category: feed additives
authors: m. terré , m. verdú, a. frongia , r. cresci, and m. blanch
book/journal:2020 adsa annual meeting, poster m105
there are several feed additives used for dairy calves that cause palatability problems. a model to cause milk replacer (mr) aversion to dairy calves was developed. the model consisted on adding 30 g/kg of a mix of commercial products with bitter taste (bittermix) to the mr, and animals who received bittermix (bm) had more mr refusals, and a decrease in the mr intake rate. to evaluate the potential of 2 sensory additives differing in the sweet fraction to mask bm aversion in the mr, 37 holstein male calves (6.5 ± 0.93 d of age and 40.2 ± 1.40 kg of bw) were raised under the same conditions following a common mr (25.3% cp, 21.1% fat) feeding program. when calves (38.5 ± 1.12 d of age and 57.7 ± 1.70 kg of bw)were able to consume 8 l/d at 12.5% dm concentration in 2 feedings, the aversion test was performed adding one of the following products to the mr: no supplementation (ctrl; n = 9); bm at the dose of 30 g of bm/kg of mr; (bm; n = 9); bm plus sensory additive 1 at the dose of 2 g/kg of mr (sa1; n = 10); and bm plus sensory additive 2 at the dose of 2 g/kg of mr (sa2; n = 9). the aversion test lasted 7 d, and mr intake and time devoted to consume the mr were recorded at each feeding throughout the aversion week. data were analyzed with a mixed-effects model accounting the fixed effects of mr supplementation, feeding during the aversion week, and their interaction, and calf as random effect. the incidence of mr refusals was analyzed with a generalized mixed model considering treatment as fixed effect. the incidence of refusals and time devoted to consume the mr were similar in all 4 treatments. however, the eating rate of calves supplemented with sa2 was similar to ctrl calves, in contrast to calves supplemented with sa1 that had similar eating rate to bm calves. sensory additive 2 was able to revert the aversion effects of bm exhibiting a similar mr eating rate than ctrl calves.