In poultry nutrition, most attention is given to protein products, due to the importance of protein as a major constituent of the biologically active compounds in the body. It also assists in the synthesis of body tis...In poultry nutrition, most attention is given to protein products, due to the importance of protein as a major constituent of the biologically active compounds in the body. It also assists in the synthesis of body tissue, for that renovation and growth of the body. Furthermore, protein exists in form of enzymes and hormones which play important roles in the physiology of any living organism. Broilers have high dietary protein requirements, so identification of the optimum protein concentration in broiler diets, for either maximizing broiler performance or profit, requires more knowledge about birds' requirements for protein and amino acids and their effects on the birds' growth performance and development. It also requires knowledge about the protein sources available that can be used in poultry diets. The broad aim of this review is to highlight the importance of some of the available high-quality specialized protein products of both animal and plant origins which can be explored for feeding broiler chickens. Minimization of the concentration of anti-nutritional factors(ANFs) and supplementation with immunologically active compounds are the main focus of gut health-promoting broiler diets. These diet characteristics are influenced by feed ingredient composition and feed processing. The general hypothesis is that these protein products are highly digestible and devoid of or contain less ANFs. Feeding these products to broiler chicks, especially at an earlier age, can assist early gut development and digestive physiology, and improve broiler growth performance and immunity.展开更多
A total of 294 one-day-old Cobb broiler chickens were used to investigate the effects of four Lactobacillus strains on gut microbial profile and production performance. The six dietary treatments, each with 7 replicat...A total of 294 one-day-old Cobb broiler chickens were used to investigate the effects of four Lactobacillus strains on gut microbial profile and production performance. The six dietary treatments, each with 7 replicates were: 1) basal diet(negative control), 2) one of four strains of Lactobacillus(tentatively identified as Lactobacillus johnsonii, Lactobacillus crispatus, Lactobacillus salivarius and an unidentified Lactobacillus sp.) and 3) basal diet with added zinc-bacitracin(ZnB, 50 mg/kg). Results showed that the addition of probiotic Lactobacillus spp. to the feed did not significantly improve weight gain, feed intake and feed conversion rate(FCR) of broiler chickens raised in cages during the 6-week experimental period,but tended to increase the number of total anaerobic bacteria in the ileum and caeca, and the number of lactic acid bacteria and lactobacilli in the caeca; and to significantly increase the small intestinal weight(jejunum and ileum). Furthermore, all 4 probiotics tended to reduce the number of Enterobacteria in the ileum, compared with the control treatments. The probiotics did not affect the p H and the concentrations of short chain fatty acids(SCFA) and lactic acid in both the ileum and caeca.展开更多
The effects of Lactobacillus johnsonii(L. johnsonii) on gut microflora, bird performance and intestinal development were assessed using 288 one-day-old Cobb broilers challenged with Salmonella sofia(S.sofia). The expe...The effects of Lactobacillus johnsonii(L. johnsonii) on gut microflora, bird performance and intestinal development were assessed using 288 one-day-old Cobb broilers challenged with Salmonella sofia(S.sofia). The experiment was a 3×2 factorial design which consisted of three treatments, a negative control(NC) with no additives, a positive control(PC) containing antimicrobials(zinc-bacitracin, 50 mg/kg) and a probiotic group(Pro), and with the two factors being unchallenged or challenged with S. sofia.A probiotic preparation of L. johnsonii(10~9 cfu/chick) was administered to chicks individually by oral gavage on days 1, 3, 7 and 12. Chicks were individually challenged with S. sofia(10~7 cfu/chick) by oral gavage on d 2, 8 and 13. Results showed that the challenge itself markedly reduced(P < 0.05) bird performance and feed intake. And, transient clinical symptoms of the infection with S. sofia were observed from the second time they were challenged with S. sofia in the negative challenge groups. The novel probiotic candidate L. johnsonii reduced the number of S. sofia and Clostridium perfringens in the gut environment, and improved the birds’ colonization resistance to S. sofia.展开更多
文摘In poultry nutrition, most attention is given to protein products, due to the importance of protein as a major constituent of the biologically active compounds in the body. It also assists in the synthesis of body tissue, for that renovation and growth of the body. Furthermore, protein exists in form of enzymes and hormones which play important roles in the physiology of any living organism. Broilers have high dietary protein requirements, so identification of the optimum protein concentration in broiler diets, for either maximizing broiler performance or profit, requires more knowledge about birds' requirements for protein and amino acids and their effects on the birds' growth performance and development. It also requires knowledge about the protein sources available that can be used in poultry diets. The broad aim of this review is to highlight the importance of some of the available high-quality specialized protein products of both animal and plant origins which can be explored for feeding broiler chickens. Minimization of the concentration of anti-nutritional factors(ANFs) and supplementation with immunologically active compounds are the main focus of gut health-promoting broiler diets. These diet characteristics are influenced by feed ingredient composition and feed processing. The general hypothesis is that these protein products are highly digestible and devoid of or contain less ANFs. Feeding these products to broiler chicks, especially at an earlier age, can assist early gut development and digestive physiology, and improve broiler growth performance and immunity.
文摘A total of 294 one-day-old Cobb broiler chickens were used to investigate the effects of four Lactobacillus strains on gut microbial profile and production performance. The six dietary treatments, each with 7 replicates were: 1) basal diet(negative control), 2) one of four strains of Lactobacillus(tentatively identified as Lactobacillus johnsonii, Lactobacillus crispatus, Lactobacillus salivarius and an unidentified Lactobacillus sp.) and 3) basal diet with added zinc-bacitracin(ZnB, 50 mg/kg). Results showed that the addition of probiotic Lactobacillus spp. to the feed did not significantly improve weight gain, feed intake and feed conversion rate(FCR) of broiler chickens raised in cages during the 6-week experimental period,but tended to increase the number of total anaerobic bacteria in the ileum and caeca, and the number of lactic acid bacteria and lactobacilli in the caeca; and to significantly increase the small intestinal weight(jejunum and ileum). Furthermore, all 4 probiotics tended to reduce the number of Enterobacteria in the ileum, compared with the control treatments. The probiotics did not affect the p H and the concentrations of short chain fatty acids(SCFA) and lactic acid in both the ileum and caeca.
文摘The effects of Lactobacillus johnsonii(L. johnsonii) on gut microflora, bird performance and intestinal development were assessed using 288 one-day-old Cobb broilers challenged with Salmonella sofia(S.sofia). The experiment was a 3×2 factorial design which consisted of three treatments, a negative control(NC) with no additives, a positive control(PC) containing antimicrobials(zinc-bacitracin, 50 mg/kg) and a probiotic group(Pro), and with the two factors being unchallenged or challenged with S. sofia.A probiotic preparation of L. johnsonii(10~9 cfu/chick) was administered to chicks individually by oral gavage on days 1, 3, 7 and 12. Chicks were individually challenged with S. sofia(10~7 cfu/chick) by oral gavage on d 2, 8 and 13. Results showed that the challenge itself markedly reduced(P < 0.05) bird performance and feed intake. And, transient clinical symptoms of the infection with S. sofia were observed from the second time they were challenged with S. sofia in the negative challenge groups. The novel probiotic candidate L. johnsonii reduced the number of S. sofia and Clostridium perfringens in the gut environment, and improved the birds’ colonization resistance to S. sofia.