Interaction of dietary vitamin D3 and sunlight exposure on B. indicus cattle: Animal performance, carcass traits, and meat quality

AbstractAttempts to improve beef tenderness through supplementation with dietary vitamin D3 have been challenged by null results and negative impacts on animal performance and carcass traits. Because vitamin D3 is also synthesised by the animal via ultraviolet radiation from sunlight, the effectiveness of supplementation with dietary vitamin D3 may be modulated by the degree of exposure of the animal to sunlight. Hence, this work aimed to verify whether dietary vitamin D3 modifies meat quality without negatively affecting animal performance and carcass traits in B. indicus beef cattle that were either exposed to or protected from natural sunlight. Forty-two (411±38kg) Nellore-type castrated males were fed a high-concentrate diet for 45days after assignment to a treatment group. The treatments comprised combinations of three levels of vitamin D3 [ViTD — none (V0) or 2×106IU of vitamin D3 administered for either 2 (V2) or 8 (V8) consecutive days pre-slaughter] and two shading conditions (SHADE — unshaded or shaded). The post-mortem (pm) measurements were taken in the Longissimus thoracis et lumborum muscle. The animal performance and carcass traits were unaffected by ViTD or SHADE. The V2 treatment increased the Myofibrillar Fragmentation Index in shaded animals compared to unshaded ones. Animals under shade had higher muscle calcium concentration. There was no effect of either ViTD or SHADE on the shear force. The L* values were higher at 24h pm than at 0 and 1h pm, with no differences among the animals in the ViTD or SHADE groups. Higher a* values were observed among animals in the V8 group than in the V0 group, and higher b* values were observed among animals in the V8 group than in the V2 or V0 groups, which were not different. In conclusion, ViTD and SHADE did not affect animal performance, carcass traits or shear force, whereas animals receiving a lower ViTD dosage and SHADE exhibited altered myofibrillar fragmentation. ViTD affected the colour parameters, and changes in the lightness of the beef related to the time pm were found in meat from animals under SHADE

Production system of pantaneiro horses in the pantanal

This study was conducted in September, 1991 and aimed to describe the production system used by producers of Pantaneiro horses in Pantanal region, Brazil. A standard questionnaire was applied to fifteen producers of different sub regions, focusing different aspects of the production system (administrative, reproductive, nutritional, functional and selection management). Data were grouped and analyzed in accord to management type: extensive and semiextensive. It was observed that although the management system of Pantaneiro horses varied among producers, there were several similar aspects among them. Independently of the management adopted, zoothecnic indices were relatively good, especially fertility rate (80-99 percent), indicating an excellent adaptation of the breed to the natural conditions of the region. In general, the producers of Pantaneiro horses recognize the value of the breed and worry about its conservation, independently of the production system

Production system of pantaneiro horses in the pantanal

This study was conducted in September, 1991 and aimed to describe the production system used by producers of Pantaneiro horses in Pantanal region, Brazil. A standard questionnaire was applied to fifteen producers of different sub regions, focusing different aspects of the production system (administrative, reproductive, nutritional, functional and selection management). Data were grouped and analyzed in accord to management type: extensive and semiextensive. It was observed that although the management system of Pantaneiro horses varied among producers, there were several similar aspects among them. Independently of the management adopted, zoothecnic indices were relatively good, especially fertility rate (80-99 percent), indicating an excellent adaptation of the breed to the natural conditions of the region. In general, the producers of Pantaneiro horses recognize the value of the breed and worry about its conservation, independently of the production system

Hanging the beef carcass by the forequarter to improve tenderness of the Longissimus dorsi and Biceps femoris muscles Suspensão da carcaça pelo dianteiro para melhorar a maciez dos músculos Longissimus dorsi e Biceps femoris

Hanging beef carcasses in different configurations in the cooler affect some carcass muscle tenderness. Forty Nellore steer carcasses (ten per day) were chosen at random in a federally inspected slaughter plant and hanged alternate left and right sides either in the traditional way by the hindquarter (HQ) or by the forequarter (FQ) also called "tenderbife". Carcasses were selected from steers up to 30 months old and had an average hot carcass weight of 244.1 kg. These carcasses were chilled for 48 hours, when samples from the Longissimus dorsi (LD) at the 12th rib and the Biceps femoris (BF) at the P8 site were removed, kept under refrigeration (0-2ºC) for five days and frozen for future analysis. The temperature of the LD after 24 hours taken at the 12th rib was not different for HQ (1.0ºC) and FQ (0.9ºC). Fat thickness measured at the 12th rib was lower (P < 0.05) for HQ (3.8 mm) than FQ (4.3 mm). All samples were thawed during 48 hours under refrigeration for tenderness evaluation. Warner Bratzler Shear force from the LD was lower (P < 0.001) for FQ (3.53 kg) than HQ (4.78 kg) and was not different for BF. Total cooking losses were not different between HQ (19.7%) and FQ (18.9%). Hanging beef carcass by the forequarter caused an improvement in tenderness of the LD without any detrimental effect on the BF (cap of rump).<br>A suspensão da carcaça em diferentes formas na câmara fria influencia a maciez de alguns músculos da carcaça. As carcaças de 40 novilhos Nelore (dez por dia) com no máximo 30 meses de idade foram selecionadas ao acaso em frigorífico (SIF 2543) e lados alternados de suas carcaças foram resfriados e pendurados pelo Tendão de Aquiles do traseiro especial (TA) ou pelo músculo carpo radial dianteiro (DA), também chamado "tenderbife". Todas as carcaças eram de classificação B no Sistema Brasileiro de Tipificação de Carcaças, com média de peso de carcaça quente de 244,1 kg. O pH 24 horas não diferiu para os tratamentos, (TA = 5,69 e DA = 5,70). As carcaças foram resfriadas por 48 horas e a seguir, amostras do Longissimus dorsi (LD) na altura da 12ª costela e Biceps femoris (BF) na altura do sítio P8 foram removidas, mantidas sob refrigeração (0-2ºC) por mais 5 dias e a seguir congeladas para posterior análises. A espessura de gordura medida na altura da 12ª costela foi menor (P < 0,05) para TA (3,8 mm) do que DA (4,3 mm). A força de cisalhamento do músculo LD foi menor (P < 0,01) para o DA (3,53 kg) do que para o TA (4,78 kg) e não foi estatisticamente diferente para o músculo BF. As perdas totais ao cozimento também não foram estatisticamente diferentes (TA = 19,7% e DA = 18,9%). O resfriamento da carcaça pendurada pelo dianteiro ocasionou uma melhoria significativa na maciez do músculo LD (contra-filé) sem causar um efeito indesejável no músculo BF (picanha)