Fish-meal supplement for severely undernourished ewes: effects on apparent digestibility and utilization of the diet

Abstract

Link to this article: http://journals.cambridge.org/abstract_S0003356100007169How to cite this article: P. Kabré and M. Petit (1994). Fish-meal supplement for severely undernourished ewes: effects on apparent digestibility and utilization of the diet. AbstractEight non-pregnant, non-lactating adult ewes weighing 56 kg were fed for 26 days on a meadow hay (organic matter 937 g, crude protein 107 g, metabolizable energy (ME) 8-3 M] per kg dry matter) to satisfy half of their daily energy and protein maintenance requirements i.e. 200 kj ME and 1-3 g truly digestible protein per kg M 0 ' 75 . They were then allotted to two groups of four each. Control ewes continued to receive the initial diet for another 74 days while the others were supplemented with 60 g/day fish meal to receive 200 kj ME and 2-7 g truly digestible protein per kg initial M 0 ' 75 per day. In spite of its high nitrogen content, the digestibility of the hay was increased by the protein supplementation, e.g. from 0-56 to 0-60 for neutral-detergent fibre and from 0-54 to 0-59 for energy. The supplemented ewes lost significantly less body weight than the controls (96 v. 134 g/day) essentially because of their higher ME intake (272 v. 252 kj/kg average M 0 ' 75 during the experimental period). The measurements of blood metabolites suggest that the daily amounts of mobilized body protein increased with duration of underfeeding. The additional amino acids provided by fish meal were principally used as a source of energy and for wool growth.

Effects of a high-protein, low-energy diet in finishing lambs: 1. Feed intake, estimated nutrient uptake, and levels of plasma metabolites and metabolic hormones

“…Galbraith et al (1997) observed higher levels of NEFA for the unsupplemented treatment compared to fish meal supplementation. Kabré and Petit (1994) found NEFA levels of approximately 1.1 AEq/100 ml plasma for both supplemented and unsupplemented lambs, which would correspond to the values observed for treatment CON in the present experiment. However, the feed restriction period in that study was longer, and experimental lambs where in medium body condition at the beginning of that study.…”

“…1C), which are about 50% higher than values reported by Kabré and Petit (1994) for ewes in negative energy balance. Diet SFM produced the numerically highest levels.…”

“…Ortigues et al (1990) and Kabré and Petit (1994) also found that fish meal supplementation significantly increased digestibility of a medium quality roughage under restricted intake levels. However, our values are considerably greater than the 43% reported by NRC (1985) for barley straw.…”

“…However, when the base diet was fed at high levels, plasma glucose levels were highest at low levels of fish meal supplementation. Kabré and Petit (1994) reported mean glucose values of 61.4 mg/100 ml for unsupplemented, and 60.9 mg/ 100 ml for fish-meal supplemented ewes in negative energy balance, i.e. no potential net effect of fish meal on circulating glucose.…”

“…Hvelplund and Madsen (1990) proposed to calculate degradability from protein solubility in a buffer solution. Kabré and Petit (1994) used this equation in a modified form for the estimation of fish meal degradability in an experimental setting similar to this study. More commonly, degradability of protein supplements is estimated with the two-phase exponential decay process proposed by Ørskov and McDonald (1979).…”