NR 27. Strategic nutritional management technologies for enhancing forage beef production in the tropical venezuelan llanos

The response in growth and carcass quality of 102 intact and 20 castrate males grazing dry season followed by irrigated dry season native (Lambedora) improved (Tanner grass) forages to selected strategic technologies was investigated. The key is to develop strategies to deliver these technologies in ways that will enhance fermentative rate and efficiency to allow greater intake and animal productivity. Nutritional strategies included 1) a macro/tracemineral supplement (MIN) or 2) a strategic (STRAT) supplement including key minerals, a slowly degrading protein source (feather meal) to provide a continuous nitrogen release, ionophore (Salocin), degradable fiber (rice polishings), and capsulized fat (whole cottonseed). Cattle initially were intensively grazed on flood and pump irrigated pastures until target weight (average 495 kg) and condition were achieved. Cattle were implanted initially with zeranol (72 mg) or Revalor followed by a second implant of zeranol (72 mg). Mineral supplement for MIN cattle was provided continuously and STRAT (comprised of feather meal, whole cottonseed, molasses, rice polishings, mineral mix and Salocin at 10, 0, 5, 77.9, 7, and 1 % for d 0-60 and 10, 49.9, 5, 28, 7, and 1 % for d 61-182), was hand-fed at 1 kg/hd daily. Total MIN or STRAT consumption was 15.3 vs. 172 kg/hd or 84 vs. 945 g/d through d 182. At 182 d, the first group was selected for slaughter and supplementation with STRAT was ceased. At this point, the MIN and STRAT cattle averaged 459.4 and 487.2 kg and differed (P<.001) in weight. Average daily gain to 182 d averaged 676 vs. 818 g (P<.001), for a 142 g/d response. Further, the STRAT supplement enhanced (P<.001) dressing percentage from 57.6 to 59.0 % at termination, and adjustment of d 182 response to a common dressing percentage yielded a 32.6 kg response in weight or 179 g response in daily gain

Comparación de machos enteros búfalos de agua (Bubalus bubalis) vs vacunos acebuados en características al sacrificio, de la canal, rendimiento carnicero y palatabilidad del longissimus. (Comparison of water buffalo (Bubalus bubalis) vs Zebu-type intact males bovines in slaughter characteristics, carcass traits, cutability and longissimus palatability)

Twenty-seven intact male water buffaloes of Murrah breeding (BUFFALOES) and 18 Zebu type bulls (CATTLE) were savannah-fed on the same ranch and slaughtered when they reached a desirable conformation to be compared in slaughter characteristics, carcass traits, cutability and meat palatability. Slaughter weight ranged 435 to 512kg for BUFFALOES and 375 to 494kg for CATTLE. Least square mean differences between species in percent head, cooler shrink, feet, blood and genitals were not significant (P>.05). BUFFALOES had significantly heavier hides, larger gastrointestinal tract and higher (P>.05) percentages of liveweight removed as organ fat. These body components are partly responsible for the significantly lower dressing percentages (- 6.5 %) of BUFFALOES vs CATTLE. Non-significant differences were found between species for total percentages of trimmed fat and bone, and percent yield (P>.05) of the most expensive (high valued, boneless) cuts. CATTLE yielded higher percentages (P<.05) of the medium-valued cuts (+1.39%) and the composite group of boneless (high and medium valued) cuts (+2.06%); whereas buffaloes exceeded (+.86%) cattle in the proportion of low-valued cuts (P<.05). Significant Specie x Carcass weight interactions were detected for some retail components. Longissimus steaks from CATTLE exhibited higher (P<.001) shear values (5.05kg vs 3.52kg) (P.05) overall tenderness ratings (4..3 vs 4.8). It was concluded that commercial disadvantages of BUFFALOES in dressing percent and cutability detected herein, could be overcome by designing marketing strategies promoting the buffalo meat as a high-quality product

Rasgos de crecimiento y pesos en canal de toros Brahman puros y F1 Brahman x Bos taurus criados y cebados semi-intensivamente en sabana mejorada (Growth traits and carcass weights of purebred Brahman and F1 Brahman x Bos taurus bulls raised and fattened semi-intensively on improved savannah)

To explore differences in growth traits, carcass weights and dressings percentages under improved, savannah-rearing conditions, five breed groups (purebred Brahman, PUREBREDS; F1 Angus, F1ANG; F1 Chianina, F1CHIA; F1 Romosinuano, F1ROMO; and F1 Simmental, F1SIM) of 10 contemporaneous bull calves each, were raised and fattened semi-intensively as a whole grazing lot. Data were analyzed for variance-covariance, using initial liveweight at each growth period, as a covariate. Adjusted daily gains (ADG) from birth to weaning for F1ANG, F1CHIA and F1ROMO outweighed (> 77g/d; P<.05) that of PUREBREDS. From weaning time up to 18m of age, F1ROMO and F1SIM outweighed PUREBREDS in ADG (> 62g/d; P<.05). F1 bulls were heavier than PUREBREDS at weaning and 18m, showing, respectively, differences of 20.4kg (11.5%; P=.10) and 20.6kg (9.5%; P=.0001). From 18m up to initiation of the fattening period (FATINITIATION, circa 23m of age), PUREBREDS and F1ANG surpassed in ADG (> 80g/d; P<.05) the remaining groups. Nevertheless, breed groups did not vary significantly (P>.05) in FATINITIATION weights, fattening rates, and time of feeding. At the endpoint used herein, PUREBREDS and F1 bulls did not differ in slaughter age, carcass weight or dressing percentage (P> .05). Under improved savannah feeding and management conditions, as described for this particular operation, crossbreeding allows product diversification of traditional Brahman cow-calf production systems by raising and/or fattening F1 young (<28m of age) slaughter bulls

Trace element distribution in selected edible tissues of Zebu (Bos indicus) cattle slaughtered at Jimma, SW Ethiopia

The amount of trace elements present in edible bovine tissues is of importance for both animal health and human nutrition. This study presents data on trace element concentrations in semitendinosus and cardiac muscles, livers and kidneys of 60 zebu (Bos indicus) bulls, sampled at Jimma, Ethiopia. From 28 of these bulls, blood samples were also obtained. Deficient levels of copper were found in plasma, livers, kidneys and semitendinosus muscles. Suboptimal selenium concentrations were found in plasma and semitendinosus muscles. Semitendinosus muscles contained high iron concentrations. Trace elements were mainly stored in the liver, except for iron and selenium. Cardiac muscles generally contained higher concentrations of trace elements than semitendinous muscles except for zinc. A strong association was found between liver and kidney concentrations of copper, iron, cobalt and molybdenum. Liver storage was well correlated with storage in semitendinosus muscle for selenium and with cardiac muscle for cobalt and selenium. Plasma concentrations of copper, selenium, cobalt were well related with their respective liver concentrations and for cobalt and selenium, also with cardiac muscle concentrations. The data suggest multiple trace element deficiencies in zebu cattle in South-West Ethiopia, with lowered tissue concentrations as a consequence. Based on the comparison of our data with other literature, trace element concentrations in selected edible tissues of Bos indicus seem quite similar to those in Bos taurus. However, tissue threshold values for deficiency in Bos taurus cattle need to be refined and their applicability for Bos indicus cattle needs to be evaluated

Muscle lipid composition in bulls from 15 European breeds

Cattle meat provides essential nutrients necessary for a balanced diet and health preservation. Besides nutritional quality, consumers' preferences are related to specific attributes such as tenderness, taste and flavour. The present study characterizes the fatty acid composition of beef, which is an important factor in both nutritional and quality values, in 15 European cattle breeds fed a similar diet and reared in five countries (United Kingdom, Denmark, France, Italy and Spain). The effect of possible slight differences on diet composition which might have occurred between countries were included in the breed effect which confounds country, diet, slaughter house and slaughter day as all individuals of a same breed were managed simultaneously. The wide range of breeds studied and the significant differences on lipid profile described here provide a broad characterization of beef meat, which allows giving a better response to the variety of consumers' preferences. Regarding meat health benefits, the groups that stand out are: the double-muscled animals, which displayed lower total fat, lower proportion of saturated (SFA) and monounsaturated (MUFA) fatty acids, and a higher proportion of polyunsaturated (PUFA) fatty acids; and Limousin and Charolais breeds with a significantly higher conversion of 18:3n-3 PUFA to the long chain 22:6n-3 PUFA