Economical organic material like rice husk, sawdust, pine shaving, wood shavings, pea nuts hulls, straw, coconut husks & other dry-absorbent are used as bedding material / litter in poultry operation.
Though materials are selected keeping in mind the economics & easy availability which are regional based, the cost of above mentioned materials for broiler chicken bedding has risen considerably over the last few years.
Availability of new litter materials on time is also becoming a measure concern now days and even new litter materials are not hygienic. The new litter material which is used for bedding is procured from various sources. It is not healthy and may have high to very high contamination levels of bacterial groups and fungi.
Despite an increasing problem of procuring litter bedding due to scarcity of suitable litter materials in many broiler growing regions, one of the most common questions commonly asked by poultry farmer in our region thinking about reuse of old poultry litter is regarding the safety of reuse of buildup litter.
Farmers are not conversant to reutilize old buildup litter due to lack of awareness to handle following:
- Build up of microbial load in the old litter
- Emission of ammonia from old litter
- Darkling Beetles etc.
With little advance planning and a minimal investment, these problems can be reduced or eliminated.
Litter can be reused successfully if above problem can be managed properly. Poultry raisers in developed country are strong advocators of reusing the litter and as often as for 15 - 30 times, while Brazil producers replace the litter every 6 - 10 lots as they score high for treated old litter due to following benefits:
- Saves on labour cost involved in for clean out
- No difficulties in obtaining sufficient bedding material at no extra cost
- Treated old litter naturally exposes to young birds to low level & attenuated types of micro-organism for better immunity.
- Reduced environment pollutions
- Treated old litter is more hygienic than new litter materials
- With BMPs (Best Management Procedures) saves cost & time.
BMPs and a good sanitation program must be in place in order to maintain a successful use of old litter.
Recycling of litter has become attractive for broiler growers for many reasons in developed countries. The cost of replacing litter in grow out house has become very expensive (Malone, 1983). Cost & scarcity of litter materials have resulted in routine reuse of broiler litter without rious effects on broilers grow outs (Kennard & Chamberland, 1951; Jones & Hagler, 1983). New litter has been reported to favour the survival of E.coli & Salmonella more than old litter in which organism tend to die out more rapidly because of competition from the bacteria present in built-up litter (Botts et.al., 1952; Snoeyenbos et al., 1967; Duff et al., 1973). Furthermore, previously used & built-up litter aids birds in developing competitive organism in the gut, thus inhibiting salmonella´s colonization (Fanelli et al., 1970). Bacon & Burdick (1977) and Jones & Hagler (1983) reported that fungal numbers were lower in old litter than in new litter.
Treated litter is commonly used in poultry houses in deep litter system for reducing harmful ammonia level & bacterial load by lowering pH of litter. The poultry litter has an average pH of 8.0 - 9.0; this is considered a high pH i.e. alkaline. The pH can influence the ammonia volatilization. Ammonia release from litter is reduced when litter pH is below 6; emission exceeds when pH is 7 and above. At litter pH lower than 4.6, the economically devastating bacteria like E.coli, Salmonella, Clostridium, and Campylobacter do not grow.
A study was conducted to determine the efficacy of Treated Litter to understand the bacterial load in litter.
One poultry house with litter of rice husk on which one flock of broiler had been raised was used in the study. Litter treatment process carried out on 10th day of brooding of chicks. The active ingredients activated immediately as and when they came in contact with excreta of birds / moisture of buildup litter, ammonia formation was reduced as treatment reduced litter pH up to 4.
To evaluate the efficacy for reducing microbial load in litter, litter samples were collected for pathological test before start of litter treatment and on 21st day after litter treatment.
Litter sample collection method
Collected 100 gm of litter sub-sample each from 11 location of poultry house i.e. one from center of poultry house and other 10 from the middle between centre & each corner of poultry house (See Sampling Site Diagram) before treatment of litter & after treatment of litter.
Litter Sampling Site Location in a Poultry House
Each sub-sample were placed in clean & sanitized plastic bucket & mixed thoroughly. Then at least 100 gm mixtures were filled into a Zip-lock plastic bag and sealed tightly. Zip-lock plastic bag capacity of 250 gm was used for sample collection to make room in the bag in case gas is produced to expand plastic bag.
Sample of litter collected on time before treatment of litter & after treatment of litter were sent to Pathology Laboratory on the same day it is prepared.
Trials conducted confirmed:
- Acidification Stopped NH3 production
- Reduced TVC (CFU/g) up to 97.12%
- Eliminated E.Coli / Salmonella.
Repeat Use of Litter
When possible, remove all crusted & wet litter and disinfect (With highly effective disinfectant) the shed. Remove all cake formation from litter & maintain humidity of house in between 50% to 75%. Treat litter with appropriate litter conditioner. After similar action the old litter can be used again & again minimum up to 10 times.
Prevention of Darkling beetle
The Lesser mealworm or Darkling beetle (Alphitobius diaperinus) and the Hide Beetle (Dermestes maculates), adults and larvae of both species can become extremely abundant in poultry manure and litter. The large beetle populations may become a public nuisance at cleanout time because of adult migration from the fields where the manure is spread into nearby residential areas.
Both beetles can cause extensive damages:
· They feed on poultry feed stocks.
· They bore into structural materials.
· They are vector (transmitter) & serve as reservoir for several poultry disease pathogens.
· They may bite birds & damage skin of birds reducing carcass quality.
Most insecticide loses their effectiveness against beetles within days or few weeks after application and is also hazardous to poultry & care takers. The lifecycle of beetle could be disrupting on poultry litter floor by using safe litter conditioner which bring down litter pH <5.
Note: Use nonhazardous & nontoxic substances classified as GRAS (Generally Regarded as safe) and may be mixed with approved insecticide for better result if required for extended period of time. However, avoid using materials such as agricultural lime (CaCO3), hydrated or slaked lime (Ca(OH)2), or burnt lime (CaO) since they increase litter alkalinity (to a pH greater than 7) and alkalinity makes favorable condition for pathogenic bacteria to grow and also converts more of the ammonium into ammonia gas. This can become an environmental problem.