The growth and development of nine European sheep breeds. 1. British breeds: Scottish Blackface, Welsh Mountain and Shetland

1997 ◽  
Vol 65 (3) ◽  
pp. 409-426 ◽  
Author(s):  
N. C. Friggens ◽  
M. Shanks ◽  
I. Kyriazakis ◽  
J. D. Oldham ◽  
T. H. McClelland

AbstractThe objective of this study was to assess the growth and development of carcass composition of entire male and female lambs of three British hill breeds (Scottish Blackface, Welsh Mountain, and Shetland), from weaning to approaching maturity, when kept under conditions designed to be nutritionally non-limiting. Lambs were weaned at 8 weeks of age and given a high-quality pelleted diet ad libitum until slaughter at one offive different degrees of maturity. The Gompertz growth function was used to characterize, for each genotype, the growth curve and to provide estimates of mature weight. As expected, there were significant effects of breed and sex on both food intake and growth rate. Growth rate was depressed, relative to the Gompertz fit, during the months of October to January, and intake was similarly depressed. The estimates of mature weight for the females of each breed were: Scottish Blackface, 69; Welsh Mountain, 61; Shetland, 46 kg. The mature weights of the males were found to be not significantly different from 1-3 times the mature weight offemales. Relationships between carcass composition and live weight were derived by allometric regression. This study provides the first full description of the growth and meat production potential of the three breeds.

1997 ◽  
Vol 65 (3) ◽  
pp. 427-440 ◽  
Author(s):  
D. Zygoyiannis ◽  
I. Kyriazakis ◽  
C. Stamataris ◽  
N. C. Friggens ◽  
N. Katsaounis

AbstractThe objective of this study was to assess the growth and development of carcass composition of entire male and female lambs of three Greek dairy breeds (Boutsko, Serres and Karagouniko), from weaning to live weights approaching maturity, when kept under conditions designed to be nutritionally non-limiting. Lambs were weaned at 6 weeks of age and given a high quality pelleted food ad libitum until slaughter at one offive different degrees of maturity. As expected, there were significant effects of breed and sex on both food intake and growth rate. The Gompertz growth function was used to characterize, for each genotype, the growth curve and to provide estimates of mature weight and appeared to describe adequately growth rate. For two breeds (Serres and Karagouniko) food intake (g/day) increased in a linear fashion with time up to approximately 24 weeks of age and then remained static for the last 10 to 22 weeks of the experiment; this coincided with the increased environmental temperatures during summer. No such plateau in food intake was seen for the Boutsko sheep. The estimates of mature weight (kg) for the females of each breed were: Boutsko, 60; Serres, 66; Karagouniko, 77. These were substantially in excess (1·4 times on average) of the pre-trial calculations of mature weight. The mature weights of the males were found to be not significantly different from 1·3 times the mature weights of the females. Relationships between carcass composition and weight were derived by allometric regressions. This study provides the first full description of the growth and meat production potential of the three Greek breeds; as such it is part of an overall study that aimed to characterize (for thefirst time as far as the authors are aware) nine sheep breeds from diverse regions of the European Union.


1980 ◽  
Vol 95 (2) ◽  
pp. 251-259 ◽  
Author(s):  
A. S. Davies ◽  
G. Pearson ◽  
J. R. Carr

SUMMARYAn anatomical study compared the effects of sex and a twofold nutritional difference in growth rate between 20 and 100 kg live weight, on 63 entire males, castrated male and female Large White × Landrace pigs. While the effect of growth rate was significant for overall fat deposition in the carcasses of all three sexes, it was greatest for the entire male. In contrast, sex and nutritional effects on the distribution of fat and on the proportion and distribution of muscle and bone were small.


1984 ◽  
Vol 39 (1) ◽  
pp. 107-114 ◽  
Author(s):  
B. W. Butler-Hogg ◽  
M. A. Francombe ◽  
E. Dransfield

ABSTRACTCarcass composition and quality and eating quality of the m. longissimus dorsi (LD) were compared in 15 entire male (ram) and 15 female (ewe) pure bred Dorset Down lambs (carcass weight range 12 to 23 kg).Rams grew 28 g/day faster than ewes, taking on average 2 weeks less to achieve 35 kg live weight. At the mean carcass weight of 16-8 kg, ram carcasses contained more lean (42 g/kg carcass weight) and bone (19 g/kg) and less fat (subcutaneous, 33 g/kg; intermuscular, 28 g/kg; perirenal-retroperitoneal, 14 g/kg) than ewe carcasses.At the same level of fat cover in the commercially prepared side, ewe carcasses required more trimming of subcutaneous fat than rams. However, there was more intermuscular fat (which is not removed by conventional cutting) in the ewes; consequently their saleable meat contained 51 g/kg more fat and 37 g/kg less lean than that from rams.The roast LD was invariably tender and the eating quality of LD from rams was as desirable as that from ewes, while overall eating quality compared favourably with that of animals studied previously. There was no evidence of an undesirable sexual odour or flavour in ram meat.With early maturing breeds, which can be finished off grass, non-castration of entire males offers the opportunity of improving the efficiency of lean meat production whilst retaining good carcass and eating quality.


2008 ◽  
Vol 51 (6) ◽  
pp. 549-559 ◽  
Author(s):  
D. Jordan ◽  
S. Žgur ◽  
G. Gorjanc ◽  
I. Štuhec

Abstract. Fattening pigs are commonly kept in intensive housing systems with slatted floor which represent a very barren environment, causing poor animal welfare. To improve such conditions a small amount of straw or hay (100 g per animal per day laid daily in a rack) was used in our study as an environmental enrichment (EE). Two replications, each including 96 fattening pigs of both sexes (3 pens of 16 females and 3 pens of 16 male castrates) from 60 kg to slaughter at average 96 kg live weight, were used to test the effect of EE and sex on behaviour, growth rate, and carcass composition. EE significantly increased the proportion of total activity during the illumination period (between 6 a. m. and 2 p. m.) on account of increased occupation with substrate (P<0.01). EE also significantly reduced time spent biting pen bars and frequency of aggressive encounters (P<0.01). The EE increased total activity in female animals during the observation period, but not in male castrates. None of the EE significantly influenced pigs‘ growth rate and lean meat percentage; however females in enriched environment grew slower and had greater lean meat percentage than the castrated males. Provision of a small amount of straw or hay to pigs in intensive housing systems can enrich barren environment in inexpensive and efficient way. Therefore such enrichment can be widely used also in large commercial pig production systems.


Author(s):  
J.D. Wood ◽  
G.R. Nute

There is anecdotal evidence that the meat of wild pigs is particularly tasty and their carcasses are lean. However it may be that the nature of the wild existence - high energy demands, low energy diet, unusual ingredients eg acorns and plant roots - is important in conferring these qualities. This Study was done to determine whether semi-wild pigs - the so called “Iron Age” breed - are different from typical modern white pigs (Large Whites) when both are reared on ‘modern’ commercial diets. Tests on carcass composition and meat quality were therefore made.“Iron Age” pigs (IAP) were formed at the Cotswold Farm Park by crossing the European Wild Pig with the Tamworth. Three litters were obtained from 2 sires and 1 female and the progeny reared from about 20 kg on a pelleted diet (13.0 MJDE/kg) fed ad libitum. Slaughter was at approximately 60 kg live weight for the 18 IAP and 6 Large White (LW) pigs (balanced for sex) used in the tasting tests and between 10 and 240 kg for the dissected animals (250 LW, 19 IAP) - these data were then corrected to 65 kg live weight. The LW pigs were from several litters reared on the Institute farm.


1987 ◽  
Vol 45 (1) ◽  
pp. 87-96 ◽  
Author(s):  
A. C. Parratt ◽  
G. Simm

AbstractSelection indices to improve lean meat production of terminal sire breeds of sheep were derived. An aggregate breeding value which comprised growth rate, killing-out proportion and carcass lean proportion was examined. Selection criteria included growth rate and ultrasonic or X-ray computer tomography (CT) estimates of carcass composition. Correlations betwen the index and the aggregate breeding value were about 0·38 for indices using ultrasonic fat measurements, and about 0·40 for those using CT measurements. Dropping ultrasonic or CT measurements from the indices reduced the correlations with the aggregate breeding value by only about 0·01 and 002 respectively, indicating that selection on growth rate alone under current economic conditions was highly efficient. Changes in economic weights, and genetic parameters had little effect on the efficiency of selection. The total national discounted value of returns from a single round of selection on the indices was expected to be between £6 and £30·5 million, depending on penetration rates of improved stock, the breeding scheme used, and with a time horizon of 20 years.


1963 ◽  
Vol 61 (2) ◽  
pp. 233-241 ◽  
Author(s):  
F. W. H. Elsley

1. A comparison was made of the carcass composition at 56 days of age of early-weaned pigs grown along predetermined growth curves to 30, 40 and 50 lb. live weight and of suckled pigs grown to 50 lb. live weight at 56 days of age.Eight blocks of four pigs were slaughtered when 56 days old and comprehensive carcass dissections undertaken.2. There were no differences in the proportionate weight of the joints or of individual bones between the suckled and early-weaned pigs weighing 50 lb. at 56 days of age.The difference in the proportionate weights of the joints between the three groups of early-weaned pigs reflected the change in development which took place with increasing live weight. There was, however, no clear gradient of development along the bones of the limbs with increasing weight at 56 days of age.3. The dissected joints (hams, shoulders, neck, pelvis and loin) from the early-weaned pigs which weighed 50 lb. live weight contained 0·5% less bone, 1·5% less muscle and 1·7% more fat than the carcasses of suckled pigs reared to 50 lb. at 56 days of age.The dissected joints of the early-weaned pigs reared to 30 lb. at 56 days of age contained 1·4% more bone, 2·7% more muscle and 5·3% less fat than the joints of the early-weaned pigs reared to 40 lb. and 2·6% more bone, 5·2% more muscle and 8·8% less fat than the joints of early-weaned pigs reared to 50 lb.


1967 ◽  
Vol 9 (4) ◽  
pp. 509-520 ◽  
Author(s):  
J. B. Owen ◽  
D. A. R. Davies ◽  
E. L. Miller ◽  
W. J. Ridgman

1. Two experiments concerned with the voluntary intake of food by artificially reared lambs are described and the results discussed.2. When the diets were pelleted the addition of finely ground oat husks to form as much as 40% of the diet had practically no effect on live weight gain since the lambs controlled their consumption to achieve the same energy intake on the various diets. When the diets were given as a meal, the addition of 20% oat husks caused food intake to increase, digestible dry-matter intake to remain the same and growth rate to be somewhat poorer; but the addition of 40% oat husks caused no further increase in intake so that digestible drymatter intake fell markedly and growth rate was much reduced. It is argued that the relationship between food intake and digestibility is dependent on the physical form of the diet.3. Addition of beef tallow to the meal diets had very little effect on the lambs' performance.4. Lambs which had received a restricted quantity of milk replacer from birth to 11·4 kg live weight had a slower growth rate and poorer food conversion efficiency during the subsequent feeding period (13·6–34·1 kg) than lambs which had received milk ad libitum. This effect was greater with meal diets containing 40% oat husks than with more concentrated diets.5. On a pelleted diet containing 85% barley a conversion ratio of 3·21 was achieved over the whole fattening period, indicating the commercial feasibility of intensive lamb production on cereal diets.


1986 ◽  
Vol 43 (3) ◽  
pp. 385-390 ◽  
Author(s):  
P. C. Garnsworthy ◽  
D. J. A. Cole ◽  
M. Grantley-Smith ◽  
D. W. Jones ◽  
A. R. Peters

ABSTRACTSixty-four Friesian/Holstein cows culled from dairy herds were selected for uniformity and general health. They were allocated to five groups of 12 on the basis of body condition and live weight excluding the two cows at each extreme. These four cows indicated the range of condition and live weight in the sample and were slaughtered at the beginning of the trial with one group of 12 cows. Of the remaining four groups, two were implanted with 300 mg trenbolone acetate (Finaplix, Hoechst) and two used as unimplanted controls; one implanted group and one control group were slaughtered after 60 days and the remaining cows after 100 days. All cows were individually fed to appetite on a pelleted diet of 500 g dried lucerne and 500 g barley per kg. After slaughter the left side of each carcass was cut into primal joints and then separated into fat, lean and bone.Implantation resulted in greater live-weight gains to 60 days (1·35 v. 112 kg/day, P > 0·05) and to 100 days (1·31 v. 0·92 kg/day, P < 0·01), greater lean meat production and an increase in the lean proportion of carcasses.Feeding cows for 100 days rather than for 60 days led to higher slaughter weights but daily live-weight gain decreased and food intake increased progressively between 60 and 100 days. Carcasses from cows slaughtered at 100 days had significantly higher lean, fat and bone weights (P < 0·01) but as a proportion of side weight only the fat proportion of the carcass was significantly increased (P < 0·05).It was concluded that the supplementary feeding of cull cows produced heavier carcasses but at these high rates of gain increased yield was at the expense of proportionately more fat in the carca?.s. This problem was partially countered by implantation with trenbelone acetate.


2002 ◽  
Vol 75 (2) ◽  
pp. 185-195 ◽  
Author(s):  
R. M. Lewis ◽  
G. C. Emmans ◽  
G. Simm

AbstractSheep of a line (S) selected on an index to increase lean weight and decrease fatness at an age, and a control line (C), were given a high quality food at different levels including ad libitum. Live performance was measured from about 21 to 114 kg live weight. The carcasses of each line were analysed for lean, fat and bone at three widely varying weights in both males and females. Level of feeding did not affect the extent to which S was superior to C in either the level of fatness in the carcass (0·86 as much) or the ratio of lean to fat (1·28 as much). The lean to bone ratio was slightly greater in S (1·028 of the value of C; P 0·05) and was higher on the lowest level of feeding compared with the two higher levels used (P 0·05 in one experiment on females and P 0·001 in another on males). On ad libitum feeding the S line grew 1·19 times as fast and was 1·17 times as efficient compared with C. These advantages to S decreased as level of feeding decreased to become virtually zero at the lowest level of feeding used, which allowed C to grow at only 0·53 of the rate seen on ad libitum feeding. On ad libitum feeding growth was well described by a Gompertz growth function of the form W = (Z/B) exp(-exp (G0 –B t)). The maximum growth rate is (Z/e). Line S had a value of Z that was 1·10 that of C averaged across the two sexes. A Spillman function W = W0 + (A-W0) (1-exp (-k F)) was used to describe weight, W, in terms of cumulative intake, F. It worked well for ad libitum feeding and for the two restricted regimes used. The value of the combined parameter (A k) varied across treatments in the same way as efficiency did.


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