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Physiological and productive characteristics as affected by environmental treatments in broiler chicks.
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Abstract: EXPERIMENT : I
This experiment planned to study the importance of exposed the birds to high environmental temperature 38oC at early age. Otherways, adapt the birds on the high temperature to arrange their physiological set up to withstand expected sever changes in the environmental temperature. In this case, adapted birds live, growth and produce normally in unfavorable condition.
1 -Average live body weight and body weight gain of broiler chicks exposed to 38oc at the age of 42 days old were decreased significantly by heat exposure.
2 -Insignificant differences were found among groups stressed early or early and later (acclemation) comparing to birds reared under normal temperature.
3 -Exposed broiler chicks to heat stress, whichever, at early in life and acclemated (early and late) improved the body weight and weight gain at 49 days of age and due to overall.
4 -Exposed broiler chicks ot heat stress, Whichever, early or later in life decreased the feed intake significantly.
5 -The exposure of heat stress, early and later (acclimation) in life increased the feed intake significantly during the exposure of stress or consecutive 2 weeks which had been affected by heat stress.
6 -The exposed to heat stress early, later in life or acclimated birds (exposed early and later in life to heat stress) had significant improvement on the feed needed to produce unit of body weight gain. Whereas, the best improvement was obtained with the acclemated birds.
7 -Heat stress caused markedly increase in mortality rate, whichever, early heat stress or later in life.
8 -Early and later heat stress (acclimation) reduced the mortality rate about 4 % counterpart 16 % with the later stress group .
9 -Heat stress caused significantly increased blood pH, but caused significant decreased on total protein.
10-The acclamation of heat stress at early in life did not effect on blood pH which elevated as result of heat stress.
11-Neither early heat exposure nor acclimated did (early and later) have a significant effect on total protein as will as albumin and globulin comparing with unstressed control group.
12-The acclimation of heat stress at early in life attenuate or efface the negative effect of heat stress on total protein as will as albumin and globulin which depressed it when exposed again later in life.
13-Exposing to heat stress early in life at 5-7 days of age resulted insignificantly in triaiodothryonine hormone (T3) when birds exposed to heat stress later in life at (36 - 38 days).
14-Triiodothyronine hormone (T3) affected significantly (P<0.01) corresponding to heat stress on control group at 36 and 37 days only, but, at 38 days did not affected. This may be due to the acclimation to the heat stress resulted from exposed the birds to the previous two days before.
15-Heat Stressed later birds had signifecantly (P<0.05) lower hematocrite values and hemoglobin concentration after heat stress treatment as compared with those values before through all ages.
16-Birds acclimated to heat stress reflected a slight and nonsignificant reduction in their hematocrite values and hemoglobin concentration.
EXPERIMENT : II
An experiment designed to elucidate the importance and the role of diazepam and compare its levels as tranquilizer on the broiler chicks performance under heat stress and normal condition.
1 -The addition of diazepam had significant (P<0.05) more on body weight and weight gain of chicks with or without heat stress than control.
2 -The addition of diazepam, whichever, at level of 1 or 0.5 ppm ameliorated the dramatic or negative effect of heat stress on body weight.
3 -There were significant differences (P<0.05) between groups fed 0.5 or 1 ppm diazepam with or without heat stress which gained more over rather than control group.
4 -The addition of diazepam, Whichever, at level of 1 or 0.5 ppm increased the feed intake with or without heat stress at 49 days of age which had been affected by heat stress at 42 days of age.
5 -The addition of diazepam at levels of 1 or 0.5 ppm had significant decrease on at the feed needed to produce unit of body weight gain with or without heat stress. Whereas, the best improvement was obtained with the highest levels.
6 -The level of 0.5 or 1 ppm diazepam reduced the mortality rate about 50% as compared with the control group during the period of 1 to 35 or period 42 - 49 days of age.
7 -Mortality rate under heat stress were markedly increase about 20 % at 35 - 49 days of age.
8 -During the heat stress period, the mortality percentage was 16 %, 4 % or 2 % on the groups of the control, 0.5 ppm or 1 ppm diazepam, respectively.
6 -The addition of diazepam at level of 1 or 0.5 ppm ameliorated the elevation of pH, which affected by heat stress.
7 -Birds fed diazepam with or without heat stress tended to increase the total plasma proteins as will as "albumin" and "globulin over those obtained from control birds.
9 -Triiodothyronine hormone (T3) not affect significantly differences by diazepam without or with heat stress, but, all treated with diazepam groups were slightly inferior corresponding to heat stress but not significantly.
EXPERIMENT: III
An experiment designed to elucidate the importance and the role of avizyme and compare its levels on the performance of the broiler chicks and some physiological characters.
1 -Live body weight and weight gain of chicks had significant (P<0.05) more by avizyme treatments rathar than control.
2 -Additional of avizyme to diet for broiler exposed to heat stress showed effacement to dramatic loss or negative effect of heat stress on body weight.
3 -The addition of avizyme, Whichever, at level of 2 or 0.5 g/kg feed improved the feed intake with or without heat stress at 49 days of age which had been affected by heat stress at 42days of age.
4 -The addition of avizyme at levels of 2 or 0.5 g/kg feed had significant decrease on at the feed needed to produce unit of body weight gain with or without heat stress. Whereas, the best improvement was obtained with the highest levels.
5 -Mortality percentage under heat stress were markedly increase.
6 -During the heat stress period, the mortality percentage was 16 %, 4 % or 4 % on the groups of the control, 0.5 or 2 g/kg feed avizyme, respectively.
7 -The addition of avizym, whichever, at level of 2 or 0.5 g/kg feed did not effect on blood pH which elevated as result of heat stress
8 -Birds fed avizyme with or without heat stress tended to slightly increase the total plasma proteins as will as "albumin" and "globulin over those obtained from control birds.
9 -Results carried out that, with or without, before or after heat stress, triiodothryonine hormone (T3) did not affected significantly by avizyme.
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| Publication year |
2000
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| Availability location |
مكتبة معهد بحوث الانتاج الحيوانى- شارع نادى الصيد -الدقى - الجيزة
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| Availability number |
693
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| Organization Name |
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| Country |
Egypt
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| Department |
Poultry Breeding Research Department
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| Author(s) from ARC |
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| Agris Categories |
Animal physiology - Nutrition
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AGROVOC
TERMS |
Broiler chickens.
Environmental factors.
Heat stress.
Neuroleptics.
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| Publication Type |
PhD Thesis
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