Investigating Effects Of Bovine Colostrum On Performance And Its Mechanism In Segregated Early-Weaned Pigs

Four experiments were conducted to investigate the effect of bovine colostrum on performance, nutrient metabolism, development in segregated early-weaned pigs. In Experiment 1, 33 crossbred pigs weaned at 14±2 days of age, with an average weight of 3.29kg,were used to investigate the effect of feeding different diets ( bovine colostrum type:containing bovine colostrum 60%, 30%, 15%; milk type:containing whole milk powder60%, 30%, 10%; no milk type) during 14-28 days on performance of pigs from 14-60 days of age. The results showed: the type of diets influenced performance of SEW pigs significantly(P<0.05). Bovine colostrum type improved performance of pigs notably(P<0.05). Pigs fed diet containing high concentration of bovine colostrum wasn't depressed after weaning. Milk type diets had no advantage of improving performance of pigs. Performance of pigs was decreased seriously.by feeding no milk diet. In Experiment 2, 16 crossbred pigs weaned at 14±2 days of age,with an average weight of 3.64kg ,were used to study the effect of the first phase(14-28days)diets containing DE, bovine colostrum whey(milkborne factors), protein sources equal to those in 1.1group in experiment 1 , but different protein level(34%, 26%, 20%) on performance of pigs. The results showed, , the first phase diets with equal DE,but different protein level influenced performance of pigs from 14-60 days of age. Performance of pigs fed diet with energy:protein ratio of 12.95(DE4.4Mcal/kg, CP26%) was best,but was decreased by diets with high or low energy:protein ratio. ADFI wasn't influenced by feeding diets with equal bovine colostrum whey ,different protein level. (P>0.05). In Experiment 3, 24 crossbred pigs weaned at 14±2 days of age, with an average weight of 2.87kg ,were used to investigate the effect of feeding different diets ( 100%bovine colostrum , 60% bovine colostrum ,60% whole milk powder, no milk diet).in first phase on utilization of nutrient for pigs and the effect of diet composition on morphology of pigs'intestines. The results showed, during 14-28 days , pigs digested protein and fat originating from milk more easily than those from no milk diet. No milk ingredient in diet decreased fat digestibity. Serum urea nitrogen was increased and BV of protein was reduced.by feeding no milk diets, high protein diet. Villi of SEW pigs got longer than that of nursing pigs at age of 28days (P<0.05). Composition of diets influenced intestinal morphology. In pigs fed diet containing high concentration of bovine colostrum, the length of villi and villi:vrypt ratio were higher than that of other groups(P<0.05). In Experiment 4, according to the design and treatment in experiment 3, the effects of bovine colostrum on passive immunity, production of antibodies , composition of microorganism in intestines of pigs were investigated. The results showed , pigs fed 100% bovine colostrum diet during 14-28 days, absorbed a few bovine IgG at 28 days of age. Bovine colostrum depressed E.coli in large intestines , and improved production of antibodies of pigs. Based on this study, it was concluded that bovine colostrum and SEW accelerated development of intestines in pigs. Bovine colostrum whey(milkborne factors) was a protecting-health factor which provided effective immune protection and improved performance of pigs at age of 14-28 days. The earlier pigs weaned (the lighter weight), the more pigs depended on protecting-health factor. It was advantageous of improving performance of pigs fed diets formulated according to energy:protein ratio of NRC(1998) for pigs at age of 14-28 days, provided with enough milkborne factors, increased nutrient concentration. The common function of protecting-health factor and nutrient in diets were the key for SEW pigs attaining perfect performance.