الفهرس | Only 14 pages are availabe for public view |
Abstract An expex!m6Dt was ccxxied out at the Experimental Farm of the Faoulty of Agricultural Sciences at Moshtohor, Qalyoubin Governorate, to study the effect of feeding urea and some other environme.:” al factors all. individua.l weight” daily gain, livability and litter traits in Bauacat and Giza White rabbits” Animals used comprised 62 Bauscat and 57 Giza White rabbits, ranging from 11 to 24 weeks of age at the beginning of the expeximent. Results could be summarised as follows: 1- Daily gain a?d= body weight of rabbi t~: A- Rabbits fed th3 diet containing urea showed lower daily gain and body weights than those fed a diet without urea. For the average daily gain, the differences were significant (p .0.05) during the periods from 11-16 to 20 weeks and from 20 to 24 weeks only. But for body weight, the differences were gene~ally significant except at 28 weeks of age. B- B.eed group differences did not contribute significantly to the total variance of either dailY gain or body weight at the different stages and ages stUdied. Also, no consistent trend for b~eed effects were detected. C- Daily gain in.weight during the four stages of the study as well as body weight varied with age at the start of the experiment. The differences among age groups were not significant for the average daily gain while were signifioant for body weight at 24 and 28 weeks of age only. ” D- Rabbits born during January and February surpassed those born during March and April in the average daily gain during the different stag~s, while the reverse was true for body weight at the different ages studied. Differences due to time of birth 10 average daily gain. did not attain sign.i:ficance at any of the studied stages, but they proved to be significant for body weight at 24 weeks only. B- The average daily gain i.a females was always higher than that in males, the differences were not statistically significant. Also, females were found to be heaVier than males at all ages stUdied, but the differenoes between the two sexes were significant at 20 and 24 weeks of age. F- Average daily gain during the different stages of the study as well as body weight of the rabb1ts was foun.d to be genexa11y positively associated with their initial weight. Initial weig~t was found to be a negligible source of variation in the average daily gain while being e.signifioant source of variation in. body weight of rabbits at 20, 24 and 28 weeks of age. 2- Livability of individual .rabbits: A- Using diet with urea caused an inoxease in the livability of rabbits during the experimental period tillthey reaohed either 28 or 32 weeks of age. Differences between livability of rabbits fed diet with urea and that of rabbits fed diet without urea were not significant. B- Giza Whit€ rabbits showed more livability than Bausc~t rabbits up till either 28 or 32 weeks of age, but the differences were not significa.nt (P·O.5). c- Livability of rabbits deozeased significantly during the experimental period with the increase of age of rabbit at starting the erperimant. D- Rabbits born du.rillg Jaunary and Feb.ruary survived more than those born duxing MarCh and Apr11. The differences were significant (P .0.01) at 28 weeks of age While being non-significant at )2 weeks o-f age. E- Sex was not found to be a sginficant source of variation in livability of zabbits. F- Livability of the J.-abbitswas found to be positively assooiated with initial body weight. Initial weight affects were signifioant at 28 weeks of age While being non-significant at 32 weeks of age. 3- Litter size ~d litter weight: A- Litters born by dams fad urea in the diet was larger and heaVier than those born by dams fed the o611trol diet (basal diet without urea) at birth and at wean1.ng at 5 weeks of age. Feeding type was not found to be a considerable SOQliOS of variation in. these traits. B- Giza White litters .recorded larger size and weights than Bau8cat litters and in gene.ral continued to show . - the same trend up to weaning. Breed group differences did not contribute signific8.l1tly 1.n the total variance of litter size and litter weight at birth and up to weaning. C- Fffect of age of dam at the start of the experiment dis not significantly influence the size of th81r 1i tters at all the ages stUdied. The same t.rend was also observed for litter we1ght at 2 weeks of age and a t we an.1Llg only. |