scholarly journals Impact of change in body condition score in mid-late pregnancy in ewes fed a mixed diet on lamb survival and performance

2020 ◽  
Vol 82 ◽  
pp. 211-219
Author(s):  
Sue McCoard ◽  
Shen-Yan Hea ◽  
Catherine McKenzie ◽  
Kirsty Hammond ◽  
Tim Smith

The objective of this study was to evaluate the effect that body condition score of pregnant ewes fed on turnip and swede crops during mid-late gestation had on offspring survival and performance. Data were collected from 755 multiparous mixed-age ewes carrying 1–4 fetuses. Ewes grazed a turnip crop for 1 month prior to pregnancy scanning with supplementary ryegrass/clover baleage (~75 days gestation) followed by a swede crop with supplementary Lucerne baleage for 1 month following pregnancy scanning (to ~120 days gestation). Ewe body condition score (BCS) at mating, pregnancy scanning and pre-lambing, along with lamb survival and growth rates to weaning were recorded. Lamb survival from pregnancy scanning to tailing differed by litter size (P<0.001) with lower survival in litters with 3 or more lambs compared to singles and twins which did not differ. Improving BCS from pregnancy scanning to 120 days gestation had a positive effect on lamb survival irrespective of litter size and ewe age (P<0.001). Lamb survival in ewes ≥5 years of age, irrespective of litter size, was lower (P<0.001) compared to 2 or 3–4-year-old ewes, which in turn did not differ from each other. The key finding of the study was that loss in BCS from pregnancy scanning to 120 days gestation, negatively impacted on lamb survival, especially in ewes carrying 3 or more fetuses and in ewes >5 years of age irrespective of the number of fetuses carried. Furthermore, there was high variation in BCS change observed in both early and mid-pregnancy.  

2006 ◽  
Vol 18 (2) ◽  
pp. 228
Author(s):  
F. M. Alink ◽  
J. J. Robinson ◽  
M. J. A. Mylne ◽  
P. Kenyon ◽  
R. G. Watt ◽  
...  

The naturally occurring Inverdale fecundity gene (FecXI), first identified in a Romney flock in New Zealand is located on the X-chromosome and is a point mutation of the bone morphogenetic protein-15 (BMP-15) gene. Although homozygous carriers are infertile due to abnormal development (hypoplasia) of the ovaries, heterozygotes exhibit an increase in ovulation rate and numbers of lambs born, thus making the gene a candidate for improving prolificacy of crossbred hill ewes in a stratified hill and lowground sheep industry. Heterozygous Inverdale gene-carrying crossbred (Texel � Cheviot) ewes (n = 76) and noncarrier controls (n = 18) were mated by non-carrier Texel rams at approximately 18 months of age. Ultrasound pregnancy scanning took place at approximately 70 days of gestation. Lambing records comprised litter size and birthweight data and all losses, including mummified fetuses. Regression analysis tested effects of ewe genotype, pre-mating liveweight, and body condition score on litter size. ANOVA and Kruskal-Wallis tests were used to compare genotype and litter size category effects on dam and offspring data. Mean (� SEM) litter size was 2.6 � 0.10 and 1.9 � 0.11 for FecXI carrier and noncarrier ewes (P < 0.001). Although carrier ewes had lower pre-mating liveweights (60 � 5.2 vs. 63 � 3.8 kg; P < 0.05) and body condition scores (3.1 � 0.29 vs. 3.3 � 0.24; P < 0.01) than noncarrier ewes, litter size was not affected by either factor. Ultrasound scanning was a good predictor (r2 = 0.86; P < 0.001) of the eventual lamb crop. Incidences of singletons, twins, triplets and higher multiples were 8, 38, 42 and 12%, respectively, among FecXI carrier dams. Corresponding incidences among noncarriers were 17, 78, 5, and 0%. Peri- and neonatal losses increased with litter size. Of lambs from single, twin or triplet births, losses were 20% and 6% for FecXI carrier and noncarrier ewe groups, respectively (P = 0.049). Of 32 quadruplets (mean live weight = 2.65 kg), 9 did not survive; the sole set of quintuplets (mean = 1.52 kg) also succumbed. Birth weights of lambs influenced survival (P < 0.001); among quadruplets, for example, survivors were 0.5 kg heavier than counterparts that died. Surviving triplets from FecXI carrier dams were 0.8 kg heavier than non-survivors (3.66 kg vs. 2.86 kg). Overall, in this study mortality was four times greater among lambs below 3 kg live weight than among their heavier counterparts. Consequently, further studies are needed to investigate how Inverdale gene-carrying ewes can be managed during the peri-conception period to optimize litter size, placental function, and prenatal growth for maximum lamb survival. This work was funded by HIE, ANM Group, Britbreed, Ltd., and Harbro Ltd.; F. M. A. is a Genesis Faraday Associate and is sponsored by the SAC Trust, Harbro, Ltd., and Innovis.


2016 ◽  
Vol 16 ◽  
pp. 323-328
Author(s):  
C. Johns ◽  
J. Johns ◽  
D.R. Stevens

The monitoring of a high fecundity ewe flock in the Te Anau basin demonstrates the process of improved feeding to improve lamb survival and growth to weaning. Feed budgeting was changed from traditional to tailored feed requirements based on measured ewe liveweight with wastage of 15% factored in. Feed allocation was changed from monthly to weekly increases during late pregnancy, and set stocking was delayed until the planned start of lambing. This increased late pregnancy feed allocation from 99 kg DM/ewe to 128 and 144 kg DM/ewe for twin and triplet bearing ewes, respectively. Ewe body condition score was maintained at between 3 and 3.5, with condition score loss between scanning and lambing being reduced to zero. Lamb survival and lamb liveweight gain to weaning increased in both twin and triplet bearing ewes. Pregnancy scanning increased from 200 to 222 lambs per 100 ewes, between 2007 and 2012, while lambing percentage (lambs weaned/ ewe mated) rose from 132% to 165%, with more ewes rearing lambs and rearing multiples. Lamb wastage declined from 37% in 2007 and 2008, to 25% in 2011 and 2012, though scanning percentage rose by 20%. Lamb weights increased from 27.5 to 36 kg/lamb at 100 days of age. The increase in the liveweight of lambs and ewes at weaning reduced the calculated feed requirements over summer and autumn, potentially releasing 70 to 110 kg DM/ewe to provide feed to meet the extra winter feed requirements. Keywords: ewe body condition score, feed allocation, lamb survival, lamb weaning weight


1997 ◽  
Vol 128 (4) ◽  
pp. 469-477 ◽  
Author(s):  
L. M. SIBANDA ◽  
L. R. NDLOVU ◽  
M. J. BRYANT

Individually-penned Matebele does were randomly allocated to three dietary treatments during gestation (0·66, 0·50 and 0·33 MJ ME/kg metabolic weight) and subsequently offered either 0·95 or 0·6 MJ ME/kg metabolic weight during lactation in Gwanda, south west of Zimbabwe, in 1990. The diets offered consisted of veld and lucerne hay and maize grain in proportions of 0·56, 0·24 and 0·2, respectively.Reducing the amount of energy consumed from 0·58 to 0·26 MJ ME/kg metabolic weight in the last 7 weeks of gestation resulted in does suffering a net loss in body weight (−2 kg) and body condition score, although it had no significant effect on the birth weight of single kids.Reducing feeding in the first 15 weeks of lactation from 0·95 to 0·59 MJ ME/kg metabolic body weight only had minor effects upon liveweight and body condition score change of the does and had no effect on the growth of kids. Amount of feed offered in lactation had a positive effect upon milk yield and there was a trend for yields to increase proportionally to pre-partum dietary intake. Diet had no effect upon milk composition. It was concluded that the benefits of supplementary feeding are small and may not justify the extra costs entailed in smallholder systems.


2018 ◽  
Vol 42 (6) ◽  
pp. 649-657
Author(s):  
Arpan SHARMA ◽  
Sandeep KASWAN ◽  
S. Siva KUMAR ◽  
Jaspal Singh LAMBA

1997 ◽  
Vol 48 (6) ◽  
pp. 753 ◽  
Author(s):  
D. M. McNeill ◽  
R.W. Kelly ◽  
I. H. Williams

The possibility that an increase in maternal fatness might further enhance pregnancy-induced insulin insensitivity was investigated in ewes pregnant with one fetus. After selection of fat and lean ewes, they were fed to maintain maternal energy balance throughout pregnancy. A difference in insulin sensitivity of ewes in either a medium condition [score 2·9, 0·32± 0·031 kg fat/kg fat-free empty body (FFBW), n = 7] or lean body condition (score 2·0, 0·16±0.028 kg fat/kg FFBW, n = 8) at Day 136 of pregnancy was inferred by comparing their insulin response to an injection of glucose (350 mg/kg liveweight). The ewes were slaughtered at Day 146 of pregnancy to allow fetal weight, fetal fatness, and maternal fatness to be related to the capacity of the ewe to release insulin. The fatter ewes released more insulin in response to the injection of glucose (2. 54 log area units under the insulin response curve v. 2·22 for the lean ewes, pooled s.e. = 0·092, P < 0·05), yet cleared the glucose from their blood streams at the same rate as the leaner ewes. Because the fat ewes required more insulin to remove a similar amount of exogenous glucose at a similar rate to the lean ewes, we suggest that the fat ewes were less sensitive to insulin. Further, the fetuses of the fatter ewes, while not different in total weight, had higher levels of body fat than those of the leaner ewes (29·4 v. 23·8 g/kg FFBW, pooled s.e. r = 1·32, P < 0·05). Fetal fatness was also positively correlated to the magnitude of insulin release by the ewe (r = 0·61, P < 0·05). Since glucose is the major precursor of fetal fat, these data support our contention that a reduction in maternal insulin sensitivity, brought on by an increase in maternal fatness, could partition more glucose to the fetus. If fat reserves aid lamb survival, lambs from fat ewes rather than lean ewes may have a better chance of survival, particularly in cold conditions.


1999 ◽  
Vol 50 (7) ◽  
pp. 1171 ◽  
Author(s):  
D. M. McNeill ◽  
R. W. Kelly ◽  
I. H. Williams

The effect of ewe fatness on fetal weight at term in ewes underfed in late pregnancy was tested by minimising the confounding effect of differences between fatness groups in placental weight. Twin-bearing Merino ewes in a fat (n = 9, condition score 3.8 units) or moderate (n =9, condition score 2.9) body condition were underfed to 0.6 of their requirements for energy maintenance from Day 108 to 144 of pregnancy. The fatness groups were developed over an 80-day period prior to mating by splitting a flock into 2 groups, each of similar mean liveweight and body condition score, and then enhancing the nutrient intake of one whilst restricting that of the other to maintenance levels until mating. After mating, both groups were fed similarly until Day 108 of pregnancy in an attempt to allow the development of placentas of a similar size in each. Maternal fat and protein mobilised between Day 108 and 144 of pregnancy were calculated on a per animal basis as the difference between maternal fat and protein weights at Day 108, estimated by the tritiated water dilution technique, and at Day 144, estimated by chemical analysis of fat and protein tissue following slaughter. At slaughter, the fat ewes had placentas of a size similar to those of the leaner ewes (588 v. 507 g, pooled s.e. = 50.7, P > 0.10) but produced a total weight of fetus that was 14% heavier (6646 v. 5826 g, pooled s.e. = 257.6, P < 0.05). The fat ewes also mobilised more body fat between Day 108 and 144 (3.62 v. 2.58 kg, pooled s.e. = 0.446, P < 0.10), and maintained higher levels of non-esterified fatty acids in their plasma during late pregnancy. There was no effect of ewe fatness on the extent of protein mobilisation (0.66 v. 0.62 kg, pooled s.e. = 0.623, P > 0.10) over late pregnancy. We conclude that additional maternal fat reserves can limit the extent to which fetal growth is restricted in ewes undernourished during late pregnancy.


1998 ◽  
Vol 66 (3) ◽  
pp. 667-673 ◽  
Author(s):  
P. Frutos ◽  
O. Buratovich ◽  
F. J. Giràldez ◽  
A. R. Mantecòn ◽  
I. A. Wright

AbstractThirty single-bearing Merino ewes were used to examine the effect of feeding supplement, from 91 to 140 days of gestation, on changes in chemical composition of the ewes, on the relationships with live weight and body condition score and on the foetus. Ewes grazed a perennial ryegrass pasture and were offered either no supplement or 500 g per head per day of a concentrate supplement from days 30 to 90 and (or) from days 91 to 140 of pregnancy. Maternal carcass and non-carcass components, uterine wall, foetus and placenta plus cotyledons were chemically analysed. Live weight (LW) and body condition score (BCS) on day 140 were both affected by supplementation during late pregnancy, mobilization of protein and fat being lower in animals receiving supplement. BCS accounted for more variation than LW in the carcass fat depot. Because this depot was the most important source of energy from days 91 to 140 of gestation, this suggests that BCS is a useful estimator of mobilization of maternal fat reserves during this stage of pregnancy. The ability to mobilize reserves and protect foetal growth by Merino ewes in southern Europe, where large fluctuations in grass growth rate exposes them to considerable undernutrition as pregnancy proceeds, was confirmed in this experiment. However, when the nutritional regime is extreme, supplementary feeding to the ewes is recommended, in order to make the whole system economically profitable.


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