The effects of inbreeding, maternal handicap, and range in age on 10 fleece and body characteristics in Merino rams and ewes

1967 ◽  
Vol 18 (4) ◽  
pp. 689 ◽  
Author(s):  
J Lax ◽  
GH Brown
Keyword(s):  
Body Weight ◽  
Positive Relationship ◽  
Age Groups ◽  
Fibre Diameter ◽  
Regression Coefficients ◽  
Multiple Births ◽  
Multiple Birth ◽  
Skin Area ◽  
Usual Practice ◽  
Body Weights

Estimates have been made of the influence on 10 fleece and body characteristics of dam's phenotype, range in age of offspring, inbreeding of offspring and dam, type of birth of offspring, and age of dam. The data came from rams 10–11 months old and ewes 15–16 months old, which had previously been shorn as weaners; the animals belong to an unselected control flock run at Cunnamulla, south-western Queensland. The dam's phenotype showed a high positive relationship with that of her offspring in all 10 characteristics, the values of the regression coefficients confirming the levels of heritability previously estimated on the same flock but without removing all the effects included in the present analysis. Younger animals in a group had lower greasy and clean wool weights and body weights, even at 15–16 months, but the effects were slight, except for body weight. For each 1% increase in the offspring's own level of inbreeding, the regression coefficients for rams and ewes respectively were -0.042 and –0,051 lb for greasy wool weight, –0.025 and –0.025 1b for clean wool weight, and –0.431 and –0.541 1b for body weight. These figures represent a decrease of 5–10% in clean wool weight and 8–10% in body weight for the progeny of half-sib matings. Inbreeding of the dam had a negligible effect on the characteristics examined. Animals born in multiple births in this environment suffer penalties which were still evident up to 15–16 months of age, resulting in both sexes in lower wool and body weights, lower wrinkle scores, fewer fibres per unit skin area, and fewer crimps per inch of staple. Fibre diameter was slightly higher for the multiple birth animals, but �he signs for the effects on other characteristics differed between sexes. The handicaps for rams and ewes respectively were 9 and 5% for clean wool weight and 7 and 5% for body weight. Dams were separated into four age groups (2, 3, 4–7, and 8–10 years). Greasy and clean wool weights and wrinkle score rose for offspring of both sexes to a peak at 4–7-year-old dams, then fell slightly. Body weight reached a peak at 3 years for rams and 4–7 years for ewes, while fibre diameter and staple length reached a peak at 3 years for ewes and 4–7 years for rams. In no case was the fall for the older dam age groups sufficient to invalidate the usual practice of adjusting only the progeny of 2-year-old dams. Other characteristics showed no consistent pattern.

Response to selection in Australian Merino sheep. III. Single character selection for high and low values of wool weight and its components

1970 ◽  
Vol 21 (6) ◽  
pp. 955 ◽  
Author(s):  
HN Turner ◽  
MG Brooker ◽  
CHS Dolling
Keyword(s):  
Body Weight ◽  
Unit Area ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Initial Response ◽  
Skin Area ◽  
Correlated Responses ◽  
Fibre Number ◽  
Selection For ◽  
Staple Length

Direct and correlated responses are reported for 10 traits in eight pairs of lines under selection for high and low values of single characteristics : clean wool weight per head, clean wool weight per unit skin area (measured only in the groups under selection for it), body weight, wrinkle score, fibre number per unit skin area (adjusted for body weight), fibre diameter, staple length, and percentage clean yield. All groups showed overall divergence in the character under selection, though response was not always symmetrical, and in two cases (long staple and low fibre number) there was no continuing response after the initial response to extreme selection of the base parents. In all except one case, whenever previous estimates of genetic correlation were at the level of 0.2 or higher, correlated responses were in the predicted direction, though not always symmetrical in magnitude. The exception was a previously reported negative correlation between fibre number and staple length, which was not exhibited under selection for either character. Where two characters of a pair were under selection, reciprocal responses agreed in sign; magnitude will be examined in a later paper. Wool per unit area was shown to have a greater influence on clean wool weight than that of surface area, with staple length on this occasion being the most important component of wool per unit area. Reasons for an apparent decrease in the relative importance of fibre number are discussed. Three other points of importance in sheep breeding are again emphasized by these results : 1. Crimp in several pairs of groups was a poor indicator of fibre diameter. 2. Increases in clean wool weight were associated with falls in crimp number, even though fibre diameter actually became finer; diameter, not crimp, should therefore be used as a guide to wool quality. 3. The absence of genetic correlations DL and NL indicates that selection can be for high N (fibre number) with high L (staple length) and low D (fibre diameter) -in other words, a desirable fleece -with no impeding genetic correlations.

Prediction of body weights of Nellore sheep under field condition

2015 ◽  
Author(s):  
M. Rani ◽  
B. Ekambaram ◽  
B. Punya Kumari
Keyword(s):  
Body Weight ◽  
Body Length ◽  
Age Groups ◽  
The Body ◽  
Coefficient Of Determination ◽  
Regression Equations ◽  
Body Weights ◽  
Chest Girth ◽  
Males And Females ◽  
Nellore Sheep

Data on 1350 Nellore sheep of 2, 4, 6 and 8-teeth age, reared under field conditions in 12 mandals of Chittoor district of Andhra Pradesh were utilized for development of prediction equations and study the phenotypic association among body measurements and body weights. The coefficients of correlation between body weight with the height at withers, chest girth, paunch girth, hip width and body length were positive and high in magnitude in both males and females in majority of the age groups studied. Step-down regression equations were fitted to predict the body weight based on biometrical measurements at different ages. The height at withers, chest girth, paunch girth, hip width and body length have contributed significantly to the expression of body weights at the majority of the ages studied. High coefficient of determination (R2) value was observed in males at 6 and 8-teeth age as 88 per cent, while in females 50 per cent at 2-teeth age.

scholarly journals PUBERAL DEVELOPMENT IN THE NIGERIAN DWARF SHEEP

2021 ◽  
Vol 7 (1) ◽  
pp. 71-76
Author(s):  
B. I. Orji ◽  
J. Steinbach
Keyword(s):  
Body Weight ◽  
Reproductive Tract ◽  
Age Groups ◽  
Reproductive Organs ◽  
The Body ◽  
Endocrine Function ◽  
Physiological Age ◽  
Body Weights ◽  
Pituitary Glands ◽  
Ram Lambs

Eleven ram lambs, all born between June and July (rainy season) were slaughtered at four age groups — 75, 100, 125 and 150 days. The body weights of animals prior to slaughter, the weights of the testes, the epididymis, the vesicular glands, the ampullae, the adrenals, the thyroids and the pituitary glands were determined and subjected to a step-wise multiple regression analysis using age or body weight as the independent variable. The weights of the reproductive organs – testes, epididymides, ampullae, vesicular glands - showed significantly higher correlation with the body weight than with the age, thus emphasizing the greater importance of the physiological age over the chronological age in the development of the body organs. The highest growth rate of the organs of the reproductive tract occurred during puberty and thus coincided with the enhanced endocrine function observed in ram lambs at this stage.

The effects of some variables on the components of reproduction rate in the Merino

1969 ◽  
Vol 20 (3) ◽  
pp. 549 ◽  
Author(s):  
Haas HJ De ◽  
AA Dunlop
Keyword(s):  
Body Weight ◽  
Error Variance ◽  
The Other ◽  
Multiple Births ◽  
Multiple Birth ◽  
Reproduction Rate ◽  
Components Of Variance ◽  
Estimated Error ◽  
Main Effects ◽  
Single Birth

Reproductive records covering 4855 ewe-years coming from five strains of Merino ewe run at three locations over 5 years were classified into those which resulted in (a) failure to lamb, (b) a single birth, or (c) a multiple birth. Age of ewe was included as a further classification, while pre-mating body weight was considered as a covariate. The data were analysed by least squares procedures. In all analyses in which components of variance were estimated, error variance constituted more than 90% of the total. Of the main effects, those due to age were generally largest, particularly where they related to the proportion of dry ewes and multiple births, though year effects on the proportion of dry ewes ranged up to 0.10. The effects of pre-mating body weight on lambing performance were small though real, the largest being an increase of 0.37% of multiple births per pound increase in body weight. First order interactions were generally small, the most prominent being location x strain, location x age, and location x year. The third of these had the largest effects and accounted for more of the variance. This was particularly so in the proportions of dry ewes and single births. Location x age interactions, on the other hand, were more prominent in affecting the proportion of multiple births, where the increase with age was much less marked at one location than at the other two. Strain x location interactions were not large enough to suggest any marked adaptation of strains to particular locations in these mutually dependent traits.

A comparison of the production of F1 and F2 Border Leicester × Merino ewes

1964 ◽  
Vol 4 (12) ◽  
pp. 80 ◽  
Author(s):  
WA Pattie ◽  
MD Smith
Keyword(s):  
Body Weight ◽  
Density Ratio ◽  
Fibre Diameter ◽  
The Other ◽  
Multiple Births ◽  
Significant Drop ◽  
Major Genes ◽  
Horn Growth ◽  
Production Characteristics ◽  
Staple Length

A comparison has been made of the production characteristics of 255 F1 and 288 F2 Border Leicester x Merino ewes. These sheep comprised a total drop of ewes born in a breed establishment trial in March-April 1960. There were no significant differences between the means of each group of ewes for the following characters : 18 month body weight, mutton score, fleece and breech score, yield, staple length, crimps per inch, fibre diameter, follicle density, ratio of primary to total follicles, and wool colour and character. The F1 ewes had significantly heavier greasy and clean fleece weights and showed significant though only slightly greater face cover scores. There was no significant increase in the variation of any character studied, in the F2 ewes. It is considered that these results are reasonable when the nature of inheritance of production characters, and their susceptibility to environment are considered. On the other hand the variance of horn growth, which is controlled by a few major genes, increased considerably in the F2 ewes. There was a large (40 per cent) and significant drop in fertility in the F2 ewes brought about by a drop in the number of wet ewes and multiple births, and an increase in lamb losses. The significance of these findings in relation to crossbreeding and breed establishment is discussed.

​POU1F1 Gene Polymorphism and its Associations with Body Weight of Osmanabadi Goat

2021 ◽  
Author(s):  
Vikrant D. Pawar ◽  
Mahadeo P. Sawane ◽  
Aakash Y. Doiphode
Keyword(s):  
Body Weight ◽  
Gene Polymorphism ◽  
Age Groups ◽  
Restriction Enzymes ◽  
Nucleotide Position ◽  
Pou1f1 Gene ◽  
Body Weights ◽  
Pcr Rflp ◽  
Indigenous Goat ◽  
Selection Of

Background: Osmanabadi is the premium meat type goat breed of Maharashtra, known for its adaptability and reproductive efficiency. Identification of superior germplasm and incorporating them into breeding programme is the need of hour for augmenting productivity of Osmanabadi as well as other indigenous goat breeds. Hence, the present research was aimed to study Pituitary Specific Transcription Factor I (POU1F1) gene polymorphism and its associations with body weight of Osmanabadi goat. Methods: Genomic DNA was extracted from 217 blood samples of randomly selected Osmanabadi goats. The 450 bp fragment of POU1F1 gene encompassing exon-6 and its flanking region (3’UTR) was PCR amplified. The PCR amplicon was subjected to RFLP using AluI and PstI restriction enzymes to identify polymorphism at nucleotide position 174 (T greater than C) in exon 6 and at nucleotide position 110 (T greater than C) in the 3’UTR of POU1F1 gene, respectively. The association of the observed allelic variants / genotypes with body weight of the animals was performed using One-way ANOVA. Result: The AluI PCR-RFLP of 450 bp amplicon of POU1F1 gene in Osmanabadi goats revealed polymorphism with three different genotypes viz., ‘CC’, ‘TT’ and ‘TC’. The observed frequencies for TT, TC and CC genotypes were 0.604, 0.355 and 0.041 respectively. The frequencies of T and C alleles were found to be 0.781 and 0.219, respectively. However, PstI PCR-RFLP revealed monomorphic 3’UTR of POU1F1 gene with single TT genotype. We observed significant differences (P less than 0.01) between various genotypes at AluI exon-6 locus of POU1F1 gene and body weights at birth, 3 and 6 months of Osmanabadi goat. Highest body weight was recorded for TT genotype followed by TC and CC genotypes in all three age groups. Our findings indicate that the AluI PCR-RFLP locus of the exon-6 of POU1F1 gene can be used as a potent molecular marker for selection of superior stock of Osmanabadi goats.

Effects of crossbreeding and certain environmental factors on multiple births, wool production and growth in sheep

1973 ◽  
Vol 16 (2) ◽  
pp. 147-155 ◽  
Author(s):  
M. H. Fahmy ◽  
C. S. Bernard
Keyword(s):  
Body Weight ◽  
Environmental Factors ◽  
The Other ◽  
Multiple Births ◽  
Multiple Birth ◽  
Wool Production ◽  
Breed Group ◽  
Reproductive Life ◽  
Fleece Weight ◽  
Maximum Body

SUMMARYMultiple birth percentage and wool production were studied on 338 ewes (907 lambing and 873 shearing records) representing two purebreds, Oxford (O) and Suffolk (S), and four crossbreds, O × S, S × O, Cheviot (C) × O and C × S mated to purebred and crossbred rams during 9 years. Oxford ewes had 24–32% (P<0·01) fewer multiple births than ewes of the other groups, while little difference between S and the crossbreds was observed. The heterosis of the OS and SO groups was 14·6 ± 4·1%. Multiple births tended to increase 0·8% for each kg increase in body weight of the dam (r = 0·13). The repeatability estimate for multiple births was 0·24. Fleece weight was significantly affected by age and by breed group, with OS and SO crosses producing 17% more wool than their parental breeds. The repeatability of fleece weight was estimated at 0·52 ± 0·15. Fleece weight was significantly correlated with multiple birth percentage (0·09) and body weight (0·32).Suffolk ewes averaged 9·5 kg heavier than O ewes throughout their reproductive life. The two reciprocal crosses were heavier than both parental breeds. Suffolk ewes reached their maximum body weight at 4 years of age while Oxfords continued to gain weight up to 6 years.

A note on the use of sarcomere length measurements as predictors of longitudinal growth in skeletal muscles

1974 ◽  
Vol 18 (1) ◽  
pp. 97-100
Author(s):  
P. V. J. Hegarty
Keyword(s):  
Body Weight ◽  
Skeletal Muscles ◽  
Sarcomere Length ◽  
Biceps Brachii ◽  
Fibre Diameter ◽  
Longitudinal Growth ◽  
Rigor Mortis ◽  
Limb Position ◽  
Body Weights ◽  
Length Measurements

SUMMARYSarcomere length and fibre diameter were measured in the biceps brachii and sternomastoideus muscles from 35 male mice (5·3-38·0 g body weight). The fore-limbs of each animal were either folded or stretched maximally immediately post mortem and allowed to go into rigor mortis in that position. Unfixed isolated fibres were separated and the sarcomere length and fibre diameter measured. Sarcomere length remained unchanged with increasing body weight irrespective of whether the muscles were in the folded or stretched position. Sarcomere length was shorter in the folded biceps brachii (P < 0·01) and sternomastoideus (P < 0·05) than in the corresponding stretched muscles at all body weights. The results indicate that sarcomere length cannot be used as an indicator of the longitudinal growth of muscle, and that limb position during rigor development is a significant factor in altering sarcomere length.

scholarly journals Effects of aging, phenotype and carbohydrate feeding on caloric efficiency and adiposity in the LA/Ntul//-cp (corpulent) rat

2021 ◽  
Vol 11 (1) ◽  
pp. 5-11
Author(s):  
Orien L Tulp
Keyword(s):  
Body Weight ◽  
Sucrose Solution ◽  
Age Groups ◽  
Caloric Intake ◽  
Energy Utilization ◽  
Caloric Efficiency ◽  
Carbohydrate Feeding ◽  
Body Weights ◽  
Obese Phenotype ◽  
Effects Of Aging

Obesity develops in the obese phenotype of the LA/Ntul//-cp (corpulent) specific pathogen-free rat strain by 5 to 6 weeks of age. Groups [n=12 -20 rats/phenotype] of female congenic lean and obese LA/Ntul//-cp (corpulent) rats were fed ad libitum standardized Purina diets for 4, 14, or 24 months or the same diet plus a 16% (w/v) sucrose solution supplement from 12 weeks of age, and measures of body weight, caloric intake, and caloric efficiency (CE) determined at each age group. Body weights of lean animals remained similar at all ages studied, while body weights of obese phenotype were significantly greater than their lean littermates at each age studied. The sucrose supplement was without significant effect on final body weights in the lean phenotypes at all ages studied (p=n.s.) but were associated with greater body weights at ages 4, 14 and 24 months of age in the obese phenotype (p=<0.05). CE was determined as the ratio of kcal/gram of body weight per day remained relatively constant in lean animals throughout the age range, but CE was more efficient in the obese phenotype at all ages studied and became progressively more efficient with the sucrose supplement feeding with increasing age. The results of this study indicate that CE is associated with the predisposition for the development of obesity in the obese phenotype of this strain and likely implicates multiple metabolic factors that contribute to a greater efficiency of energy utilization and or energy conservation in the obese than in the lean phenotype of this strain, and the metabolic impact of added sucrose was associated with an additive impact on the CE of weight gain and adiposity in the obese phenotype of this congenic rodent strain

The effects of body weight and level of nutrition before, during, and after joining on ewe fertility

1967 ◽  
Vol 7 (25) ◽  
pp. 126 ◽  
Author(s):  
ID Killeen
Keyword(s):  
Body Weight ◽  
Reproductive Performance ◽  
Ovulation Rate ◽  
Multiple Birth ◽  
Corpora Lutea ◽  
Body Weights ◽  
Before And After ◽  
Independent Effects ◽  
Experimental Treatments ◽  
High Level

Four experiments were designed to assess the independent effects of body weight and nutritional level on the reproductive performance of Border Leicester x Merino ewes. Ewes in experiments 1, 2, and 3 were joined in summer (December-January) and in experiment 4 in autumn (March-April). The reproductive performance of two groups of ewes in experiment 1, joined at different body weights, was assessed from mating and lambing data. A factorial (3 x 2 x 2) design was used for experiments 2, 3, and 4. The experimental treatments consisted of different levels of nutrition applied before and after mating. The reproductive performance of ewes in experiment 2 was assessed from mating and lambing data. Ewes in experiments 3 and 4 were slaughtered 19-28 days after mating, and their genitalia were observed for presence of corpora lutea and embryos. Body weight at mating and level of nutrition during three weeks before mating independently affected the multiple birth or ovulation rate. High body weight at mating was consistent with a high multiple birth or ovulation rate, and a higher proportion of the ewes receiving a high level of nutrition during the three weeks before mating (i.e. flushed ewes) had multiple births or multiple ovulations. The results also demonstrated that above 90-100 lb, the proportion of ewes mating and becoming pregnant was relatively independent of body weight at joining. The level of nutrition and body weight had only minor effects on early reproductive failure, but there was a higher proportion of egg wastage from multiple ovulation ewes than from single ovulation ewes.

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