The effect of trenbolone acetate on growth rate and carcass composition of young female rabbits

1983 ◽  
Vol 36 (1) ◽  
pp. 111-115 ◽  
Author(s):  
G. E. Lobley ◽  
A. Walker ◽  
Alexmary Connell ◽  
H. Galbraith

ABSTRACT1. Eighteen New Zealand White × Califomian young female rabbits (does) were paired by weight and age and, at 800 g live weight, placed on a restricted intake based on the mean body weight of each pair. On attaining 1 kg one of each pair was then given 10 mg trenbolone acetate by injection on days 1, 3 and 5 of each week. This continued until the animals reached 2·3 to 2·4 kg (5 to 6 weeks).2. There were no differences in digestible or metabolizable energy intakes between treated and untreated rabbits. However, the treated animals showed small but significant increases in rates of gain for live and empty body weight compared with control does. Treated animals also had significantly more nitrogen (P < 0·001) and less energy (P < 0·05) per unit empty body weight than controls. Although the proportion of total nitrogen retention was 0·19 greater (P < 0·001) in treated does, total energy retention was only slightly less. Treated animals had approximately 40 g (200 g/kg) less fat and 50 g more protein (N × 6·25) than control does at the end of the trial.3. Increases in liver weight and clitoral size were observed in treated animals.

1982 ◽  
Vol 34 (3) ◽  
pp. 309-314 ◽  
Author(s):  
T. W. Griffiths

ABSTRACTTwenty-four castrate male cattle were used in two nutritional balance and slaughter experiments to measure the effects of two implantations with 300 mg trenbolone acetate and 36 mg resorcylic acid lactone over the live-weight range 250 to 400 kg. Control and implanted animals were pair-fed barley-based diets of differing protein concentration in the first experiment and the lower protein diet at two levels of feeding in the second experiment.Daily live-weight gain and nitrogen retention were significantly increased by implantation in both experiments. The carcasses of implanted animals contained significantly more lean meat and a higher proportion of meat in the forequarter. The edible portion of these carcasses contained significantly more protein and water and less fat.Live-weight gain and carcass composition were not influenced by dietary protein intake. Increased feeding level improved live-weight gain, suggesting that a higher metabolizable energy intake would give an increased response to implantation.


1979 ◽  
Vol 93 (2) ◽  
pp. 321-327 ◽  
Author(s):  
W. Little ◽  
R. M. Kay ◽  
D. J. Harwood ◽  
R. J. Heitzman

SUMMARYTwenty-seven British Friesian heifer calves were housed as a group but fed individually barley-lucerne pellets according to a scale related to body weight. At 16 weeks and again at 31 weeks of age nine calves were implanted subcutaneously at the base of the ear with 300 mg trenbolone acetate (group T), nine calves were similarly implanted with 140 mg trenbolone acetate and 20 mg oestradiol-17/? (group TE) and the remaining nine calves were sham implanted (group C).As a result of increased feed conversion ratios, body-weight gains were significantly greater in group T (0–80 kg/day) and group TE (0–87 kg/day) than in group C (0–72 kg/ day) during the 15 weeks following the second implant, but there was no significant difference between groups following the first implant.Following both implants in groups T and TE the mean concentrations of urea and albumin in serum decreased, and that of globulin increased. The mean urea: creatinine ratio in the urine of animals in groups T and TE relative to that in group C also decreased.The heifers were served by an Aberdeen Angus bull at the first and, when they occurred, subsequent oestruses. Following calving the mean milk yields in the first lactation in group T (641 kg in 96 days) and group TE (1993 in 212 days) was considerably lower than in group C (3636 kg in 293 days). The udder size in both groups of animals treated with the anabolic steroids was markedly reduced. It is concluded that despite an improvement in feed conversion ratios and body-weight gains, trenbolone acetate should not be administered to prepuberal heifers which will be retained for breeding and milk production.


1970 ◽  
Vol 75 (2) ◽  
pp. 327-335 ◽  
Author(s):  
T. A. McCullough

SUMMARYConcentrate diets supplemented with 5, 20 and 40% of a high- and a low-quality hay were given ad libitum to British Friesian steers from 9 weeks of age to slaughter. The intake of dry matter and metabolizable energy was studied over weight ranges from 91 to 363 kg live weight. The quality of hay did not significantly affect the drymatter intake at any of the weight ranges studied. From 91 to 182 kg live weight the daily dry-matter intake decreased as the proportion of hay in the diet increased. Over the weight range from 182 to 272 kg live weight, intake was maximum at the 20% level of hay supplementation, while from 272 to 363 kg live weight, intake increased with increasing levels of hay in the diet. The supplementation of high-quality hay significantly increased the intake of metabolizable energy by animals weighing 91–182 kg. Increasing proportions of hay in the diet significantly affected the metabolizable energy intake at all stages of growth studied.At 18 and 36 weeks of age digestibility and N balance studies were carried out. The metabolizable energy expressed as a percentage of the gross energy and the mean retention time of the diets were significantly affected by the age of animal, quality of the hay and the level of hay supplementation. Nitrogen retention was also affected by the age of the animal but not by the quality of the hay.The relationships between the voluntary intake of dry matter and the metabolizable energy of the diet expressed as a percentage of the gross energy, for different stages of growth, are also presented.The change in the digestibility and the mean time of retention of the diets in the digestive tract with age and the effect of this on the point where physical regulation to intake gives way to physiological regulation are discussed.


1992 ◽  
Vol 54 (2) ◽  
pp. 259-264 ◽  
Author(s):  
R. W. Benjamin ◽  
E. Oren ◽  
E. Katz ◽  
K. Becker

AbstractAn in vivo digestibility trial was conducted by feeding sheep the leaves, fruits and twigs of Atriplex barclayana in a proportion roughly equivalent to that eaten by sheep grazing freely in Atriplex plantations. Four treatments were imposed on each of four sheep in a 4 × 4 Latin-square experimental design: Atriplex offered alone or with 100, 200 or 300 g/day tapioca meal.The mean apparent digestibility of the Atriplex dry matter (DM) and organic matter (OM) consumed were 0·59 and 0·56, respectively. Addition of tapioca to the Atriplex in the diet did not improve these digestibility coefficients. The low OM content of 760 g/kg together with its digestibility of 0·56 resulted in the Atriplex having a low metabolizable energy concentration of 6·28 MJ per kg DM. The in vitro apparent DM digestibility of Atriplex was approximately 0·09 higher than the in vivo apparent digestibility.The mean nitrogen concentration of the Atriplex DM was 16·6 g/kg, and its apparent digestibility 0·73, which was not improved by the addition of tapioca to the diet. Nitrogen retention of the sheep eating only Atriplex was proportionately 0·17 of the nitrogen intake. The addition of 300 g tapioca improved nitrogen retention to 0·27 but was not significantly different from the other treatments.Water intake and urine excreted were as high as 14 and 12 I/day respectively, for an Atriplex DM intake of about 1300 g/day. During the experiment the sheep only maintained live weight, despite daily intakes of up to 1200 g Atriplex DM and up to 300 g tapioca.


1990 ◽  
Vol 64 (3) ◽  
pp. 639-651 ◽  
Author(s):  
Isabelle Ortigues ◽  
T. Smith ◽  
M. Gill ◽  
S. B. Cammell ◽  
N. W. Yarrow

Thirty-two 160 kg dairy heifers were used to measure the effects of increasing dietary protein content on growth and heat production. A basal diet containing (g/kg) 550 sodium hydroxide-treated straw, 220 barley, 220 sugarbeet pulp and 10 urea was offered with 0, 76 and 152 g fishmeal/kg dry matter of the basal diet (F0, F1 and F2 levels respectively). The three diets were each given at two levels of feeding (low, L; high, H): 57.6 g/d per kg metabolic body-weight (W0.75) for the LF0 diet and 74.7 g/d per kg W0.75 for the HFO diet. Apparent digestibility of the diets increased in response to the addition of fishmeal. Mean dry matter digestibility values were 0.67, 0.67, 0.69, 0.66, 0.68 and 0.69 and those for acid-detergent fibre digestibility were 0.60, 0.63, 0.66, 0.58, 0.60 and 0.65 for diets LF0, LF1, LF2, HF0, HF1 and HF2 respectively. Nitrogen retention increased in response to both fishmeal and feeding level. Live-weight gains were 170, 296, 434 g/d for the LF0, LF1 and LF2 diets and 468, 651 and 710 g/d for the HF0, HF1 and HF2 diets respectively. There were significant effects of increasing the plane of feeding and the level of fishmeal in the diet on live-weight gain. Dietary effects on live-weight gains were accompanied by increases in mean energy retention of 23, 45, 82, 94, 160 and 152 kJ/d per kg W0.75 for diets LF0, LF1, LF2, HF0, HF1 and HF2 respectively, but no definite evidence was obtained that dietary supplementation with fishmeal modified the efficiency of utilization of metabolizable energy for growth.


1975 ◽  
Vol 55 (4) ◽  
pp. 683-695
Author(s):  
W. S. ALHASSAN ◽  
J. G. BUCHANAN-SMITH ◽  
T. D. BURGESS ◽  
G. C. SMITH ◽  
G. C. ASHTON

One hundred and forty-four steers of predominantly Angus breeding were used to compare the effects of three housing units (conventional semi-enclosed manure pack, semi-enclosed slatted floor and enclosed–insulated slatted floor) and two diets (high moisture corn and corn silage) on the performance, energy metabolism and carcass composition of steers finished for 88 days in the summer. No diet × housing unit interaction on response criteria was observed. The mean temperature in the enclosed unit (24.6 C) was more than 3 C greater than in other units. Mean relative humidities in each slatted floor unit were 74% whereas it was 70% in the conventional unit. The enclosed–insulated unit may have been insufficiently ventilated. Steers in this unit ate less (P 0.05) dry matter per day (6.78 kg) than those in the semi-enclosed slatted floor unit (7.64 kg) and in the conventional unit (7.66 kg). Different effects of housing unit on gain reflected differences in feed intake. Carcass characteristics of cattle from each housing unit were similar (P 0.05). Efficiency of utilization of metabolizable energy (ME) for maintenance and gain expressed as energy retention (ER) adjusted to equal ME intake was greater (P 0.05) for cattle in the semi-enclosed slatted floor unit (5.17 Mcal/day) than in the insulated–enclosed unit (4.36 Mcal/day). ER adjusted to equal ME intake for steers in the conventional unit was 4.76 Mcals/day. Serum tetra-iodothyronine (T4) levels were similar (P 0.05) for cattle in all housing units, but were depressed in all cattle during a period of the warmest weather. Corn-fed steers ate significantly less dry matter and had significantly greater gain and feed efficiency than silage-fed steers. Backfat thickness was greater (P 0.05) for corn-fed versus silage-fed steers but this difference disappeared when values were adjusted to equal carcass weight.


1981 ◽  
Vol 32 (3) ◽  
pp. 261-266 ◽  
Author(s):  
J. F. S. Coelho ◽  
H. Galbraith ◽  
J. H. Topps

ABSTRACTNine Cheviot × Shetland castrated male lambs from a group of 24 of 28 kg initial live weight, were subcutaneously implanted with a combination of 60 mg trenbolone acetate and 12 mg oestradiol-17β at 105 days and again at 45 days before slaughter. Of the remaining lambs, nine were untreated and six were slaughtered at the start of the experiment as part of a comparative slaughter procedure. The lambs treated with the anabolic preparation grew significantly faster (P < 0·05), converted food to live weight and estimated carcass gain more efficiently, had heavier carcasses which were larger, and had greater estimated gains for protein, moisture and ash. Implanted animals also tended to have a smaller deposition of carcass and kidney fat, but significantly heavier kidneys and less wool when the latter three weights were related to empty body weight. The mean values for plasma urea and serum total protein as indicators of protein metabolism were significantly decreased and increased respectively in treated lambs, but no other significant differences in blood metabolites and hormones were recorded. A significant increase in teat length of implanted lambs indicated the oestrogenic nature of the anabolic preparation.


1971 ◽  
Vol 13 (4) ◽  
pp. 653-660 ◽  
Author(s):  
J. J. Robinson ◽  
C. Fraser ◽  
Elizabeth L. Corse ◽  
J. C. Gill

SUMMARYTwenty-one Finnish Landrace × Polled Dorset Horn female sheep approximating 8 months old were individually penned from 3 to 4 weeks after mating until parturition. They were allocated to one of three diets containing either 12·3, 14·1 or 16·5% crude protein and 2·1 Meal metabolizable energy per kg dry matter, offered at a level of 85 g/kg W0·75 per day. A series of nitrogen balance trials was carried out on all lambs during the last 100 days of gestation.The mean age at parturition was 382 days and the mean litter size 1·52. The live-weight gain (mean value 152 g/day) was not significantly affected by the level of protein intake. There was a tendency (005 < P < 0·10 for singletons) for lamb birth weight to decrease and the body-weight change of the dam to increase with increasing protein concentration in the diet. There was a significant linear increase in nitrogen retention both with stage of gestation and level of protein intake.The partition of nitrogen between the foetal and maternal body is discussed in relation to the estimated nitrogen content of the maternal live-weight gain.


1970 ◽  
Vol 75 (2) ◽  
pp. 337-345 ◽  
Author(s):  
T. A. McCullough

SUMMARYConcentrate diets supplemented with 5, 20 and 40% high- and low-quality hay were given ad libitum to British Friesian steers from 9 weeks of age to slaughter.The performance of the animals was studied over 91 kg weight ranges from 91 to 363 kg live weight and from 9 weeks of age to slaughter. In the whole experimental period the daily live-weight gain was significantly greater on diets containing high-quality hay. There was also an increase in the daily live-weight gain in each of the weight ranges studied on diets supplemented with high-quality hay but this increase was not significant at the stage of growth from 272 to 363 kg live weight. As the level of concentrate in the diet increased there was a significant increase in the daily live-weight gain at each stage of growth studied and over the complete experimental period.The mean feed conversion ratio was greater for diets containing low-quality hay. Except during the stage of growth from 272 to 363 kg live weight the proportion of hay in the diet significantly affected the mean concentrate conversion ratio. With increasing levels of hay in the diet there was a significant increase in the total dry-matter conversion ratio.The conversion ratio of metabolizable energy was also increased on diets containing low-quality hay. The proportion of concentrate in the diet significantly affected the conversion ratio of metabolizable energy at all stages of growth studied.There were significant differences in the killing-out percentages, weight and contents of the reticulo-rumen and the omasum plus abomasum expressed as a percentage of empty body weight, with increasing levels of hay in the diet. These measurements were not significantly affected by the quality of hay in the diet.Indirect measurements of carcass composition indicated that the level of hay in the diet tended to affect the amount of fat in the carcass but the amount of lean was similar at the different ratios of concentrate to hay. The ratios of the weight of separable lean to the weight of separable bone in the 9–10–11th rib cut were similar at different levels of hay supplementation. The organoleptic appraisal of sample joints indicated that carcass quality was satisfactory.


1981 ◽  
Vol 45 (3) ◽  
pp. 579-586 ◽  
Author(s):  
M. J. Lawlor ◽  
S. P. Hopkins

1. Studies were conducted to measure the influence of perinatal undernutrition of twin-bearing ewes on ewe milk yields and lamb performance in early lactation. Comparative studies were conducted with lambs to measure the effects of postnatal nutrition on lamb performance and carcass composition. The major objective of this work was to determine the extent of the influence of postnatal nutritional deprivation of lambs.2. From 8 weeks prepartum to 4 weeks postpartum each of forty twin-bearing ewes was given daily 0.30 MJ of ME/kg body-weight (W)0.75. Measurements were made of ewe body-weight changes, milk yields during the first 4 weeks of lactation, and of lamb performance.3. There were three postnatal experiments with lambs of ‘light’ and ‘normal’ birth weights, wcaned from the ewes at 72 h. One hundred and four lambs were used and they were individually reared on separate allowances of lamb milk-substitute for 8 weeks. They were subsequently given a lamb concentrate ration. In Expts 1 and 2 the lamb concentrate was fed ad lib. to ‘slaughter’ live weight. In Expt 3 the concentrate was restricted for 8 weeks post weaning and then fed ad lib. A carcass analysis (bone, muscle, fat content) was conducted on all lambs after slaughter. In the first experiment, half the lambs were slaughtered at 8 weeks of age on being weaned off the milk substitute, and a carcass analysis was carried out.4. The mean net body-weight loss per ewe from commencement of late pregnancy to 28 d post partum was 23.8 kg. The over-all mean daily milk yield was 843 g/d. The mean growth rate of the lambs was 97 g/d during the 4-week measurement of ewe milk yields.5. Live weight gain of lambs subjected to restricted milk-substitute allowance (125 g/dry matter (DM) per d) was low, irrespective of lamb birth weight. The average daily gain over the 8-week postnatal period was 86.5 g/d on restricted milk allowance compared with 244 g/d for those fed ad lib. Conversely, the food intake and growth rate of these lambs were almost identical during feeding on ad lib. concentrates. This clearly reflected a response to compensatory food intake which was independent of either birth weight or postnatal milk allowance. The average daily gain of lambs, before weaning, on the restricted milk allowance was very similar to that of the lambs being suckled by ewes subjected to perinatal undernutrition. The effects of postnatal undernutrition of lambs was particularly reflected in the time required to reach ‘slaughter’ live weight. The period of time varied from 117 d for those on ad lib. food intake to 169 d for lambs on restricted food intake.6. The major effect of postnatal undernutrition on carcass composition was evident in the lambs slaughtered at 8 weeks in Expt 1. The percentage carcass fat was 4.7 for those on the low milk allowance. The carcass composition of all lambs at ‘slaughter’ live weight was similar. It would appear that lambs on a restricted milk intake before weaning deposited more fat during the subsequent period of compensatory food intake.7. It is evident from the present results that postnatal growth retardation in lambs reflects either perinatal undernutrition of twin-bearing ewes, or postnatal undernutrition of the lambs due to inadequate milk availability from the dam.


Sign in / Sign up

Export Citation Format

Share Document