Crossbreeding and the effect of certain environmental factors on body weights of Barki and German Merino sheep

1974 ◽  
Vol 82 (2) ◽  
pp. 349-352 ◽  
Author(s):  
M. H. El Kouni ◽  
H. A. Karam ◽  
E. S. E. Galal ◽  
E. A. Afifi
Keyword(s):  
Environmental Factors ◽  
Merino Sheep ◽  
Body Weights ◽  
Sources Of Variation ◽  
Effect Of Age

SummaryBody weights at birth, weaning, yearling and 2 years of age were studied on 710 lambs born from 1956 to 1967 and representing Barki, Merino and their F1 and backcross. Body weights ofthe lambs of the two cross-bred groups were intermediate between those of the two pure-breds at birth and exceeded them at weaning. Merino lambs were 0·61 kg heavier than Barki lambs at birth and maintained that advantage throughout the study.Age of dam, type of birth, sex, and year of birth were significant sources of variation on the weights studied. The effect of age of dam and type of birth declined after weaning while that of sex increased.

scholarly journals On the Etiology of Aesthetic Chills: a Behavioral Genetic Study

2021 ◽  
Author(s):  
Giacomo Bignardi ◽  
Rebecca Chamberlain ◽  
Sofieke T Kevenaar ◽  
Zenab Tamimy ◽  
Dorret I Boomsma
Keyword(s):  
Individual Differences ◽  
Environmental Factors ◽  
The Netherlands ◽  
Genetic Study ◽  
Genetic Model ◽  
Physiological Factors ◽  
Somatic Marker ◽  
Show Evidence ◽  
Sources Of Variation ◽  
Behavioral Genetic Study

Aesthetic chills, broadly defined as a somatic marker of peak emotional-hedonic responses, are experienced by individuals across a variety of human cultures. Yet individuals vary widely in the propensity of feeling them. These individual differences have been studied in relation to demographics, personality, and neurobiological and physiological factors, but no study to date has explored the genetic etiological sources of variation. To partition genetic and environmental sources of variation in the propensity of feeling aesthetic chills, we fitted a biometrical genetic model to data from 14127 twins (from 8995 pairs), collected by the Netherlands Twin Register. Both genetic and unique environmental factors accounted for variance in aesthetic chills, with heritability estimated at .36 ([.33, .39] 95% CI). We found females more prone than males to report feeling aesthetic chills. However, a test for genotype x sex interaction did not show evidence that heritability differs between sexes. We thus show that the propensity of feeling aesthetic chills is not shaped by nurture alone, but it also reflects underlying genetic propensities.

scholarly journals Some non-genetic sources of variation in body weight in six commercial flocks of Merino sheep in Egypt

1978 ◽  
Vol 18 (1) ◽  
pp. 1-12
Author(s):  
A. Abdel-Aziz ◽  
M. Ragab ◽  
M. Sharafeldin ◽  
S. Imam
Keyword(s):  
Body Weight ◽  
Merino Sheep ◽  
Sources Of Variation

Effect of Age and Environmental Factors on Glucose Tolerance and Insulin Secretion in a Worker Population

1986 ◽  
Vol 34 (4) ◽  
pp. 271-275 ◽  
Author(s):  
I. Zavaroni ◽  
E. Dall'Aglio ◽  
F. Bruschi ◽  
E. Bonora ◽  
O. Alpi ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Environmental Factors ◽  
Glucose Tolerance ◽  
Effect Of Age

Comparative water consumption and efficiency in three divergent sheep types

1995 ◽  
Vol 124 (1) ◽  
pp. 139-143 ◽  
Author(s):  
S. J. Schoeman ◽  
J. A. Visser
Keyword(s):  
Weight Gain ◽  
Water Consumption ◽  
Production Systems ◽  
Merino Sheep ◽  
Ewe Lambs ◽  
University Of Pretoria ◽  
Body Weights ◽  
Sheep Production ◽  
The University ◽  
Absolute Basis

SUMMARYCumulative feed and water intakes and body weights of 30 growing ewe lambs of three different breeds were recorded weekly for 34 weeks between October 1990 and June 1991 at the Experimental Farm of the University of Pretoria. The results were analysed to obtain water efficiencies on both an absolute and metabolic weight gain basis. On an absolute basis, Mutton Merino sheep consumed 145% and Dorper 109% more water than Blackhead Persian sheep. On a metabolic weight gain basis, the corresponding differences were 92 and 66%, respectively. Mutton Merino and Dorper lambs also consumed 69 and 41% more water per kg feed intake than the Blackhead Persians, respectively. Weekly water consumption increased twice as much per 1 °C increase in ambient temperature in the Dorper and Mutton Merino lambs as in the Blackhead Persians. These results suggest that sheep of the Blackhead Persian, and probably also other indigenous breeds, balance their water requirements at a more economical level and would be a more appropriate choice than those breeds currently being managed in sustainable sheep production systems in areas where water availability is limited.

Maintenance rations for Merino sheep. IV. The performance of adult Merino ewes fed daily and weekly at three levels of energy intake

1957 ◽  
Vol 8 (1) ◽  
pp. 75 ◽  
Author(s):  
PK Briggs ◽  
MC Franklin ◽  
GL McClymont
Keyword(s):  
Body Weight ◽  
Sodium Chloride ◽  
Energy Intake ◽  
Survival Rates ◽  
Experimental Period ◽  
The Body ◽  
Merino Sheep ◽  
Wool Production ◽  
Body Weights ◽  
The Mean

Dry adult Merino ewes were fed at daily or weekly intervals on oat grain at levels which provided 4.0, 3.0, or 2.0 lb starch equivalent (S.E.) per sheep per week. The experimental periods were 223, 223, and 181 days respectively. Differences between the mean body weights of the ewes a t the three levels of feeding were highly significant (P < 0.001). Body weight varied only slightly and no losses occurred in ewes fed weekly at the rate of 4.0 lb S.E. per head. Ewes fed daily a t this level had a significantly greater mean body weight (P < 0.001) a t the conclusion of the 223-day experimental period. The addition of a sodium chloride supplement did not improve the body weight or wool production of ewes fed weekly a t the level of 4.0 lb S.E. The mean body weight of ewes fed at the levels of 3.0 or 2.0 lb S.E. per head declined over the first 12 and 18 respectively and thereafter remained relatively constant. There were no significant differences at these levels of feeding between groups fed daily and weekly in respect of body weight, wool production, or survival rates. Ewes fed a t the level of 4.0 lb S.E. grew significantly more wool than those given 3.0 lb S.E. (P < 0.001). Losses were negligible in all groups except those fed a t the level of 2.0 lb S.E. In these groups there were few deaths in the first 16 weeks, but in the subsequent 10 weeks losses totalled 17.1 per cent. Ewes fed a t the level of 2.0 lb S.E. consumed their rations at a significantly slower rate (P < 0.01) than did those fed a t the level of 4.0 lb S.E.

Effect of age at weaning on the subsequent growth of artificially reared lambs

1974 ◽  
Vol 14 (71) ◽  
pp. 720
Author(s):  
JA Levick ◽  
GR Pearce
Keyword(s):  
Liquid Diet ◽  
The Body ◽  
Subsequent Growth ◽  
Body Weights ◽  
Effect Of Age

Lambs were removed from their dams at 0, 1, 3 and 7 days of age and reared artificially on a liquid diet. Lambs weaned at 7 days suffered a more prolonged check to growth than other lambs but the body weights of all lambs were similar at 28 days of age. Lambs weaned at 7 days required considerably more handling before they would drink voluntarily from rubber teats.

The effect of age and diet on the reproductive performance of Sudan Nilotic ewes

2005 ◽  
Vol 143 (5) ◽  
pp. 421-426 ◽  
Author(s):  
M. ATTA ◽  
O. A. EL KHIDIR
Keyword(s):  
Reproductive Performance ◽  
Research Centre ◽  
Southern Sudan ◽  
Oil Cakes ◽  
Body Weights ◽  
Sorghum Grains ◽  
Mortality Proportion ◽  
Production Research ◽  
Similar Body ◽  
Effect Of Age

Two flocks of 42 multiparous (M) and 27 primiparous (P) Nilotic ewes (Southern Sudan) were used in an experiment conducted at the Animal Production Research Centre, Khartoum N., Sudan, to study the effect of age and diet on reproductive performance. Each age group (M and P) was subdivided into two diet groups, fed either a sorghum (So) or a molasses (Mo)-based diet. The two diets were approximately isoenergetic (12·2 and 11·4 MJ ME/kg DM for So and Mo diets, respectively) and isonitrogenous (217 g CP/kg). These diets were formulated from sorghum and groundnut cake or molasses and urea as main sources of energy and protein, respectively. Each of the four diet groups of ewes was further divided into 6 subgroups (replicates) of similar body weights housed and fed together for two successive gestation periods. The results showed that the diet treatments had no significant effect on age and weights at first oestrous (210, 238 days and 22, 20 kg) and at first lambing (407, 418 days and 30, 28 kg) of the PSo and PMo groups, respectively. Age of the ewes and the diet treatments had no significant effects (P>0·05) on feed intake, conception weight, litter size, lamb birth weight, gestation period, postpartum anoestrous period, lambing interval, sex ratio of offspring as well as conception, fertility, abortion and lambing proportions. Primiparous ewes (P) had significantly (P<0·05) higher pre-weaning lamb mortality proportion, whereas the sorghum-based diet groups had higher (P<0·05) gestation body gain and lambing weights.It was concluded that Nilotic ewes, compared with the other African sheep breeds reviewed, reach sexual maturity at an earlier age and are highly prolific due to their short postpartum anoestrous period. The results also highlight the importance of molasses and urea as efficient and good substitutes for sorghum grains and oil cakes, respectively, in the diets of ewes.

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