EFFECTS OF SEASONS ON POSTPARTUM CHARACTERISTICS OF SHEEP BEING SELECTED FOR YEAR-ROUND BREEDING AND ON PUBERTY OF THEIR FEMALE PROGENY

1975 ◽  
Vol 55 (4) ◽  
pp. 487-492 ◽  
Author(s):  
J. J. DUFOUR
Keyword(s):  
Body Weight ◽  
Female Progeny ◽  
Ewe Lambs ◽  
Age At Puberty

Second and third parity crossbred ewes being selected for year-round breeding were used after fall lambing, to study the influence of seasons on postpartum characteristics. The average fall lambing date was 8 November, and weaning occurred 14 days later. The interval between weaning and first estrus was then 18.0 days. Following an average spring lambing date of 14 May and weaning again at 14 days, the postweaning interval to first estrus was 87.1 days. Of the ewes bred, 76.6% lambed after fall lambing, 12.7% less than after spring lambing (P < 0.05). Ewes at their second parity needed 0.38 more services (P < 0.05) to produce 0.23 fewer lambs (P < 0.05) than ewes at their third parity. The ewe-lambs born to the ewes lambing in the fall and in the spring were raised to study the influence of seasons of birth on puberty. The percentage reaching puberty and the average age at puberty for ewe-lambs born in the fall were 93.3% and 312.8 days, and those in the spring were 57.1% and 201.8 days. Spring-born ewe-lambs reached puberty 75 days later in the year than fall-born ewe-lambs (P < 0.01). Of the spring-born ewe-lambs, those showing puberty were significantly heavier at 140, 168 and 196 days of age than those not showing puberty, while for the fall-born ewe-lambs, no relationship could be observed between attainment of puberty and body weight.

A note on attainment of puberty of september-born early-maturing ewe lambs in relation to level of nutrition

1991 ◽  
Vol 53 (3) ◽  
pp. 407-409 ◽  
Author(s):  
F. Forcada ◽  
J. A. Abecia ◽  
L. Zarazaga
Keyword(s):  
Sexual Activity ◽  
Breeding Season ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Plasma Progesterone ◽  
Ewe Lambs ◽  
Early Maturing ◽  
Age At Puberty

The attainment of puberty in September-born early-maturing ewe lambs was studied at Zaragoza (latitude 41° 40' N). Thirty twin Salz females were allocated to two groups receiving two nutrition levels after 3 months of age: high (500 g/day lucerne hay and 500 g/day concentrate) (H) and low (500 g/ day lucerne hay) (L). Oestrus was detected daily by aproned rams. Corpora lutea were counted after oestrus and plasma progesterone levels monitored each week.In the first breeding season (January to February) the percentage of females showing sexual activity (silent emulation or oestrus and ovulation) was higher in the H compared with the L group (67 and 20%; P < 0/05). Nonpubertal oestrus before the main breeding season was detected in 67% of animals. In the main breeding season and for H and L groups respectively, percentage of females showing silent ovulation before puberty was 67 and 33% and mean age at puberty extended to 319 (s.e. 4-8) and 314 (s.e. 3·7) days. Ovulation rate at puberty was 1·73 (s.e. 0·13) and 1·33 (s.e. 0·15) respectively (P < 0·05).

THE INFLUENCE OF THE AMOUNT OF PROTEIN AND ENERGY IN THE RATION OF REPLACEMENT EWE LAMBS ON BODY WEIGHT GAINS AND WOOL PRODUCTION

1959 ◽  
Vol 39 (1) ◽  
pp. 64-70 ◽  
Author(s):  
F. Whiting ◽  
S. B. Slen ◽  
L. M. Bezeau
Keyword(s):  
Body Weight ◽  
Wheat Straw ◽  
Corn Starch ◽  
Daily Intake ◽  
Limiting Factor ◽  
Oat Hulls ◽  
Digestible Energy ◽  
Wool Production ◽  
Ewe Lambs ◽  
Weight Gains

Three experiments were carried out with replacement ewe lambs to determine the influence of feeding rations containing three levels of protein, each at two levels of digestible energy. The three levels of protein were approximately 8, 9.5, and 11 per cent in the first two experiments, and 6, 9, and 12 per cent in the third experiment.Increasing the amount of protein in the ration resulted in an increase (p <.05) in the apparent digestibility of the protein, but no change in the percentage of protein retained or in the digestibility of the dry matter and gross energy. Increasing the digestible energy content of the ration by substituting corn starch for wheat straw or oat hulls reduced (p <.05) the digestibility and retention of protein in Experiments 2 and 3, but had no effect in Experiment 1.Body weight gains and wool growth of lambs fed rations containing wheat straw or oat hulls did not increase to so great an extent as those fed corn starch. This would indicate that energy was a limiting factor for maximum production in the lower digestible energy rations. In general, weight gains and wool production increased (p <.05) when the daily intake of D.C.P. was increased from approximately 0.10 to 0.13 pounds. Increasing the D.C.P. from 0.13 to 0.16 pounds (0.19 in Experiment 3) caused no further increase in body gains but increased (p <.05) wool production.On the basis of these results, the average D.C.P. requirements of a ewe lamb weighing 85 pounds and consuming 1.3 pounds T.D.N. was 0.13 pounds (0.16 pounds when wool production was considered).

The influence of birth type and sex on rearing of Polish Heath and Żelaźnieńska lambs

2020 ◽  
Vol 16 (4, Accepted for print) ◽  
pp. 9-20
Author(s):  
Aurelia Radzik-Rant ◽  
Witold Rant ◽  
Adrianna Bryjak ◽  
Roman Niżnikowski
Keyword(s):  
Body Weight ◽  
Ewe Lambs ◽  
Ram Lambs ◽  
Birth Type

<b>The aim of the study was to determine the effect of birth type and sex on lambs survival parameters of polish heath and żelazneńska sheep. The research included data, which was used to determine the prolificacy index, the percentage of live-born lambs and the lambs rearing index up to 100 days of age. A higher prolificacy index (P≤0.01) and a higher percentage (P≤0.01) of reared lambs were determined in the polish heath compared to the żelazneńska sheep. In the herd of the first breed, a greater proportion of twin and more numerous litters than singleton births were noted. Single and twin litters were dominant in the żelazneńskie sheep. The rearing rate of lambs from single litters was at a similar level in both observed breeds. However, in the herd of polish heath sheep, lambs from multiple litters shoved also high rearing rate. Single ram lambs were characterized by higher (P≤0.01) body weight at birth and at 56 days of age compared to twin born and ewe lambs, both in polish heath sheep and żelazneńska sheep. Statistical differences (P≤0.01) in body weight at birth and on 56th day of age were also recorded between twins and triplets in polish heath sheep. The analysis of the distribution of lambs' mortality during the rearing period has shown that the most critical is the first week of life of the born offsprings.</b>

Effects of shearing and prebreeding ram exposure on days to first mark and pregnancy rate of ewe lambs

1991 ◽  
Vol 71 (3) ◽  
pp. 905-907
Author(s):  
R. A. Kemp ◽  
S. F. Lane ◽  
Y. M. Berger
Keyword(s):  
Growth Rate ◽  
Key Words ◽  
Pregnancy Rate ◽  
Ewe Lambs ◽  
Age At Puberty

Crossbred ewe lambs were used to examine effects of shearing and prebreeding ram exposure on age at puberty and pregnancy rate. Shearing did not significantly affect age at puberty or growth rate of ewe lambs. Prebreeding ram exposure and/or shearing did not influence pregnancy rate. Key words: Shearing, ram exposure, pregnancy rate, growth

Effect of body weight on the attainment of puberty and reproductive performance of Galway and Fingalway female lambs

1979 ◽  
Vol 28 (3) ◽  
pp. 297-307 ◽  
Author(s):  
J. F. Quirke
Keyword(s):  
Body Weight ◽  
Breeding Season ◽  
Litter Size ◽  
Conception Rate ◽  
Restricted Feeding ◽  
Ewe Lambs ◽  
Younger Age ◽  
Body Weights ◽  
The Mean ◽  
Ad Libitum

ABSTRACTGroups of spring-born Galway (G) and Fingalway (F) ewe lambs were fed a concentrate diet either ad libitum (H) or at a restricted level (L) during the period 25 July to 16 October 1974 in order to induce differences in body weight at the start of the breeding season. The mean live weights of the GL, GH, FL and FH groups on 16 October 1974 were 37·8 ± 1·3, 44·6 ± 1·3, 35·1 ± 1·1 and 41·9 ± 1·2 kg respectively. More than 95% of the lambs in all four groups attained puberty before 28 February 1975. Galway ewe lambs reached puberty later in the breeding season and were older and heavier at puberty than Fingalways. Animals fed ad libitum were heavier at puberty and attained puberty earlier in the season and at a younger age than those on the restricted feeding regime.Both conception rate and litter size were lower in Galways than Fingalways. There was no evidence of any effect of the nutritional treatments on conception rate or litter size. The mean body weights at puberty for ewes which lambed and those which were barren were 41·9 ± 0·49 and 41·5 ± 0·78 kg respectively. The birth weight and growth rate of the progeny of the ewe lambs was similar for the two breeds and was not influenced by the previous nutritional treatment of the dams. The total lamb mortality between birth and weaning was 40·3%, and 72% of all deaths occurred within 48 h of birth. Losses among twins (48%) were particularly heavy.

Relation between body size and muscle fibre diameter in the newborn lamb

1956 ◽  
Vol 47 (4) ◽  
pp. 449-455 ◽  
Author(s):  
D. M. Joubert
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Muscle Fibre ◽  
Fibre Diameter ◽  
Rectus Femoris ◽  
Muscle Fibres ◽  
Muscle Fibre Size ◽  
Fibre Size ◽  
Ewe Lambs ◽  
Positive Correlations

1. An investigation is reported in which the relationship was examined between body size and muscle fibre size of nineteen newborn lambs and including twelve males and seven females. Body size was measured in terms of the dead body weight and that of the dressed carcass, while muscle fibre size was estimated on the basis of the mean crossdiameter of 150 fibres per lamb.2. It was shown that the dressing (or carcass) percentage tends to increase with an increase in body weight, from 42·26% at a body weight of 2000 g. to 49·04% at 7000 g.3. Of the 2850 cross-diameters recorded, the majority (33·8%) of the fibres measured between 8·0 and 9·6 μ, while individual fibres varied in size from 1·6 to 22·4 μ.4. Highly significant, positive correlations were shown to exist between both body (r = 0·996) and carcass (r = 0·946) weight, and mean muscle fibre diameter, indicating that differences in size between the lambs may be accounted for largely by corresponding variations in the size of individual muscle fibres.5. Of the three muscles sampled m. gastrocnemius had the largest mean fibre diameter (10·38μ), followed in decreasing order by m. rectus femoris (9·72 μ) and m. longissimus dorsi (9·09 μ). These inter-muscle differences were significant at the 1% level of probability.6. Ram lambs had significantly thicker muscle fibres (10·32 μ) than ewe lambs (8·72 μ), but also weighed the heavier and produced heavier dressed carcasses. Some evidence was produced, however, in support of the theory that at comparable weights males possess thinner individual, and therefore a greater number of fibres than females.

scholarly journals Chronic Undernutrition Inhibits KNDy Neurons in Ovariectomized Ewe Lambs

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A534-A534
Author(s):  
KaLynn Harlow ◽  
Max Griesgraber ◽  
Andrew Seman ◽  
Sydney Shuping ◽  
Jeffrey Sommer ◽  
...  
Keyword(s):  
Body Weight ◽  
Critical Role ◽  
Pulse Generation ◽  
Feed Restriction ◽  
Nutritional Regulation ◽  
Gnrh Secretion ◽  
Ewe Lambs ◽  
Body Weights ◽  
Kndy Neurons ◽  
Female Sheep

Abstract Undernutrition negatively impacts reproductive success, at least in part, through a central suppression of GnRH secretion. Given that GnRH neurons are devoid of receptors for peripheral metabolic hormones such as leptin and insulin, nutritional regulation of GnRH secretion must be through afferent input. Neurons which co-express kisspeptin, neurokinin B (NKB), and dynorphin, termed KNDy neurons, are a unique population of cells in the arcuate nucleus (ARC) of the hypothalamus and are believed to play a critical role in GnRH/LH pulse generation. With our recent evidence that chronic feed restriction reduced kisspeptin and NKB in young, castrated male sheep, we hypothesized that nutrient restriction would inhibit expression of the KNDy neuron peptides kisspeptin and NKB, while increasing dynorphin expression in young, ovariectomized female sheep. Fifteen ewe lambs were ovariectomized and were fed to maintain body weight (n=7; Fed) or feed-restricted to lose 20% of pre-study body weight (FR; n=8). Blood samples were taken weekly every 12 minutes for 4.5 hours via jugular venipuncture and plasma was stored at -20°C until assessment of LH using radioimmunoassay. Body weights were recorded weekly and feed amounts were adjusted to achieve desired body weights. Following blood collection at Week 13, animals were euthanized, brain tissue was perfused with 4% paraformaldehyde, and tissue containing the hypothalamus was collected for assessment of KNDy neuropeptide mRNA abundance by in situ hybridization (RNAscope). At Week 13, the average percent change in body weight was clearly evident (Fed, 7.35 +/- 2.2% vs FR, -21.36 +/- 0.9%), and mean LH concentrations were lower in FR ewes (10.70 +/- 3.1 ng/ml) compared to Fed controls (20.98 +/- 3.8 ng/ml). Data analyzed to date for kisspeptin, NKB, and dynorphin in the ARC show that feed restriction reduced the number of kisspeptin mRNA-expressing cells (Fed, 165 +/- 25 vs FR, 9.25 +/- 6), the number of NKB mRNA-expressing cells (Fed, 141 +/- 28 vs FR, 24 +/- 5), and the number of dynorphin mRNA-expressing cells (Fed, 109 +/- 41 vs FR, 29.5 +/- 24). Together, these findings demonstrate that chronic feed restriction suppresses KNDy neurons and supports a role for these key reproductive neurons in the central mechanism governing GnRH/LH secretion during undernutrition in female sheep.

scholarly journals INTRODUKSI DAUN KERING LEGUMINOSA POHON SEBAGAI SUMBER PROTEIN DALAM PAKAN-KOMPLIT UNTUK TERNAK DOMBA DARA

2010 ◽  
Vol 25 (1) ◽  
pp. 56
Author(s):  
Ulin Nuschati ◽  
Budi Utomo ◽  
Susanto Prawirodigdo
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Pregnancy Rate ◽  
The Body ◽  
Agricultural Technology ◽  
Protein Sources ◽  
Central Java ◽  
Ewe Lambs ◽  
Negative Effect ◽  
The One

<p>An experiment was conducted to evaluate the effect of formulated complete feed containing either one of dried legume leave of leucaena (Diet1), gliricidia (Diet2), or calliandra (Diet3) for protein sources of feed on the reproduction performance of the thin tailed ewes. The experiment used 18 head of ewe lambs of about 8 months old, which were individually penned in an elevated barn belongs to The Central Java Assessment Institute for Agricultural Technology, Ungaran. Each experimental animal was randomly fed either one of the three experimental diets. In addition, the study also employed 3 bucks of the fat tailed sheep for mating the ewes. Measurements were made for dry matter (DM) consumption of feed, weight gain, first oestrus occurrence, body weight at first oestrus, and pregnancy rate of the ewes. Results showed that the ewes fed Diet 2 consumed (535.7 g DM/d) larger (P&lt;0.05) amount of feed than that receiving Diet 1 (489.7 g DM/d) or either Diet 3 (500.3g DM/d). The data exhibited that palatability of Diet2 was superior among the three experimental diets. Consistently, weight gain of ewes (37.4 g/d) and the body weight at the first oestrous occurred (17.88 kg) of ewe fed gliricidia diet (Diet2) also higher (P&lt;0.05) than that consuming Diet1 (21 g/d and 15.88 kg) or the one consumed Diet3 (20.4 g/d and 16.37 kg). However, the distinction effect of various dried legume three leaves inclusion in the diets on the pregnancy rate was not significant (66.7% versus 66.7% versus 60%, for the animals fed Diet1 versus Diet2 versus Diet3). Overall, the present study concluded that the use of dried legume three leaves for protein sources in the complete feeds for ewes did not exhibit any negative effect.</p>

scholarly journals PUBERAL DEVELOPMENT IN THE NIGERIAN DWARF SHEEP

2021 ◽  
Vol 7 (1) ◽  
pp. 63-69
Author(s):  
B. I. Orji ◽  
J. Steinbach
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Average Daily Gain ◽  
Oestrous Cycle ◽  
Ewe Lambs ◽  
Younger Age ◽  
Daily Gain ◽  
Dwarf Sheep

THE Incidence of the first behavioural oestrus (puberty) in 28 ewe lambs was investigated to determine the effect of the plane of nutrition on it. The ewes were randomly alloted and reared on two planes of nutrition: one exclusively on roughage (grazing and bay) the second roughage supplemented with concentrate at the rate of 454g a day from weaning to puberty. The ewe lambs were checked for standing heat with two vasectomised rams twice daily - mornings and evenings. The age and body weight at puberty and the average daily gain from weaning to puberty In unsupplemented ewes were 339.5 ± 7.8 days, 14.6 ± 0.9kg and 29.4 ± 4.7g respectively. The corresponding figures for the supplemented ewes were 262.0 ± 16.2 days, 16.2 ± 0.7kg and 73.0 ± 6.6g. The ewe lambs born as singles attained puberty at a younger age but lambs fed supplemented concentrate ration had a significantly higher growth rate and attained puberty at a significantly younger age and higher body weight than ewe lambs fed on roughage only. The durations of early postpuberal oestrus and oestrous cycle were 41.03 ± 2.94 hours and 18.00 ± 0.63 days respectively.

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