| Titles |
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English :
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Thermo-respiratory responses, hematological and hormonal reactions of buffalo and friesian calves to the rise in environmental temperature
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Arabic :
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استجابة حرارة الجسم و التنفس و خصائص الدم و الهرمونات في عجول الجاموس و الفريزيان لارتفاع درجة حرارة البيئة
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| Abstract |
Five Egyptian buffalo calves (BC) and four Friesian calves (FC) were used to study the thermo-respiratory responses, hematological and hormonal reactions to diurnal, seasonal, and steady heat stress (HS,40°C) conditions. The study was carried out on the same animals at two stages of age, 9 and 18 momhs. The study comprised two cxperiments, the first one was carried out under natural environmental conditions (NC) during three months in winter and summer at each age. The second experiment was conducted under HS conditions continuously for 15 successive days every season for each age. The BC showed slight daily fluctuation in rectal temp. (RT) within the day, There was clear accordance between hair (HT), skin (ST) and air temp. (AT) during seasons and at diurnal times. Under HS. values of HT. ST and RT increased in both species and ages by 0.4-4.0 °C. The respiration rate increased under heat stress to near two times the rate at wimer morning for buffaloes. and five times for Friesian at 9 mo. of age. while the rate increased nearly three times at 18 mo. in both species. The BC had higher hematocrit values than FC under all the thermal conditions and ages. The values of hemoglobin were lower in winter than in summer in both species and ages. There were clear species differences in all values of red and white blood cells in the two seasons and HS conditions. The FC had higher values of the monocytes. esinophils, and the ratio neutrophils/lymphocytes than BC. under HS. At any age, BC had greater concentration of T3 and lower concentration of T4 than FC under the NC. Heat stress induced reduction in T3 in both species with more response of BC, down to 60% of that at hot summer. The correlation coefficients between the studied traits were determined . It is clear from this study that the effects of specie. age and environmental air temperature were significant on thermo-respiratory responses with sporadic effects on hematological and hormonal traits.
Keywords: Buffalo, caltte, heat stress, season, blood, hormones.
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| Publication year |
2004
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| Pages |
353-366
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| Availability location |
معهد بحوث الانتاج الحيوانى- شار ع نادى الصيد- الدقى -الجيزة
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| Availability number |
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| Organization Name |
Animal Production Research Institute (APRI)
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| serial title |
Egyptian Journal Animal Production
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| Author(s) from ARC |
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| External authors (outside ARC) |
محمد محمود الشافعى
جامعة القاهرة
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| Agris Categories |
Animal physiology - Nutrition
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AGROVOC
TERMS |
Blood.
Blood disorders.
Calves.
Cattle.
Environmental temperature.
Heat stress.
Hormones.
Seasons.
Water buffaloes.
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| Publication Type |
Journal
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