Dietary saccharin sodium supplementation improves the production performance of dairy goats without residue in milk in summer

The purpose of this study was to investigate the effects of dietary saccharin sodium supplementation on production performance,serum biochemical indicators,and rumen fermentation of dairy goats in summer.Twelve Guanzhong dairy goats with similar body weight,days in milk,and milk yield were randomly divided into two dietary treatments:(1)CON:basal diet;(2)SS:basal diet+150 mg/kg saccharin sodium on the basis of dry matter.The experiment lasted 35 d,including 7 d for adaptation and 28 d for dietary treatments,sampling and data collection.Each dairy goat was housed individually in a clean separate pen with ad libitum access to diet and water.The goats fed SS diet had increased dry matter intake(DMI;P=0.037),4%fat corrected milk yield(P=0.049),energy corrected milk yield(P=0.037),milk protein yield(P=0.031),and total solids yield(P=0.036).Serum activity of aspartate aminotransferase(P=0.047)and concentrations of 70-kDa heat shock protein(P=0.090),malondialdehyde(P=0.092),and total protein(P=0.057)were lower in goats fed SS diet than those fed CON diet.Supplementation of saccharin sodium tended to increase activity of glutathione peroxidase in serum(P=0.079).The concentrations of rumen total volatile fatty acid(P=0.042)and butyrate(P=0.038)were increased by saccharin sodium supplementation.Dietary supplementation of saccharin sodium increased the relative abundance of Lachnobacterium(P=0.022),Pseudoramibacter(P=0.022),Shuttleworthia(P=0.025),and Syntrophococcus(P=0.037),but reduced the relative abundance of Prevotella_1(P=0.037)and Lachnospiraceae_UCG_008(P=0.037)in rumen.Saccharin sodium was observed in feces and urine of goats fed diet supplemented with saccharin sodium,but saccharin sodium was undetectable in the milk of goats receiving SS diet.In conclusion,administration of saccharin sodium was effective in increasing fat and energy corrected milk yield by increasing DMI and improving rumen fermentation and antioxidant capacity of dairy goats in summer.In addition,saccharin sodium residue was undetectable in the milk.