Effect of supplemental energy source and frequency on growing calf performance1

Abstract

Crossbred heifers (n = 120; 265 kg, SD = 37) were fed individually (84 d) to determine the effect of supplement type, concentration, and frequency on intake and performance and to estimate the energy value of dry distillers grains plus solubles (DDGS) in a high-forage diet. Treatments were arranged in a 3 × 2 × 2 factorial, with 3 supplements, 2 concentrations, and 2 frequencies of supplementation. Supplements including dry-rolled corn (DRC), DRC with corn gluten meal (DRC + CGM), and DDGS were fed at 0.21% (LOW) or 0.81% (HIGH) of BW daily and were provided daily (DAILY) or 3 times weekly (ALT). Heifers were fed to consume grass hay (8.7% CP) ad libitum. Individual DMI, diet composition, BW, and ADG were used to calculate energy values for DDGS and DRC. Supplement type, concentration, frequency, and interactions were tested using the MIXED procedure of SAS, with BW included as a covariate. Supplement × concentration interactions for gain (P = 0.01) and G:F (P < 0.01) were detected. At the LOW concentration, heifers supplemented with DDGS gained more and were more efficient (P ≤ 0.03) than those supplemented with DRC or DRC + CGM. No performance differences were observed (P ≥ 0.22) between DDGS and DRC + CGM in HIGH treatments, although both improved (P ≤ 0.01) gain and G:F relative to DRC. Calculated TDN content of DDGS was 18 to 30% greater than DRC. Gain and G:F were improved (P < 0.01) in heifers fed HIGH vs. LOW. Total intake was greater (P < 0.01) for HIGH than LOW, but LOW heifers consumed more hay (P < 0.01) than HIGH. The DAILY heifers consumed more (P < 0.01) hay and total DM than the ALT heifers. The DAILY heifers gained more (P < 0.01) than ALT, but G:F was not affected (P = 0.85) by supplementation frequency. In a high-forage diet, DDGS has greater energy value than corn.

Frequency of concentrate supplementation for grazing beef cattle

“…Changes in the grazing behavior of animals receiving supplements at a lower frequency were observed by Pulido et al (2009) and Loy et al (2008). Based on these studies, infrequent supplementation may alter the feeding behavior of animals, which may lead to a lower intake of pasture DM.…”

“…However, if the frequency of supply of concentrate supplements is reduced to three times weekly, animals may display lower weight gains (ARTIOLI et al, 2015;COOKE et al, 2008;LOY et al, 2008). According to Cooke et al (2008), decreasing the frequency of energy supplementation to three times per week reduced the performance of beef heifers reared on pasture during the rainy season by 18%.…”

Reduced supplementation frequency increased insulin-like growth factor 1 in beef steers fed medium quality hay and supplemented with a soybean hull and corn gluten feed blend

“…Success of less frequent supplementation of energy based supplements may at least partially depend on availability of ruminal N for efficient microbial growth and digestion. Loy et al (2008) showed that the effects of supplementation frequency on gains of heifers consuming medium quality hay tended to differ depending on the source of protein used in the energy supplement. Hay intake was decreased but gains were not negatively affected by reducing supplementation frequency to 3 times a week when a supplement high in ruminally degradable protein (dry rolled corn plus urea) was fed.…”

“…Thus, the heifers supplemented with dry rolled corn and urea 3X had a greater gain to feed ratio than those supplemented daily in their study. Additionally, the purine derivative to creatinine ratio in the urine was greater for heifers supplemented with dry rolled corn plus urea 3X than those supplemented daily suggesting that heifers supplemented 3X absorbed more microbial protein (Loy et al, 2008).…”

Recria de bezerras de corte em pastagem de azevém sob frequências de suplementação

“…A mudança na frequência de suplementação tem sido estudada internacionalmente (BOHNERT et al, 2002;LOY et. al., 2008) e pode ser uma opção eficiente para reduzir tempo, trabalho e equipamentos relativos ao fornecimento de suplementos, sem causar I Programa de Pós-graduação em Zootecnia, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil.…”