial layer and congestion of blood vessels (H & E stains x 100).
Plate (29): Section in gills of fish fed diet (D9) containing 30% water hyacinth from polluted source showing degeneration of the epithelial layer lining the end of lamellae. Severe congestion and hemorrhage of the lamellae and mild hyperplasia of the secondary lamellae. Marked destruction of the lamellae architecture and degenerated epithelial layer lining the lamellae (H & E stains x 100).
Generally, inclusion of higher levels of water hyacinth from clean or polluted sources showed marked lesions in all organs studied (liver, kidney and gills). The mechanism that occurred to cause these lesions is not clearly understood, but these effects may be related to enzyme activity in the liver. In this respect, Boonyaratpalin et al. (2001) found pathological changes in the liver were associated with higher activity of alkaline phosphates as affected by aflatoxins.
Dorsal muscles:
The histological examination of the dorsal muscle of fish fed different levels of water hyacinth from clean or polluted sources did not show any pathological effects on the histological structure of the dorsal muscles. However, the marked differences were seen in diameter and density of the fiber bundles as well as in surface area of the connective tissue between these bundles. The dorsal muscle of fish fed control diet (clean source) (D1) showed normal histological structure of fiber bundles and interstitial connective tissue (stroma) between bundles (Plate 30). Also, fish fed diet (D2) containing 10% water hyacinth from clean source indicated normal histological structure with thicker and low density of fiber bundles/unit area and small interstitial connective tissue (stroma) between bundles. In dorsal muscle of fish fed diet (D3) containing 20% water hyacinth from clean source, there was normal histological structure with large diameter fiber bundles and regular thin interstitial connective tissue (stroma) between bundles. In fish fed diet (D4) containing 30% water hyacinth from clean source, the dorsal muscle contained abnormal arrangement of muscle bundles, muscle bundles with large diameter and low density. While large area of the interstitial connective tissue was found between fiber bundles (Plate 31). The dorsal muscle of fish fed diet (D5) containing 40% water hyacinth from clean source showed normal histological structure with large diameter fiber bundles and thin or thick interstitial connective tissue (stroma) between bundles (Plate 32). In the dorsal muscle of fish fed control diet (polluted source) (D6), normal histological structure of fiber bundles and interstitial connective tissue between bundles (stroma) were found.
Dorsal muscles:
The histological examination of the dorsal muscle of fish fed different levels of water hyacinth from clean or polluted sources did not show any pathological effects on the histological structure of the dorsal muscles. However, the marked differences were seen in diameter and density of the fiber bundles as well as in surface area of the connective tissue between these bundles. The dorsal muscle of fish fed control diet (clean source) (D1) showed normal histological structure of fiber bundles and interstitial connective tissue (stroma) between bundles (Plate 30). Also, fish fed diet (D2) containing 10% water hyacinth from clean source indicated normal histological structure with thicker and low density of fiber bundles/unit area and small interstitial connective tissue (stroma) between bundles. In dorsal muscle of fish fed diet (D3) containing 20% water hyacinth from clean source, there was normal histological structure with large diameter fiber bundles and regular thin interstitial connective tissue (stroma) between bundles. In fish fed diet (D4) containing 30% water hyacinth from clean source, the dorsal muscle contained abnormal arrangement of muscle bundles, muscle bundles with large diameter and low density. While large area of the interstitial connective tissue was found between fiber bundles (Plate 31). The dorsal muscle of fish fed diet (D5) containing 40% water hyacinth from clean source showed normal histological structure with large diameter fiber bundles and thin or thick interstitial connective tissue (stroma) between bundles (Plate 32). In the dorsal muscle of fish fed control diet (polluted source) (D6), normal histological structure of fiber bundles and interstitial connective tissue between bundles (stroma) were found.
Plate (30): Section in the dorsal muscle of fish fed control diet (clean source) (D1) showing normal histological structure of fiber bundles and interstitial connective tissue between bundles (stroma) (H & E stains x 80).
Plate (31): Section in dorsal muscle of fish fed diet (D4) containing 30% water hyacinth from clean source showing abnormal arrngement of muscle bundles, Muscle bundles with large diameter and low density. While large area of the interstitial connective tissue was found between fiber bundles (H & E stains x 100).
Plate (32): Section in dorsal muscle of fish fed diet (D5) containing 40% water hyacinth from clean source showing normal histological structure with large diameter fiber bundles and thin or thick interstitial connective tissue between bundles (stroma) (H & E stains x 100).
However, in fish fed diet (D7) containing 10% water hyacinth from polluted source the dorsal muscle had normal arrangement of muscle bundles with medium diameter, density and interstitial connective tissue between fiber bundles. Increasing water hyacinth from polluted source to 20% showed abnormal arrangement of muscle bundles, with large diameter and low density. While large area of the interstitial connective tissue was found between fiber bundles (Plate 33). Similar finding was observed in the dorsal muscle of fish fed diet (D9) containing 30% water hyacinth from polluted source showing abnormal arrangement of muscle bundles, Muscle bundles with small diameter and high density in some areas. While small or large areas of the interstitial connective tissue were found between fiber bundles (Plate 34). Finally, the dorsal muscle of fish fed diet (D10) containing 40% water hyacinth from polluted source showing muscle bundles with small diameter and high density. Small area of the interstitial connective tissue was found between fiber bundles (Plate 35). Based on the observed findings the histogenesis of the dorsal muscle was not affected by feeding fish on different level of water hyacinth from clean or polluted source, but some histometric changes occurred in diameter and density of fiber bundles and size of stroma (interconective tissue) between fiber bundles.
In conclusion, the histological examination cleared no pathological lesions in liver and kidney or pathological effects on gills and the dorsal muscles when fish were fed diets in which protein of soybean meal was replaced by up to 20% water hyacinth from clean source or 10% water hyacinth from polluted source.
In conclusion, the histological examination cleared no pathological lesions in liver and kidney or pathological effects on gills and the dorsal muscles when fish were fed diets in which protein of soybean meal was replaced by up to 20% water hyacinth from clean source or 10% water hyacinth from polluted source.
Plate (33): Section in dorsal muscle of fish fed diet (D8) containing 20% water hyacinth from polluted source showing abnormal arrangement of muscle bundles, Muscle bundles with large diameter and low density. While large area of the interstitial connective tissue was found between fiber bundles (H & E stains x 100).
Plate (34): Section in dorsal muscle of fish fed diet (D9) containing 30% water hyacinth from polluted source showing abnormal arrangement of muscle bundles, Muscle bundles with small diameter and high density in some areas. While small or large areas of the interstitial connective tissue were found between fiber bundles (H & E stains x 100).
Plate (35): Section in dorsal muscle of fish fed diet (D10) containing 40% water hyacinth from polluted source showing muscle bundles with small diameter and high density. Small area of the interstitial connective tissue was found between fiber bundles (H & E stains x 100).
REFERENCES
Abdelhamid, A.M.; Ahmed, A.M. and El-Melegy, Kh.M. (2002-a). Detoxification of aflatoxin contaminated diet by some physical and chemical means. J. Agric. Sci. Mansoura Univ., 27: 8213 - 8224.
Abdelhamid, A.M., Khalil F.F.; El-Barbary M.I., Zaki, V.H. and Husien, H.S. (2002-b). Feeding Nile tilapia on Biogen® to detoxify aflatoxic diets. Proc. 1st Ann. Sc. Conf. Anim. & Fish Prod. Mansoura, 24 & 25 Sep., pp. 207 - 230.
Abdelhamid, A.M.; Magouz, F.I., El-Mezaien, M. I. B., El-S. Khlafallah, M.M. and Ahmed, E. M. O. (2010). Effect of source and level of dietary water hyacinth on Nile tilapia, Oreochromis niloticus, performance. Engormix.com, Aquaculture Technical Article, 13 p. (J. of Animal and Poultry Production, Mansoura University, 1 (4): 133 - 150).
Abdelhamid, A.M., Magouz, F.I.; Salem, M.F.E., Mohamed, A.A. and Mohsen, M.K. (2002-c). Effect of graded levels of aflatoxin B1 on growth performance and biochemical, chromosomal and histological behavior of Nile tilapia Oreochromis niloticus, Proc. 1st Conf. Animal & Fish Prod., Mansoura, 24 & 25, Sept., pp. 231 - 250.
Bakeer, M.N. (2009). Trade and marketing of tilapia fish in Egypt. ASMAK, Fish World Magazine (Egyptian Fish Council), Oct., No. 10, pp: 22 - 24.
Boonyaratpalin, M., Supamattaya, K., Verakunpiriya, V. and Suprasert, D. (2001). Effects of aflotoxin B1 on growth performance, blood components, immune function and histopatological changes in black tiger shrimp (Paneus monodon Fabricius). Aquac. Res., 32 (suppl. 1): 388-398.
El-Sayed, A.F.M. (2006). Tilapia Culture. CABI Publishing, UK.
Kandil, W. M., S. M. Sirag, A. M. Abdelhamid, and T. M. Dorra (1991). Histopathological studies on mycotoxicoses in broiler chicks. Mansoura Medical Journal, 21: 193-204.
Pearse, G.W. (1968). Histological effects and diagnostic problems of mycotoxins in poultry. Proc. 25th West States Poult. Dis. Conf., pp.76-79.
Roberts, R. J. (2004). Fish Pathology, 3rd edition, W.B. Saunders
Sivakami, S. and Ayyappan, S. (1991). Influence of different feeds on the body composition of silver carp Hypophthalmichthys molitrix Cultured in cages. National Symposium on New Hortzons in Freshwater Aquaculture, 22 - 25 January, 1991. Proceeoings, pp. 92 - 94.
Soliman, M.K.; Khalil, R.H.; Youssef, S.A. and Mahfouz, N.M. (2000). Aflatoxicosis among cultured freshwater fish. Abstracts AQUA-2000, Nice-France, May 2 - 6, p: 801.
Abdelhamid, A.M.; Ahmed, A.M. and El-Melegy, Kh.M. (2002-a). Detoxification of aflatoxin contaminated diet by some physical and chemical means. J. Agric. Sci. Mansoura Univ., 27: 8213 - 8224.
Abdelhamid, A.M., Khalil F.F.; El-Barbary M.I., Zaki, V.H. and Husien, H.S. (2002-b). Feeding Nile tilapia on Biogen® to detoxify aflatoxic diets. Proc. 1st Ann. Sc. Conf. Anim. & Fish Prod. Mansoura, 24 & 25 Sep., pp. 207 - 230.
Abdelhamid, A.M.; Magouz, F.I., El-Mezaien, M. I. B., El-S. Khlafallah, M.M. and Ahmed, E. M. O. (2010). Effect of source and level of dietary water hyacinth on Nile tilapia, Oreochromis niloticus, performance. Engormix.com, Aquaculture Technical Article, 13 p. (J. of Animal and Poultry Production, Mansoura University, 1 (4): 133 - 150).
Abdelhamid, A.M., Magouz, F.I.; Salem, M.F.E., Mohamed, A.A. and Mohsen, M.K. (2002-c). Effect of graded levels of aflatoxin B1 on growth performance and biochemical, chromosomal and histological behavior of Nile tilapia Oreochromis niloticus, Proc. 1st Conf. Animal & Fish Prod., Mansoura, 24 & 25, Sept., pp. 231 - 250.
Bakeer, M.N. (2009). Trade and marketing of tilapia fish in Egypt. ASMAK, Fish World Magazine (Egyptian Fish Council), Oct., No. 10, pp: 22 - 24.
Boonyaratpalin, M., Supamattaya, K., Verakunpiriya, V. and Suprasert, D. (2001). Effects of aflotoxin B1 on growth performance, blood components, immune function and histopatological changes in black tiger shrimp (Paneus monodon Fabricius). Aquac. Res., 32 (suppl. 1): 388-398.
El-Sayed, A.F.M. (2006). Tilapia Culture. CABI Publishing, UK.
Kandil, W. M., S. M. Sirag, A. M. Abdelhamid, and T. M. Dorra (1991). Histopathological studies on mycotoxicoses in broiler chicks. Mansoura Medical Journal, 21: 193-204.
Pearse, G.W. (1968). Histological effects and diagnostic problems of mycotoxins in poultry. Proc. 25th West States Poult. Dis. Conf., pp.76-79.
Roberts, R. J. (2004). Fish Pathology, 3rd edition, W.B. Saunders
Sivakami, S. and Ayyappan, S. (1991). Influence of different feeds on the body composition of silver carp Hypophthalmichthys molitrix Cultured in cages. National Symposium on New Hortzons in Freshwater Aquaculture, 22 - 25 January, 1991. Proceeoings, pp. 92 - 94.
Soliman, M.K.; Khalil, R.H.; Youssef, S.A. and Mahfouz, N.M. (2000). Aflatoxicosis among cultured freshwater fish. Abstracts AQUA-2000, Nice-France, May 2 - 6, p: 801.
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23 de junio de 2011
yes it a good job about Water Hyacinth on Nile Tilapia. but it should have the study on the effect on the proximate composition of the muscle. is their any residue remain in the flesh due to fed on water hyacinth from polluted sources.
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19 de marzo de 2011
Interesting article about Water Hyacinth on Nile Tilapia. The histology is very good but it lacks labeling of important cell organelles affected by the diet interventions/manipulations so that beginners can follow the discussion in the text.
GJ Lumasag, Ph. D.
Professor of Aquaculture
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Taylor Made Fish Farms
9 de septiembre de 2010
Thank you for an article well done about Water Hyacinth on Nile Tilapia. I found it very interesting. The internet format lends itself to the publication of the photomicrographs, which helps, because dragging through dry histology reports comparing the effects of the different diets, is a form of torture which I would not have been willing to participate in. Seeing is believing. The investigation of alternative feed stocks for aquaculture is an important part of this industries future, and good on you for doing the hard grind to progress it.
Question. - Does this mean that Aspergillus / aflatoxin is an inevitable contaminant of a water grown feedstock? - Or is the aflatoxin a consequence of post harvest storage? - or does the plant contain a toxin which mimics the effect of the aflatoxin?
Jeff Titmarsh
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