Frederico Fontoura Leinz

Características de carcaça de cordeiros Suffolk abatidos em diferentes idades

The effect of slaughter age on non-carcass components and carcass characteristics was evaluated in 35 Suffolk lambs slaughtered at average age of 90, 130 or 170 days, fed corn silage and concentrate (19.6% CP). As the slaughter age increased, animal live weight and carcass weight linearly increased, and some non-carcass components as blood, head, legs and full viscera percentage linearly decreased, leading to a linear increase in carcass yield. As the slaughter age increase, it was observed change in the proportion of carcass components with a linear increase of fat percentage, a linear decrease in bones percentage and no change in the muscle percentage. A linear decrease in the hindquarter, a linear increase in the ribs and no change in the forequarter carcass cuts was observed with increasing slaughter age. Higher slaughter age led to a linear increase in carcass measures and compactness. The slaughter age of Suffolk lambs, to produce suitable carcasses for retail, is between 110 and 130 days of age.

Utilização de carneiros de raças de corte para obtenção de cordeiros precoces para abate em plantéis produtores de lã

RESUMO - Sessenta e nove cordeiros filhos de ovelhas das racas Ideal ou Corriedale cobertas com machos das racas Suffolk, Ile de France, ou da mesma raca materna, foram usados para avaliar o seu desempenho e as caracteristicas de carcaca. Os animais permaneceram em pastagem ate o desmame (60 dias), foram confinados por 90 dias e alimentados com racao a base de silagem de milho e concentrado. Foi usado delineamento completamente casualizado em esquema fatorial. O uso de machos de corte sobre femeas lanigeras nao causou efeito sobre o peso ao nascer e ao desmame das crias, porem aumentou o peso e a compacidade das carcacas, sem alterar as proporcoes de traseiro e costilhar. A espessura de gordura subcutânea nao foi influenciada pelo genotipo, apresentando-se maior para femeas. A area de olho de lombo nao apresentou diferenca entre genotipos. As medidas de carcaca mostraram diferenca entre genotipos, sendo as do cruzamento com Suffolk mais compridas, seguidas pelos mesticos de Ile de France.

Parâmetros bromatológicos e fermentativos das silagens de milho e girassol

At the Instituto de Zootecnia, APTA, Sao Paulo StateBrazil, it was carried out an experiment to evaluated the chemical quality and ruminal degradation for dry matter (DM), neutral detergent fiber (NDF) and protein (CP) of sunflower and corn silages. For chemical evaluation of the silages, a total randomized design with nine replicates was used. For in situ degradability was used a split-plot design with three replicates, in which the plots were the times of incubation and the subplot the silage. Sunflower silage showed higher concentration of crude protein (11.6 vs 9.4%), ether extract (10.1 vs 3.2%), acid detergent fiber (42.7 vs 31.9%) and lignin (9.4 vs 3.7%), and lower concentration of dry matter than corn silage (22.0 vs 34.6%), respectively; and also higher concentration of ammonia nitrogen (10.7 vs 5.8 %) and acetic acid (3.0 vs 0.79%) and lower concentration of lactic acid (3.7 vs 11.3%) than corn silage. The effective degradation rates of DM, NDF and CP were lower in the sunflower silage. Corn silage showed more favorable characteristics for ensiling process.

Avaliação de dois métodos de diagnóstico precoce de gestação em ovelhas: ultra-sonografia transretal e detector de prenhez para pequenos ruminantes (DPPR-80®)

No periodo de marco a maio de 2001, foram realizados os exames ultra-sonograficos em 88 ovelhas do Nucleo de Pesquisas Zootecnicas Sudoeste - Instituto de Zootecnia. Os animais foram examinados entre o 19o e 33o dia de gestacao pela ultra-sonografia transretal com exames executados em dias alternados, e do 25o ao 45o dia pelo detector de prenhez para pequenos ruminantes (DPPR-80O). O diagnostico foi considerado positivo pela ultra-sonografia transretal por meio da visualizacao do saco gestacional e embriao. Apos o 25o dia de gestacao foi observado tambem o batimento cardiaco embrionario, cuja frequencia e de 160 a 200 batimentos por minuto. Esta observacao foi dada como diagnostico de gestacao. Os nascimentos confirmaram os resultados dos exames. Dentre 88 femeas acasaladas, 3 abortaram durante o experimento e foram retiradas do grupo. Das 85 femeas restantes, 64 pariram. O diagnostico de prenhez por meio da ultra-sonografia transretal apresentou 35,29% de acuracia no 19o dia de gestacao, culminando em 82,35.00% no 31o dia de gestacao. Pelo detector de prenhez, a acuracia foi de 24,71% no 25o dia de gestacao e 34,12.00% no 45o dia. Foi possivel visualizar os batimentos cardiacos do embriao pela ultra-sonografia transretal a partir do 21o dia de gestacao e os primeiros placentomas foram observados ao redor do 25o dia de gestacao. A ultra-sonografia transretal mostrou-se um metodo superior ao detector de prenhez para pequenos ruminantes, para diagnostico precoce de gestacao em ovelhas.

Desempenho de cordeiros alimentados com silagem de girassol ou de milho com proporções crescentes de ração concentrada

Two experiments were conduct to evaluate the effect of dietary nutritive value and performance of sheep fed corn- or sunflower silage-based diet with increasing concentrate proportion (20, 40 and 60%). A factorial design (2x3) was used to evaluate nutritive value and digestibility coefficient of two silages with three concentrate levels and three sheep for each treatment. For lamb performance, a randomized block design in a factorial arrangement (2x3) was used to evaluate lamb performance, with five Suffolk lambs/treatment. Apparent digestibility coefficients of DM, OM, CF, NFE, NDF, ADF and cellulose were smaller for sunflower than for corn silage. Corn silage-based diets showed higher values of daily dry matter intake (709.5 x 609.7 g), daily live weight gains (181.8 x 108.2 g) and lower values of feed:gain ratio (3.82 x 5.53 kg DM/kg LW gain) than sunflower silage-based diets. Sunflower silage-based diets showed lower nutritive values than corn silage-based and smaller lamb performance. Lambs fed sunflower silage-based diets need more concentrate ration to obtain performance similar to those fed corn silage-based diets.

Inseminação artificial em cabras com sêmen congelado: resultados preliminares

Aiming to evaluate frozen goat semen in TRIS diluent with low egg yolk addition, progressive motility was evaluated soon after freezing and again 4 years later, resulting in 38.2 ± 7.4% and 31.4 ± 13.5%, respectively. Sixteen goats were oestrus synchronized through progesterone impregnated intravaginal sponges followed by PMSG injection on day 9. Vaginal sponges were withdrawn on day 11, with goats being artificially inseminated 46 hours later with semen frozen in straws and stocked during 4 years in liquid nitrogen. The nonreturn rate attained 31.2%. TRIS diluent with low egg yolk addition was considered as efficient in relation to frozen sperm evaluated both in vitro through progressive motility as in vivo through artificial insemination.