الفهرس 
Abstract
The objectives of conducting this research work were as followsOnly 14 pages are availabe for public view
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Abstract
In the current research work different environmental factors that supposed to affect some different NZW rabbit behaviours & performances and act as stressors were studied. This were done by determining the effect of these factors in general rabbit behaviours & Ethogram, Buck and doe sexual behaviours, maternal behaviours, buck, doe and litter performances, measuring some hormonal parameters (corticosterone, estradiol (E2) and testosterone, haematological and biochemical parameters. The research were carried out in laboratory animal house Faculty of Veterinary Medicine Hospital, Assiut University, Assiut, Egypt. The current laboratory research work was done from July 2011 till December 2012.The environmental factors includes: contamination of drinking water with dibutyl phthalate (DBP) either in 500 or 750 mg/kg/day, food restriction either to take 25% or 50% of daily needed amount, water restriction for 12 or 18 hrs and heat stress.
The obtained results revealed the following:
6.1. Drinking Water Contamination with Dibutyl Phthalate
Significant increase of serum corticosterone level in oestrous doe, pregnant doe and buck rabbits exposed to either DBP of 500 or 750 mg/kg/day. This increase was dose-dependent as it was related to the increase in the concentration of DBP.
It was concluded that DBP acted as a physiological stressor when rabbits exposed to DBP by gavaging.
DBP exert stress on the buck than doe rabbits.
DBP led to significant decrease in both oestrous and pregnant doe serum E2 level.
Serum Testosterone level of buck rabbits was significantly lowered when animals gavaged DBP.
Drinking water contamination did not exert any considerable change in blood haematological and biochemical parameters except there is an evidence that DBP exposure affect immunity negatively by decreasing WBCs count. In addition, it led to an increase in serum inorganic calcium level.
Markedly DBP affected rabbit’s general behaviours and Ethogram. In one side, it considerably increased eating and drinking behaviours and in the other side, collectively DBP lower activity of rabbits. In other way, DBP lowered active behaviour and increases inactive, boredom and investigative behaviours beside it led to appearance of abnormal behaviours.
Male sexual behaviours was largely affected by DBP. While some parameters of doe sexual behaviours were affected, but receptivity was less affected.
Regarding maternal behaviour, pre-partum and post-partum behaviours and parameters was affected while there were no evidence of that partum behaviours were affected.
Exposure to DBP make rabbits remove their food hopper as a sign of abnormal behaviours.
Pups litter traits did not affected by DBP, except eye opening which take more time.
Concerning rabbit performances, DBP caused no mortalities in adult rabbits but decrease o weight gain and food intake was observed.
Although DBP did not have effect on litter performances at birth , it have affect negatively litter performances at weaning as increase mortalities, decrease litter size and survival rates and weights of rabbit pups.
6.2. Food Restriction
It was observed that significant increase of serum corticosterone level in oestrous doe, pregnant doe and buck rabbits exposed to either food restriction of 50 or 25%. This increase was amount-dependent as it was related to the increase in the decrease of food amount.
It was concluded that food restriction acted as a physiological stressor.
Food restriction led to significant decrease in both oestrous and pregnant doe serum E2 level.
Serum testosterone level of buck rabbits was significantly lowered when bucks exposed to food restriction.
The decrease of both E2 and Testosterone was dependent in the amount of restricted food.
Food restriction exert a considerable change in blood haematological parameters, where there were considerably decrease WBCs, lymphocytic count, lymphocyte%, MCV and PLT. This was a reflection that food restriction led to decrease immunity and induce anaemia in food restricted rabbits.
In addition, food restriction did not show any change in biochemical parameters except there is an evidence that food restriction led to an increase in serum inorganic calcium level and phosphorous level.
Definitely food restriction affected rabbit’s general behaviours and Ethogram. In one hand, considerable decrease in body maintenance, eating, drinking, investigative and active behaviours. In the other hand, collectively food restriction raise total inactive behaviours especially boredom and appearance of abnormal behaviours.
Respectful decline of both male and female sexual behaviours in response to food restriction. Plus, receptivity and conception rate were reduced clearly.
Interestingly maternal behaviour, pre-partum and post-partum behaviours and parameters were distinctly fallen off markedly.
Food restriction give rise to abnormal maternal behaviours in rabbits as cannibalism, pup scattering, throwing food, removal of food hopper and pup abundance.
Extensive effect of food restriction was observed in time of eye opening, ear opening, time of pup’s exit out of nest boxes and nipple food .In addition, severe leg abnormalities were appeared clearly at 45th day age.
Concerning rabbit performances, food restriction caused no significant mortalities in adult rabbits but decrease on weight gain and food intake was observed.
Further food restriction had severe negative effect on litter performances both at birth and weaning.This include mortalities, litter size,survival rates and weights of rabbit pups.
6.3. Water Restriction
Powerful increase of serum corticosterone level in oestrous doe, pregnant doe and buck rabbits exposed to different water restriction regimes. This increase was period-dependent as it was related to the increase in the period of water restriction.
It was certified that water restriction acted as a physiological stressor.
Water restriction exert stress on pregnant doe than buck and oestrous doe rabbits.
Water restriction led to significant decrease in both oestrous and pregnant doe serum E2 level.
Serum testosterone level of buck rabbits was significantly lowered when bucks exposed to water restriction.
Water restriction did not exert any considerable change in blood haematological and biochemical parameters except there is an evidence that water restriction exposure affect immunity negatively by decreasing WBCs count and lymphocyte percent. In addition, it led to an increase in serum inorganic calcium level and phosphorous level.
During water restriction period marked effects of rabbit’s general behaviours and Ethogram were occurred. In one side, it considerably decreased in body maintenance and eating behaviours. In the other side, collectively water restriction lower activity of rabbit’s .in other way, water restriction lowered active behaviour and increases inactive and boredom .Plus, abnormal behaviours and others behaviours were appeared significantly.
Seriously both male and female sexual behaviours were badly affected by water restriction. Additionally, total receptivity and conception rate were reduced powerfully.
Pronounced depression of maternal behaviour, pre-partum, partum and post-partum behaviours.
Water restriction give rise to abnormal maternal behaviours in rabbits as cannibalism, pup scattering, throwing food, removal of food hopper and pup abundance.
Some pups litter traits were affected by water restriction as eye opening and time of exit out of nest boxes and nipping food.
Concerning rabbit performances, water restriction caused no mortalities in adult rabbits but decrease of weight gain and food intake was observed.
Water restriction have negatively affect litter performances both at birth and weaning. By increase mortalities, decrease litter size, survival rates and weights of rabbit pups.
6.4. Heat Stress
Rabbits were exposed to high temperature at temperature humidity index (THI) of 28.08, which considered as severe heat stress condition.
It was concluded that HS acted as a physiological stressor which led to significant increase of serum corticosterone level in oestrous doe, pregnant doe and buck rabbits.
Pregnant does was more affected by HS than buck and oestrous doe rabbits.
HS led to significant decrease in both oestrous and pregnant doe serum E2 level.
Serum testosterone level of buck rabbits was significantly lowered when exposed to HS.
Heat stress did not exert any considerable change in blood haematological parameters but marked effect on the biochemical parameters was observed as decrease serum total protein and albumin and increase in serum inorganic calcium and phosphorous.
Markedly HS affected rabbit’s general behaviours and Ethogram. In one side, it considerably decreased eating, active and investigative behaviours and in the other side, collectively HS lower activity of rabbit’s .in other way, HS lowered active behaviour and increases body maintenance, drinking, inactive behaviours, boredom and abnormal behaviours.
Both Male and female sexual behaviours was seriously affected by HS. Also, receptivity and conception rate were markedly decreased.
Regarding maternal behaviour, pre-partum, partum and post-partum behaviours were seriously diminished.
Some abnormal maternal behaviours were appeared as response to heat stress as pup scattering, throwing the food, remove the food hoppers and pup abundance.
Pups litter traits did not affected by HS, except the earlier exit of pups out of nest boxes and nipple food.
Concerning rabbit performances, HS caused no mortalities in adult rabbits but decrease o weight gain and food intake was observed.
Obviously HS have lowered litter performances both at birth and weaning, it have affect negatively litter performances at weaning as increase mortalities, decrease litter size and survival rates and weights of rabbit pups.