الفهرس 
Materials and mithodsOnly 14 pages are availabe for public view
 |  | from | 125 |  |  |
| | | from | 125 | | |
Abstract
The present study was carried out at Animal House of the National Organization for Drug Control and Research (NODCAR), Agouza, Cairo, at the period from 3/3/1997 .to 25/10/1997.
This study was planned to investigate the effect of an anabolic steroid (methyl-A-androstenolone oenonthate, MA) and two antibiotics (amoxicillin, Amox and danofloxacine, Dano) used either individually or together on the performance, mortality rate, nutrients digestibility, carcass traits and some biochemical parameters of blood serum of growing NZW rabbits during the period from 5 to 16 weeks of age.
A total of 96 weaned NZW rabbits aged five weeks old with an average initial live body weight of 600 g were used in this study. Rabbits were randomly distributed into eight groups of 12 rabbits each with nearly similar body weight. Each group of rabbits was randomly assigned to one of the following experimental treatments.
1 - Untreated control group.
2 -Methyl-A-androstenolone oenonthate (MA) treated group, 10 mg/kg BW by intramascular injection at the start and every two weeks thereafter.
3 - Amoxicilline (Amox) treated group, 2 g/litter drinking water.
4 - Danofloxacin (Dano) treated group, 0.3 g/litter drinking water.
5 —MA+Amox treated group, MA (10 mg/kg I3W every two weeks) plus Amox (2 g/litter drinking water).
6 — MA+Dano treated group, MA (10 mg/kg 13W every two weeks) plus Dano (0.3 g/litter drinking water).
7 — Amox+Dano treated group, Amox (2 g/liter drikng water) plus Dano (0.3 g/litter drinking water).
8 —MA+Amox+Dano treated group, MA (10 mg/kg BW every two weeks) plus Amox (2 glitter drinking water) plus Dano (0.3 g/litter drinking water).
The experimental basal diet . used in this study was formulated to ensure adequate supply of all nutrients recommended by NRC (1977) and Cheeke (1987) for growing rabbits. It contained 2824 kcal DE/kg diet, 17.70% CP and 12.61% CF.
Rabbits were individually housed in galvanized wire cages and fed the experimental basal diet in pelleted form ad libitum with fresh water up to 16 weeks of age. Rabbits were individually weighed every week before offering morning meal.
At the termination of the experimental period, a digestibility trial was carried out to determine the effect of experimental treatments on the digestibility of feed nutrients of the basal diet using 4 male rabbits from each treatment. Blood samples were withdrawn from the retro-orbital plexus of 8 rabbits of each treatment at 12 and 16 weeks of age to determine some biochemical parameters of blood serum. Eight representative rabbits from each treatment were randomly taken at 16 weeks of age to study carcass traits.-
Results obtained could be summarized in the following :-
1-At the termination of the experimental period (16 weeks of age), rabbits of MA treated group recorded the highest BW and daily WG followed by those of MA+Amox+Dano, MA+Amox and MA+Dano treated ones. Whereas, rabbits of the control group showed the lowest BW and daily WG. The differences in BW between all treated groups were not significant except those between rabbits of the MA, MA+Amox+Dano, MA+Amox and MA+Dano treatments and the control group. Whereas, those in daily WG between the control group and all other treated ones were significant (P<0.05) except for Amox and Amox+Dano treated groups.
2-Values of daily FI during the whole experimental period (5-16 weeks of age) showed that rabbits of the control group consumed the lowest daily FI, while values for other treated groups varied slightly but with no significant differences.
3-Results of the whole experimental period (5-16 weeks of age) indicated that the best (P<0.05) FC value was achieved by rabbits of MA treated group, followed by those of MA+Amox+Dano, MA+Amox and MA+Dano treated groups, with no significant differences between these treatments. Whereas, rabbits of Amox+Dano and the control treated groups exhibted the poorest FC values, followed by those of Amox and Dano treated groups each alone. No significant differences were detected in FC values among the previous four treated groups.
4-In general, treatments of MA alone or in combination with Amox or both Amox and Dano increased mortality rate of growing NZW rabbits during the experimental period (5-16
weeks of age), whereas those of either Amox or Dano, each alone or in combination, decreased mortality at the same period. However, no mortality was detected with the MA+Dano treated group during the experimental period.
5-Results of digestibility showed that the differences in DM, OM, CP, CF and NFE digestibilities due to treatment effects were not significant. However, dietary treatments, generally, improved the digestibility of OM, CF and NFE but with no significant differences, whereas it significantly (P<0.05) improved EE digestibility.
6-Dietary treatments had little effect on absolute and relative (%) weights of carcass traits of growing NZW rabbits at 16 weeks of age and the differences due to treatment effects were almost not significant.
7-Chemical analysis and physiological fuel values of boneless meat of growing NZW rabbits at 16 weeks of age showed that dietary treatments had no effect on DM, CP and ash contents, whereas, rabbits of MA+Dano and Amox+Dano treatments recorded the highest EE% and those of Dano and control treatments represented the lowest contents, the differences were significant. The highest physiological fuel values were achieved by rabbits of Dano treatment and the lowest ones were recorded by those of Amox treatment, with significant differences between the two treatments.
8-In general, Amox+Dano and MA+Amox+Dano treatments tended to increase the level of most blood serum contents of growing NZW rabbits at 12 weeks of age, while triglycerides decreased (P<0.05) in serum of all treated rabbits as
SUMMARY & CONCLUSION -83-
compared with that of the control. At 16 weeks of age, MA treatment showed the greatest effect on blood serum constituents of treated growing NZW rabbits, whereas tiglycerides and total lipids decreased in all treated rabbits as compared with those of the control group. However, the differences in blood serum constituents among the two ages (12 and 16 weeks of age) of growing rabbits were limited and all values are within the ranges for serum (or plasma) biochemistry values of rabbits reported by many investigators at similar ages.
It could be concluded that treatments of MA either alone or in combination with Amox and /or Dano improved most of the growth performance traits, nutrients digestibility and carcass traits of growing NZW rabbits, but further studies are needed to study the economic benefits of such materials in commercial rabbits diets when used as feed supplements or in drinking water.