Marcela Abbado Neres

Forma física da ração e pesos de abate nas características de carcaça de cordeiros em creep feeding

Twenty 3/4 Suffolk male lambs were fed ground and pelleted diets and slaughtered at 26 and 28 kg of liveweight. Diets were isoprotein (21% CP) and isoenergetic (2.9 Mcal ME/kg DM). Lambs had free entrance on creep feeding, staying with their mothers until reaching slaughter weight. Pelleted diet resulted in higher hot dressing-out percentages (54.18% for pelleted diet and 52.04% for ground one) and higher true dressing-out percentages (58.37% for pelleted diet and 56.66% for ground one). Hot and cold dressing-out percentages were not affected by final liveweight (12.79 and 13.05 kg for 26 and 28 kg slaughter live weight, respectively). Diet physical form and final live weight did not affect Longissimus muscle area and length. Loin width and maximal fat depth were higher for lambs fed pelleted diet and minimum fat depth was lower for lambs slaughtered at 26 kg of live weight (1.48 and 1.77 cm for lambs slaughtered at 26 and 28 kg, respectively). It was concluded that pelleted diets provided better hot carcass and biological dressing-out percentages and loin depth and compactness carcass index. Live weight of 26 kg was considered the most useful for lambs slaughter because presented similar carcass traits compared to 28 kg.

Medidas objetivas e composição tecidual da carcaça de cordeiros alimentados com diferentes níveis de energia em creep feeding

ABSTRACT - The experiment was carried out at Sheep Production Department, Universidade de Marilia-SP, to evaluate the effectof energy levels (2.6, 2.8 and 3.0 Mcal ME/kg DM) on objective measures of carcasses and loin, cuts weight and yield and tissuecomposition and muscularity of carcasses of lambs under creep feeding. Isoprotein rations (18.50 %CP) were fed ad libitum , twice aday. Lambs stayed with their dams until slaughter weight ( 31 kg). After, lambs were fasted, when slaughter live weight was recoded .During cooling at 5 o C by 24 h, carcasses were hanged by tarse-metartase articulation, distanced by 17 cm, and, then, were measured.Later, carcasses were sectioned and the left side was divided in seven anatomical parts (shoulder, leg, loin, true ribs, false ribs, breastpoint and neck) to calculate weight and yield of cuts. Then, muscle Longissimus dorsi was evaluated. Left leg was dissected and it wasconsidered muscle, fat and bone weights. Muscularity index was figured out. Results showed significant differences for thorax depth,true ribs weight and yield, and leg intermuscular fat. It was concluded that ration with 3.0 Mcal ME favored better results for Suffolklambs fed and finished in creep feeding.Key Words: cuts, muscularity, sheep, Suffolk

Desempenho, características de carcaça e resultado econômico de cordeiros criados em creep feeding com silagem de grãos úmidos de milho

Objetivou-se, com este trabalho, estudar niveis de substituicao (0; 50 e 100%) do milho grao seco moido pela silagem de graos umidos de milho na racao de cordeiros alimentados em creep feeding. Vinte e quatro cordeiros Suffolk foram avaliados quanto ao desempenho, pesos e rendimentos das carcacas. Tambem foi realizada uma analise economica. As racoes foram fornecidas ad libitum, sendo suas sobras pesadas para o calculo do consumo medio por animal. Ao atingirem 28 kg de peso vivo, os cordeiros foram submetidos a jejum por 16 horas e, entao, novamente pesados para se obter o peso vivo ao abate. Apos o abate, os animais foram eviscerados para se obterem os pesos e rendimentos de carcaca quente. As carcacas permaneceram por 24 horas em câmara de refrigeracao, sendo novamente pesadas para se obterem os rendimentos de carcaca fria e as perdas por resfriamento. Os resultados revelaram que nao houve efeito dos niveis de substituicao sobre ganho medio diario de peso vivo, idade ao abate, pesos e rendimentos das carcacas quentes e frias, indicando que a silagem de graos umidos de milho pode ser utilizada em substituicao ao milho moido na alimentacao de cordeiros. Como o peso ao abate foi pre-fixado, as variacoes nas idades ao abate fizeram com que essa variavel exercesse influencia sobre os desempenhos, pesos e rendimentos e, quanto maiores essas idades, piores os resultados dos parâmetros avaliados. O tratamento com 50% de silagem de graos umidos apresentou os melhores resultados economicos e o tratamento sem silagem de graos umidos foi o de menor rentabilidade.

Níveis de energia no desempenho e características da carcaça de cordeiros alimentados em creep feeding

RESUMO - O trabalho foi realizado no Setor de Ovinocultura da Universidade de Marilia, objetivando estudar os efeitos de tres niveis de energia (2,6; 2,8 e 3,0 Mcal EM/kg MS) na racao de cordeiros inteiros Suffolk criados em creep feeding, sobre o desempenho e caracteristicas de carcaca. Na paricao numerava-se e registravam-se o peso ao nascer dos cordeiros que, posteriormente, foram distribuidos aleatoriamente, compondo doze repeticoes por tratamento. As racoes foram isoproteicas (18,46% PB) fornecidas ad libitum duas vezes ao dia, pesandose as respectivas sobras. Os cordeiros foram pesados a cada 14 dias, permanecendo com as ovelhas ate atingirem o peso vivo final, preestabelecido em 31 kg. Em seguida, os cordeiros permaneceram em jejum alimentar por 16 horas, ate o momento do abate, obtendo-se o peso vivo ao abate. Apos o abate, registraram-se o s pesos da carcaca quente e do conteudo digestivo, para o calculo do peso de corpo vazio. As carcacas permanecerem por 24 horas na câmara de refrigeracao em temperatura de 5 o C, obtendo-se o peso da carcaca fria. Para o ganho medio diario ocorreu diferenca significativa entre os tratamentos, utilizando-se como covariavel a idade de abate, com melhor desempenho para os cordeiros que receberam a racao com 3,0 Mcal EM. Para as caracteristicas da carcaca nao houve efeito dos tratamentos. Concluiuse que o nivel 3,0 Mcal EM foi o mais indicado para a racao de cordeiros Suffolk alimentados e terminados em creep feeding.

Qualidade da carne de cordeiros criados em creep feeding com silagem de grãos úmidos de milho

The experiment was carried to study three three levels (0, 50 e 100%) of high moisture corn silage replacing dry corn grain in rations of lambs fed in creep feeding. Twenty four Suffolk lambs were evaluated to qualitative and quantitative loin (longissimus dorsi) characteristics. Lambs were weighed until to reach pre-fixed slaughter weight, 28 kg LW. Cold carcasses were cut in seven anatomical regions. Four measures were taken on longissimus dorsi surface: maximum width; minimal depth; minimal fat depth and maximum fat depth and loin eye area. Loins were dessecated to determine muscle, fat and bone proportions, chemical composition and shear force. Results showed that replacing levels did not affect shear force and loin measures, except for loin eye area, according to quadratic regression with higher values observed in rations with high moisture corn silage. Chemical composition analysis showed that replacing levels just influenced loin fat content, that increased linearly according to silage adding. There was no effect on muscle, bone and fat proportions, considering corn replacing levels. It was concluded that is possible replace dry corn by high moisture corn silage in creep feeding rations to finish lambs, keeping good quality meat.

Níveis de feno de alfafa e forma física da ração no desempenho de cordeiros em creep feeding

Lambs performance fed on creep feeding and fedlot were evaluated at two experiments. In the first experiment, thirty two 3/4 Suffolk lambs were fed on creep feeding, weaned at 56 days of age and, after, were confined. Lambs were fed four different treatments: 1. without supplemmentation; 2. supplemmentation with ground corn and soybean meal; 3. ground corn, soybean meal and 15% alfalfa hay; 4. ground corn, soybean meal and 30% alfalfa hay. After weaning, lambs that received concentrate supplemmentation were confined with the same diet until 30-32 kg live weight. In the second experiment, thirty two 3/4 Suffolk lambs were fed on creep feeding with pelleted and ground diets until to reach 26 or 28 kg live weight to be slaughtered. Diets were isoprotein (21% CP) and isoenergetic (2.9 Mcal ME/kg DM). Lambs supplemmented during suckling time presented higher live weight gain (plus 147.4 g/d) than non supplemmented ones. Alfalfa hay levels did not affect lambs performance. However, on the feedlot, the maximum efficiency expected for males weight gain, according to regression analysis, would be 18.7% of alfalfa hay added to ration. Better lambs performance was observed with pelleted diets compared to ground ones. Males fed pelleted diets reached 26 and 28 kg of slaughter weight at 55 and 60 days old, respectively.

Valor nutricional e características estruturais de gramíneas tropicais sob adubação nitrogenada

EnglishThe experiment was carried out in the expe- rimental farm of Unioeste, Marechal Candido Rondon, PR, Brasil, with the objective of evaluate the effects of increasing N doses under structural features and chemical composition of three tropi- cal forage grasses. The experimental design used was of randomized blocks in factorial scheme 3x4, with three tropical forages (Panicum maximum cvs. tanzânia and mombaca, and Brachiaria sp. cv. mulato) and four doses of N (0; 40; 80 and 160 kg/ha) taking urea as N sources. Were evaluated: canopy height leaf/stem ratio, diameter and height of pseudoculm, and contents of crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and mineral matter (MM). There was effect of N doses on canopy height and height of pseudoculm that showed quadratic behavior. The leaf/stem ratio responded negatively to N doses, while the diameter of pseudoculm was influenced only by forages. For CP content was found significance of interaction of factors, being that in dose of 80 kg/ha of N the Tanzania grass was higher than the other. The contents of NDF responded of form quadratic to N doses, while the contents of ADF were influenced only by forages. portuguesO experimento foi conduzido na Fazenda Ex- perimental da Unioeste, Marechal Cândido Rondon, PR, Brasil, com o objetivo de avaliar os efeitos de doses crescentes de N sobre caracteristicas estruturais e composicao quimica de tres gramineas forrageiras tropicais. O delineamento experimen- tal utilizado foi o em blocos casualizados em es- quema fatorial 3 x 4, com tres forrageiras tropicais (Panicum maximum cvs. tanzânia e mombaca, e Brachiaria sp. cv. mulato) e quatro doses de N (0; 40; 80 e 160 kg/ha) tendo como fonte a ureia. Foram avaliados: a altura do dossel, a relacao folha/colmo, a proporcao de folhas e de colmos na forragem produzida, o diâmetro e a altura do pseudocolmo, e os teores de proteina bruta (PB), fibra em detergente neutro (FDN), fibra em deter- gente acido (FDA) e materia mineral (MM). Houve efeito das doses de N sobre a altura do dossel e sobre a altura do pseudocolmo, que apresentaram comportamento quadratico. A relacao folha/colmo respondeu de forma negativa as doses de N, enquanto o diâmetro do pseudocolmo foi influen- ciado apenas pelas forrageiras. Para o teor de PB foi constatada significância da interacao dos fatores, de forma que na dose de 80 kg/ha de N o capim tanzânia foi superior aos demais. Os teores de FDN responderam de forma quadratica as doses de N, enquanto os teores de FDA foram influenciados apenas pelas forrageiras.

Características produtivas, estruturais e bromatológicas dos capins Tifton 85 e Piatã e do feijão-guandu cv. Super N, em cultivo singular ou em associação

This trial aimed at evaluating characteristics as: production, structural and nutritional requirements of Tifton 85 and Piata grasses and pigeonpea in single or intercropped tillage, with and without nitrogen application. The experimental plot in randomized blocks with plots subdivided through time, with 7 treatments in the main plots and three periods of evaluation on subplots with four replications. The studied treatments were: Cajanus cajan cv. Super N (pigeonpea), Brachiaria brizantha cv. single Piata without application of nitrogen (N); B. brizantha cv. Piata in association with pigeonpea; B. brizantha cv. single Piata with application of N (150kg ha-1); Cynodon sp. Tifton 85 in a single crop without application of N; Tifton 85 in association with pigeonpea and Tifton 85 plus an application of N (150kg ha-1) and three cycles of evaluations. The association of Tifton 85 and Piata grasses with pigeonpea provided forage production like nitrogen fertilizer and increase crude protein content and a reduction on neutral detergent fiber contents. Tifton grass was less tolerant to shading from pigeonpea.

Production of tifton 85 hay overseeded with white oats or ryegrass

The objective of this experiment was to estimate the curve of dehydration, chemical composition and in vitro dry matter digestibility (IVDMD) and crude protein digestibility (IVCPD) of tifton 85 hay, produced single or overseeded with ryegrass or white oat IPR 126. The experimental design was in randomized blocks, in a 3 × 10 factorial arrangement, with three cropping systems and ten evaluation times (0, 4, 8, 24, 28, 32, 48, 52 and 56 and 71 hours after harvest) during the dehydration process. For chemical composition and in vitro DM and CP digestibility, the experimental design was in randomized blocks with three cropping systems and three evaluation times (before cutting, before baling and 100 days after of storage). It was found that tifton 85 intercropped with white oat kept its higher nutritional value after storage, with 19.78% crude protein and 70.03% of in vitro dry matter digestibility. The participation of white oat in tifton 85 area was 57.04% and for ryegrass, it was 38.52%, but the dry matter yield of single tifton 85 was higher than other intercrops. Thus, it is recommended an oversowing of winter annual species on Tifton 85, without moisture restriction, because of the benefits obtained in the hay nutritional value.

Produção de forragem, características estruturais e eficiência de utilização do nitrogênio em forrageiras tropicais sob adubação nitrogenada

This study aimed to evaluate the effects of increasing doses of nitrogen on the morphogenesis, structural and productive grass Panicum maximum cvs. Mombaca and Tanzania, and Brachiaria sp. Mulato. The experiment was conducted under field conditions. The experimental design was randomized blocks in a 3x4 factorial design with three forages ( Panicum maximum cvs. Tanzania and Mombaca and Brachiaria sp. cv. Mulato), four N rates (0, 40, 80 and 160 kg ha-1) with three replications. Were evaluated the following parameters: fresh matter production (FMP), dry matter production (DMP), plant height, percentage of dry matter, leaves per tiller, dry matter accumulation rate (DMAR) and nitrogen use efficiency (NUE). Grasses Mombasa and Tanzania showed similar results, and both were superior to Mulato grass for the production of fresh and dry matter. The three species responded to nitrogen application, with an increase in FMP, DMP, DMAR, height and number of tillers. The maximum efficiency in use of N was obtained with a dose of 120 kg ha-1.