PRODUCTIVE AND REPRODUCTIVE PERFORMANCE OF RABBITS FED DIETS SUPPLEMENTED WITH ZINC-METHIONINE

A total number of three hundreds and twenty four
Californian(Cal) rabbits was used in the present work to study some
productive and reproductive performance of growing and mature
rabbits as influenced by supplementing Zinc-Methionine to the diets.
The present study included two experiments. The first
experiment was lasted 40 days and carried out during growing period
on 230 weaned Cal rabbits aged 30 days. The second experiment was
lasted 4 months and carried out on 80 monoparous does and 14 sexual
mature bucks of Cal rabbits aged 6 months. All rabbits in two
experiments were divided into two equal comparable experimental
groups (115 growing rabbits, 7 bucks and 40 does in two sequence
parities in each group). The first group was kept untreated (as a
control group) and fed the commercial diet, while the other group
(treated group) was fed the same diet and supplemented with 400 gm/
Ton Zinc-Methionine (ZM), during the experimental period. The
pelleted rations fed to the experimenta lrabbist were covering the
nutritional requirements of the growing and mature phase of rabbits..
The results obtained revealed that, daily body weight gain , feed
efficiency and feed conversion values of growing Cal rabbits fed diet
PRODUCTIVE AND REPRODUCTIVE PERFORMANCE104
supplemented with 400 gm/ Ton Zinc-Methionine significantly
(P≤0.05) improved. Daily feed intake was insignificantly higher than
those of control group. Feeding diet supplemented with 400 gm/ Ton
Zinc-Methionine increased significantly (P≤0.05) dressing % and
carcass and internal organs weight (absolute and relative) represented
by weights and percentages of each of spleen; kidneys; liver; heart and
lungs, as well as, blood picture of growing Cal rabbits represented by
(red and white blood cells count; hemoglobin concentration and
hematocrite percentage) and some blood constitute such plasma total
protein and its fractions (albumin; globulin and albumin/ globulin
ratio). Some enzymes indicated liver activity of growing Cal rabbits
represented by values of each of glutamic-oxaloacetic transaminase
(GOT) and glutamic-pyruvic transaminase (GPT) also increased
significantly (P≤0.05) due to supplementation of 400 gm/ Ton Zinc-
Methionine to the diet.
Supplementing 400 gm/ Ton Zinc-Methionine to the diet of the
Cal rabbit bucks improved significantly (P≤0.05) their reproductive
capability represented by libido and physical semen quality (semen-
ejaculate volume; advanced-sperm motility; live and normal
spermatozoa; acrosome status and sperm-cell concentration per ml and
per ejaculate); gonads and pituitary gland weight; scrotal
circumference and testicular index. Testosterone concentration and
mating activity of Cal rabbit bucks ate diet supplemented with 400
gm/ Ton Zinc-Methionine were significantly (P≤0.05) higher than
those of fed without Zinc-Methionine (control group).
Cal rabbit does fed diet contained 400 gm/ Ton Zinc-Methionine
and mated naturally by using bucks fed the same treated diet recorded
kindling rate, litter size and weight at birth; milk yield and pre-
weaning mortality rate significantly (P≤0.05) better than those of
received untreated diet (control group).
It can be concluded that supplementation 400 gm/ Ton Zinc-
Methionine to Cal rabbit diet showed a great role in enhancing the
immune system, improved growth performance, blood metabolites
and reproductive performance. From the economic point 400 gm/ Ton
Zinc-Methionine is recommended for both growing and mature (bucks
+ does) rabbits.