Effect of Testosterone Enanthate Injection and Castration on some Productive Traits of Karadi Lambs

1 M. A. Ishak, 2 C. A. Omar
1 Department of Animal Resources, College of Agriculture, University of Baghdad, 2 Department of Animal production, Faculty of Agricultural Sciences, University of Sulaimani

This study was conducted to investigate the influence of testosterone enanthate
injection on some productive characteristics of Karadi lambs. This experiment was
carried out at the Sheep Farm, belong to the Faculty of Agricultural Sciences, University
of Sulaimani, Bakrajo. Thirty six Karadi ram lambs, aged 3-4 months and average live
weight of 28.7±3.8 kg were randomly divided into three equal groups. Six ram lambs from
each group were castrated using elastrator and rubber ring, two weeks before beginning
of the experiment. First group was left as control group without treatment (T1). The
second group (T2) was injected weekly with 200 mg of testosterone enanthate (TE)/ram
lamb. The third group (T3) was injected with 400 mg TE/ram lamb weekly until the
termination of the experiment. The TE injections as anabolic agent were given weekly to
each treated lamb to investigate its effect on some productive and physiological traits as
well as their residual effect, over the period from 18th May to 30th August 2010. Lambs
were fed as (3%) of live body weight. The allowance was readjusted at weekly intervals
according to live weight. Live body weight (LBW)(Kg), live weight gain(LWG)(%),
average daily gain (ADG) (gm/day), dry matter intake (DMI)(gm/day) and feed
conversion ratio (FCR)(gm DMI/gm gain) were determined. Results indicated that ADG
of intact lambs in the control group, low and high level of TE groups, were higher than
the castrated lambs at 4 months of age. The castrated lambs in T2 had higher ADG at 4,
5, 6, 7 and 8 months of age as compared with castrated lambs in T1 and T3 groups.
Higher DMI was recorded for the intact lambs of the control, low and high level of TE in
comparison with castrated lambs. Results revealed that castrated lambs of the control
group had higher FCR at 4,5,6 and 8 months of age as compared to intact lambs (4.06 vs.
3.46, 6.56 vs. 6.41 , 6.96 vs. 5.85 and 5.96 vs. 5.27 gm DMI /gm gain), while the FCR
increased in the intact lambs treated with 200 mg TE as compared to castrated lambs at
4,5,6 and 8 months of age (4.00 vs. 3.69, 4.94 vs. 3.93, 5.62 vs. 4.14 and 6.47 vs. 5.44 gm
DMI/gm gain), respectively. We concluded that castrated lambs treated with 200 mg TE
have higher ADG as compared with other experimental groups.

Keywords: Karadi ram; castrated lambs; intact lambs; TE; ADG; DMI.


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