Duration Of Fattening Research Articles

The effect of the rearing system and biological factors on carcass conformation and slaughter traits of fattening chickens

The effect of the rearing system (intensive and semi intensive) and biological factors (genotype, age, sex) on absolute and index values of carcass conformation measures in chickens (metatarsus length, keel length, breast depth, thigh girth and breast angle) was investigated. In the trial Arbor Acres and Redbro chickens were used and duration of fattening was 42 and 50 days. Chickens at the age of 50 days had better conformation compared to chickens at the age of 42 days. Carcasses of male chickens had better conformation than female chickens. Genotype Arbor Acres had considerably higher values of relative conformation measures than chickens of Redbro genotype. Chickens reared in chicken coop had higher values for length of metatarsus, breast depth and thigh girth compared to chicken reared on free range. .

Effect of housing density, duration of fattening and initial body mass of one day old chickens on production of broiler meat of Cobb hybrid

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Quantitative methods to determine factors affecting profits of lamb fattening enterprises

The purpose of this study was to demonstrate the use of profit function regression model as a possible practical decision support tool in the lamb meat production. It was found that all independents variables except “Fattening Duration”, “Capacity Use”, “Total Other Expenditures” and “Number of Lambs”, had strong statistical associations (P < 0.01) with the profit from per kg live-weight. Because marginal impact of each independent vari­able on the profit was the estimated co-efficient value, they could simply be used to evaluate “what-if scenarios” and the risk of investment under changing circumstances in lamb meat production. It is, therefore, intended that lamb meat producers could use such modelling approach as a practical decision support tool.

Changes in the metabolic and contractile characteristics of muscle in male cattle between 10 and 16 months of age.

Samples of semitendinosus muscle from 28 male cattle (18 Salers and 10 Limousins) were taken at 10 months (biopsy) and at 16 months of age (at slaughter). The animals had received the same diet and were slaughtered after the same duration of fattening. The activities of isocitrate dehydrogenase and lactate dehydrogenase were measured in the muscle samples. The five lactate dehydrogenase isoenzymes were separated by electrophoresis under non-denaturing conditions and assayed by densitometry. Fibres were identified by histochemistry by myofibrillar ATPase and succinate dehydrogenase activities as SO (slow oxidative), FOG (fast oxidative glycolytic) or FG (fast glycolytic), and by immunohistochemistry by their reaction to monoclonal antibodies specific to slow and fast myosin heavy chain reactions in I, IIC, IIA, IIAB and IIB type fibres. The isocitrate dehydrogenase activity was not modified between 10 and 16 months of age; the lactate dehydrogenase activity decreased and was correlated with an increase in the proportion of the H isozyme to the detriment of the proportion of the M form. This period was characterized by an increase in fibre size, increased expression of MHC IIa, resulting in more IIA fibres, less IIB fibres, and an increase in the percentage of type IIAB fibres, however the proportions of SO, FOG and FG, when analysed statistically, were not modified between 10 and 16 months of age.