scholarly journals Effect of Breeding Heavier Romney Ewe Lambs at Seven Months of Age on Lamb Production and Efficiency over Their First Three Breeding Seasons

Animals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3486
Author(s):  
Emmanuelle Haslin ◽  
Rene A. Corner-Thomas ◽  
Paul R. Kenyon ◽  
Emma J. Pettigrew ◽  
Rebecca E. Hickson ◽  
...  

This experiment examined the effect of breeding heavier ewe lambs on lamb production and their efficiency over their first three breeding seasons. Two groups of ewe lambs were bred at seven months of age at an average pre-breeding live weight of either 47.9 ± 0.36 kg (heavy; n = 135) or 44.9 ± 0.49 kg (control; n = 135). Ewe live weight, number of lambs born and weaned, and lamb live weight were recorded until 39 months of age, and efficiency was calculated for each ewe. Although the number and lamb weaning weight did not differ between treatments over three years, when data were pooled, heavier ewe lambs at breeding weaned a greater number of lambs over the three-year period. The total lamb weaning weight over the three-year period increased by 2% for each additional kilogram at ewe lamb breeding. Breeding heavier ewe lambs had no effect on efficiency. These results suggest that although breeding heavier ewe lambs had a positive effect on lamb production over the three-year period, it had no effect on efficiency. Before final recommendations can be made, lifetime performance and longevity to five years of age of heavier ewe lambs at breeding are required.

2010 ◽  
Vol 50 (6) ◽  
pp. 528 ◽  
Author(s):  
N. M. Schreurs ◽  
P. R. Kenyon ◽  
F. J. Mulvaney ◽  
P. C. H. Morel ◽  
D. M. West ◽  
...  

Increasing the liveweight of ewe lambs during gestation may have positive effects on lamb birthweight and weaning weight and also on ewe lamb liveweight at weaning. Specific times during the gestation period of the ewe lamb may be more responsive to improved nutrition and increases in liveweight. The objective of this work was to use a meta-analytic approach to investigate the effects of ewe lamb liveweight at mating and during pregnancy on lamb birth and weaning weights, and the ewe lamb’s liveweight at weaning. Increasing ewe lamb liveweight in early gestation and in particular before mating gave the greatest increases in the birth and weaning weight of the lambs, and also of the ewe lamb’s liveweight at weaning compared with increasing liveweight in the second and third trimester of gestation. This indicates that management practices for ewe lambs that generate higher liveweight at mating are likely to result in increased lamb survival, higher weaning percentages, greater lamb weaning weights and create rising 2-year-old ewes with better liveweight for mating in the subsequent season. Compared with ewe lambs that gave birth and reared singletons to weaning, those ewe lambs that gave birth to twins and reared twins had greater increases in lamb birthweights, lamb weaning weights and ewe lamb weights at weaning for each extra kilogram of ewe lamb liveweight during gestation. For ewe lambs, especially those that birth and rear twins, management options that increase the pre-mating weights will have the greatest response in lamb birthweight, weaning weight and liveweight of the ewe lamb itself at weaning.


1976 ◽  
Vol 16 (80) ◽  
pp. 321 ◽  
Author(s):  
R Barlow ◽  
CJ Hodges

The reproductive performance of Merino ewe lambs was examined in flocks with different selection histories for growth to weaning and net reproductive rate. These ewes were drawn from selection flocks maintained at the Agricultural Research Station, Trangie. There was evidence of a positive genetic correlation between weaning weight and reproductive performance of ewe lambs. Selection for weaning weight had a significant effect on the percentage of ewes lambing (P < 0.05). This appeared to be a function of a higher level of fertility (P <0.05) and a higher proportion of ewes mating (n.s.). The proportion of ewes apparently in oestrus during a 39 day teasing period, prior to joining, was significantly influenced by selection for weaning weight (P < 0.05). Simultaneous selection for increased net reproductive rate, weaning weight and clean fleece weight did not result in higher ewe lamb performance than that achieved by selection for increased weaning weight alone. No conclusion could be drawn from these data about the correlation between net reproductive rate and reproductive performance of ewe lambs.


1995 ◽  
Vol 61 (3) ◽  
pp. 561-564 ◽  
Author(s):  
J. B. Gaughan ◽  
R. D. A. Cameron ◽  
G. McL. Dryden ◽  
M. J. Josey

AbstractReproductive records from 1072 Large White sows (3589 litters) were used to examine the effect ofbackfat depth (Bd) and live weight (Lw) at selection on first litter and lifetime reproductive performance. The variables investigated included mating age, total piglets born, total born alive, piglet birth weight, number weaned, piglet weaning weight, weaning to remating period and number of litters produced. Using backfat depth, sows were categorized into three groups: L, 9 to 13 mm; M, 14 to 16 mm; and F, ≥17 mm. Bd had no significant effect (P > 0·05) on the measured traits for the sows grouped by fat at first parity. When lifetime reproductive data were analysed, the L group had fewer litters (P < 0·05), and weaned fewer pigs (P < 0·01) than either the M or F group. The birth weight for piglets from L sows were significantly higher (P < 0·05) than for piglets from the other groups. The data suggest that the reproductive performance of L sows is not as good as that of M or F sows.


2017 ◽  
Vol 38 (1) ◽  
pp. 391
Author(s):  
Lincoln Bremm Oliveira ◽  
Maria Da Graça Morais ◽  
Caroline Bertholini Ribeiro ◽  
Andréa Roberto Duarte Lopes Souza ◽  
Henrique Jorge Fernandes ◽  
...  

This study aimed to evaluate the growth of body components in crossbred ewe lambs fed increasing levels of dietary concentrate and to determine the optimum level of supplementation for finishing ewe production. Thirty crossbred (½ Pantaneira × ½ Texel) wool ewe lambs fed Tifton 85 hay (Cynodon spp.) and different dietary concentrate levels (20, 40, 60, and 80% DM basis) were selected for study. At the beginning of the study, six animals were slaughtered for determination of initial body composition. The remaining animals were slaughtered at approximately 48 kg live weight. The growth of body components in relation to body growth was estimated from the allometric model BC = a × (FBW)b, where BC is body component weight, a and b are growth equation parameters, and FBW is fasted body weight. Carcass, muscle, bone, and gastrointestinal tract were late maturing (b < 1, P < 0.01). Carcass and carcass fat growth was positively affected (linear, P < 0.05) by concentrate level. Total fat weight increased with increasing concentrate level (P < 0.05). The addition of up to 60% concentrate in growing ewe lamb diets is recommended for production of carcasses with early deposition of muscle and fat. The addition of 20% concentrate in ewe lab diets is sufficient for production of carcasses with maximum deposition of muscle and no excess fat.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 483-484
Author(s):  
Tumen Wuliji ◽  
Christopher Baughman ◽  
Raquel V Lourencon ◽  
Jessica Epple-Farmer ◽  
Eric G Groose ◽  
...  

Abstract Application of ultrasound carcass trait scanning in meat animals enhances the selection efficiency and accuracy. One hundred and sixty-two mixed age Katahdin ewes were selected based on ultrasound carcass traits and bred in a high lean muscle selection (n=81) and control (n=81) flocks, respectively in December 2019. Carcass traits including loin eye area (LEA), loin eye muscle width (LEW) and depth (LED), and back-fat depth (BFD) were measured for sires, dams, and their progeny lambs. Birth weight (BW), rearing rank, sex, and weaning weight (WW=90 d) and post weaning weight (PW=120 d) were recorded for progeny. Post-weaning live weight, LEA and BFD values were calculated for deriving an expected progeny difference lists and ewe replacements. Retaining ram lambs (25% male progeny) were recorded for live weight, carcass trait scanning, and breeding values estimate at six-month old as breeding sires. There was no difference between selection and control progeny for WW, PW, BFD and LEA measurements. Means for BW, WW, PW, LEA, LEW, LED, and FBD in progeny were 3.77 ±0.56, 22.13 ±2.98, 24.48 ±3.08 kg, 5.9 ±0.1cm², 4.4 ±0.5 cm, 1.9 ±0.2 cm and 2.9 ±2.6 mm. However, the WW, PW, LEA, and LEW were measured significantly (P &lt; 0.05) greater for ram lambs (20.6 kg, 25.5 kg, 6.1 cm², 4.5 cm) over ewe lambs (19.5 kg, 23.8 kg, 5.7 cm², 4.3 cm). Single born lambs were significantly (P &lt; 0.01) heavier at birth, weaning and post-weaning, and measured greater value for LEA and LED than twin birth or reared lambs. The statistical analysis showed WW was significantly (P &lt; 0.01) correlated with PW (r=0.71) and both WW and PW correlated with LEA (r=0.5) but not with BFD. The result indicates that lean animal selection using ultrasound carcass trait scanning will improve early age selection efficiency and accuracy.


Animals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1132
Author(s):  
Sarah Schwarzkopf ◽  
Asako Kinoshita ◽  
Jeannette Kluess ◽  
Susanne Kersten ◽  
Ulrich Meyer ◽  
...  

Development of calves depends on prenatal and postnatal conditions. Primiparous cows were still maturing during pregnancy, which can lead to negative intrauterine conditions and affect the calf’s metabolism. It is hypothesized that weaning calves at higher maturity has positive effects due to reduced metabolic stress. We aimed to evaluate effects of mothers’ parity and calves’ weaning age on growth performance and blood metabolites. Fifty-nine female Holstein calves (38.8 ± 5.3 kg birth weight, about 8 days old) were used in a 2 × 2 factorial experiment with factors weaning age (7 vs. 17 weeks) and parity of mother (primiparous vs. multiparous cows). Calves were randomly assigned one of these four groups. Live weight, live weight gain and morphometry increased over time and were greater in calves weaned later. Metabolic indicators except total protein were interactively affected by time and weaning age. Leptin remained low in early-weaned calves born to primiparous cows, while it increased in the other groups. The results suggest that weaning more mature calves has a positive effect on body growth, and calves born to primiparous cows particularly benefit from this weaning regimen. It also enables a smooth transition from liquid to solid feed, which might reduce the associated stress of weaning.


1999 ◽  
Vol 69 (1) ◽  
pp. 81-92 ◽  
Author(s):  
A. F. Carson ◽  
B. W. Moss ◽  
R. W. J. Steen ◽  
D. J. Kilpatrick

AbstractThis study investigated the effects of the percentage of Texel or Rouge de l’Ouest (Rouge) genes in lambs (0, 50, 75 or 100%; the remainder being Greyface (Border Leicester × Scottish Blackface)) on lamb carcass characteristics and meat quality. Ewe lambs were slaughtered at 34, 40, 46 and 52 kg and ram lambs were slaughtered at 40, 46, 52 and 58 kg live weight. Dressing proportion increased (P < 0·001) by 0·53 and 0·27 g carcass weight per kg live weight for each 1% increase in Texel or Rouge genes respectively. Carcass conformation classification increased (P < 0·001) by 0·016 and 0·007 units (on a five-point scale) for each 1% increase in Texel or Rouge genes respectively. Carcass fat depth measures were reduced by Texel and Rouge genes such that at a constant fat depth end point, carcass weight could be increased by 0·029 and 0·023 kg for each 1% increase in Texel or Rouge genes. Carcass lean content increased (P < 0·001) by 0·99 and 0·27 g/kg for each 1% increase in Texel or Rouge genes. Subcutaneous fat content was reduced (P < 0·001) by 0·36 and 0·29 g/kg for each 1% increase in Texel or Rouge genes. Intermuscular fat content was reduced (P < 0·01) by 0·38 g/kg per 1% increase in Texel genes, whereas Rouge genes had no effect. Similarly, bone content was reduced (P < 0·01) by Texel genes only (0·31 g/kg per 1% increase in Texel genes). Warner-Bratzler shear force values showed a quadratic effect with increasing Texel and Rouge genes, with an initial decrease from 0 to 50% followed by an increase to 100%. Cooking loss increased (P = 0·05) as the percentage of Rouge genes in lambs increased. Increasing the percentage of Texel or Rouge genes significantly increased L* values (P < 0·01 and P < 0·05 respectively), b* values (P = 0·05 and P< 0·05 respectively) and H° values (P < 0·001).


Author(s):  
Imēne Ben Salem ◽  
Mourad Rekik ◽  
Mohammed Ben Hamouda ◽  
Narjess Lassoued

The current study assessed the effect of the pattern of live weight change on the ovarian function of maiden Barbarine ewes at approximately 1 year of age. For this purpose, a total of 171 weaned ewe lambs (mean live weight  ± s.d. 34.7±3.07 kg and mean age ± SD 196±10 days at weaning) were selected for the experiment. Adjustment of live weight variation  was used. Based on the slope of the curve, animals were grouped into three classes LWCI (n=46),  LWCII (n=91) and LWCIII (n=34) with live weight loss being highest in LWCI and lowest in LWCIII.  Following laparoscopy at 13 months of age, the proportion of ewe lambs found cycling in LWCIII  (85.3%) was higher in comparison to animals in LWCI (43.4%; P<0.001) and tended to be superior to those in LWCII (61.5%; P<0.05). Following synchronisation with progestagen of the females found cycling, levels of plasma IGF-I concentrations between 6 and 42 hrs after removal of sponges were not significantly different between the three classes of live weight, and respectively averaged 94.2, 90.8 and 89.8 µg/l for LWCI, LWCII and LWCIII females. Levels of estradiol were also not significantly different between the three groups (0.73, 0.70 and 0.67 pg/ml for LWCI, LWCII and LWCIII ewe lambs, respectively). It was concluded that, in low input systems of semi-arid and arid Tunisia, mating ewe lambs at the approximate age of 1 year is likely to lead to depressed reproductive performance particularly when the summer live weight-loss is elevated. 


2000 ◽  
Vol 9 (3) ◽  
pp. 187-200 ◽  
Author(s):  
R. SORMUNEN-CRISTIAN ◽  
L. JAUHIAINEN
Keyword(s):  

The effect of different feeding levels on the performance of primiparous ewes was studied in 31 Finnish Landrace ewes bred to lamb at the age of one year. Ewe lambs, initially weighing on average 19.2 kg (SEM 0.63), were placed on a low (L), standard (S) or high (H) level of feeding from 2 months of age to the end of mating and from 2 months pre-partum to the end of 8-week lactation. Changes in live weight were affected by the diet. During rearing, the ewe lambs on L diet gained significantly less (18.0 vs. 24.1 kg/lamb, P


Author(s):  
Elena Sergeevna Volobueva ◽  
Anna Nikolaevna Gneush ◽  
Maria Vladimirovna Aniskina ◽  
Alexander Ivanovich Petenko ◽  
Natalya Alexandrovna Yurina ◽  
...  

The effectiveness of the application of functional feed additives, in particular biological products, in the cultivation of poultry is shown. We have developed functional biological products No. 1 and No. 2 based on perlite and propionic acid microorganisms and azotobacter bacteria, and studying their effect on the change in growth rate and preservation of young quails for fattening at a dose of 2.0% by weight of feed. According to the results of the experiment, it was established that the best result compared with the control was provided by the additive (No. 1) based on propionic acid microorganisms and perlite (an increase in the average daily increase in live weight of quails by 21.0%). The use of bioproduct number 2 provided the growth rate of poultry, in comparison with the control, by 20.2% Also, feeding of symbiotic supplement No. 2 in the amount of 2.0% ensured 100% survival of young poultry, and supplements based on propionic acid microorganisms and perlite — 98.0%, which is 6.0 and 4.0% higher than the benchmark. The results show that both bioproducts have a positive effect on the growth and preservation of quails and are recommended as supplements to the complete feed throughout the fattening period.


Sign in / Sign up

Export Citation Format

Share Document