Alda Lúcia Gomes Monteiro

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

Características do processo de ingestão de forragem por novilhas holandesas em pastagens de capim-mombaça

Para avaliacao da influencia da estrutura do dossel de pastagens tropicais sobre o processo de ingestao de forragem por bovinos, cinco alturas de dossel (60, 80, 100, 120 e 140 cm) de uma pastagem de capim-mombaca (Panicum maximum, Jacq.) foram estabelecidas, em um delineamento inteiramente casualizado, com duas repeticoes. Quatro novilhas da raca Holandes Preto e Branco com coletores de fezes e urina foram utilizadas em testes de pastejo de 45 minutos. O numero de bocados e o tempo de alimentacao foram registrados com o uso de contadores e cronometros. A massa de forragem total consumida foi obtida pela tecnica de dupla pesagem. Com o aumento na altura do dossel, observou-se aumento linear na massa de bocado. O aumento do comprimento das lâminas foliares expandidas e em expansao resultou em consumo quase que individual de folhas, refletindo em aumento linear no tempo por bocado e em reducao linear na taxa de bocados. Uma vez que o aumento no tempo por bocado foi proporcionalmente maior que o aumento da massa de bocado, a massa de forragem total consumida e a taxa de ingestao estabilizaram-se nas maiores alturas da pastagem. As limitacoes fisicas impostas pela estrutura do dossel levaram a menor eficiencia de captura de forragem pelos animais nas maiores alturas do dossel. O consumo de forragem foi maximizado a altura de 109,3 cm.

Produção de ovinos de corte em quatro sistemas de produção

The potential performance of lambs and ewes from the Suffolk breed in pasture of Tifton grass 85 (Cynodon spp.) and ryegrass (Lolium multiflorum) was evaluated in different production systems: lambs weaned with 60 days and kept in pasture; lambs with ewes and kept in pasture; lambs with ewes and kept in pasture with creep feeding; feedlot confined lambs with alfalfa hay + balanced ration. The treatments were applied when the lambs reached 60 days of age until slaughter time, at 32 kg, and were allocated in a completely randomized experimental design, with three replications. A continuous grazing system, with variable stocking rate, was used in pasture treatments. Important effect of the treatments on performance of the lambs was observed. Feedlot confined lambs showed higher daily weight and at lower age at slaughter time. Creep feeding supplementation at 1% LW, did not have effect in lambs with more than 60 days of age kept with the ewes in Tifton 85 grass pasture. The presence of the ewe in the pasture showed important and positive effect in the individual performance of lambs as compared to lambs weaned at 60 days of age.

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.

Rentabilidade da produção de ovinos de corte em pastagem e em confinamento

Os objetivos neste trabalho foram analisar a viabilidade economica de sistemas de producao de cordeiros e identificar os componentes de maior influencia no custo de producao. O estudo foi realizado em duas etapas. Na etapa 1, realizou-se a comparacao de quatro sistemas de terminacao de cordeiros: 1) desmame aos 60 dias e terminacao em pasto; 2) cordeiro com mae em pasto; 3) cordeiro com mae em pasto e concentrado (1% PC/dia) em creep feeding; e 4) desmame aos 60 dias e confinamento. Na etapa 2, um modulo de 150 ovelhas em 9 ha de pasto cultivado nos sistemas em pastagem e 7 ha no confinamento foi proposto a partir do experimento para avaliacoes economicas, considerando a venda de cordeiro vivo terminado ou abate e venda de carne, alem da venda de matrizes. Foram realizados calculos de custo fixo (depreciacao), variavel (materiais, mao-de-obra, transporte, abate, juros, conservacao, despesas gerais) e total (fixo+variavel), lucratividade e rentabilidade, valor presente liquido, taxa interna de retorno e custo/beneficio. O maior custo total foi observado no confinamento e o menor, no sistema de cordeiro terminado com a mae em pasto. A margem liquida na venda de cordeiros foi negativa em todos os sistemas. A venda de carne apresentou margem liquida negativa apenas para terminacao em confinamento. A taxa interna de retorno para venda de carne foi: 1,4% no desmamado em pasto; 4,3% no de cordeiro com mae em pasto; 2,1% no creep feeding; e -2,3% no confinamento. Os componentes do custo operacional total com maior influencia sobre o custo de producao nos sistemas a pasto, em ordem decrescente, foram mao-de-obra e alimentacao; no confinamento, foram alimentacao e mao-de-obra. A venda da carne apresentou lucratividade maior que a venda de cordeiro vivo, com maior valor no sistema sem desmame terminado na pastagem.

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.

Sensitivity and specificity of the FAMACHA © system in Suffolk sheep and crossbred Boer goats

Sheep and goats are the species of farm animal with the highest growth rate in Paraná State. The main problems facing Paraná State flocks are gastrointestinal parasites and anthelmintic resistance. One of the newest resources used to slow down the development of anthelmintic resistance is the FAMACHA(©) system, a selective method useful for controlling gastrointestinal verminosis in small ruminants. The purpose of the present research was to evaluate the sensitivity and specificity of the FAMACHA(©) system in sheep and goats and to compare the results for both species. The conjunctivae of 83 Suffolk ewes and 60 adult crossbred Boer does were evaluated by the same trained person using the FAMACHA(©) system. The packed cell value (PCV) served as the gold standard for clinical FAMACHA(©) evaluation. To calculate the sensitivity and specificity of the FAMACHA(©) system, different criteria were adopted in turn: animals classified as FAMACHA(©) (F(©)) 4 and 5, or 3, 4 and 5, were considered to be anemic (positive test), and animals classified as F(©)1, 2 and 3, or 1 and 2 were considered to be non-anemic (negative test). Three standard values of PCV, namely ≤19%, ≤18% or ≤15%, were used to confirm anemia. At all cut-off levels, the sensitivity increased if F(©)3 animals were included as being anemic. However, changes in levels of sensitivity were associated with reciprocal changes in specificity. The sensitivity was higher for sheep than for goats, excepting when the criteria included PCV≤18 and F(©)3, F(©)4 and F(©)5 were considered positive. In contrast, the specificity was always lower in sheep for any criteria adopted. Other than in goats, using the ≤15 cut-off level for sheep, it is possible to opt not to drench the animals that were shown to be F(©)3 because the sensitivity is still high, indicating that few animals that should have been drenched were overlooked. In goats, in contrast, the low sensitivity at all cut-off levels made it too risky to leave F(©)3 animals undrenched. Even though the number of correct treatments for goats was always higher than that for sheep, the opposite was true for the kappa index for all the criteria tested. Therefore, the FAMACHA(©) system is suitable for the identification of anemic animals of both species. It is necessary that all small ruminants classified as FAMACHA(©) level 3 are also treated to increase the sensitivity of the method.

Padrões de deslocamento e procura por forragem de novilhas leiteiras em pastagem de capim-mombaça

To evaluate grazing strategies of cattle on pastures, four Holstein black and white coating heifers were submitted to five sward heights of mombacagrass (Panicum maximum Jacq.) pasture, in a completely randomized design, with two replications, between February and April, 2002. The experimental animals were evaluated during 45 minutes tests. Number of bites, number of feeding stations, number of steps and feeding time were measured, using chronometers and counters. The number of feeding stations per minute decreased quadratically (Y= 16.3199 - 0.2424 x + 0.000996 x2, R2 = 0.9328, P = 0.0031), from low to tall sward, as a result of the greater available mass present in the highest sward heights, that reduced the searching for other feeding stations. The number of steps between feeding stations increased (Y= 0.7247 + 0.01603 x, R2 = 0.6172, P = 0.0043) increasing the exploration of pasture environment. With the increase in available forage dry matter, the animals reduced total number of steps (Y= 513.998287 - 2.659875 x, R2 = 0.728076, P = 0.0016), steps by minute (Y= 11.567445 - 0.058396 x, R2 = 0.724633, P = 0.0013) and, consequently, the intensity of area utilization (Y= 9.533139 - 0.051351 x, R2 = 0.7708, P = 0.0005), as the greater sward height assured high forage intake. The animals showed adaptive feeding strategies to different pasture structures, in an attempt to improve their ingestive efficiency.