Efficiency of growth and wool production of young Merino ewes from a flock selected for fertility

1976 ◽  
Vol 16 (80) ◽  
pp. 315 ◽  
Author(s):  
KD Atkins ◽  
GE Robards
Keyword(s):  
Growth Rate ◽  
Organic Matter ◽  
Reproductive Rate ◽  
Feed Conversion ◽  
Or Efficiency ◽  
Net Reproductive Rate ◽  
Wool Production ◽  
Significant Difference ◽  
Digestible Organic Matter ◽  
Conversion Efficiencies

A handfeeding experiment was conducted with weaner ewe lambs from two Merino flocks. One flock had been selected for high net reproductive rate, growth rate and wool production (fertility flock) ; the other flock was a randomly selected control flock (random flock). Single and twin born lambs from each flock were used in the experiment. Lambs were randomized into four treatment groups and offered the diet either ad libitum or at one of three levels estimated to restrict growth rate to 50, 100 and 150 g day-1. At each level of feeding, fertility flock lambs grew faster and were more efficient in converting feed to liveweight gain. Over the whole experiment the feed conversion efficiencies in g gain per kg digestible organic matter intake per day were 218 and 185 (P < 0.05) for the fertility and random flocks respectively. There were no significant differences in growth rate or efficiency of conversion of feed to liveweight gain between single-born and twin-born lambs. Random flock lambs had a significantly higher wool growth rate and were more efficient converters of feed to wool than fertility flock lambs. Gross efficiencies were 10.8 and 9.1 g clean wool per kg digestible organic matter intake per day (P < 0.05) for random and fertility flock lambs respectively. Single-born lambs grew significantly more wool than twin-born lambs but there was no significant difference between birth types in the efficiency of conversion of feed to wool.

The effect of time of weaning on the biological efficiency of meat production in sheep

1975 ◽  
Vol 20 (2) ◽  
pp. 233-241 ◽  
Author(s):  
J. M. Walsingham ◽  
R. V. Large ◽  
J. E. Newton
Keyword(s):  
Growth Rate ◽  
Organic Matter ◽  
Post Partum ◽  
Biological Efficiency ◽  
Meat Production ◽  
Digestible Organic Matter ◽  
Breed Crosses

SummaryThe value of E, defined as the weight of carcass produced per 100 units of digestible organic matter (DOM) consumed, was used to assess the biological efficiency of meat production in housed sheep. The effect on E of weaning lambs at 4, 6, 8, 10, 12, 14 and 16 weeks post partum was studied for a number of different breed crosses. The age at which lambs were weaned was found to have little effect on the growth rate of lambs and no significant effect on the biological efficiency with which sheep produce meat.

Stimulation of wool growth by thyroxine implantation. II. Feed intake of grazing Merino wethers treated repeatedly with thyroxine.

1964 ◽  
Vol 15 (4) ◽  
pp. 676 ◽  
Author(s):  
LJ Lambourne
Keyword(s):  
Organic Matter ◽  
Feed Intake ◽  
Sheep Grazing ◽  
Wool Production ◽  
Wool Growth ◽  
Digestible Organic Matter ◽  
The Difference ◽  
Maintenance Requirements ◽  
Substantial Rise ◽  
Stimulation Of

Estimates have been made of the feed intake of wethers that received implantations of 60 mg thyroxine every 3 months, and of untreated sheep, grazing together. The estimated intake of digestible organic matter (D.O.M.) by treated wethers was higher than that of controls in 24 out of 27 measurement periods. The difference in feed intake was least in the iirst month after implantation, when the treated sheep lost weight, and greatest in the second and third months when the treated sheep were regaining weight. The overall increase in intake resulting from thyroxine treatment (20–25%) was greater than the increase in wool production (7% greasy weight, 3-7 % clean weight), and the efficiency of wool production was therefore lower in thyroxinetreated wethers. From the relationships between feed intake and rate of weight change it was concluded that in the month after implantation, when pulse rates indicated a substantial rise in metabolic rate, the maintenance feed requirement was raised from about 560 g to about 780 g D.O.M. per day. Observations in two winters with recently shorn sheep gave estimates of maintenance requirements for untreated wethers ranging from 850 to 1300 g D.O.M. per day. During recovery from repeated thyroxine implantation the wethers gained in weight no more efficiently than the controls. The mechanism of action of exogenous thyroxine is discussed in the light of these and other data.

scholarly journals The intake, digestion and protein degradation of grazed herbage by early-weaned lambs

1992 ◽  
Vol 68 (2) ◽  
pp. 349-364 ◽  
Author(s):  
G. J. Cruickshank ◽  
D. P. Poppi ◽  
A. R. Sykes
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Organic Matter ◽  
Species Difference ◽  
Similar Rate ◽  
Ammonia Nitrogen ◽  
Grass Species ◽  
Pure Species ◽  
Prairie Grass ◽  
Digestible Organic Matter

Sixty-four intact lambs and twenty-four lambs fitted with a duodenal cannula were weaned at 6 weeks of age and grazed pure species swards of either lucerne (Medicago sativa), white clover (Trifolium repens), ryegrass (Lolium perenne) or prairie grass (Bromus catharticus) for 6 weeks. Intake and duodenal digesta flow were estimated when lambs were 8 and 12 weeks of age. Lambs grazing the two legume species grew at a similar rate, as did lambs grazing the two grass species. Legumes promoted a 38% higher growth rate than grasses. The higher growth rate of lambs grazing legumes was associated with a 36% higher digestible organic matter intake (DOMI; 29.5 and 21.7 g/kg body-weight per d for legume and grass respectively) and a 33% higher duodenal non-ammonia-nitrogen (NAN) flow (1.22 and 0.92 g/kg body-weight per d respectively). There was no species difference in the site of organic matter digestion; on average 0.56 of DOMI was apparently digested in the rumen and 0.77 of DOMI was truly digested in the rumen. There was no difference in duodenal NAN flow, relative to DOMI (average, 43 g/kg) or to organic matter apparently digested in the rumen (80 g/kg). Similarly, there was no difference in microbial N flow relative to duodenal NAN (0.50 g/g) and organic matter apparently (41 g/kg) or truly (29 g/kg) digested in the rumen. It was concluded that the higher growth rates achieved by lambs grazing legumes were due to higher intakes which increased the total quantity of nutrients supplied despite more protein being lost in the rumen of lambs consuming legumes.

The response of Merino lambs given whole wheat supplemented with urea or hay

1985 ◽  
Vol 25 (1) ◽  
pp. 32 ◽  
Author(s):  
RW Hodge ◽  
C Kat
Keyword(s):  
Organic Matter ◽  
Dry Matter ◽  
Nitrogen Retention ◽  
Dry Matter Intake ◽  
Whole Wheat ◽  
Significant Difference ◽  
Digestible Organic Matter

There was no significant difference in digestible dry matter intake (6 14 v. 63 1 g/day), liveweight gain (1 33 v. 13 1 g/day) or nitrogen retention (9.6 v. 11.2 g N/kg digestible organic matter) of Merino lambs offered whole wheat or whole wheat supplemented with 1.5% urea. Supplementation of the wheat or wheat plus urea rations with 20% hay also had no significant effect on total dry matter intake or liveweight gain.

scholarly journals The Effect of Ploidy on Growth and Feeding Pattern of Diploid and Triploid Turbot Scophthalmus maximus Under Communal Rearing Condition

2021 ◽  
Vol 21 (06) ◽  
pp. 275-281
Author(s):  
Ilhan Aydin
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Scophthalmus Maximus ◽  
Average Weight ◽  
Feed Conversion ◽  
Farmed Fish ◽  
Conversion Rates ◽  
Significant Difference ◽  
Turbot Scophthalmus Maximus

Triploidy induction is a useful tool to produce sterile fish that prevents interbreeding of farmed fish with wild counterparts. In this study, growth performance and feed conversion rates of 12-months old diploid and triploid turbot that reared both communally and separately for 16 months at constant water temperature determined. At the end of the experiment, diploid, triploid, and communally reared groups reached an average weight of 672.4±21.0 g, 659.2±25.3 g and 660.5±12.0 g, respectively. Any significant differences were not observed in the weight of separately reared diploid and triploid turbot groups. In contrast, triploid fish in the communal group were significantly heavier than diploids at the end of the rearing period. The feed conversion rate of the ploidy group did not show any significant difference between groups. The highest mean specific growth rate was observed in the triploids in communal groups, whereas the diploids in communal groups had the lowest mean specific growth rate. The weight and length gain rates of the groups were similar. Diploid turbot growth appeared to be negatively affected by communal ploidy rearing. The results of the present study indicate that triploid turbot farm escapees may be advantageous in terms of growth in nature.

Studies in the wool production of grazing sheep. 4. Variation between sheep in intake, wool production, and efficiency

1966 ◽  
Vol 6 (20) ◽  
pp. 96 ◽  
Author(s):  
WR McManus ◽  
GW Arnold ◽  
ML Dudzinski
Keyword(s):  
Organic Matter ◽  
Wool Production ◽  
Digestible Organic Matter ◽  
Grazing Sheep ◽  
Stocking Rates

The results of a three-year experiment with Merino wethers grazed at four stocking rates were examined. There were consistent differences between individual sheep at all times of the year in their intake of digestible organic matter (DOMI), clean wool production (WP), and in their efficiency of conversion of food to wool (E). Within stocking rates there were no consistent relationships between DOMI and WP.

The food conversion efficiency in lambs of two crosses of sheep

1967 ◽  
Vol 7 (26) ◽  
pp. 199 ◽  
Author(s):  
ME Bourke
Keyword(s):  
Growth Rate ◽  
Organic Matter ◽  
Conversion Efficiency ◽  
Animal Tissue ◽  
Food Conversion ◽  
Factors Associated ◽  
Digestible Organic Matter ◽  
High Level ◽  
Food Conversion Efficiency

The experiment investigated factors associated with differences in growth rate from birth to seven weeks, by two crossbreeds of lamb. The Dorset Horn x Border Leicester-Merino grew at 0.18 kg per day, and the Dorset Horn x Merino grew at 0.14 kg per day (P<0.001) although both crosses consumed the same digestible organic matter intake. Thus the second cross was significantly more efficient (P<0.05) than the first cross. Two levels of milk were also fed to both crosses and, although the high level improved growth rate (P <0.001), it did not effect the efficiency of conversion of food to animal tissue.

scholarly journals Consequences of prenatal and preweaning growth for feedlot growth, intake and efficiency of Piedmontese- and Wagyu-sired cattle

2009 ◽  
Vol 49 (6) ◽  
pp. 461 ◽  
Author(s):  
L. M. Cafe ◽  
D. W. Hennessy ◽  
H. Hearnshaw ◽  
S. G. Morris ◽  
P. L. Greenwood
Keyword(s):  
Growth Rate ◽  
Feed Intake ◽  
Early Life ◽  
Dry Matter ◽  
Low Birthweight ◽  
Conversion Ratio ◽  
Feed Conversion Ratio ◽  
Long Term Effects ◽  
Feed Conversion ◽  
Or Efficiency

Consequences of low (mean 28.0 kg, n = 77) and high (mean 38.4 kg, n = 77) birthweight followed by slow (mean 548 g/day, n = 75) or rapid (mean 859 g/day, n = 79) growth to weaning for feedlot growth, intake and efficiency from 26 to 30 months of age were determined in Wagyu × Hereford (n = 81) and Piedmontese × Hereford (n = 73) cattle. Cattle were selected for study based on birthweight and preweaning growth rate, from multi-modal distributions achieved by imposition of low or high maternal nutrition during pregnancy and lactation, with the objective of achieving as close as possible to a 30% difference in birthweight and a 2-fold difference in preweaning growth rate between progeny groups. High birthweight cattle entered the intake test 57 kg heavier, grew 100 g/day more rapidly, and ate 1.0 kg dry matter /day more than the low birthweight cattle. The high birthweight cattle tended to have a higher feed conversion ratio than low birthweight cattle, but net feed intake did not differ due to birthweight group. Cattle grown rapidly to weaning entered the intake test 29 kg heavier, grew at an equivalent rate, and ate 0.7 kg dry matter/day more than the cattle grown slowly to weaning. No differences in feed conversion ratio or net feed intake were observed between the preweaning groups. When assessed at the same liveweight, differences in dry matter intake and/or feed conversion ratio due to birthweight or preweaning growth were no longer apparent. Interactions between prenatal and preweaning growth, or between sire genotype and early-life growth, were not evident for feedlot growth, intake or efficiency. It is concluded that severely restricted growth during prenatal life or from birth to weaning results in cattle that are smaller and consume less feed at the same age as their well grown counterparts; however, long-term effects of growth during early life on efficiency of utilisation of feed are not evident.

The effect of herbage allowance on herbage intake and performance of lambs grazing perennial ryegrass and red clover swards

1976 ◽  
Vol 86 (2) ◽  
pp. 355-365 ◽  
Author(s):  
M. J. Gibb ◽  
T. T. Treacher
Keyword(s):  
Growth Rate ◽  
Organic Matter ◽  
Perennial Ryegrass ◽  
Nitrogen Fertilizer ◽  
Daily Intake ◽  
Live Weight ◽  
Red Clover ◽  
Asymptotic Curves ◽  
Digestible Organic Matter ◽  
The Relationship

SummaryThe effect of daily herbage allowance on herbage intakes and growth rates lambs grazing perennial ryegrass and red clover was investigated in two experiments. Herbage allowances defined as g herbage D.M./kg live weight (LW)/day were controlled by varying the areas of plots grazed for 2 days by groups of six lambs.In the first experiment five herbage allowances in the range 20–120 g D.M./kg LW/day were offered on two areas of a perennial ryegrass (cv. S. 23) sward that received nitrogen fertilizer applications of 39 or 78 kg N/ha/28 days. In the second experiment five herbage allowances in the range 30–160 g D.M./kg LW/day were offered on perennial ryegrass (cv. S. 23) and red clover (cv. Hungaropoly) swards.Asymptotic curves were fitted to describe the relationship between herbage allowance and daily intake of herbage. In Expt 1 nitrogen fertilizer rates did not affect the yield of herbage or animal performance. In Expt 2 intakes were higher on the clover sward than on the ryegrass sward at the higher herbage allowances.The asymptotic curves to describe the relationship between herbage allowance and growth rate of lambs differed widely between periods. Growth rate of the lambs increased linearly with increase in digestible organic matter intake. Live-weight gain per unit of digestible organic matter intake was higher on the red clover than on the ryegrass.The conclusion is drawn that if the herbage present to ground level is not more than three times the daily intake of the animals, intake of herbage of the animals may bo restricted.

Effect of degradability of protein supplements on voluntary intake and nitrogen retention in young cattle fed grass silage

1984 ◽  
Vol 39 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Margaret Gill ◽  
P. England
Keyword(s):  
Organic Matter ◽  
Dry Matter ◽  
Latin Square ◽  
Nitrogen Retention ◽  
Protein Supplementation ◽  
Protein Supplements ◽  
Grass Silage ◽  
Significant Difference ◽  
Digestible Organic Matter ◽  
Gross Energy

ABSTRACTGrass silage was offered ad libitum to twelve 4-month-old British Friesian steers in an incomplete Latin-square experiment. The silage was given either alone or supplemented isonitrogenously with 50 g fish meal or 63 g groundnut meal per kg silage dry matter.Both protein supplements significantly increased the intakes of dry matter and organic matter by an amount about equivalent to the (calculated) contribution of the supplement (P < 0·05); they also increased the intakes of digestible organic matter and nitrogen (P < 0·001) but with no significant difference between supplements. Protein supplementation had no effect on the intake of indigestible organic matter.The digestibility coefficients of dry matter and of organic matter were significantly increased by supplementation (P < 0·05) as were the digestibility coefficients of gross energy and of nitrogen (P < 0·001). Nitrogen retention was also increased from 1·4 to 8·2 g/day (P < 0·001), with no significant difference between supplements.

Sign in / Sign up

Export Citation Format

Share Document