Effects Of Chromium Nicotinate And Cysteamine On Production Performance And Antioxidant Performance Of Buffalo In Summer

The purpose of this experiment was to study the effects of different levels of chromium nicotinate on the lactation performance,antioxidant performance,and rumen microbial diversity of buffalo under heat stress,and to determine the appropriate amount of chromium nicotinate added to the buffalo diet;in-depth study of the diet The effects of adding cysteamine hydrochloride,chromium nicotinate and the combination of cysteamine and chromium niacin on the lactation performance,antioxidant performance and rumen microbial flora of buffalo are the combination of cysteamine and chromium nicotinate Use to provide a theoretical basis.Experiment 1:The effect of different levels of chromium nicotinate on the lactation performance,antioxidant performance and rumen microbial composition of buffalo under heat stress.Based on the similar weight（615±21 Kg）,parity（4±1）and milk production（6±1 kg）,20 healthy Nili-Ravi buffaloes in the middle lactation period were selected.A single factor random block design was used,divided into 4treatments,each of which treated 5 buffaloes.GroupⅠwas the control group,fed the basic diet;GroupⅡadded 1.5 mg/（d·head）chromium nicotinate;GroupⅢadded 3 mg/（d·head）chromium nicotinate;GroupⅣadded 4.5 mg/（d·head）Chromium nicotinate.The trial feeding period is 1 week and the trial period is 4weeks.The results showed that:（1）Compared with the control group,the difference in body surface temperature and rectal temperature in the test group is not significant（P>0.05）.The respiratory frequency of the group with 3mg/（d·head）chromium nicotinate was significantly lower than that of the control group（P<0.05）.（2）Adding chromium nicotinate to the diet have no significant effect with the apparent digestibility of buffalo DMI,CP,NDF and ADF（P>0.05）.（3）The diet supplemented with 3 mg/（d·head）chromium nicotinate increased the milk production of buffalo by 7.7%（P<0.05）;the difference of milk protein rate,milk fat rate,total milk solids and non-fat solids among the groups Not significant（P>0.05）.（4）The rumen pH,acetic acid,propionic acid and butyric acid and other VFA of the test group were not significantly different from those of the control group（P>0.05）;NH₃-N and NH₃-N in the diet supplemented with 3 and 4.5 mg/（d·head）chromium nicotinate The MCP was improved,but the difference was not significant（P>0.05）;the dietary supplementation of 3 and 4.5 mg/（d·head）chromic nicotinate group had a significant increase in isobutyric acid compared with the control group（P<0.05）.（5）The content of C14:1n5 and C16:1n7 in the diet supplemented with 3mg/（d·head）chromium nicotinate group was significantly higher than that in the control group（P<0.05）;C18:2（cis-9,trans-11）.The contents of C20:2n6,C20:5n3（EPA）,C22:6n3（DHA）and C24:0 were increased to varying degrees compared with the control group,but the differences were not significant（P>0.05）;Saturated fatty acids decreased to varying degrees compared to the control group,unsaturated fatty acids increased to varying degrees,but the differences were not significant（P>0.05）.（6）Compared with the control group,the CAT and INS of the buffalo serum in the test group were not significantly different from the control group（P>0.05）;the T-SOD in the diet supplemented with 1.5 and 3 mg/（d·head）chromium nicotinate was significantly higher than that in the control group Increased（P<0.05）;MDA in the 3mg/（d·head）chromium nicotinate group was significantly lower than that in the control group（P<0.05）;T3（triiodothyronine in the 3mg/（d·head）chromium nicotinate group Acid）and T4（thyroxine）were significantly increased compared with the control group（P<0.05）;Cortisol in the experimental group was significantly decreased compared with the control group（P<0.05）.（7）Compared with the control group,the total protein,albumin,globulin,alanine aminotransferase,urea nitrogen and total cholesterol in the experimental group were not significantly different（P>0.05）.The aspartate aminotransferases in the 1.5 and 3 mg/（d·head）chromium nicotinate group were significantly higher than those in the control group（P<0.05）.（8）The number of protozoa in the diet supplemented with 1.5 and 3 mg/（d·head）chromium nicotinate was significantly lower than that in the control group（P<0.05）;compared with the control group,the number of bacteria in each test group was significantly increased（P<0.05）;The number of methanogens in the 3 and 4.5 mg/（d·head）chromium nicotinate group was significantly higher than that in the control group（P<0.05）.（9）At the phylum level,the predominant flora of each group of buffaloes is Bacteroidetes,Firmicutes,and Proteobacteria;the dominant flora at the genus level is Prevotella 1,Christensenellaceae R-7 group.Experiment 2:The purpose of this experiment is to study the effect of adding cysteamine and chromium nicotinate to the buffalo diet on the lactation performance,rumen fermentation parameters,antioxidant performance and rumen microbial diversity of buffalo.Select 20 healthy Nile-Rafi milk buffaloes with similar body weight（615±21 Kg）,parity（4±1 births）and milk production（6±1 Kg）.A single-factor randomized block design was used,divided into 4 groups（groups I,II,III and IV）,with 5buffaloes in each group.GroupⅠis the control group,fed the basic diet.GroupⅡadded 22.5 g/day/head cysteamine;GroupⅢadded 3 mg/day/head chromium nicotinate;GroupⅣadded（22.5 g cysteamine+3 mg chromium nicotinate）/day/head.The pre-feeding period is 1 week and the test period is 4 weeks.The results showed that:1)The addition of chromium nicotinate and cysteamine had no significant effect on the surface temperature and respiratory rate of buffalo（P>0.05）.Compared with groupⅠ,the rectal temperature in groupⅣdecreased significantly（P<0.05）.2)The dry matter intake of groupⅠwas significantly lower than that of groupsⅡandⅣ（P<0.05）.The apparent digestibility of crude protein and neutral detergent fiber in groupⅣwas significantly higher than that of groupⅠ（P<0.05）.3)The milk production of groupⅣis significantly higher than that of groupsⅠ,ⅡandⅢ（P<0.05）.The milk yield of 4%milk fat correction in groupsⅢandⅣis significantly higher than that of groupsⅠandⅡ（P<0.05）.The milk protein rate of groupⅢwas significantly higher than that of groupⅠand groupⅣ（P<0.05）.The total solids of milk in groupⅢwas significantly higher than other groups and the lowest in groupⅠ（P<0.05）.4)The content of acetic acid in groupⅡand groupⅢwas significantly higher than that in groupⅠ（P<0.05）.The content of propionic acid in groupⅠwas significantly lower than that in groupsⅡ,ⅢandⅣ（P<0.05）.The total VFA yield and microbial protein content in groupⅠwere significant Lower than GroupⅡ,GroupⅢand GroupⅣ（P<0.05）.The differences of butyric acid,acetic acid/propionic acid,ammonia nitrogen,pH,and isovaleric acid content in each group were not significant（P>0.05）.5)C12:0,C14:0,C18:2（cis-9,trans-11）,C20:3n3 in milk of groupⅠwere significantly higher than that of groupⅣ（P<0.05）.C16:0 in milk of groupⅠwas significantly higher thanⅢGroupⅣand GroupⅣ（P<0.05）.The milk C20:0 content in GroupⅠwas significantly higher than that in GroupⅢ（P<0.05）.6)There was no significant difference in serum catalase,total superoxide dismutase and glutathione peroxidase levels among the groups（P>0.05）;the serum malondialdehyde content in groupⅠwas significantly higher than that in groupsⅡandⅣ（P<0.05）;The total antioxidant capacity of groupⅠwas significantly lower than that of groupⅣ（P<0.05）.The levels of serum insulin adrenocorticotropic hormone HSP 70 were not significantly different among the groups（P>0.05）;the serum growth hormone content in groupⅠwas significantly lower than that in groupsⅡandⅣ（P<0.05）.The serum estradiol content in groupⅢwas significantly higher In groupⅠand groupⅡ（P<0.05）.7)Serum T3 content in groupⅣwas significantly higher than that in groupⅠ（P<0.05）.Aspartate aminotransferase in groupⅢwas significantly higher than that in groupⅠ（P<0.05）.8)Dietary supplementation of chromium nicotinate and cysteamine can significantly increase the number of bacteria in buffalo rumen fluid（P<0.05）.GroupⅡsignificantly increased the number of methanogens in buffalo rumen fluid（P<0.05）.9)Compared with groupⅠ,the number of OTUs in groupsⅡ,ⅢandⅣdecreased.The abundance of Bacteroides phylum in groupsⅡandⅢincreased compared with groupⅠ,while the abundance of chlamydomonas decreased in groupⅠ.It can be seen that the addition of cysteamine and chromium nicotinate to the buffalo diet significantly affects the buffalo DMI,apparent digestibility,lactation performance,rumen fermentation parameters and rumen microbial composition,which in turn affects the buffalo performance.Conclusions:The diet supplemented with 3 mg/（d·head）chromium nicotinate can improve the lactation performance and antioxidant performance of buffalo,and the effect is better than other groups.The addition of cysteamine and chromium nicotinate in the diet can increase the milk production of buffaloes and improve the ability to resist heat stress,which is conducive to the growth of intestinal flora.