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Document Type |
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Article In Journal |
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Document Title |
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Effect of Water Spray Cooling Followed by Forced Ventilation on Some Physiological Characteristics and Milk Production in Pregnant Friesian Cows Under Arid Environment تأثير التبريد برش الماء المتبوع بالتهوية على بعض الصفات الفسيوليوجية وإنتاج الحليب للأبقار الفريزيان الحامل تحت ظروف بيئة المناطق الجافة. |
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Document Language |
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Arabic |
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Abstract |
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ABSTRACT. Thirty lactating purebred Friesian cows of 430-480
kg. body weight normal and free from diseases were used in this
study. The cows were paired into two similar groups according to
their age, parity, body weight, and preview yield.
1. The first group was kept between 1000 and 1600 hr. under
cooling system. Cows was sprinkled for 30 seconds, followed by
forced ventilation for 4.5 minutes. The cooling cycles were repeated
every half an hour.
2. The second group was kept under normal conditions as a control
group.
The cows were provided their daily feeding allowances two
times a day in two equal amounts of rations to cover the animal requirements.
Drinking water was available continuously. The ambient
temperature and relative humidity were recorded through the
experimental period.
Physiological responses:
Overall means of respiration rate, pulse rate and rectal temperature
were (56.11 – 0.24 vs 59.50 ?– 0.28 breaths/min) ; (62.75
– 0.22 vs 70.59 – 0.25 breaths/min) and (38.18 – 0.02 vs 39.25 –
0.02¡C) in the cooling and control groups, respectively. Difference
between the two groups average was statistically significant
(P†0.01).
Hematological parameters:
Averages of RBCs were (7.50 – 0.11 x 1012/L. vs 6.91 – 0.12 x
1012/L.) in the cooling and control groups, respectively. Difference
between the two groups was statistically significant (P†0.01).
While, averages of WBCs were (7.39 – 0.15 x 109/L. vs 7.05 –
0.17 x 109/L.) for the cooling and control groups, respectively.
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Difference between the two experimental groups lacked statistical
significance.
Total milk yield during different pregnant intervals in the cooling
group was higher than that of the control group (1951 Kg vs
1095 Kg in the two groups, respectively).
From another point, the results indicated that, total milk yield in
the cooling group during the first five months of pregnancy interval
was (1297 kg vs 796 kg), the difference was 501 kg in the side
of cooling group. This difference = 62% during the same period.
Also, the results showed that total milk yield in the cooling
group was higher than that of the control group during the second
period of pregnancy interval (3 months) (542 kg vs 236 kg in the
two groups, respectively). The difference between the two groups
was 306 kg = 129% of control group. Moreover during the third
period of pregnancy (one month) total milk was (121 kg vs 63 kg)
in the two groups respectively. The difference between the two
groups equals 58 kg = 77% increase than the value of control
group.
It was concluded from this study that the adopted cooling system
had efficiently ameliorated the depressive effects of summer
heat stress prevailing in Saudi Arabia on the performance of Friesian
cattle. It seems that water sprinkling followed by a forced
ventilation technique is a simple safe and practical method for decreasing
the heat stress effects in dairy cows and consequently improves
productivity and reproductivity of cows in hot climates. |
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ISSN |
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1319-1039 |
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Journal Name |
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Meteorology, Environment and Arid Land Agriculture Sciences Journal |
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Volume |
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15 |
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Issue Number |
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1 |
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Publishing Year |
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1424 AH
2004 AD |
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Article Type |
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Article |
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Added Date |
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Thursday, May 17, 2012 |
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Researchers
| سمير عطية نقادي | NAGADI, S A | Investigator | Doctorate | samir@kau.edu.sa |
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