| Growth performance and immune performance are two important aspects to measure the body condition of piglets,which reflect the healthy level of growth and development of piglets.The transition period after weaning is a critical stage in pig production management as piglets are susceptible to digestive and respiratory tract infections that reduce feed intake and growth rate and increase the risk of diarrhoea.The main components in fish oil are eicosapentaenoic acid and docosahexaenoic acid.Fish oil is widely reported to benefit well-being of mammals including improving resistance and antioxidant capacity,yet its protective effect during suckling-to-weaning transition in piglets remains undetermined.In order to investigate the effects of fish oil(EPA+DHA≥22%)supplementation in late gestation and lactation of sows on growth performance and immune performance of offspring piglets,45 healthy "approximately gram × landrace" one-litter sows were randomly divided into three groups(control group,low supplemental group and high supplemental group).The experiment lasted from day 90 of gestation to one week after weaning.During the experiment,the blood and feces of piglets were collected,and the effects of fish oil supplementation on growth performance and gut microbiota of piglets were evaluated by measuring body weights,serum indicators,immunoglobulin,stress hormones,gut microbiota and post-weaning diarrhea.The main results were as follows:(1)When fish oil was added to sows during late gestation and lactation,the litter weight of piglets in 60g/d treatment group was significantly higher than that in control group(P <0.05);The diarrhea rate at 1 week after weaning was significantly decreased in the two treatment groups(P < 0.05).Compared with the control group,the concentration of T3 in30g/d group before weaning was significantly increased(P < 0.05),and the concentration of IGF-1 in serum was increased in a dose-dependent manner,and the differences between the two treatment groups were significant(P < 0.05).After weaning,T3 concentration of piglets in the two treatment groups increased(P = 0.055),IGF-1 concentration showed a dose-dependent increase,but the 60g/d treatment group was significantly higher than the control group(P < 0.05),and the cortisol concentration in the weaning group was significantly lower than that in the control group(P < 0.05).(2)When fish oil was added to sows during late gestation and lactation,serum Ig M concentration of piglets before weaning was significantly higher than that of control group(P < 0.05),and serum Ig G concentration of piglets in 60g/d treatment group was significantly higher than that of control group(P < 0.05).Serum Ig M,Ig A and Ig G concentrations of weaned piglets in 60g/d treatment group were significantly higher than those in control group(P < 0.05).Serum malondialdehyde(MDA),catalase(CAT)activity and IL-6 concentrations of piglets in fish oil treatment group were significantly higher than those in control group(P < 0.05).Serum concentrations of interferon γ(IFN-γ)and IL-1β of piglets in 60g/d treatment group were significantly higher than those in control group and30g/d group(P < 0.05).The creatine kinase level in blood of piglets treated with 30g/d was significantly decreased(P < 0.05).(3)When fish oil was added to sows during late gestation and lactation,compared with the control group,the serum concentrations of diamine oxidase(DAO),D-lactic acid and Zonulin before and after weaning of piglets in the fish oil supplementation group were significantly decreased(P < 0.05).Compared with the control group,PD＿whole tree index of fecal bacteria in fish oil low treatment group was significantly increased(P < 0.05);Chloroflexi and Acidobacteria abundance in the 30g/d group were significantly higher than those in control group(P < 0.05),the abundance of Lactobacillaceae in 60g/d fish oil group was significantly higher than that in 30g/d fish oil group(P < 0.05);Lactobacillus and uncultured＿bacterium＿f＿Muribaculaceae in the 60g/d treatment group were higher than those in the control group and the 30g/d treatment group(P < 0.05).Correlation analysis showed that Lactobacillus was significantly positively correlated with Ig A concentration in serum of piglets(P < 0.05),Ruminococcaceae＿UCG-002 was positively correlated with serum Ig M and T4 concentrations(P < 0.01),Synergistaceae and IGF-1 were negatively correlated(P < 0.05).These results indicate that fish oil supplementation in late gestation and lactation diets of sows can improve growth performance and immune performance of offspring piglets,reduce stress hormone levels,improve intestinal barrier integrity and enrich microbial diversity.Comprehensive consideration of 60 g fish oil daily supplemental level is more advantageous to the growth and development of piglets.This study revealed the effects of different doses of fish oil added to sows’ diets on growth performance and fecal flora of piglets,providing a new nutritional strategy for improving the health status of weaned piglets. |
PDF Full Text Request