Optimizing amla (Phyllanthus emblica) fruit powder supplementation in liquid feed fed to Holstein dairy calves: Insights from growth performance and health events

Abstract

Despite efforts at improvement, calf diarrhea remains one of the main problems in calf rearing. Amla (Phyllanthus emblica) fruit could be a good candidate to improve gut health due to its antimicrobial, gastro-protective, and immunomodulatory effects. This study aimed to evaluate the effect of amla fruit powder supplementation on frequency of diarrhea and growth performance of dairy calves. One hundred male Holstein calves [2-days (d)-old; 42.6 ± 1.7 kg body weight (BW)] were randomly assigned into five treatments, CON, PEF5, PEF10, PEF20, and PEF40, with 0, 5, 10, 20, and 40 g/d amla fruit powder (PEF) supplementation, respectively, and housed in individual hutches (n = 20 calves per treatment). The experiment lasted from 2 to 75 d of age (weaning) and calves were fed milk (2–7 d), milk replacer (8–75 d), and calf starter (2–75 d). The PEF supplementations were fed in two meals a day, equal amount each time, by mixing into milk or milk replacer. Feed intake and fecal score data were collected daily; BW and body frame measurements at 2, 14, 28, 42, and 75 d; and rumen fluid samples at 14, 28, 42, and 75 d. Starter and total dry matter intakes (DMI) differed among treatments during 22–75 with the highest in CON and linearly decreased with increasing PEF doses. Liquid feed DMI tended to decrease with increasing PEF doses. PEF supplementation had quadratic effect on body weight (BW), average daily gain (ADG), feed efficiency, body length, heart girth, and withers height. The BW and ADG differed among treatments during 29–75 and 15–75 d, respectively, with the highest in PEF5 followed by CON and lowest in PEF40. However, PEF did not improve BW and ADG compared to the CON. The overall feed efficiency in PEF5 was higher than in PEF20 and PEF40. PEF5 decreased the frequency of fecal score “3” (P = 0.02) while PEF5 (P < 0.01) and PEF10 (P = 0.03) increased the frequency of fecal score “1”, compared to the CON. Frequency of diarrhea in the PEF5 group (7.9%) was lower (P < 0.05) than all groups (11.1%, 14.3%, 22.6%, and 24.2% for PEF10, PEF20, and PEF40, respectively). Rumen fermentation (pH, ammonia-N, and volatile fatty acids) was not affected by PEF supplementation. However, ammonia-N showed a decreasing trend with increasing PEF levels. The results suggested that PEF could be fed at 5 g/d to reduce diarrhea in preweaning dairy calves.