Effects of maturity of silage and protein content of concentrates on milk production of ewes rearing twin or triplet lambs

Abstract

. 1999. Effects of maturity of silage and protein content of concentrates on milk production of ewes rearing twin or triplet lambs. Can. J. Anim. Sci. 79: 499-508. Fifty-one Outaouais Arcott ewes were used to study the effects of silage maturity, protein level and number of lambs suckled on milk production and lamb growth in a 2 × 2 × 2 factorial design experiment. Ewes were given ad libitum access to either an early-bloom (EB) or full-bloom (FB) bromegrass silage supplemented with 725 g d -1 of a 15 or 21% CP concentrate. Number of lambs suckled were two or three per ewe. During the 6 wk of lactation, ewes receiving the EB silages consumed more DM (2.07 vs. 1.74 kg d -1 , P < 0.01), and gained more (1.3 and -2.7 kg, P < 0.05) than ewes fed FB. Ewes that raised three lambs had greater silage intake (2.00 vs 1.86 kg d -1 ) and lost more weight during lactation (-2.8 vs. +0.3 kg) than those suckling twins. Milk yields of ewes offered the EB and FB silages were 2.42 and 2.28 kg d -1 , respectively (P < 0.05), for the first 4 wk of lactation. Ewes that raised three lambs produced less milk (2.25 vs. 2.43 kg d -1 ) than those nursing twins (P < 0.05). Milk fat content (8.2%) was not influenced by treatments, whereas milk protein content was higher (P < 0.05) from ewes receiving the EB silage compared with the FB silage (5.05 vs. 4.76%). At 4 and 6 wk of age, twin lambs were 2.6 kg (9.5 vs. 6.9 kg) and 3.5 kg (12.0 vs. 8.5 kg) heavier (P < 0.01) than triplet lambs for EB and FB silages, respectively. However, at the end of the 6-wk period, ewes nursing triplets weaned 1.3 kg more lambs than did ewes nursing twins (P < 0.05). Lambs from ewes that received the EB silage were 1.1 kg heavier at 6 wk (P < 0.05) than those from ewes fed with the FB silage. Also, lambs from ewes receiving the 21% CP concentrate were 1.1 kg heavier at 6 wk (P < 0.05) than the lambs from ewes fed the 15% CP. Litters were heavier at 6 wk with 21% CP concentrate compared with 15% (25.1 vs. 24.1 kg, P < 0.05), and triplet litters were heavier (P < 0.01) than twin with the EB silage. Within litter weight variation (weight difference between the biggest and the smallest lambs in a litter) proved to be greater (P < 0.05) with triplets (4.2 kg) than twins (2.2 kg). In conclusion, providing a higher quality silage (lower ADF and higher CP contents) improved ewe feed intake, milk production, lamb growth and litter weight, while feeding a higher protein concentrate only improved lamb growth with the lower quality silage.Key words: Ewe, lamb, growth, milk production, silage, protein, triplet Roy, A., Laforest, J. P., Castonguay, F. et Brisson, G. J. 1999. Effets de la maturité de l'ensilage et du niveau de protéines du supplément sur la production laitière de brebis allaitant deux ou trois agneaux. Can. J. Anim. Sci. 79: 499-508.Cinquante et une brebis Arcott Outaouais ont été utilisées dans une étude factorielle 2 × 2 × 2 sur les effets de la maturité de l'ensilage, du niveau de protéines du supplément et du nombre d'agneaux allaités sur la production l...

Triplet lambs and their dams – a review of current knowledge and management systems

“…Gallo and Davies (1991) reported that in the first month of lactation intakes of triplet-bearing ewes rearing either two or three lambs did not differ. Combined these results indicate that a triplet-rearing ewe is more likely to be under nutritional stress in lactation than twin rearing ewes and therefore it is not surprising that triplet-rearing ewes lose more body condition (Gallo and Davies 1988;Roy et al 1999;Alexandre et al 2001;Kenyon et al 2010a;Hutton et al 2011). Further, Kenyon et al (2013) noted that triplet dams rearing a full set of triplets had lower body condition and live weight at weaning than a ewe rearing only one or two of their triplet lambs.…”

“…In addition, the number of lambs weaned within a triplet set can negatively affect individual lamb weaning weights (Table 4), although total weaning weight of a litter is highest when all three lambs are weaned. There is greater variation in litter weaning weight in triplets than twins (Roy et al 1999). Further, Kenyon and Blair (2014) and Gholizadeh and Ghafouri-Kesbi (2015) reported that triplets can be lighter than singletons and twins to at least one year of age.…”

“…This was likely not surprising given the lack of difference in crude protein and total dry matter intake of the supplements. While Roy et al (1999) reported that offering a higher crude protein supplement (21% vs. 15%) in both late pregnancy and lactation to ewes with unrestricted access to two types of brome grass silage, had no effect on milk production. However, the silage type with the higher metabolisable energy and crude protein and lower fibre concentration, resulted in greater ewe intakes and milk production.…”

“…However, the impacts of pregnancy nutrition when ewe intake in lactation is restricted appears to not have been investigated and should be. Roy et al (1999) reported that offering a higher crude protein supplement in both late pregnancy and in lactation to ewes offered unrestricted brome grass silage increased lamb live weight in mid-to late-lactation. While Davies and Gallo (1988) found that offering higher levels of protein in a complete diet, under unrestricted feeding conditions in lactation, increased lamb growth to weaning.…”

Okara as a protein supplement affects feed intake and milk composition of ewes and growth performance of lambs

“…Percentage of protein in milk did not follow this trend and was also not significantly different among the 4 diets. Milk protein content was shown in one study not to be affected by crude protein concentration in the feed consumed by ewes ( Roy et al., 1999 ). There was not a significant difference in milk urea nitrogen (MUN) concentration among the different diets ( P > 0.05), but there was a trend for diets with grass hay as the forage to have higher MUN.…”