Effects of Different Levels of Colostrum Intake on the Severity of Porcine Epidemic Diarrhea in Piglets

Porcine Epidemic Diarrhea (PED) is a severe enteric disease that causes economic losses worldwide. Maternal passive immunity can prevent losses in suckling piglets during the period of immature immune system. Since sow colostrum is the most abundant and easily accessible resource of a farm. The aim of this study was to examine the effects of different levels of piglet colostrum intake on clinical illness and histopathological lesions from PED virus (PEDV) infection.

The experiment was conducted in a PEDV positive farm that practiced a feedback of PEDV infected material to sows during gestation. Twelve new born piglets from the same litter were divided into 4 groups of 3 piglets with the same weight distribution between groups. Colostrum were obtained from the sow of this litter and given to the piglets of each group with different proportions of colostrum to milk replacer. Group 1 received 100 ml of milk replacer. Group 2 received a mixture of 25 ml of colostrum/75 ml of milk replacer. Group 3 received a mixture of 50 ml of colostrum/50 ml of milk replacer. Group 4 received 100 ml of colostrum. After 5 h, all the piglets were orally inoculated with 5 ml of 1x10⁵ TCID₅₀/ml PEDV solution. The piglets were then fed with 200 ml of milk replacer. Fecal consistency was scored as follows: 0, solid; 1, pasty; 2, semi-liquid; 3, liquid, respectively. At 22 h postinoculation, all piglets were euthanized and jejunum samples were collected for histopathology staining. Immunohistochemistry (IHC) staining of jejunum against PEDV was also performed. Intestinal villus heights were measured and ANOVA was used to compare the villus heights between each group.

Groups 1 and 2 received an average fecal score of 3 whereas score 1 was given to groups 3 and 4. All groups developed blunt and fused villi but were most prominent and extensive in groups 1 and 2. The IHC staining revealed PEDV in jejunal villus cells of all groups. Average villus heights of groups 1, 2, 3, and 4 were 254.40±47.40^a, 353.80±55.10^b, 406.46±15.65^b, and 415.10±76.70^b um, respectively. Villus heights of group 1 were significantly the shortest. Piglets that received the highest amount of colostrum were least affected by PED, and vice versa.

The amount of colostrum consumed by the piglets showed a positive correlation with protection against PED losses as high colostrum intake reduced the severity of diarrhea and intestinal lesions. Thus, colostrum management to ensure the maximum intake of maternal passive immunity by piglets is crucial for PEDV infected farm. Factors that affects colostrum yield and immune components should be further studied.

Disclosure of Interest: None Declared.