STUDIES ON THE HAIRCOAT OF HOLESTEINI. FRIESIAN CALVES IN RELATION TO THEIR FUTURE PERFORMANCE | ||||
Journal of Animal and Poultry Production | ||||
Article 5, Volume 28, Issue 10, October 2003, Page 7183-7196 PDF (3.77 MB) | ||||
Document Type: Original Article | ||||
DOI: 10.21608/jappmu.2003.245285 | ||||
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Authors | ||||
R. A. Guirgis,1; S. H. EI-Khashab2; R. E. Khidr1; A. Soliman3 | ||||
1Desert Research Centre, Mataria, Cairo, Egypt | ||||
2Faculty of Agriculture, Menoufyia University, Shebin EI-Kom, Egypt | ||||
3Faculty of Agriculture, Zagazig University, Zagazig, Egypt | ||||
Abstract | ||||
This experiment was carried out using 397 newly born Friesian Holstein calves to study some of hair coat characteristics during the different seasons up to one year of age and their relations to some physiological parameters and animal body weight. Hair coat measurements involved field observations (coat depth, density, curliness and luster) and laboratory measurements (fiber density, fi er length, fiber crimping and fiber shedding). Physiological parameters dealt with rectal temperature, skin and hair temperature and respiration rate. In the present study, hair coat characteristics of calves showed strong seasonal variations. Coat type was short, more medullated, less del se and h ad a very few number of crimps in summer, whereas in winter it was dense, long and low in percentage of medullated fibers. Physiological parameters showed higher values in summer tha~ those in winter season. Temperature gradients of rectal temperature and each of sk n temperature, mid point coat temperature and surface coat temperature showed a higher value fer insulation during winter season than those of summer. Daily weight gain showed high positive correlation (P<0.01) with fiber density (0.611), fine undercoat length (0.603), coarse undercoat percentage (0.719), coat depth (0.838), curliness (0.734) and belly cover depth (0.775). It could be concluded that the seasonal fluctuations in hair coat characteristics might be regarded as one means of animal adaptability to the environmental factors which surrounded the animals. Such fluctuations had also strong correlations with the physiological responses of animal body as well as with daily weight gain. | ||||
Keywords | ||||
Friesian calves; hair coat characteristics; physiological parameters; body weight | ||||
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