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 ◽  
...  

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.

2000 ◽  
Vol 70 (1) ◽  
pp. 135-145 ◽  
Author(s):  
N. M. Fogarty ◽  
D. L. Hopkins ◽  
R. van de Ven

AbstractGrowth and survival of 3673 female and cryptorchid lambs representing the range of types (second cross, first cross and Merino) produced in the Australian lamb industry are reported. The lambs were sired by a selection of Poll Dorset (D; no. = 7), Texel (T; no. = 10), Border Leicester (BL; no. = 12) and Merino (M; no. = 12) rams and born to Border Leicester × Merino (BLM) and Merino (M) dams, which resulted in six lamb genotypes (D×BLM, T×BLM, D×M, T×M, BL×M and M×M). The second cross lambs (D×BLM, T×BLM) were heavier at birth, weaning and post-weaning and had higher growth rates, than first cross lambs (D×M, T×M, BL×M), which were higher than M×M lambs (P< 0·01). For post-weaning weight (cryptorchids at 156 days) second cross lambs were 4·2 (s.e. 0·3) kg heavier than comparable sired first cross lambs, with the BL×M 2·6 (s.e. 0·5) kg lighter than other first cross types and the MxM a further 4·2 (s.e. 0·6) kg lighter. The average advantage of D over T crosses was 1·0 kg for post-weaning weight, with greater variation amongst individual sires.Lamb survival to weaning was 76% and it was affected by birth weight and birth type (P< 0·01). Sire breed had no significant effect on lamb survival, whereas lambs from BLM ewes had higher survival than those from M ewes (P< 0·01).Overall the proportion of ewes lambing was 84% with a mean litter size of 1·77. There was no difference infertility between AI (thawed frozen semen and laparoscopic insemination) and natural (single sire) mating, although the M were higher than the BLM ewes (P< 0·01). Gestation length was 2·3 days shorter (P< 0·01) for BLM than M ewes and there was no difference between D and T sire breeds. There was little effect of birth type on gestation length but it increased with birth weight within birth type categories. Between year repeatability of gestation length for ewes was 0·33 (s.e. 0·05).


2005 ◽  
Vol 56 (5) ◽  
pp. 455 ◽  
Author(s):  
N. M. Fogarty ◽  
V. M. Ingham ◽  
A. R. Gilmour ◽  
L. J. Cummins ◽  
G. M. Gaunt ◽  
...  

The study evaluated post-weaning growth, carcass characteristics, and wool production of crossbred progeny of 91 sires from more than 7 maternal breeds (including Border Leicester, East Friesian, Finnsheep, Coopworth, White Suffolk, Corriedale, and Booroola Leicester). The sires were joined to Merino and Corriedale ewes at 3 sites over 3 years with 3 link sires in common at each site and year. Post-weaning weight at an average age of 200 days of 2841 ewes and 3027 wethers was analysed using mixed model procedures. The wethers were slaughtered at an average age of 214 days and carcass weight, fat, muscle, meat colour, and ultimate pH (24 h post-slaughter) were analysed. For ewes, hogget fleece weight, yield, fibre diameter, and faecal worm egg count (FEC) were analysed. Sire breed was significant (P < 0.01), with a range of 32.8–39.0 kg for post-weaning weight, 19.1–22.8 kg for hot carcass weight, and for carcass fat levels (11.1–17.2 mm at the GR site (FatGR) and 3.4–6.5 mm at the C site, adjusted to 22 kg carcass weight), with the East Friesian cross carcasses being very lean (FatGR 11.1 mm). Sire breed was significant for eye muscle area (P < 0.01) but not for eye muscle depth, meat colour L* (brightness), or ultimate pH. Sire breed was significant (P < 0.01) for greasy and clean fleece weight (CFW), yield, and fibre diameter (FD), with ranges of 0.9 kg (CFW) and 4.6 μm (FD). Sire breed was not significant for FEC. Type of birth and rearing classification was significant for most traits. National estimated breeding values for the sires that were entered by industry breeders indicated that they covered a range of genetic merit for most traits within their respective breeds and were generally representative of the maternal genetics available in the industry. Where there were large differences between the sire mean and breed mean breeding values the effects on crossbred progeny performance would be small and not expected to affect our conclusions about the breed differences reported. The results provide lamb producers with comparative information on sire breeds for growth, carcass and wool traits. The considerable variation among individual sires within the respective breeds will be reported in later papers.


1996 ◽  
Vol 1996 ◽  
pp. 18-18
Author(s):  
O.I. Southwood ◽  
S. Hoste ◽  
T.H. Short ◽  
A.J. Mileham ◽  
D. Cuthbert-Heavens

A significant relationship between the oestrogen receptor gene (ESR) and litter size has been detected in USA populations of Large White and a synthetic comprising 50% Meishan (Rothschild et al., 1995). Animals carrying two copies of the favourable allele (B) had an extra pig born per litter than those that did not have the allele. This paper reports on results observed in a UK 50% Meishan synthetic and four UK Large White lines.Litter size data from 50% Meishan synthetic (L93) full-sib females where more than one ESR genotype was segregating. Data were analysed using a mixed model with full relationships and including the fixed effects of season of farrowing, parity, ESR genotype (AA, AB or BB) and service type (AI or natural service). Heritiability and permanent environmental effects for litter size were assumed as 0.09 and 0.11, repectively. A total of 27 full-sib families were represented and included 62 sows and 139 litter records. Hypothesis testing used the option in PEST under a mixed model (Groeneveld et al., 1991).


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 26-27
Author(s):  
Andrew P Foote ◽  
Harvey C Freetly

Abstract The objective of this study was to determine the association of insulin, glucagon, and glucagon-like peptide (GLP-1) with production traits of growing and finishing beef heifers fed a forage- (FOR) and concentrate-based (CONC) ration. This experiment was conducted over 2 years. Shortly after weaning, heifers (n = 74 and 62, for year 1 and 2, respectively) were placed on a ration containing (DM basis) 69.8% corn silage, 30% alfalfa hay, and 0.2% salt. Feed intake was measured for 84 d using Calan gates and BW were measured at 7-time points to calculate ADG using a quadratic regression of BW on time. Cattle were then transitioned to a concentrate-based finishing ration containing (DM basis) 67.8% dry-rolled corn, 20% wet distillers grains with solubles, 8% alfalfa hay, and 4.2% vitamin/mineral supplement. Blood samples were collected on day 42 of each period. Data were analyzed as a mixed model with fixed effects of sire breed, period, and the random variable of year. Hormone concentration was included as an interaction with period to determine the association of the hormones with production traits. Dry matter intake (DMI), average daily body weight gain (ADG), gain:feed (G:F), and all three hormones were greater in the CONC period (P &lt; 0.01). Insulin was negatively associated with DMI only during the CONC period (P = 0.04) and positively associated with G:F (P = 0.01). GLP-1 was positively associated with CONC DMI (P &lt; 0.01), FOR ADG (P &lt; 0.01), and positively associated with FOR G:F and negatively associated with CONC G:F (P &lt; 0.01). Glucagon was positively associated with residual feed intake (P = 0.04). While these data do not infer causality, they do indicate that more in-depth understanding of the role of gut peptide and insulin signaling in feed efficiency needs to be evaluated.


1992 ◽  
Vol 32 (1) ◽  
pp. 1 ◽  
Author(s):  
NM Fogarty ◽  
DG Hall ◽  
PJ Holst

The effect of moderate undernutrition in mid pregnancy on lamb birth weight and survival of single- and multiple-bearing ewes is reported. A total of 1220 ewes of 3 crossbred types with different fecundity, Booroola Merino x Dorset (BD), Trangie Fertility Merino x Dorset (TD) and Border Leicester x Merino (BLM), were examined over 2 years. The treatments were low (L) and high (H) nutrition at pasture for 4 weeks from about day 75 of pregnancy. Ewe liveweight of the L group at the end of the treatments was 5 kg lower in 1984 and 8 kg lower in 1985 (P<0.01) than the H group. The differences were smaller by late pregnancy and post-lambing. The L treatment increased (P<0.01) birth weight by 0.16 kg in 1984 but had little effect in 1985. Litter size had the greatest effect on birth weight (P<0.01). Ewe crossbred type and lamb sex effects were also significant (P<0.01), although they tended to be reduced for higher order births. Nutritional treatment had no effect on gestation length. Ewe liveweight at joining and weight gains before and after the treatment period significantly affected birth weight and accounted for the large difference in birth weight between years (0.7 kg). Ewe weight gain during the treatment period in mid pregnancy had no significant effect on lamb birth weight. Nutritional treatment in mid pregnancy had no effect on lamb survival. Litter size significantly affected lamb survival, although inclusion of birth weight in the model reduced the effect. Weather conditions, as measured by chill index, significantly (P<0.01) affected lamb survival in 1984 but accounted for less variation in 1985 (P<0.05). Lamb survival for ewes was ranked BLM > TD > BD. Maximum survival was achieved at birth weights of 4-5 kg from BD and TD ewes and 5-6 kg from BLM ewes. The L treatment reduced (P<0.01) ewe greasy fleece weight by 0.15 kg but did not affect staple strength. Plasma glucose concentration at the end of treatment was lower (P<0.01) for L ewes, but there was no difference between L and H ewes in late pregnancy. Glucose declined with increasing fetal number. Plasma B-hydroxybutyrate concentration was lower for the H group than for L, and also for BLM than TD and BD ewes (P<0.01).


1980 ◽  
Vol 31 (2) ◽  
pp. 417 ◽  
Author(s):  
R Barlow ◽  
GH O'Neill

First-cross calves of Simmental (S), Friesian (F), and Brahman (B) sires were compared with straight-bred calves of Hereford (H) sires over 5 years at Grafton, N.S.W. There was a total of 775 calves sired by 205 bulls with complete records of performance from conception to weaning. Analyses were conducted to determine sire breed and sire breed x environment effects, and to provide paternal half-sib estimates of heritabilities and genetic and phenotypic correlations. Various models were used to ascertain the sensitivity of genetic parameters to the removal of different sources of variation. Among females, S x H were heaviest at birth, while among males, B x H were heaviest. The regression coefficient of birth weight on gestation length was significantly greater for B x H calves than for other crosses. All crosses grew significantly faster to weaning and were significantly heavier at weaning than H x H calves. However, there were a number of significant interactions between sire breed and environmental variables for measures of pre-weaning growth. S x H and F x H calves appeared most sensitive to environmental variation, while B x H appeared least sensitive. The significance of this is discussed. Estimates of heritability for most traits were high. Values derived by using simple models were: gestation length, 0.68; birth weight, 0.56; average daily gain (ADG) to weaning, 0.47; weaning weight, 0.54; eyelid pigmentation, 0.50. Heritabilities of birth weight and ADG during the early pre-weaning period appeared most sensitive to the amount of environmental variation removed in the model. Gestation length was positively correlated with size at birth but negatively correlated with growth to weaning. There were large positive genetic correlations among various measures of size at birth, and among various measures of growth to weaning. When compared with ADG to weaning, weaning weight was more strongly correlated with birth weight, but less strongly correlated with gestation length. The results also indicated that selection for gain over a fixed time period, immediately prior to weaning, would be as efficient as direct selection for total ADG to weaning.


2014 ◽  
Vol 54 (6) ◽  
pp. 791 ◽  
Author(s):  
N. M. Fogarty ◽  
J. G. Mulholland

The lambing performance of 1179 crossbred ewes with 5540 joining records in three seasons (autumn, winter and spring) at two sites (Cowra and Wagga Wagga) was evaluated in three lamb-production systems (spring joining with autumn backup matings at both locations, with accelerated lambing at Cowra or annual autumn joining at Wagga Wagga) over 4 years. Two genotypes of ewes, Border Leicester × Merino (BLM) and Hyfer (Dorset × Merino composite), were used at both sites, with natural matings to Dorset, Suffolk or Hyfer rams. The following five traits were analysed separately at each site to evaluate ewe lambing performance: fertility, litter size, lambs born (per ewe joined), lambs weaned (per ewe joined) and weight of lamb weaned (per ewe joined). The mixed model included fixed effects for season of joining, ewe breed, ram group, ewe prejoining weight (spline) and their interactions, with ewe fitted as a random effect. The autumn (February) joinings had higher ewe fertility, litter size and overall lamb production than did joinings in spring (October and November), with winter (June) being intermediate. At the autumn joinings, the BLM ewes had higher fertility, lambs weaned and weight of lamb weaned than did the Hyfer ewes, although this was reversed at the spring joinings, causing significant season × ewe breed interactions. While litter size was larger in the autumn than in the spring for both breeds there was a much smaller seasonal effect among the Hyfer than BLM ewes. Prejoining ewe weight had a significant effect on all reproduction traits, with generally a curvilinear response with increasing weight. The interactions of weight with season × ewe breed were significant (P < 0.001) for all traits at Cowra and most traits at Wagga Wagga. Ram group was significant (P < 0.05) for most traits, with ewes joined to Hyfer rams having higher fertility than those joined to Suffolk. and with Dorset rams being intermediate. At Wagga Wagga, this was the case for spring joinings, but there was no difference between the ram groups in autumn, causing a significant ram × season interaction (P < 0.001). Ewe repeatability ranged from 0.15 to 0.25 for all traits. Using suitable breeds or genotypes, together with optimising management, could improve out-of-season lamb production.


2021 ◽  
Vol 902 (1) ◽  
pp. 012001
Author(s):  
T Nugroho ◽  
A Nurhidayati ◽  
N Widyas ◽  
S Prastowo

Abstract This study aimed to confirm the present of dam effect on weaning weight trait of Boer goat crosses. A total of 1081 weaning weight records (standardized to 77 days) from 527 does and 16 bucks were analyzed. Data were derived from Boer, Boerja F1 (Boer 3 × Jawarandu ?), and Boerja F2 (Boer 3 × Boerja F1 ?). Two statistic models namely Model 1 and Model 2 were compared using F-test for overall significance. Model 1 is Analysis of Variance (ANOVA) which consist only fixed effect as factor, while Model 2 is mixed model which includes fixed effect as factor and dam as a random effect. The fixed effects in both models are buck, doe type, parity of the dam, sex of kid, birth type, and year of observation. Results showed that buck, doe type, sex, birth type, and observation year affect significantly (P<0.05) to weaning weight, while parity had no effect (P=0.53). Based on the model’s comparison, there was a significant difference (P<0.05) between Model 1 and Model 2. Therefore, it is confirmed the present of dam effect on the weaning weight trait of Boer goat crosses in the studied population.


Author(s):  
T W Murphy ◽  
B A Freking

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 &lt; 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.


1996 ◽  
Vol 36 (2) ◽  
pp. 129 ◽  
Author(s):  
GN Hinch ◽  
JJ Lynch ◽  
JV Nolan ◽  
RA Leng ◽  
BM Bindon ◽  
...  

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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