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S N Mccutcheon - One of the best experts on this subject based on the ideXlab platform.
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evaluation of Border Leicester romney br poll dorset br and suffolk br ewes for out of season lambing
New Zealand Journal of Agricultural Research, 1993Co-Authors: S T Morris, H T Blair, W J Parker, S N MccutcheonAbstract:Abstract Three different year groups of Border Leicester × Romney (BR), Poll Dorset × BR (PBR), and Suffolk × BR (SBR) ewes were evaluated for yearling liveweight and greasy fleece weight, and for their 2– and 3–year-old lambing performance under both June– and August-lambing policies. Mating of the June-lambing ewes was induced using progesterone treatment and high ram:ewe ratios. Suffolk × BR hoggets were significantly (P < 0.01) heavier than PBR and BR ewe hoggets in May, October, and January (at about 16 months of age). Border Leicester × Romney hoggets produced significantly (P < 0.01) more greasy wool at the yearling shearing than PBR or SBR hoggets. Lambing policy did not influence the proportion of ewes lambing but there were more (P < 0.05) multiple births in August-lambing ewes. Birth weights and weaning weights of June-born lambs were lower (P < 0.001) than those of their August-born counterparts. Weight of lamb weaned per ewe joined was 22.1 kg for June-lambing ewes and 24.3 kg for August-lamb...
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Evaluation of Border Leicester × Romney (BR), Poll Dorset × BR, and Suffolk × BR ewes for out-of-season lambing
New Zealand Journal of Agricultural Research, 1993Co-Authors: S T Morris, H T Blair, W J Parker, S N MccutcheonAbstract:Abstract Three different year groups of Border Leicester × Romney (BR), Poll Dorset × BR (PBR), and Suffolk × BR (SBR) ewes were evaluated for yearling liveweight and greasy fleece weight, and for their 2– and 3–year-old lambing performance under both June– and August-lambing policies. Mating of the June-lambing ewes was induced using progesterone treatment and high ram:ewe ratios. Suffolk × BR hoggets were significantly (P < 0.01) heavier than PBR and BR ewe hoggets in May, October, and January (at about 16 months of age). Border Leicester × Romney hoggets produced significantly (P < 0.01) more greasy wool at the yearling shearing than PBR or SBR hoggets. Lambing policy did not influence the proportion of ewes lambing but there were more (P < 0.05) multiple births in August-lambing ewes. Birth weights and weaning weights of June-born lambs were lower (P < 0.001) than those of their August-born counterparts. Weight of lamb weaned per ewe joined was 22.1 kg for June-lambing ewes and 24.3 kg for August-lamb...
D O Kleemann - One of the best experts on this subject based on the ideXlab platform.
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positive effects of melatonin treatment on the reproductive performance of young Border Leicester rams mated to merino ewes in spring preliminary observations
Reproduction in Domestic Animals, 2014Co-Authors: D O Kleemann, J M Kelly, L J Arney, I L Farley, A J Tilbrook, S K WalkerAbstract:Contents Poor reproductive performance of Merino ewe flocks when mated to Border Leicester rams during spring may be due to seasonality of the Border Leicester breed. Two approaches were taken to test this assumption. Six young (12 months old) or six mixed-age (12, 24 and ≥36 months old) Border Leicester rams were either treated or not treated with melatonin implants (2 9 2 design) 6 weeks before the four groups of rams were each put with approximately 300 Merino ewes for an 8-week mating period. Implants were inserted in early September (experiment 1). The second approach was to yard or not yard ewes and mixed-age rams on several occasions during the first 3 weeks of the mating period (experiment 2). Pregnancy rate and twinning percentage were assessed by ultrasonography. In experiment 1, melatonin treatment in young rams increased (p 0.05) for ewes mated to either melatonin or non-melatonin-treated young rams (36.8% vs 40.0%, respectively), whereas melatonin significantly improved (p < 0.05) twinning rate in those ewes mated to mixed-age rams (49.1% vs 36.1%). After 6 weeks of melatonin treatment, scrotal circumference was greater (p < 0.05) in both young and mixed-aged rams than in untreated counterparts. In experiment 2, yarding of ewes and rams overnight on several occasions early in the mating period reduced (p < 0.001) pregnancy rate compared with non-yarded counterparts (89.5% vs 65.5%). Twinning rate was not affected (37.7% vs 36.1%, respectively). In summary, melatonin treatment of Border Leicester rams significantly improved flock reproductive performance in spring due to improved pregnancy rates with young rams and improved litter size with mixed-age rams.
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carcass and non carcass characteristics of suffolk sired lambs from south australian merino poll dorset x merino and Border Leicester x merino ewes
Small Ruminant Research, 1990Co-Authors: D O Kleemann, Chs Dolling, R W PonzoniAbstract:Abstract The carcass and non-carcass characteristics of 121 Suffolk-sired lambs from South Australian Merino (M), Poll Dorset X South Australian Merino (PD X M) and Border Leicester X South Australian Merino (BL X M) ewes were compared in two pen experiments (PEI 1 , PE 2 ) at Turretfield Research Centre, South Australia. When lambs were slaughtered at the same liveweight and carcass characteristics adjusted to constant carcass weight (15.6 and 15.7 kg; PE 1 and PE 2 , respectively) there were no significant differences between breeds of dam for fat depth C, or for percentages of chemical fat (ether extract), protein, moisture and ash. At constant liveweight (e.g. 36.4 kg, PE 2 ) dressing percentage was higher for BL X M and PD X M compared with M progeny (44.6 and 44.5% vs. 39.9%, respectively). Differences due to breed of dam were detected for some of the non-carcass characteristics, adjusted for slaughter weight in either PE 1 or PE 2 , but on no occasion were the differences significant in both experiments. Greasy fleece weight, measured in PE 2 only, was heavier for M compared with BL X M progeny which in turn was heavier compared with PD X M progeny (1.60, 1.29 and 1.11 kg, respectively). We concluded that differences between Suffolk-sired lambs from South Australian Merino, PD X M and BL X M ewes were small for most carcass and non-carcass characteristics when compared at the same carcass weight and slaughter weight, respectively. The relative economic merit of the breeds, therefore, is more likely to be determined by factors other than those examined in the present experiments.
S T Morris - One of the best experts on this subject based on the ideXlab platform.
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evaluation of Border Leicester romney br poll dorset br and suffolk br ewes for out of season lambing
New Zealand Journal of Agricultural Research, 1993Co-Authors: S T Morris, H T Blair, W J Parker, S N MccutcheonAbstract:Abstract Three different year groups of Border Leicester × Romney (BR), Poll Dorset × BR (PBR), and Suffolk × BR (SBR) ewes were evaluated for yearling liveweight and greasy fleece weight, and for their 2– and 3–year-old lambing performance under both June– and August-lambing policies. Mating of the June-lambing ewes was induced using progesterone treatment and high ram:ewe ratios. Suffolk × BR hoggets were significantly (P < 0.01) heavier than PBR and BR ewe hoggets in May, October, and January (at about 16 months of age). Border Leicester × Romney hoggets produced significantly (P < 0.01) more greasy wool at the yearling shearing than PBR or SBR hoggets. Lambing policy did not influence the proportion of ewes lambing but there were more (P < 0.05) multiple births in August-lambing ewes. Birth weights and weaning weights of June-born lambs were lower (P < 0.001) than those of their August-born counterparts. Weight of lamb weaned per ewe joined was 22.1 kg for June-lambing ewes and 24.3 kg for August-lamb...
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Evaluation of Border Leicester × Romney (BR), Poll Dorset × BR, and Suffolk × BR ewes for out-of-season lambing
New Zealand Journal of Agricultural Research, 1993Co-Authors: S T Morris, H T Blair, W J Parker, S N MccutcheonAbstract:Abstract Three different year groups of Border Leicester × Romney (BR), Poll Dorset × BR (PBR), and Suffolk × BR (SBR) ewes were evaluated for yearling liveweight and greasy fleece weight, and for their 2– and 3–year-old lambing performance under both June– and August-lambing policies. Mating of the June-lambing ewes was induced using progesterone treatment and high ram:ewe ratios. Suffolk × BR hoggets were significantly (P < 0.01) heavier than PBR and BR ewe hoggets in May, October, and January (at about 16 months of age). Border Leicester × Romney hoggets produced significantly (P < 0.01) more greasy wool at the yearling shearing than PBR or SBR hoggets. Lambing policy did not influence the proportion of ewes lambing but there were more (P < 0.05) multiple births in August-lambing ewes. Birth weights and weaning weights of June-born lambs were lower (P < 0.001) than those of their August-born counterparts. Weight of lamb weaned per ewe joined was 22.1 kg for June-lambing ewes and 24.3 kg for August-lamb...
M L Dudzinski - One of the best experts on this subject based on the ideXlab platform.
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Body composition of young sheep: I. Body composition in merino and Border Leicester × Merino hoggets in relation to and at common empty body weight
The Journal of Agricultural Science, 2009Co-Authors: H R Gharaybeh, W R Mcmanus, G W Arnold, M L DudzinskiAbstract:Flocks of 9-month-old Merino and Border Leicester & Merino sheep were sampled over the full range of body weights present within flocks. Six pairs of ewes and wethers of equal body weight were taken. The sheep were weighed and slaughtered after a 36 h fast. Total weights of blood, skin, head, feet, internal organs and carcasses were obtained for each animal. Each component was analysed for ash, crude protein, ether extract and total energy. Half of each carcass was dissected into bone, muscle, fat and waste. The compositions of the sheep were compared by regression analyses of weights of body components on empty body weight (EBW) between the four groups and by means of percentages of EBW. There were highly significant linear relationships between both fresh and dry weights of body components, carcass components, and chemical components with EBW; moisture content was not related to EBW. Rates of change with EBW in weights of body components, or in amounts of ash, crude protein, ether extract and energy were the same for all groups of sheep with the exceptions of bone and skin ether extract (EE) weight. However, intercepts of regression lines frequently differed, indicating that body composition differed between groups at the same EBW. All groups had the same dry weight of blood, internal organs and muscle, weight of ether extract, and total energy in the whole body at the same EBW. Border Leicester × Merinos had lighter skins with less wool, but their carcass weights were higher than Merinos. There were other differences between breeds in the chemical composition of individual components. Wethers had heavier head + feet weights and carcass bone than had ewes. There were also some sex differences in chemical composition of body components. In general, there were fewer sex than breed differences in body composition. The breed differences cannot be explained on the basis of early and later maturing types.
S A Barwick - One of the best experts on this subject based on the ideXlab platform.
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the performance of the Border Leicester in australia
Animal Production Science, 2020Co-Authors: S A Barwick, I D Killeen, D J Brown, B R Cullis, A K Bell, M W Lollback, I M Rogan, G Caffery, L R Piper, B M BindonAbstract:Aims We examine the average performance of Border Leicester (BL) flocks that are part of LAMBPLAN, Australia’s sheep performance recording and genetic evaluation system. We also summarise outcomes from the New South Wales Department of Primary Industry’s research on BL improvement, and discuss the performance required for the BL to continue to be a pivotal part of the Australian prime lamb industry. Key results Modest gains have been recorded in the BL in growth since 2000 and faecal egg counts have reduced, suggesting improved worm resistance. The net reproductive rate has slightly improved, while inbreeding continues to increase. In work conducted by the New South Wales Department of Primary Industries, an improved BL flock, encompassing selection for multiple births and a broadening of the breed’s genetic base, had advantages over purebred BLs in many aspects of performance, including a 19.3% advantage in the net reproductive rate. Advantages in fertility were ~5%, litter size ~7% and lamb rearing ability ~5%. BL improved × Merino and (BL improved × BL) × Merino crossbred ewes also had advantages over traditional BL × Merino ewes in their joining performance when joined to Dorset rams. Conclusions Selection in the BL needs to emphasise traits in a manner consistent with their importance to commercial lamb production. Implications Embracing this selection and broadening the BL’s genetic base will assist the BL to maintain its place in the Australian lamb industry.
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genetic parameters for australian maternal and dual purpose meatsheep breeds i liveweight wool production and reproduction in Border Leicester and related types
Crop & Pasture Science, 1994Co-Authors: L D Brash, S A Barwick, N M Fogarty, Arthur R GilmourAbstract:Analyses of two separate Border Leicester data sets are reported. In the first set, genetic parameters were estimated for 14 month liveweight and greasy fleece weight from 1312 ewe and ram records representing 75 sires of the Border Leicester and Glen Vale breeds (a related genotype) using derivative-free REML procedures. The heritability estimate for liveweight was 0.24 ¦ 0.07 and greasy fleece weight was 0.17 ¦ 0-05, with the genetic correlation being -0 21 ¦ 0 -30 and phenotypic correlation 0.54 ¦ 0.02. In the second data set, reproductive performance was analysed and genetic parameters were estimated from 7395 joining records for 1604 ewes, representing 165 sires, from two Border Leicester stud flocks. Reproduction traits analysed were fertility (ewes lambing of ewes joined), litter size (lambs born per ewe lambing) and lambs born (per ewe joined). The studs differed in performance for all reproductive traits; fertility (67 v. 82%), litter size (1-27 v. 1-43) and lambs born (85 v. 117%). The estimates of heritability and repeatability respectively for ewe performance were: fertility 0.01 ¦ 0.01 and 0.05 ¦ 0 01, litter size 0.01 ¦ 0.02 and 0.05 ¦ 0.01, lambs born 0.00 ¦ 0.01 and 0.06 ¦ 0.01. Estimates of heritability for average ewe lifetime performance were 0.04% 0.05 for fertility, 0-02 ¦0.05 for litter size and 0.03 ¦ 0.05 for lambs born, based on averages of 4.6 joining and 3.5 litter size records for ewes. The genetic correlations between lambs born and its components fertility (0.96 ¦ 0.18) and litter size (0.83 ¦ 0.44) were high, with the genetic correlation between fertility and litter size being 0.65 ¦ 0.52. Implications for breeding programs for Border Leicester flocks within LAMBPLAN are discussed.
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maternal behaviour in Border Leicester glen vale Border Leicester derived and merino sheep
Australian Journal of Experimental Agriculture, 1990Co-Authors: G Alexander, D Stevens, L R Bradley, S A BarwickAbstract:Ewe and lamb behaviour in traditional Border Leicesters, Glen Vale Border Leicesters of the NSW Agriculture and Fisheries, Glen Vale x Border Leicester crosses and medium-fine-wool Merinos, all running in paddocks of 3-4.5 ha, were compared in spring 1983 at Glen Innes, N.S.W. Twenty-eight aspects of behaviour with a known or reputed influence on lamb survival, especially of multiples, were examined in undisturbed and contrived situations. The Glen Vales and their crosses were superior to the Border Leicesters and Merinos in behaviour and lamb survival, particularly behaviour concerned with the ability of ewes to keep their lambs together. The study indicates that contrived twin-care tests could form the basis of a selection program to improve maternal care and survival of multiples.
