Comportamento Ingestivo De Novilhos Mestiços Terminados Em Confinamento Alimentados Com Borra De Soja

Abstract

Resumo Este trabalho objetivou avaliar os efeitos da inclusão da borra de soja no comportamento ingestivo de 30 novilhos mestiços Charolês/Nelore, confinados, com 20 meses de idade e peso médio inicial de 328,3 kg. Cada grupo experimental foi composto por seis animais, distribuídos nos tratamentos: 00; 30; 60; 90 e 120 g de borra de soja por 1000 g de matéria seca na dieta, os quais continham 29,0; 47,3; 66,7; 86,8 e 106,8 g de extrato etéreo, respectivamente. O aumento no nível de inclusão de borra de soja na dieta não interferiu no tempo de alimentação, ruminação e ócio (3,11; 13,33 e 7,55 h, respectivamente). As variáveis número de mastigações por bolo, tempo de mastigação por bolo, número de bolos, número de mastigações diárias e tempo de mastigação total (h/dia) (62; 58; 470; 28978 e 10,65, respectivamente) também não sofreram efeito dos tratamentos. O consumo de matéria seca foi similar, em contrapartida, o consumo de fibra detergente neutro (kg/dia) e a eficiência (g FDN/h) da referida fração apresentaram comportamento linear decrescente com aumento da inclusão de borra. A borra de soja pode ser incluída na dieta de novilhos mestiços confinados até o nível de 120 g por 1000 g de matéria seca sem que haja efeitos negativos sobre as principais variáveis relativas ao comportamento ingestivo.

Soybean hulls and / or white oat grains on the ingestive behavior of confined steers

“…Animals fed diet containing soybean hulls and white oat grains had a lower total rumination time when compared to animals fed only soybean hulls or white oat grains. A correlation between rumination time and NDF content (r = −0.42; P = 0.02) was obtained by Callegaro et al (2018) when assessing soybean soapstock inclusion levels in the diet (0-12%), a result different from that obtained in this study. The authors attributed this correlation by the lack of physically effective fiber provided by the ingredient soybean hulls.…”

“…Throughout the day, animals fed diet mixture spent less time chewing food when compared to the diets with white oat grains and soybean hulls, which did not differ significantly from each other. Different from that obtained in this study, Callegaro et al (2018) stated that the higher the energy density of the diet and the lower the NDF content are, animals perform a lower number of chews per bolus and ruminate lower regurgitated bolus per day. Pereira et al (2007) studied the ingestive behavior at different levels of diet neutral detergent fiber and found that its increase from 30 to 60% increased the number of chews per bolus, the number of bolus per day and, consequently, the number of chews per day and the total chewing time.…”

“…Meals are usually concentrated near feeding times, which were at 8 and 14 h in this study (Figure 1). In a study with similar feeding times, Freitas et al (2010) and Callegaro et al (2018) verified a higher presence in times close to feeding and at dusk when assessing the presence of animals in the feeding trough. Animals were conditioned to the management routine.…”

“…The daily food intake is obtained from the number of meals consumed per day, their duration, and animal feeding rate, which is represented by the speed at which each meal is performed (CARVALHO et al, 2008). According to Callegaro et al (2018), the shorter the time and the distance traveled in the bays, the higher the energy available for muscle development and fat deposition in the carcass. Meals are usually concentrated near feeding times, which were at 8 and 14 h in this study (Figure 1).…”

“…Animals were conditioned to the management routine. The presence of animals in the trough at 16-18 h is due to the mild ambient temperature, thus stimulating feeding (CALLEGARO et al, 2018). The mean time per meal was also different between the three diets, with the longest period for the diet containing white oat grains, followed by mixture and soybean hulls.…”