The growth and development of nine European sheep breeds. 2. Greek breeds: Boutsko, Serres and Karagouniko

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.

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.


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.


1999 ◽  
Vol 1999 ◽  
pp. 124-124
Author(s):  
D. Vagenas ◽  
S.C. Bishop

Dry matter food intake (DMFI) and digestibility (DIG) of the forage are two important nutritional aspects contributing to lambs growth and subsequent meat production. However, there is a lack of literature describing their inheritance and their phenotypic correlations with production traits, e.g. ultrasonic muscle and fat depth and growth rate, in the grazing lamb. This study aimed to investigate and quantify these parameters for grazing lambs.This study involved 90 male Texel-Oxford lambs in 1995 and 82 in 1996. The sires in 1996 were lambs in 1995, providing genetic links between these two generations. The lambs were split equally between two lines previously selected for increased or decreased carcass lean content. The lambs were born in a five week period in March-April each year, and they were reared on, and grazed, improved mixed- species pasture, typical of a Scottish upland farm.


1966 ◽  
Vol 17 (3) ◽  
pp. 375 ◽  
Author(s):  
ID Wardrop

The effect of the plane of nutrition in the first 13 weeks of post-natal life of cattle on their subsequent growth rate, body shape, and carcass composition up to 12 months of age was studied. No compensatory growth to 12 months of age was observed in calves reared to 13 weeks on low planes of nutrition. There were no significant differences between Friesian and Hereford x Friesian calves, or between males and females in empty body weight or weight gains. Treatment up to 13 weeks of age had no effect on heart girth, round, head length and width, and cannon bone length, but the remaining body measurements were reduced by low planes of nutrition during this period. Differences in carcass composition were largely a reflection of the differences in empty body weight. The carcasses of the males were heavier than those of the females and the females contained a higher proportion of fat. Carcass composition, as estimated by shin dissection, indicated that Friesian calves contained more muscle than the Hereford x Friesians, and the males more muscle than the females.


2003 ◽  
Vol 89 (3) ◽  
pp. 383-399 ◽  
Author(s):  
Emma C. Whittemore ◽  
Gerry C. Emmans ◽  
Ilias Kyriazakis

A model is described which aims to predict intake immediately following a change from one food to another that is higher in bulk content; it deals with the transition from one ‘equilibrium’ intake to another. The system considered is an immature pig fedad libitumon a single homogeneous food, which is balanced for nutrients and contains no toxins so that the first limiting resource is always energy. It is assumed that an animal has a desired rate of food intake (DFI) which is that needed to meet the energy requirements for protein and lipid deposition and for maintenance. DFI may not be achieved if a bulk constraint to intake exists. Where a bulk constraint operates intake is calculated as constrained food intake (CFI) where CFI=Cwhc/WHC k/ (where WHC is the water-holding capacity of the food (kg wate/g dry food) and Cwhcis the animal's capacity for WHC (unit/g live weight per d)). Where intake is not constrained it is assumed that genetic potential will be achieved. Potential growth rate is described by the Gompertz growth function. Where intake is constrained, growth will be less than the potential. Constrained growth rate is predicted as (d/t)con=(EI−Em)/egk/ where W is pig weight (kg), EI is energy intake (M/), Emis the energy required for maintenance (M/) and egis the energy required for unit gain (M/g). The value of egdepends on weight and the fattening characteristics of the pig. Actual growth is predicted to be the lesser of potential and constrained growth. To deal with adaptation it is assumed that the time taken to reach equilibrium depends on the difference in WHC values between the previous and current food and that the capacity to consume food bulk is related to the WHC of the current food. It is proposed that the capacity for WHC on the first day on a new food will be equal to the current capacity for WHC on the last day of the previous food. Thus Cwhc=(FI×WHC)/W /g, where FI is food intake (k/). Thereafter Cwhcwill gradually increase over time to a maximum of 0·27 /g. The rate of change in Cwhcis made to be the same for all pigs and all foods. The increase in capacity over time is assumed to be linear at the rate of 0·01 unit/. The model was tested using published data. Qualitatively the predictions of the model were in close agreement with the relevant observed data in at least some cases. It is concluded that the underlying theoretical assumptions of the model are reasonable. However, the model fails to predict initial intake when changed to foods high in wheat-bran content and fails to predict the intake of a non-limiting food where compensatory increases in intake and gain occur. The model could be adapted to overcome the first failure by taking into account the time course of digestive efficiency following a change in food. To deal with the second would require a sufficient understanding of the time course of compensatory growth.


1992 ◽  
Vol 54 (1) ◽  
pp. 23-30 ◽  
Author(s):  
S. C. Bishop ◽  
J. S. Broadbent ◽  
R. M. Kay ◽  
I. Rigby ◽  
A. V. Fisher

AbstractThe performance of Hereford × Friesian calves sired by Hereford bulls selected for either lean growth rate (LGR) or lean food conversion ratio (LFCR), or by unselected Hereford bulls, was evaluated on 327 calves on three farms over 2 years. Animals started test at 130 days of age on average and remained on test for approximately 300 days, whereupon all animals were slaughtered and carcass dissections were undertaken. Individual food intake was measured on tioo of the farms (189 animals), but only intake per pen of animals was measured on the third farm and individual food intake had to be estimated. LGR, LFCR and other traits describing performance were calculated from the growth, food intake and carcass composition data.If no breed or environment interactions exist it is expected that proportionately 0-5 of the genetic differences between selected and control line bulls would be transmitted to their offspring. For the LGR and LFCR line bulls these values were 0·38 and 0·44, respectively, however the LGR value had a much smaller confidence interval. Genetic correlations derived from regressing breeding values predicted from offspring performance on breeding values predicted from the bulk's own performance in the selection experiment were 0·62 (s.e. 0·28) and 0·96 (s.e. 0·28) for LGR and LFCR, respectively. Heritabilities were: live-weight gain on test, 0·27; daily gain, 0·48; food intake, 0·06; food conversion ratio, 0·46; predicted carcass lean content, 0·10; killing-out proportion, 0·10; LGR, 0·36 and LFCR, 0·48.


Author(s):  
D. Zygoyiannis ◽  
C. Stamataris ◽  
N. Katsaounis

The indigenous sheep breeds of Greece, which are used mainly for milk production, produce lambs which are killed at weaning to provide carcasses (including the head, pluck, liver, spleen and the omental and mesenteric fat) of 5 to 9 Kg. The production of heavier carcases could be of benefit if they are acceptable to consumers and if they could be economically produced. The purpose of this experiment was to characterise the growth and development of the entire males and females of three Greek breeds under conditions presumed to be non-limiting.Animals. From each of three breeds, Boutsiko (B), Serres (S) and Karagouniko (K), 20 lambs of each sex were used in a serial slaughter experiment. Four animals of each breed/sex combination were killed at live weights which were 25, 35, 50, 70 and 100% of the estimated mature values. All sheep were weaned at 6 weeks of age and the males were entire.


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.


Weed Science ◽  
1988 ◽  
Vol 36 (6) ◽  
pp. 784-786 ◽  
Author(s):  
Stephen J. Harvey ◽  
Robert M. Nowierski

The growth and development of leafy spurge (Euphorbia esulaL. #3EPHES) collected during postsenescent dormancy and grown in the greenhouse was increasingly stimulated by chilling treatments longer than 14 days duration at 0 to 6 C. Production of stems with flower buds, primary flowers, and secondary flowers was greater in plants chilled for 42 days or more. The effects of chilling on total number of stems, number of strictly vegetative stems, or number of stems with vegetative branching were not significant. The height of the tallest stem per pot was influenced by chilling longer than 42 days. Growth rate also increased as a function of chilling duration. Based on our findings, we believe that there is little possibility that any significant growth can occur in the postsenescent period because of the prevailing climatic conditions found in areas of leafy spurge distribution in North America.


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