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1.
J Dairy Sci ; 90(12): 5643-50, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18024756

RESUMO

In an Alpine environment, diets based on local forage resources are needed to maintain the link with the territory and confer special characteristics to typical cheeses. Harvesting at a late stage of maturity, high mechanical losses, and frequent rainfall often make the hay that is harvested of a poor quality. The aim of this study was to evaluate the effects of 2 different conservation methods (late hay, LH, vs. early haylage, ES) of natural permanent meadows on milk production in dairy cows, on the chemical and microbiological characteristics of the milk, and on the quality of the cheese over the winter period. Haylage and hay were harvested from the same permanent meadow at the Vittorino Vezzani experimental farm in Sauze d'Oulx (45 degrees 02'N, 6 degrees 53'E, Italy). The ES forage was cut 4 wk earlier than traditional hay, wilted for 30 h, baled at a dry matter (DM) content of about 50%, wrapped with 6 layers of stretch film, and stored in a protected area. The LH forage was harvested later, when the weather conditions were favorable and, after a 3-d wilting, it was baled and stored indoors. After an 8-mo storage period, the ES had a greater crude protein concentration, organic matter digestibility, and net energy for lactation than LH and a lower neutral detergent fiber and acid detergent fiber. Forty multiparous lactating Aosta Red Pied cows were used in a 19-d period crossover design to assess the nutritional value of the stored forages. The diets included ES fed ad libitum and 3.5 kg of DM per cow of concentrate or LH fed ad libitum and 5.1 kg of DM per cow of concentrate. The dietary DM was 90.1% for the LH and 59.9% for the ES. The diets contained 12.6 and 13.0% crude protein and 48.6 and 48.0% neutral detergent fiber, for the LH and ES, respectively. The forage intake was greater in the ES treatment than in the LH treatment. The ES treatment produced more milk (1.7 kg/d) and more 3.5% fat-corrected milk (1.5 kg/d) than the cows on the LH treatment. The milk fat and protein concentrations were similar in both diets, resulting in a greater protein yield in the ES treatment. The lactose, pH, total bacterial count, and somatic cell count were not different for the treatments. The clostridial spores did not differ between the treatments from preharvest forage to cheese, and no differences were found in terms of cheese quality after maturation. Conserving forage as wrapped bale silage combined with an earlier harvesting date than traditional hay resulted in a suitable method to improve forage quality without increasing the risk of clostridial contamination in the milk and cheeses.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Queijo/normas , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Leite/normas , Altitude , Ração Animal/normas , Fenômenos Fisiológicos da Nutrição Animal , Animais , Queijo/microbiologia , Clostridium/crescimento & desenvolvimento , Fibras na Dieta/análise , Proteínas Alimentares/análise , Feminino , Itália , Lipídeos/análise , Leite/química , Leite/citologia , Leite/microbiologia , Proteínas do Leite/análise , Valor Nutritivo , Estações do Ano , Esporos Bacterianos , Fatores de Tempo
2.
Meat Sci ; 71(4): 713-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22061217

RESUMO

The effects of specific diets for commercial hybrids were investigated on 6 Casertana and 11 Mora Romagnola, two endangered Italian pig breeds. Average daily gain (ADG), feed conversion index (FCI), dressing percentage and meat and fat quality of animals bred under similar environmental and nutritional conditions were compared to define their optimal slaughtering weight. Animals were fed the same diets assuming that requirements of Mora Romagnola and Casertana did not differ, and changed every 30kg of weight gain. ADG and FCI were calculated every 15 days. Weight gains, divided into 5 groups based on live weight (LW) of animals (⩽60kg, 60160kg), showed higher values for Casertana than Mora Romagnola, particularly from 121 to 160kg LW (687g/d). Average FCI from 50 to 160kg LW was similar in both breeds (4.2). After 403 days of trial, animals were slaughtered at about 195kg LW. Carcass measurements showed that Casertana had higher dressing percentage and lean cuts than Mora Romagnola. Both breeds showed extraordinary high ultimate pH values of M. longissimus thoracis (5.96 and 6.15 for Casertana and Mora Romagnola, respectively) M. semimembranosus (6.37 and 6.30), showing an incomplete post mortem glycolysis. Colour of M. longissimus thoracis did not differ between breeds and was particularly dark. Chemical analysis of Casertana meat showed lower percentage of water and fat; the total amount of fatty acids (SFA, MUFA and PUFA) and the SFA/UFA ratio did not show significant differences between breeds. Results showed that from a growth point of view the optimal slaughtering weight of Casertana and Mora Romagnola should not exceed 160kg LW. Both breeds had an uncommon reactivity to stress probably due to interactions of genetic, nutritional and management factors.

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