| Titles |
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English :
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Effect of different energy and protien level on growth and reproduction in rabbits.
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Arabic :
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تأثير المستويات المختلفة من الطاقة و البروتين على النمو و التناسل في الارانب.
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| Abstract |
The present work aimed to study the effect of different energy and protein levels, i.e. different calorie: protein ratios on growth and reproductive perfomance of New Zealand white rabbits. The experimental work was carried out at EI-Kanater Poultry Research Station, Animal Production Research Institute, Agricultural Research Center, Dokki, Egypt during the period from November, 1992 to August, 1993.
It was divided into three experiments: the first one dealt with studying the effect of different calorie:protein ratios on the reproductive perfomance of rabbit does. The second trial was designed to determine the optimum calorie: protein ratio required for maximum growth of growing rabbits from 5 to 13 weeks of age. The third experiment included twelve digestion trials in order to determine the digestibility coefficients of nutrients and digestible energy of the experimental diets.
In the first experiment, a total of seventy two New Zealand white rabbit does 6 months old with average weight of 3.34 kg were used. Mating was achieved by 18 bucks with good fertility record and each doe gave two parities.
Experimental animals were assigned into 12 experimental treatments in which four levels of digestible energy (2400, 2500, 2600 and 2700 Kcal/kg) and three levels of crude protein (15, 17 and 19%) were used in 4 x 3 factorial design. Records were obtained during both gestation and suckling periods. In the second experiment, seventy two weaned unsexed rabbits (4 weeks of age) were randomly distributed into 12 experimental treatments of 6 rabbits each with an average weight of 530 g / group. Rabbits offered a commercial diet for about 7 days before starting the experiment. Then, they fed the forementioned 12 experimental diets having different calorie: protein ratios from 5 up to 13 weeks of age. This experiment aimed to determine the optimum C/P ratio required for maximum growth and feed conversion of growing New Zealand White rabbits. Records were also kept for slaughter characteristics, meat analysis and some blood parameters included total protein, albumin, globulin, NG ratio, total lipids and cholesterol. Moreover, at the end of this experiment the economical efficiency of meat production was calculated based upon the differences in both growth rate and feeding cost The third Part of this study included 12 digestion trials to determine the digestibility coefficients of nutrients and the feeding value expressed as digestible energy of the experimental diets used in the previous two experiments. The digestion trials were earned out using 36 mature New Zealand White male rabbits in 12 groups of 3 individually rabbits each of approximately similar live weight (3.0 kg).
The results obtained and conclusions derived could be summarized as follows:
1- FIRST EXPERIMENT:
A- Gestation period:
I - The shortest gestation length was achieved by rabbit does fed 2500 K
cal DE/kg versus 17%. CP or the diet having 147.1: I as CIP ratio.
Such diet recorded the lower feed intake values compared with other
treatments.
2- The diet contained 2600 K cal DE/kg versus 17% CP or 152.9 as CIP
ratio recorded the highest number of kits born alive and a sensible
gestation length which was not Significantly differ than that obtained
by the former diet contained 147.1 : 1 as C/P ratio.
B- Suckling period:
3- The best weight either at birth or at weaning was obtained by feeding
dams on diet containing 2700 K cal DE/kg and 19 % or 142.1: I as
calorie: protein ratio. Besides, rabbit does fed such diet gave the best
findings of feed conversion efficiency and the least mortality rate of
their kits.
11- SECOND EXPERIMENT (GROWTH AND FATTENING) :
4- The different levels of crude protein (15, 17 and 19%) had no
significant effect on live body weight and body weight gain values.
While, the values were affected significantly by digestible energy
levels. Growing rabbits received 2700 K cal DE/kg recorded the
highest live body weight and body weight gain values and the least
corresponding ones were obtained by those having either 2400 or 2500
K cal DE/kg.
5- The highest live body weight as well as body weight gain values were
obtained by growing rabbits fed diets containing 2700 K cal DE/kg
versus 19% CP or 142.1 : 1 as C/P ratio, while the least corresponding
values have been obtained by growing rabbits received diet with 2400
K cal DE/kg versus 19% CP or 126.3 : 1 as C/P ratio.
6- The best utilization efficiency of dietary energy and protein as well as
the best feed conversion efficiency were obtained by growing rabbits
having either 2500 K cal DE/kg versus 17% CP or 2600 K cal DE/kg
versus 19% CP or 2700 K cal DE/kg versus 19% CP, i.e., 147.1, 136.8
and 142.1 as calorie: protein ratio.
7- Rabbits fed diet contained 2600 K cal DE/kg and 19% CP or 136.8 as
C/P ratio recorded the highest percentages for dressing weight,
boneless meat and total edible parts.
8- The results cleared that the fat content of carcass increased, while the
moisture and protein content decreased using the highest C/P ratio
(180: I). As the CIP ratio became narrower (126.3: I), the protein and
moisture content of carcass increased at the expense of lowering fat,
accordingly, the physiological fuel value varied.
9- Feeding growing rabbits on diet containing 2600 K cal DE/kg versus
19% CP or 136.8 as C/P ratio results in decreasing the total lipids and
total cholesterol in their plasma to reach the corresponding values
obtained before feeding (at weaning). Such diet containing 136.8 : 1 as
C/P ratio had recorded the highest albumin content of plasma among
different experimental treatments.
10- The highest economical efficiency based upon the differences between
growth rate and feeding cost was obtained by growing rabbits
received the diet contained 2600 K cal DE/kg and 17% CP or 152.9 as
C/P ratio. However, diets with 19% CP versus 2600 or 2700 K cal
DE/kg (136.8 or 142.1:1 as C/P ratio) recorded the least costs
required to obtain one kilogram of live body weight or live body
weight gain.
Ill- THIRD EXPERIMENT (DIETS EV ALVA TION) :
11- The highest percentage of crude protein digestibility was achieved by
feeding rabbits on the diet containing 2600 K cal DE/kg versus 19%
CP or 136.8 : 1 as C/P ratio.
12- Practically, all experimental diets recorded approximately similar
findings of organic matter digestibility amounted to 70%. However,
the diet contained 2600 K cal DE/kg and 17% CP or 152.9 as C/P ratio
recorded the highest organic matter digestibility.
13- The feeding value as digestible energy showed slight differences
compared with the corresponding calculated values due to the slight
differences in feed intake within replicates of each treatment.
Moreover, the utilization efficiency of digestible energy increased
either as the dietary energy level increased up to 2600 K cal DE/kg
and then declined at 2700 K cal level, or by increasing dietary protein
up to 17% and declined at 19% level.
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| Publication year |
1995
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| Availability location |
مكتبة معهد بحوث الانتاج الحيوانى- شارع نادى الصيد -الدقى- الجيزة
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| Availability number |
504
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| Organization Name |
Animal Production Research Institute (APRI)
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| Country |
Egypt
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| Department |
Poultry Nutrition Research Department
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| Author(s) from ARC |
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| Agris Categories |
Animal feeding
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AGROVOC
TERMS |
Energy.
Growth.
Proteins.
Rabbits.
Reproduction.
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| Publication Type |
Master Thesis
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