Early weaning and concentrate supplementation strategies for lamb production on Tifton-85 pasture

Abstract

-The influence of early weaning and concentrate supplementation strategies on sward characteristics, forage chemical composition and lamb productivity were evaluated in four production systems on Tifton-85 pasture: suckling lambs not supplemented until slaughter; suckling lambs supplemented with concentrate in creep feeding until slaughter; early-weaned lambs not supplemented until slaughter; and early-weaned lambs supplemented with concentrate until slaughter. Structural, morphological and productive characteristics of pasture were measured. The forage was chemically analyzed to estimate its composition. Lambs average daily gain and productivity were calculated. Sward height, forage and morphological components mass were lower in systems without weaning. Forage production was higher in systems with supplementation. Higher levels of neutral and acid detergent fiber were observed in forage ingested by lambs in creep feeding and by weaned and unsupplemented lambs. Average daily gain was higher for lambs in creep feeding (275 g/d) and lower for the weaned and unsupplemented animals (57 g/d). Productivity was higher for weaned and supplemented lambs (21 kg lamb body weight, BW gain/ha/d). Lower productivity was observed in systems without supplementation (5 kg lamb BW gain/ha/d on average). Ewes modify the sward conditions improving the pasture characteristics and the quality of forage produced. Changes in sward conditions affect the chemical composition of forage ingested by lambs. Early weaning may be an alternative to maximize pasture utilization in small areas. Concentrate supplementation may increase lamb performance and productivity in grazing systems. If the objective is to improve lamb individual performance, creep feeding should be used.

Maternal supplementation of twin bearing ewes with calcium and magnesium alters immune status and weight gain of their lambs

“…Lighter weaning weight of lambs makes mating management of hoggets difficult ( Kenyon, Morel & Morris, 2004 ). Moreover, early weaning gives ewes a greater period to rest and recover their body condition ( Arnold, Wallace & Maller, 1979 ; Lee, Majluf & Gordon, 1991 ; Silva et al., 2014 ) which may be a good strategy to increase reproductive performance of ewes.…”

Management Strategies for Lamb Production on Pasture-Based Systems in Subtropical Regions: A Review

“…We did not find a performance difference between supplemented and control animals, concluding that the nutrients provided by the pasture and the lactating ewes were sufficient to keep lambs at performance levels equivalent to lambs supplemented at 1% LW. Subsequent studies (11,20,21) indicated that, in that type of pasture, lamb supplement must be above 2% LW to induce measurable differences vis-á-vis control animals.…”

Weaning and concentrate supplementation on the characteristics of carcass cuts and longissimus muscle of Suffolk lambs finished on pasture

“…Therefore, this strategy allows an early return of ewes to cyclicity, reducing the interval between parturitions, and increasing the rate of lambs produced per ewe year -1 (Oliveira et al, 2014). When weaning is associated with concentrate supplementation offered after weaning, the main results obtained are increased individual performance (Souza et al, 2010;Geron, Mexia, Garcia, Silva, & Zeoula, 2012) and lamb stocking rate on pasture (Carvalho et al, 2006;Silva et al, 2014). Use of forage grasses such as Tifton 85 (Cynodon spp.)…”

“…In addition, concentrate supplementation may be necessary to meet the nutritional requirements of breeds specialized for meat production, such as Suffolk, allowing these animals to express their growth potential under grazing conditions. Studies performed in the Brazilian subtropical region showed that Suffolk lambs finished at 32-37 kg of body weight (BW) on Tifton 85 pasture presented an average daily gain of 135 -280 g day -1 in systems without weaning; 50 -110 g day -1 in systems with weaning and without supplementation; and around 150 g day -1 when they received concentrate supplementation post-weaning (Silva et al, 2014;Poli et al, 2020). In systems without weaning, the proteinenergy supplementation offered in creep feeding has been widely used to improve lambs' growth, resulting in…”