Body composition of young sheep: II. Effect of stocking rate on body composition of Dorset Horn cross lambs

1969 ◽  
Vol 72 (1) ◽  
pp. 77-84 ◽  
Author(s):  
G. W. Arnold ◽  
H. R. Gharaybeh ◽  
M. L. Dudzinski ◽  
W. R. McManus ◽  
A. Axelsen

SUMMARYEmpty body weight and body measurements were made on 142 lambs from Border Leicester × Merino and Merino ewes mated to Dorset Horn rams, grazed at three stocking rates and slaughtered at approximately 32·3 kg full body weight (FBW). Carcass composition studies were made on 58 of these lambs. An approximate doubling of growth rate during the first 6 weeks of life occurred between stocking rates for lambs from Merino ewes. A smaller difference was found in lambs from Border Leicester × Merino ewes. Growth rates of lambs from Merinos were significantly lower at all times from birth to slaughter. Stocking rate, breed and sex effects on growth rate resulted in lambs reaching mean weight of 32·3 kg at 80–150 days.A three-way analysis of variance was performed on data for all parameters measured using FBW as a covariate. These parameters were of carcass measurements and composition, and of composition of the internal organs. There were no effects of stocking rate on empty body weight, carcass weight, or any carcass measurements. The weight of dry edible meat was depressed at the high stocking rate due to a higher moisture content. The fresh weight of internal organs was lower at the high stocking rate. A number of sex differences were found. Ewes had lighter carcasses and heavier cannon bones; their edible meat had a higher moisture content and higher ash content than wethers. Eye muscle width was less in ewes than in wethers. Internal organs of ewes had a lower EE % and higher CP % than those of wethers. The only breed type differences were in the weights of internal organs and eye muscle widths at the 9–10th and lOth–llth ribs, and age to slaughter.

1974 ◽  
Vol 52 (4) ◽  
pp. 447-456 ◽  
Author(s):  
A. J. Niimi ◽  
F. W. H. Beamish

Changes in growth and proximate body composition of largemouth bass (Micropterus salmoides) were examined for fish of 8–150 g, between 18 and 30C. For most weights, growth of fish (grams/day) was highest at 25C, and lowest in fish at 18C. This was attributable in part to a higher satiation (maximum) feeding level at 25C. For a fixed level of feeding, growth rate (percentage wet weight/day) was highest for fish held at 18C.Lipid content (percentage wet weight) increased with feeding level and was highest at 18C, Moisture content varied inversely with lipid. Protein and ash content did not vary appreciably with temperature, body weight, or feeding level.Maintenance requirement of bass, expressed as grams/day, was about twice that lost during food deprivation, but only slightly different when expressed as kilocalories/day.Energy requirements for nonfecal losses were estimated as 10% of intake energy at all feeding levels. Standard metabolism accounted for 50% of intake energy near maintenance, but only 10% at the satiation feeding level. Growth requirements increased From zero at maintenance to 40% of intake energy at satiation feeding.


1964 ◽  
Vol 6 (3) ◽  
pp. 309-319 ◽  
Author(s):  
S. K. Stephenson

1. Body shape and carcass composition have been measured in a dated series of Romney-Southdown cross and Australian Merino sheep foetuses.2. Large differences in shape exist between the two breed groups and these result from growth rate differences in certain components of the bone and muscle tissue.3. Carcass composition at any particular foetal weight, however, is more uniform. In relation to body weight, the Merino has a higher proportion of bone in the body but the proportion of muscle is the same in both breed groups. Nevertheless, the distribution of muscle tissue is changed as there s i a higher proportion of muscle in the hind limb of the Romney-Southdown cross.


1976 ◽  
Vol 87 (3) ◽  
pp. 605-616 ◽  
Author(s):  
J. E. Newton ◽  
N. E. Young ◽  
R. J. Orr

SummaryA comparison was made between an intensive system of lamb production based on Italian ryegrass RvP and one based on perennial ryegrass S. 24, over 2 years, each at three stocking rates (14, 17, 20 ewes/ha). More grass was grown in the first year than in the second when the yield of RvP was particularly reduced. The ewes and lambs ate more RvP than S. 24 but there was no difference in lamb growth rate. The lambs grew faster at the low stocking rate from 0 to 18 weeks and from 0 to slaughter than at the medium and high stocking rates, in both years. Ewe intake and lamb growth rate were higher in the second year than the first. The Masham ewes with two lambs ate significantly more grass per unit of body weight than the Finnish Landrace × Scottish Halfbred and Finnish Landrace × Scottish Blackface ewes, and their lambs grew significantly faster. It was concluded that for an intensive system of lamb production from grass, S. 24 was more suitable than RvP.


1984 ◽  
Vol 39 (2) ◽  
pp. 177-193 ◽  
Author(s):  
R. M. Seebeck

ABSTRACTComparative slaughter was used to assess the body composition of Shorthorn-Hereford (SH), Africander cross (A×), Brahman cross (B×), and late castrated Brahman cross (B×(late)) steers of the F, generation with respect to their yield of carcass, gross carcass composition and offal composition. Animals were slaughtered at pre-determined weights of 315, 355, 399, 449 and 505 kg.The B× animals had the highest carcass yield (expressed either as dressed carcass weight at the same fasted body weight or at the same empty body weight), while the A×, B×(late) and SH animals had similar carcass yield. Within a breed, rate of growth affected carcass yield, with faster growing animals having the lower carcass yield, particularly with respect to fasted body weight.The breeds were different in carcass composition but this was dependent on both size and growth rate. Brahman cross animals had a lower proportion of bone than A× and SH animals, particularly at the higher body weights. Faster growing animals tended to contain more muscle and bone and less fat, with the exception of the SH animals.The breeds were also significantly different in the composition of the offal components. A× were notable for high head weights and low tail weights, B× having high blood weights and low total gut tissue weights, and Bx(late) having high hide weights and low abdominal fat weights.Rate of growth had some effect on offal composition, the general trend being that the faster growing animals were characterized by a lower proportion of heart, blood and pancreas. However there was also evidence that the rate of growth differentially affected the offal composition with respect to breeds. This effect mainly arose because the faster growing B×(late) animals had lower weights of abdominal fat. Within the other breeds, the opposite trend was observed.


Author(s):  
M Wan Zahari ◽  
J K Thompson ◽  
D Scott

The effects of plane of nutrition on the body composition of growing sheep are very apparent when animals are compared at the same age following different nutritional histories. These differences are, however, less obvious when animals of the same breed and sex are compared at the same body weight and at present there is some conjecture whether composition is affected by growth rate. This uncertainty is not limited to fat and protein but includes the bone and ash, fraction and the ash composition.The primary objective of this trial was to study the effects of different growth rates achieved by feeding different amounts of the same concentrate diet on the composition of empty-body gain and on the retention of minerals by growing lambs. A secondary objective was to examine the effect of adding supplementary calcium carbonate to the basal diet at the fast rate of growth.


Animals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 963 ◽  
Author(s):  
Dariusz Kokoszyński ◽  
Rafał Wasilewski ◽  
Mohamed Saleh ◽  
Dariusz Piwczyński ◽  
Henrieta Arpášová ◽  
...  

Native breeds of ducks have been the subject of many studies in the past, yet the relevant knowledge is still incomplete and needs to be further expanded. The objective of this study was to provide information about differences in growth performance, dressing percentage, carcass composition and digestive morphometry among three lines of Pekin ducks from conservation flocks raised in Poland. The study used 180 sexed Pekin ducks—30 males and 30 females of line P33 (ducks of Polish origin), 30 males and 30 females of line P8 (ducks of Danish origin), and 30 males and 30 females of line P9 (ducks of French origin). Throughout the study (49 d), ducks were confined indoors in six pens. Birds were fed complete commercial diets ad libitum and had unrestricted access to water. The compared lines of ducks differed significantly in body weight from 1 to 49 d of age except of ducks of both sexes at 14 d. At 49 d of age, significant differences were observed between the tested ducks in all the body measurements. Duck genotype had a significant effect on preslaughter body weight, carcass weight and breast muscle, neck and remainders contents, caeca length, liver weight and gizzard percentage. The results show that the tested ducks were significantly different and unique, mainly in terms of the body biometric characteristics.


1974 ◽  
Vol 18 (2) ◽  
pp. 191-199 ◽  
Author(s):  
J. E. Newton ◽  
N. E. Young

SUMMARYTwo forms of supplement, barley or dried grass pellets (G) were given to weaned lambs, set-stocked at pasture, at three stocking rates (43·5, 60 and 87 per hectare). The supplements were given either from weaning or from the time growth rate fell below a target value. The supplements significantly increased the proportion of lambs reaching the target weight (35 kg) and G was significantly better than barley, but slightly more G was given. The substitution value of supplement for herbage was 0·48 ± 0·12 and there was no difference in this value between barley and G. The proportion of lambs reaching the target slaughter weight was not influenced by whether the supplement was offered at weaning or delayed until lamb growth declined below a target level. Increase in stocking rate depressed the herbage intake and growth rate of the unsupplemented control lambs.


1969 ◽  
Vol 72 (1) ◽  
pp. 65-75 ◽  
Author(s):  
H. R. Gharaybeh ◽  
W. R. McManus ◽  
G. W. Arnold ◽  
M. L. Dudzinski

SUMMARYFlocks of 9-month-old Merino and Border Leicester & Merino sheep were sampled over the full range of body weights present within flocks. Six pairs of ewes and wethers of equal body weight were taken. The sheep were weighed and slaughtered after a 36 h fast. Total weights of blood, skin, head, feet, internal organs and carcasses were obtained for each animal. Each component was analysed for ash, crude protein, ether extract and total energy. Half of each carcass was dissected into bone, muscle, fat and waste.The compositions of the sheep were compared by regression analyses of weights of body components on empty body weight (EBW) between the four groups and by means of percentages of EBW. There were highly significant linear relationships between both fresh and dry weights of body components, carcass components, and chemical components with EBW; moisture content was not related to EBW. Rates of change with EBW in weights of body components, or in amounts of ash, crude protein, ether extract and energy were the same for all groups of sheep with the exceptions of bone and skin ether extract (EE) weight. However, intercepts of regression lines frequently differed, indicating that body composition differed between groups at the same EBW.All groups had the same dry weight of blood, internal organs and muscle, weight of ether extract, and total energy in the whole body at the same EBW. Border Leicester × Merinos had lighter skins with less wool, but their carcass weights were higher than Merinos. There were other differences between breeds in the chemical composition of individual components. Wethers had heavier head + feet weights and carcass bone than had ewes. There were also some sex differences in chemical composition of body components. In general, there were fewer sex than breed differences in body composition. The breed differences cannot be explained on the basis of early and later maturing types.


1976 ◽  
Vol 16 (83) ◽  
pp. 810 ◽  
Author(s):  
BD Hill ◽  
DG Saville

A grazing experiment was conducted at Cowra, on the western slopes of New South Wales, on a pasture consisting of lucerne (Medicago sativa) and annual species including capeweed (Arctotheca calendula), barley grass (Hordeum leporinum). wimmera ryegrass (Lolium rigidum) and subterranean clover (Trifolium subterraneum) . The performance of Border Leicesterx Merino ewes mated to Dorset Horn rams and the growth of their progeny was compared under rotational and set stocked grazing management systems, with and without a 20 per cent area of lucerne saved for grazing when additional feed was required. There was one stocking rate (8.7 ewes ha-1) in 1966 and two (8.7 ewes ha-1 and 13.0 ewes ha-1) in 1967 to 1969. Rotational grazing decreased the lamb growth rate but increased the number of lambs born. The management system did not affect the body weight or wool production of the ewes. Lucerne was quickly eliminated from the set stocked areas and was greatly reduced in the rotational systems. Capeweed became dominant in the set stocked areas. Saving increased the number of lambs born at the high stocking rate in 1967 to 1969. In 1966 saving reduced lamb growth, ewe body weight and wool growth in the rotational system. The high stocking rate increased wool production per hectare, but decreased the number of lambs born and, in 1967, the lamb growth rate.


1955 ◽  
Vol 12 (2) ◽  
pp. 210-237 ◽  
Author(s):  
M. W. Smith

A significantly faster growth rate by native and planted eastern brook trout followed the addition of commercial fertilizers in sufficient quantities to provide potential additional concentrations of 0.39 mg. P, 0.21 mg. N and 0.27 mg. K per litre in Crecy Lake (20.4 ha.; mean depth, 2.4), New Brunswick. Largely because trout planted as fingerlings attained suitable angling size when yearlings, the rate of capture and the yield by weight to anglers approximately doubled. The improved growth rate, but not yields, persisted into the second and third years after fertilization. Coincident was an increase in predation by fish-eating birds and mammals. With predator control and the same stocking rates, the yield of trout flesh produced in the lake increased from 0.9 to 5.9 kgm. per hectare over the next two-year period. With predator control extended to trapping eels in the lake, a second comparable fertilization with respect to concentrations of P, N and K, and a doubling of the stocking rate, a yield of 9.7 kgm. per hectare was realized. The growth rate was somewhat depressed with the heavier stocking, notwithstanding a second fertilization. Facilities for natural reproduction were poor and planted trout (fingerlings and yearlings) sustained the fishery. Maximum survivals of planted trout (all marked) to anglers' catches were 20 per cent for fingerlings and 88 per cent for yearlings. Cropping of trout of age II was thorough. For the most part, movements of planted trout (trapped in outlet) from the lake would have occasioned minor losses.Neighbouring Gibson Lake (24.0 ha.; mean depth, 4.0 m.) was fertilized with one-half of the concentrations of P, N and K applied to Crecy. Stocking with trout was at comparable rates but no predator control was exercised. Little improvement was noted in the growth of the trout. Only when yearlings were planted late in the fall and angled early in the spring was there any improvement in the anglers' catches.


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