بررسی اثرات استفاده از افزودنی پروبیوتیک و پری بیوتیک در شیر بر شاخص های عملکردی و قابلیت هضم مواد مغذی در گوساله های هلشتاین

The purpose of this study was to evaluate the effects of feeding probiotic and peribiotic supplements on milk yield, feed intake, fecal consistency and digestibility of Holstein calves. Treatments included: 1- control group (no additive milk) 2- probiotic group (milk + 2 gr probiotic) 3- prebiotic group (milk + 4 gr peribiotic) 4- synbiotic group (milk + 2 gr probiotic and 4gr perbiotic). Calves were weighed at the age of 3, 30 and 63 days after milking and feed intake weight was measured and recorded for every calves from the age of 10 days to the end of the period. For diarrhea, feces were observed weekly and feces score and fluidity were examined. At the end of the experiment (7 final days), the total stools of livestock were separately collected and weighed 20% sample was taken to investigate digestibility of nutrients. The chemical composition of fecal specimens and experimental diets including dry matter, fat, organic matter and protein were determined according to the AOAC method. The results of the experiment showed that the highest mean weight in the age of 30 and 63 days was related to the calves that used probiotics and had a significant difference with other groups. The lowest mean weight at the age of 63 was related to the synbiotic diet. The worst conversion ratio was in the control group and had a significant difference with the group that consumed probiotics. The best feed conversion ratio was probiotic diet and had a significant difference with other groups (P <0.05). The highest digestibility of dry matter and organic matter belonged to the group that consumed probiotics and had a significant difference with other groups. The lowest fecal consistency was in the group that consumed probiotics and had a significant difference with other groups (P <0.05). The lowest stool consistency was related to the group that used probiotics and had a significant difference with other groups (P <0.05). In general, the results showed that the use of probiotic had a significant effect on the performance, health and digestibility of Holstein calves.