Supplementation of suckling beef calves on a creep-feeding system and nutritional evaluation of lactating beef dams

Resumo

This study was conducted to evaluate the productive and nutritional performance of suckling calves fed only a mineral mix (MM) or different levels of multiple supplement and the milk yield and nutritional parameters of beef cows on Uruchloa decumbens pastures. Thirty-two suckling calves, with an average age of 3 months and average initial weight of 109.3 ± 0.84 kg, and their respective mothers, with an average initial weight of 447.2 ± 47.1 kg, were used. The experimental design was completely randomized. The supplement contained approximately 25% crude protein (CP), and treatments consisted of the supply of different of multiple supplement levels for the calves. The levels of supply of the supplements were 0.2, 0.4, and 0.6% of the body weight for treatments N0.2, N0.4, and N0.6, respectively. The animals from the control treatment (MM) received only an MM ad libitum. The average daily gain (ADG) of the calves was 731.2, 810.6, 822.7, and 895.2 grams for treatments MM, N0.2, N0.4, and N0.6, respectively. Supplemented calves showed greater weight gain. The multiple supplement levels offered to the calves had a positive linear effect (P<0.10) on their ADG. The intakes in kg/ day of dry matter (DM), organic matter (OM), CP, non-fibrous carbohydrates (NFC), digestible DM, digestible neutral detergent fiber (NDF), and total digestible nutrients (TDN) were higher (P<0.10) for animals that received multiple supplements compared with those fed only an MM. The levels of supply of multiple supplements had an increasing linear effect on ether extract (EE) intake, and a quadratic effect was found on DM intake, forage DM, OM, forage OM, CP, NFC, digestible DM, and TDN. The total apparent digestibility coefficients of DM, OM, NDF, NFC, and TDN were higher (P<0.10) for the animals that received multiple supplements. With the levels of supply of multiple supplements, an increasing linear effect was observed on EE digestibility. Calf supplementation did not affect the performance, milk yield, or nutritional parameters of the cows (P>0.10).