Effects of supplementation with digestible undegradable protein in late pregnancy on ewe colostrums production and lamb output to weaning

Abstract

The aim of this study was to investigate the effects of supplementation with digestible undegradable protein (DUP) in diet during late pregnancy on colostrum production, lamb survival and growth. For 3 weeks prior to lambing, 41 Afshari ewes were assigned at random to three dietary treatments, namely a control (CDUP), moderate (MDUP) and high (HDUP) DUP group. The ewes (n = 14) in CDUP group were fed a protein maintenance level for pregnant ewes [83 g metabolizable protein (MP)/kg dry matter (DM)], while ewes in the MDUP (n = 13) and HDUP (n = 14) groups were fed diets provided 14% (94.7 g MP/kg DM) and 24% (104.3 g MP/kg DM) MP in excess of these requirements respectively, which this increment was coming from DUP (DUP/MP ratio 43.8; 51.0% and 57.6% respectively). All diets were isoenergetic (12 MJ ME/kg DM). All ewes received the same lactation diet after lambing. Ewes in HDUP tend to produce more colostrums (p < 0.1) and had higher protein, fat, and solids non-fat content (p < 0.05) in colostrums during the first 24 h after lambing. MDUP group had higher colostrum yield compared to CDUP (p < 0.1). The changes in body weight and body condition score of ewes were similar for all diets but placenta weight was higher in MDUP group (p < 0.05) than for HDUP and CDUP ewes. Lamb body weight at weaning was higher for males compared to females (p < 0.05), but was not different between treatments. HDUP ewes had higher blood glucose concentration in the pre-lambing period than other treatments (p < 0.05). In this period, increasing the level of DUP in diet increased the content of blood urea nitrogen (p < 0.05). It was concluded that increasing the DUP content of diet for 3 weeks prior to lambing above the standard requirements resulted in an increase in colostrums production but had no effect on lamb outcome to weaning.

Supplementing metabolizable protein to ewes during late gestation: I. Effects on ewe performance and offspring performance from birth to weaning1

“…This is contrary to the results observed in yr 1 of the current study, in which there was no difference in gestation length due to the MP intake of the dam during late gestation. Similar to our results, Amanlou et al (2011) reported that gestation length was not altered by maternal MP supplementation in ewes during late gestation. Gestation length could not be measured accurately in yr 2 due to the lack of breeding mark observations on a daily basis.…”

“…Calves born to cows that were supplemented with CP during late gestation were heavier at weaning than calves born to cows that were not supplemented (Stalker et al, 2006). However, Amanlou et al (2011) observed no effects of maternal MP supplementation (114 and 124% of MP requirements) on lamb weaning BW. Although there was a tendency for weaning weights to be linearly increased as MP in the diet increased, this tendency was not observed in yr 2.…”

“…Wang et al (2007) observed a linear increase in milk production of dairy cows as MP in the diet was increased linearly from 8.2 to 10.3% MP (% of DM). Additionally, Amanlou et al (2011) observed a tendency for increased colostrum yield with increased MP supplementation at 114 and 124% of requirements. The MP absorbed by the dam may have been shuttled to the mammary gland to enhance colostrum production.…”

“…Similarly, calf birth weight was not affected when cows were supplemented with CP during the last 78 d of gestation compared with calves born to cows that were not supplemented with CP (Bond and Wiltbank, 1970), suggesting that protein intake during late gestation may not alter birth weights. Moreover, Amanlou et al (2011) also observed no effects of maternal MP supplementation on lamb birth weight. McNeill et al (1997) suggested that ewes consuming a low CP diet (81 g/d) were more efficient than ewes consuming a high CP diet (215 g/d), which was attributed to increased efficiency in the recycling of urea and a reduction in hepatic catabolism of AA.…”

“…The MP absorbed by the dam may have been shuttled to the mammary gland to enhance colostrum production. Ewes consuming increased MP during late gestation had increased protein, fat, and solids-not-fat (substances other than butterfat and water) in colostrum (Amanlou et al, 2011), which may have improved colostrum quality. When cows were supplemented immediately postpartum with either 100 or 150% of CP requirements and either high or low escape CP, there was no effect on milk yield (Rusche et al, 1993).…”