scholarly journals Comparison of performance of F1 Romanov crossbred ewes with wool and hair breeds during fall lambing and body weight and longevity through 6 production years

2020 ◽  
Author(s):  
T W Murphy ◽  
B A Freking
Keyword(s):  
Body Weight ◽  
Litter Size ◽  
Total Weight ◽  
Breed Differences ◽  
Lamb Survival ◽  
Sire Breed ◽  
Maternal Grandsire ◽  
Size At Birth ◽  
Birth Type

Abstract Objective was to evaluate wool (Dorset and Rambouillet) and hair (Dorper, Katahdin, and White Dorper) breeds for their ability to complement Romanov germplasm in an annual fall lambing system by estimating direct maternal grandsire and sire breed effects on economically important lamb and ewe traits. After 3 yr of evaluation under spring lambing, ewes of the 5 F1 types were transitioned to spring mating, exposed to composite terminal sires, and evaluated under a barn lambing system at 4, 5, and 6 yr of age. A total of 527 F1 crossbred ewes produced 1151 litters and 2248 lambs from 1378 May exposures. After accounting for differences in dam age, birth type, and sex, lamb survival to weaning was unaffected by maternal grandsire breed (P = 0.30). However, lambs born to 50% Dorset (16.8 ± 0.21 kg) or 50% White Dorper ewes (16.8 ± 0.28 kg) were heavier at weaning than those born to 50% Katahdin dams (13.8 ± 0.32 kg; P < 0.001). Additionally, lambs born to 50% Dorset ewes were heavier than those born to 50% Rambouillet (16.0 ± 0.22 kg) and 50% Dorper ewes (15.7 ± 0.33; P ≤ 0.03), but no other pairwise maternal grandsire breed differences were observed (P ≥ 0.06). Ewe body weight (n = 3629) was recorded prior to each of 6 possible mating seasons and, across ages, was greatest for Dorset and Rambouillet sired ewes (56.7 ± 0.44 and 56.5 ± 0.45 kg, respectively), intermediate for Dorper and White Dorper sired ewes (54.7 ± 0.78 and 54.1 ± 0.64 kg, respectively), and least for Katahdin sired ewes (51.5 ± 0.45 kg). Fertility after spring mating (0.80 ± 0.03 to 0.87 ± 0.02), litter size at birth (1.46 ± 0.09 to 1.71 ± 0.07), and litter size at weaning (1.25 ± 0.06 to 1.46 ± 0.06) were not impacted by sire breed (P ≥ 0.16). Ewe longevity, assessed as the probability of being present after 6 production years, was also not affected by sire breed (0.39 ± 0.03 to 0.47 ± 0.03; P = 0.44). Rambouillet sired ewes weaned more total weight of lamb (21.5 ± 0.94 kg) than Katahdin sired ewes (17.8 ± 0.94 kg; P = 0.05), but no other sire breed differences were detected (P ≥ 0.07). Results demonstrated that incorporating the Romanov into a crossbreeding system is a practical means of improving out-of-season ewe productivity.

Maternal performance in sheep as affected by breed, crossbreeding and other factors

1975 ◽  
Vol 20 (1) ◽  
pp. 19-30 ◽  
Author(s):  
Gerald Wiener ◽  
Susan Hayter
Keyword(s):  
Significant Variation ◽  
Total Weight ◽  
Breed Differences ◽  
Maternal Performance ◽  
Lamb Survival ◽  
Female Sheep ◽  
Birth Type

SUMMARYMaternal performance of female sheep of three hill breeds, Scottish Blackface, Cheviot and Welsh Mountain, and the crosses among these breeds has been studied in terms of lifetime production and some of its components. The data are based on 193 ewes, which were given the opportunity of having four annual lamb crops, and their lambs.There was no significant variation among the breeds and crosses in ewe survival or in the proportion of barren ewes at each lambing. There was significant variation among the breeds and crosses in the number of lambs born per ewe lambing, in lamb survival and in weights of lamb at birth and at weaning. Crossbred ewes (producing crossbred lambs) had more and heavier lambs than expected from the average of the pure breeds contributing to each cross, but the three crossbred types differed in the amount of heterosis shown. Over their lifetime in the flock there were significant breed differences in the total weight of lambs weaned, with crossbred ewes producing about 9% more than the average of the parent breeds involved. The crossbred ewes produced more weight of lambs over their lifetime than pure Cheviot or pure Welsh Mountain ewes, but not as much as pure Scottish Blackface.Effects of parity of dam and of sex, birth type, and type of rearing of lamb are given.

THE ACCUMULATIVE EFFECT OF FINNSHEEP BREEDING IN CROSSBREEDING SCHEMES: REPRODUCTIVE PERFORMANCE

1988 ◽  
Vol 68 (1) ◽  
pp. 69-81 ◽  
Author(s):  
MOHAMED H. FAHMY ◽  
JACQUES J. DUFOUR
Keyword(s):  
Body Weight ◽  
Mortality Rate ◽  
Key Words ◽  
Litter Size ◽  
Reproductive Performance ◽  
Conception Rate ◽  
Ovulation Rate ◽  
Genetic Groups ◽  
Linear Regressions ◽  
Size At Birth

Reproductive performance and body weight were studied on 361 ewes, representing Finnsheep (F), DLS (a population of 1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) and seven combinations ranging from 1/8 to 7/8 Finnsheep breeding. Conception rate in yearlings was 61.5% for DLS compared to 89.0% for F with the crosses being intermediate. Conception rate in older ewes was similar in the different genetic groups (avg. 94%). Ovulation rate and litter size at birth of DLS ewes were 1.72 and 1.44 lambs, which was less than half those of F ewes (3.51 and 2.86 lambs, respectively). Both traits increased progressively with an increase in F breeding in crosses and with advances in age. DLS ewes weaned 1.22 lambs compared to 2.03 lambs for F ewes and 1.84 lambs for 4/8 F ewes. The heaviest litters at weaning (31.7 kg) were raised by 4/8 F ewes, followed by 7/8 F (30.8 kg) while those raised by DLS ewes weighed 23.0 kg and F ewes 29.1 kg. Percentage of ova lost per ewe mated averaged 24% and ranged between 18% (DLS and 1/8 F) and 29% (6/8 F). About 3.6% of lambs were born dead and a further 13.8% died before weaning. Preweaning mortality rate was highest in F (22.9%) and lowest in 3/8 F (9.4%). Average kilograms of lambs weaned per ewe exposed was highest in 4/8 F (27.6 kg) followed by F (26.0 kg), whereas that of DLS was the lowest at 18.1 kg. The 4/8 F cross showed 25% heterosis in kg of lambs weaned per ewe exposed and 52.5% increase over DLS. Significant positive linear regressions were calculated for ovulation rate, litter size and preweaning mortality rate on proportion of Finnsheep breeding in crosses. The relation was quadratic for percent ova lost and lamb mortality at weaning. Yearling DLS females weighted 36 kg compared to 44 kg for F yearlings. However, at 5 yr of age DLS ewes weighed 62 kg, 5 kg heavier than F ewes. The heaviest ewes at all ages were the 4/8 F (45 kg at 1 yr, 65 kg at 5 yr). Key words: Reproduction, DLS sheep, Finnsheep, crossbreeding, heterosis, repeatabilities

Estimates Of Genetic Parameters For Economic Traits In West African Dwarf Goat

2021 ◽  
Vol 19 ◽  
pp. 114-119
Author(s):  
I. K. Odubote ◽  
J. O. Akinokun
Keyword(s):  
Body Weight ◽  
Litter Size ◽  
Genetic Parameters ◽  
West African ◽  
Economic Traits ◽  
West African Dwarf ◽  
West African Dwarf Goat ◽  
Heritability Estimates ◽  
Size At Birth ◽  
Birth Body Weight

Records of 848 West African Dwarf goat kids and 220 kiddings over a period of eight years (1982-1989) were analysed. The records were used to provide heritability and repeatability estimates for litter size at birth, kidding interval (repeatability estimate alone) and body weight at birth, weaning, 3 months, 6 months, 9 months and 1 year of age. Heritability estimates of 0.28±0.005, 0.18±0.003, 0.14±0.003, 0.29±0.005, 0.11±0.003 and 0.17±0.004 were obtained for litter size at birth, body weight at birth, and at weaning, 3 months, 6 months, and 9 months of age respectively. Corresponding repeatability estimates were slightly higher than the heritability estimates. However, repeatability estimates of 0.04±0.030 was obtained for kidding interval.

PSXII-29 Evaluation of Barbados Blackbelly and St. Croix sheep under accelerated lambing using purebred and terminal sire mating: Lamb survival and body weight

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 488-489
Author(s):  
Stephan Wildeus ◽  
Tom Murphy ◽  
Dahlia O’Brien
Keyword(s):  
Body Weight ◽  
Mating System ◽  
Fixed Effects ◽  
Production Systems ◽  
Management Tool ◽  
Birth Month ◽  
Increase Productivity ◽  
Lamb Survival ◽  
Terminal Sire ◽  
Birth Type

Abstract Objectives were to evaluate lamb survival and body weight (BW) under an accelerated, pasture-lambing system. Lambs were born to Barbados Blackbelly (BB) or St. Croix dams (SC) mated within breed (purebred) or to Dorset (terminal) in single sire mating groups. Lambs were born in April (2013 and 2015), December (2013 and 2015), and August (2014 and 2016) and weaned at 9 weeks of age. Traits considered were BW at birth (BW0; n = 959), 65-d adjusted weaning BW (BW65; n = 788), and survival to weaning (n = 959). Data were analyzed with fixed effects of dam age, sex, birth type, dam breed (BB vs SC), dam mating system (purebred vs terminal), birth month-year, and significant two-way interactions and a random dam effect. Dam breed did not impact BW65 (P = 0.09). While BW0 was greater for lambs born to SC than BB dams (3.44 vs 3.23 kg; P < 0.01), survival to weaning was greater for lambs born to BB than SC dams (0.93 vs. 0.87; P = 0.02). The dam mating system x birth month-year interaction was significant for both BW traits (P ≤ 0.01). Within birth month-year, BW0 was 18 to 24% greater and BW65 was 12 to 24% greater for terminal than purebred lambs (P < 0.01). However, BW0 differences between dam mating systems were greatest for August born lambs whereas BW65 differences were greatest for April born lambs. Lamb survival was not affected by dam mating system or birth month-year (P ≥ 0.27). Using a terminal sire improved BW without affecting survival of lambs reared by landrace hair sheep dams, making this a viable management tool to increase productivity of forage-based production systems.

scholarly journals Reproductive Biology of the Booroola Merino Sheep

1984 ◽  
Vol 37 (3) ◽  
pp. 163 ◽  
Author(s):  
BM Bindon
Keyword(s):  
Reproductive Biology ◽  
Litter Size ◽  
Single Gene ◽  
Ovulation Rate ◽  
Physiological Characteristics ◽  
Merino Sheep ◽  
Sheep Breeds ◽  
The World ◽  
Lamb Survival ◽  
Size At Birth

This paper reviews the genetic and physiological characteristics of the Booroola Merino, one of the four most prolific sheep breeds in the world, and which was acquired by CSIRO in 1958 from a commercial sheep property, 'Booroola', Cooma, N.S.W. The exceptional prolificacy of this genotypee. g. mean flock ovulation rate in 1982 of 4�2 (range 1-10) and mean litter size of 2� 5 (range 1-7)is largely attributable to a single gene (F) of uncertain origin which increases ovulation rate. Crosses of the Booroola with other Merinos produce progeny which have a 47-87% increase in ovulation rate, a 45-56% increase in litter size at birth, and a 1-33% reduction in lamb survival relative to control Merinos. This represents a 16-37% increase in the number of lambs weaned per ewe joined in favour of the Booroola crosses.

scholarly journals Effect of body weight at first mating on reproductive performance of rabbit does

2020 ◽  
Vol 46 (5) ◽  
Author(s):  
O. Y. Ayo-Ajasa ◽  
L.T. Egbeyale ◽  
F. A. Adewole ◽  
D. A. Ekunseitan ◽  
O. A. Babalola
Keyword(s):  
Body Weight ◽  
Litter Size ◽  
Reproductive Performance ◽  
Reproductive Parameters ◽  
Initial Body Weight ◽  
Average Birth Weight ◽  
Statistical Representation ◽  
T1 And T2 ◽  
Breeding Efficiency ◽  
Size At Birth

Eighteen mature nulliparous rabbit does with initial body weight between 1600g-2500g were used to evaluate the effect of body weight at first mating on reproductive performance of rabbit does. These rabbits were assigned into three treatments, with T1, T2 and T3 weighing (1600-1900), (1901-2200) and (2201-2500) respectively. The study lasted for 5weeks. The does were mated with buck at ratio 1:3. The reproductive parameters evaluated were number of does that kindled, litter size at birth, breeding efficiency, litter size at weaning, pre-weaning loss. All data collected were subjected to descriptive statistical representation. The highest number of kindled does was 5 in T2 and T3; T1 had the lowest number (3). Breeding efficiency of 83.33% was recorded in T1 and T2 while T3 had 50.00%. T3 had highest average birth weight (49.51g) and T2 had the least (41.51g); litter size at birth and weaning ranged from 18 -28kits and 15-24kits, respectively. T2 does recorded highest value in both parameters, T3 does recorded same value (28kits) for litter size at birth. Highest pre-weaning loss of 7kits was recorded from does in T3 while T1 and T2 recorded 4kits. It was therefore concluded that does with weight range 1901g – 2200g had better reproductive performance with highest breeding efficiency and lower pre-weaning loss.

scholarly journals Niğde İlinde Yetiştirilen Akkaraman Irkı Koyunların Bazı Döl Verim Özellikleri ve Kuzuların Büyüme Performansı

2019 ◽  
Vol 7 (10) ◽  
pp. 1509
Author(s):  
Ayhan Ceyhan ◽  
Ahmet Şekeroğlu ◽  
Mustafa Duman
Keyword(s):  
Body Weight ◽  
Birth Weight ◽  
Growth Performance ◽  
Litter Size ◽  
Growth Characteristics ◽  
Improvement Project ◽  
Average Litter Size ◽  
Age And Sex ◽  
Birth Type ◽  
Lambing Rate

In this study, growth performance of Akkaraman lambs and some fertility parameters of Akkaraman sheep raised in semi extensive farm conditions were investigated. A total of 6300 heads Akkaraman ewes (6000 ewes and 300 rams) housed in 34 farms located in central villages of Niğde province were evaluated between 2012 and 2016. The data of birth weight of 30161 lambs, body weight of 29517 lambs aged 90 days old and some fertility parameters of 30000 heads ewes were used. The average lambing rate of ewes was found 90.1%. The twining rate of ewes was 20.8%; the average litter size was 1.12 lambs. Birth weights of Akkaraman sheep lambs was 4.23 kg, average 90th day live weights were 23.05 kg. Effects of year, birth type, dam age, and sex were found statistically significant on birth and 90-day live weights of the Akkaraman lambs. As a result, it was concluded that the fertility of Akkaraman sheep and growth characteristics of lambs raised by public under semi-extensive conditions could be improved and the economic situation of sheep farms could be better by the implementation such improvement project.

Genetic evaluation of crossbred lamb production. 1. Breed and fixed effects for birth and weaning weight of first-cross lambs, gestation length, and reproduction of base ewes

2005 ◽  
Vol 56 (5) ◽  
pp. 443 ◽  
Author(s):  
N. M. Fogarty ◽  
V. M. Ingham ◽  
A. R. Gilmour ◽  
L. J. Cummins ◽  
G. M. Gaunt ◽  
...  
Keyword(s):  
Litter Size ◽  
Fixed Effects ◽  
Mixed Model ◽  
Genetic Evaluation ◽  
Gestation Length ◽  
Production Traits ◽  
Weaning Weight ◽  
Frozen Semen ◽  
Lamb Survival ◽  
Sire Breed

This is the first paper in a series that reports on a national maternal sire central progeny test program (MCPT) to evaluate the genetic variation for economically important production traits in first- and second-cross progeny of maternal and dual purpose (meat and wool) sires and the scope for genetic improvement. The MCPT program also provides direct linkages between breeds that will contribute information for across-breed genetic evaluation. Crossbred progeny by 91 sires from more than 7 maternal breeds (including Border Leicester, East Friesian, Finnsheep, Coopworth, White Suffolk, Corriedale, and Booroola Leicester) at 3 sites over 3 years with 3 link sires in common at each site and year were evaluated in this study. National estimated breeding values for the sires that were entered by industry breeders indicated that there was some selection for weight, but not other traits and the sires were generally representative of the maternal genetics available to the industry. There were 8377 base Merino and Corriedale ewes artificially inseminated with thawed-frozen semen from the 91 sires and 8193 crossbred lambs born and 6117 lambs weaned. Mixed model analyses of birth and weaning weight, lamb survival, and gestation length as well as fertility, litter size, and lamb weaning rate of the base ewes are reported. Sire breed was significant for birth weight (with a range of 4.0–4.4 kg at an average litter size of 1.8) and weaning weight (19.6–22.5 kg), as well as lamb survival (70–79%) and gestation length (147.1–150.3 days). Birth/rearing type was significant for all traits. Males were significantly heavier than females at birth and weaning, although there was no sex difference for lamb survival or gestation length when birthweight was included in the model. Pregnancy rate from the artificially inseminated base ewes varied from 40 to 84% at the 3 locations in the various years. Sire breed was significant for the number of lambs weaned per ewe lambing, but not for fetal number or litter size born. There were also significant differences in performance due to the source of the base ewes at each site.

Breed and sex differences in muscle distribution in equally mature sheep

1980 ◽  
Vol 30 (1) ◽  
pp. 125-133 ◽  
Author(s):  
C. S. Taylor ◽  
M. A. Mason ◽  
T. H. McClelland
Keyword(s):  
Body Weight ◽  
Sex Differences ◽  
Total Weight ◽  
Muscle Weight ◽  
Percentage Decrease ◽  
Individual Muscle ◽  
Breed Differences ◽  
The Individual ◽  
Percentage Basis ◽  
Total Muscle

ABSTRACTSheep from the Soay, Southdown, Finnish Landrace and Oxford Down breeds were serially slaughtered at 40, 52, 64 and 76% of their estimated mature body weight. Breed and sex comparisons of muscle distribution wee made at these degrees of maturity. Comparisons were based on 12 individual muscles obtained from the prime retailjoints. Together, these 12 muscles represented about 41 % of total weight ofmuscle in the carcass. Highly significant breed and sex differences in the weight of individual muscles were obtained, but these differences were greatly reduced when values were expressed as a percentage of total muscle weight.On a percentage basis, there were significant changes with stage of maturity in only three of the muscles studied, although most individual muscles showed an initial percentage decrease with increasing maturity (from 40 to 52%) but almost no change thereafter. Significant breed differences in muscle distribution were found. The individual muscles examined, when combined, comprised 40·8, 43·4, 40·5 and 39·8 % of total muscle weight respectively in the Soay, Southdown, Finnish Landrace and Oxford Down. No breed was significantly above average for every individual muscle, but the Southdown had the highest percentage in 6 out of 12 and might therefore be said to have had the most preferred muscle distribution. For most muscles examined, the percentage was slightly higher for females than for males, with totals for all 12 muscles of 41·9 and 40·4% respectively.

Supplementation of high fecundity Border Leicester x Merino ewes with a high protein feed: its effect on lamb survival

1996 ◽  
Vol 36 (2) ◽  
pp. 129 ◽  
Author(s):  
GN Hinch ◽  
JJ Lynch ◽  
JV Nolan ◽  
RA Leng ◽  
BM Bindon ◽  
...  
Keyword(s):  
Birth Weight ◽  
Litter Size ◽  
Protein Supplement ◽  
High Fecundity ◽  
Lamb Survival ◽  
Staple Strength ◽  
Protein Feed ◽  
Lamb Growth ◽  
Positive Effect ◽  
Sire Breed

Two hundred and fifty Border Leicester x Merino ewes (40% heterozygous for the Booroola Fec B gene) were used in an experiment, replicated over 2 years, to examine the effects of cottonseed meal-based supplementation on lamb survival, birth, marking and weaning weight, as well as, liveweight and fleece characteristics of ewes. From 50 to 100 days of pregnancy, half of the ewes were supplemented with 80 g/head.day. The supplemented group was then split according to litter size and, until 30 days after lambing, were offered pellets at 80, 160 and 220 g/head .day, respectively, for ewes bearing single, twin and triplet (or more) lambs. Over the 2 years, ewes averaged 2.11 lambs per parturition and supplementation significantly increased lamb survival to weaning (73 v. 58%) with no interaction with litter size. Although supplementation had a positive effect on birth weight of all but twins, the effects of supplementation on survival were independent of birth weight effects. Significant effects of year, sire breed and litter size on lamb survival and birth weight were also noted. No effects of supplementation were apparent on lamb growth while ewe age, sire breed, sex and rearing rank all significantly influenced growth rates. Ewe weights, fleece weights and staple strength were significantly influenced by year, ewe age and litter size but not by supplementation. These findings indicate the benefits to lamb survival of providing a 'bypass' protein supplement to high fecundity flocks even when ewes are grazing good quality pastures.

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