Performance and carcass traits of Santa Inês lambs finished with different sources of forage

Abstract

-The objective of this study was to evaluate performance and biometrics of lambs fed different sources of forage. Twenty-four six-month-old Santa Inês female lambs were randomly allocated to four experimental diets and housed in individual stalls. They weighed on average 26.35±0.20 kg. The diets were coast cross hay (HAY), cassava hay (CAS), dehydrated by-product of pea crop (PEA) and saccharin (SAC). The diets were formulated with the same amount of protein and energy with fixed levels of forage (60%) and concentrate (40%). Adaptation to the diet took 7 days, with 45 days on experiment. Weights and biometric measurements were obtained every fortnight and feed intake three times a week. Rights half-carcasses were weighed and sectioned into retail cuts, rib, loin, shoulder, belly, neck and leg, which were weighed individually. Weight gain in lambs was significantly different between diets, with those fed saccharin gaining more. Overall, treatments did not significantly affect biometric measurements. There was a significant difference for feed intake and live weight at the end of the experiment. Animals fed PEA and SAC showed the best results. Average positive correlations were found between biometric measurements and live weight. Treatment PEA had heavier hot (14.36 kg) and cold (14.01 kg) carcass weights than the other groups. Hot carcass kill-out was higher for animals fed PEA as well as ham weight, belly, neck and heart girth. The weight of the abdominal viscera (%) for lambs fed CAS was greater than those fed SAC and PEA. The weights of the thoracic viscera as well as the liver, for lambs fed PEA were higher. The by-product of pea yielded best results, followed by saccharin, and can replace traditional forage sources in the region, providing similar results in terms of cuts and body components. These could be an alternative for feeding sheep in the dry season. The substitution of forages using by-product of pea and saccharin led to improved productivity over the coast-cross hay available in the Federal District -Brazil.

Carcass characteristics and fatty acid profile of Santa Inês lamb fed banana leftovers

“…It was observed that animals which had a higher final body weight tended to record higher weights for the commercial cuts (leg, shoulder, neck, belly), as expected. This result agrees with Menezes et al (2013) who demonstrated that carcass yield increased with body weight. However, the development of organs showed different growth stages, as each animal reached maturity at different physiological ages (Carvalho et al, 2016).…”

“…The weight loss by cooling (2 %) was not affected by the diet and was similar to those observed by other authors working with alternative foods for sheep (Menezes et al, 2013). Overall, subcutaneous fat deposition (average of 2.97 mm) did not differ in lambs fed different dietary treatments.…”

“…Brazilian agriculture hits record production levels every year, generating an increasing quantity of agricultural residues and agroindustrial byproducts with high potential for use in ruminant feed (Menezes et al, 2013). This includes leftovers from the horticulture and fruticulture sectors.…”

Productive characteristics of feedlot Santa Inês and Dorper lambs: intake, digestibility, feeding behavior, performance, carcass traits, and meat quality

“…As there were no differences in nutrient digestibility between genetic groups, the higher rumination efficiency observed in Santa Inês lambs is probably due to anatomical and/or physiological differences between genetic groups. Considering that the ruminal passage rate is higher in Dorper (Moyo and Nsahlai 2018) and lower in Santa Inês lambs (Menezes et al 2013), the latter needs to ruminate a higher amount of material to be able to empty the rumen, resulting in a higher amount of dry matter ruminated per unit of time. Furthermore, the trend on PC digestibility probably is the result of a more efficient ruminal microbiota in Santa Inês lambs.…”