Effect of increasing degradable intake protein on intake and digestion of low-quality, tallgrass-prairie forage by beef cows.

Abstract

Five ruminally and duodenally fistulated Angus x Hereford cows were used in a 5 x 5 Latin square to monitor intake, ruminal fermentation responses, and site and extent of digestion associated with providing increasing amounts of supplemental degradable intake protein (DIP). Cows had ad libitum access to low-quality, tallgrass-prairie forage (1.9% CP, 77% NDF) that was fed twice daily. The supplemental DIP (sodium caseinate; 90% CP) was infused intraruminally at 0630 and 1830 immediately before feeding forage. Levels of DIP were 0, 180, 360, 540, and 720 g/d. Each period consisted of 14 d of adaptation and 6 d of sampling. Forage OM intake increased quadratically (P < .01) with increasing supplemental DIP reaching a peak at the 540 g/d level. True ruminal OM and NDF digestion increased with the addition of 180 g/d supplemental DIP, but exhibited only moderate and somewhat variable responses when greater amounts of supplemental DIP were infused (cubic, P < or = .03). Microbial N flow and efficiency increased linearly (P < .01) with increasing supplemental DIP. However, a quadratic effect (P < .01) was observed for total duodenal N flow, which was maximized at 540 g/d supplemental DIP. A linear (P = .02) treatment effect was observed for ruminal fluid dilution rate. Total ruminal VFA and ammonia concentrations increased (P < .01) in response to DIP supplementation. In conclusion, increasing supplemental DIP generally improved forage utilization; intake of digestible OM was maximized when it contained approximately 11% DIP.

Induction of low-nutritious food intake by subsequent nutrient supplementation in sheep (Ovis aries)

“…Hedonic and post-ingestive processes might have interacted in determining the intake level of oat hay. Indeed, under present levels of supplementation, soya bean meal has been shown to benefit fibre digestion to a larger extent than ground corn (Matejovsky and Sanson, 1995;Koster et al, 1996;Moore et al, 1999). However, this idea needs further testing.…”

Effects of protein and energy supplementation on growth, forage intake, forage digestion and nitrogen balance in meat goat kids

“…Dietary energy and protein supplements could be used to increase the productivity of hay-fed goats. Protein supplements increase intake and utilization of low-quality forages in cattle (Kö ster et al, 1996), as do high-protein concentrates (Negesse et al, 2001) and leguminous forage (Osuji and Odenyo, 1997) supplementation to goats. However, it has been shown that protein supplements have little effect on feed intake of cattle consuming forages with CP concentrations above approximately 6% (Mathis et al, 2000).…”

Consumo e digestibilidade de feno de baixa qualidade suplementado com nitrogênio não protéico em bovinos

“…O CMOD apresentou comportamento quadrático, em relação ao nível de inclusão de uréia ao suplemento (CMOD = -12,02x 2 + 18,574x + 35,836, r 2 = 0,3403) (Tabela 5). O ajuste matemático dos dados obtidos mostrou que a inclusão de uréia, em quantidade equivalente a 0,77 g UTM -1 , propiciou consumo de MOD de 43 g UTM -1 , valor intermediário entre os máximos encontrados por Koster et al (1996) e Mathis et al (2000, que foram 37,4 e 58,1 g UTM -1 , respectivamente.…”

“…As relações de CPDR:CMOD estão dentro das propostas pelo National Research Council (1996), que variam de 7 a 13 para volumosos de baixa qualidade. Koster et al (1996) e Cochran et al (1998) relataram que a exigência de proteína degradável no rúmen, para a otimização do ambiente ruminal, pode ser obtida pela PDR, que maximiza o consumo de matéria orgâni-ca digestível. Isto é possível depois do ajuste da equação quadrática da relação entre CPDR e o CMOD e o cálculo do ponto máximo da curva.…”