The Use of Bovine Colostrum as a Source of Immunoglobulin (Ig) for Lambs

Abstract

A study on the use of bovine colostrum as an alternative source of immunoglobulin for lambs was carried out at the University of Ghana’s Agricultural Research Centre — Legon. The study involved a total of fifty-six lambs. Thirty-three of them were bottle-fed with frozen bovine colostrum that was thawed whilst the remaining (twenty-three) were allowed to suckle their dams and served as the control. The mean serum immunoglobulin concentrations for the two groups of lambs were measured before the first feeding and thereafter at 6 hrs intervals till 48 hrs postpartum. The growth rates and mortalities for the two groups were also recorded over a period of 42 days. The mean serum immunoglobulin (Ig) concentrations of the normally suckled and the bovine colostrum-fed lambs were 21.01 and 18.26 zst units, respectively. There was no significant (P>0.05) difference in Ig levels of the two groups of animals. The peak serum Ig level for the bovine colostrum-fed lambs, however, on the average occurred at 12 hrs postpartum whilst that for the normally suckled lambs occurred at 24 hrs postpartum. The time of peak serum of bovine colostrum-fed lambs occurred earlier in Nungua Blackhead (6 hrs). Sex of lamb had relatively very little effect on immunoglobulin concentration and time of peak Ig in both the normally suckled and bovine colostrum-fed group. The growth pattern of the bovine colostrum-fed lambs at 42 days compared favourably with that of the normally suckled ones. Lambs that died in both groups before the end of the first week did so due to starvation caused by mis-mothering (rejection) by their dams rather than infection. It was therefore concluded that in a developing country like Ghana where knowledge and availability of artificial colostral substitutes/supplements are very limited, bovine colostrum could be an effective alternative to ovine colostrum in situations where an ewe dies postpartum or cannot lactate normally. This study also examined the nutritional composition of bovine and ovine colostrum. Pooled colostrum samples were collected from two cattle breeds (Sanga and Friesian- Sanga Crosses) and two breeds of sheep (Nungua Blackhead and Djallonke) in the dry and wet seasons. The samples were analyzed for total solids, protein and minerals to compare the nutritional parameters among the different breeds. The mean value for the protein and total solids content of the bovine colostrum, 12.36 and 16.21%, respectively, were significantly (P<0. and 05) lower than those for the ovine colostrum (14.56 and 22.16% respectively. With respect to bovine colostrum, total solids and protein were higher in the Crosses (19.15 and 13.93% respectively) than in the Sanga breed (16.11 and 12.89%, respectively). With the exception of phosphorus and potassium, the Sanga colostrum was higher in all the major and minor minerals. Similarly colostrum from the Djallonke breed had higher total solids (24.71%) and protein (17.38%) than those from the Nungua Blackhead sheep (21.45 and 13.97 % respectively). Phosphorus and Mg were higher in the Nungua Blackhead, while the Djallonke colostrum was higher in the rest of the minerals. No significant (P>0.05) seasonal variations were observed for the nutrients in bovine colostrum, though the nutrient concentrations were elevated in the dry season compared to those in the wet season. In contrast, ovine colostrum had significantly (P<0.05) higher concentrations of nutrients in the dry season. In addition, storage of bovine colostrum for 6 months at a temperature of -4°C had no significant effect on the nutritional quality of the colostrum. The results of the study showed ,that even though bovine colostrum could be used to feed lambs, there was early cessation of absorption of bovine immunoglobulins by the gut of lambs. Lambs should therefore be fed as much of the bovine colostrum within the first 12 hrs of life. Ideally, bovine colostrum should be collected in the dry season since colostrum collected in the dry season had higher total solids and proteins than in the rainy season. Bovine colostrum intended to be used for feeding lambs could be stored for as long as 6 months without any deterioration in nutritional quality.