REPRODUCTIVE PERFORMANCE OF ROMANOV EWE LAMBS HAVING CONCEIVED AT THREE MONTHS OF AGE

1990 ◽  
Vol 70 (2) ◽  
pp. 715-717 ◽  
Author(s):  
M. H. FAHMY
Keyword(s):  
Body Weight ◽  
Key Words ◽  
Litter Size ◽  
Reproductive Performance ◽  
Ewe Lambs ◽  
Ram Lambs

Of 19 Romanov ewe lambs exposed to ram lambs up to 90 d of age, 11 lambed at 233 ± 2.8 d of age and 39.2 ± 0.74 kg body weight. They lambed 1.54 and weaned 1.18 lambs. Of these 11 ewes, 73% lambed again at 16 mo compared to 100% for less precocious ewes. Litter size was 2.50 and 3.25 at birth and 2.00 and 2.38 lambs at 70 d for the two groups, respectively. By 16 mo of age, both groups of ewes weighed about 53 kg, the ewes which lambed twice produced slightly more lambs; however, the weight of lambs produced at 70 d was similar in both groups (53.5 vs. 52.6 kg). Key words: Puberty, Romanov, reproductive performance

THE ACCUMULATIVE EFFECT OF FINNSHEEP BREEDING IN CROSSBREEDING SCHEMES: REPRODUCTIVE PERFORMANCE

1988 ◽  
Vol 68 (1) ◽  
pp. 69-81 ◽  
Author(s):  
MOHAMED H. FAHMY ◽  
JACQUES J. DUFOUR
Keyword(s):  
Body Weight ◽  
Mortality Rate ◽  
Key Words ◽  
Litter Size ◽  
Reproductive Performance ◽  
Conception Rate ◽  
Ovulation Rate ◽  
Genetic Groups ◽  
Linear Regressions ◽  
Size At Birth

Reproductive performance and body weight were studied on 361 ewes, representing Finnsheep (F), DLS (a population of 1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) and seven combinations ranging from 1/8 to 7/8 Finnsheep breeding. Conception rate in yearlings was 61.5% for DLS compared to 89.0% for F with the crosses being intermediate. Conception rate in older ewes was similar in the different genetic groups (avg. 94%). Ovulation rate and litter size at birth of DLS ewes were 1.72 and 1.44 lambs, which was less than half those of F ewes (3.51 and 2.86 lambs, respectively). Both traits increased progressively with an increase in F breeding in crosses and with advances in age. DLS ewes weaned 1.22 lambs compared to 2.03 lambs for F ewes and 1.84 lambs for 4/8 F ewes. The heaviest litters at weaning (31.7 kg) were raised by 4/8 F ewes, followed by 7/8 F (30.8 kg) while those raised by DLS ewes weighed 23.0 kg and F ewes 29.1 kg. Percentage of ova lost per ewe mated averaged 24% and ranged between 18% (DLS and 1/8 F) and 29% (6/8 F). About 3.6% of lambs were born dead and a further 13.8% died before weaning. Preweaning mortality rate was highest in F (22.9%) and lowest in 3/8 F (9.4%). Average kilograms of lambs weaned per ewe exposed was highest in 4/8 F (27.6 kg) followed by F (26.0 kg), whereas that of DLS was the lowest at 18.1 kg. The 4/8 F cross showed 25% heterosis in kg of lambs weaned per ewe exposed and 52.5% increase over DLS. Significant positive linear regressions were calculated for ovulation rate, litter size and preweaning mortality rate on proportion of Finnsheep breeding in crosses. The relation was quadratic for percent ova lost and lamb mortality at weaning. Yearling DLS females weighted 36 kg compared to 44 kg for F yearlings. However, at 5 yr of age DLS ewes weighed 62 kg, 5 kg heavier than F ewes. The heaviest ewes at all ages were the 4/8 F (45 kg at 1 yr, 65 kg at 5 yr). Key words: Reproduction, DLS sheep, Finnsheep, crossbreeding, heterosis, repeatabilities

scholarly journals The influence of adding estradiol to semen on reproductive performance of sows

1991 ◽  
Vol 71 (2) ◽  
pp. 589-591 ◽  
Author(s):  
R. N. Kirkwood ◽  
P. A. Thacker
Keyword(s):  
Key Words ◽  
Litter Size ◽  
Reproductive Performance ◽  
Artificial Insemination ◽  
Pregnancy Rates ◽  
And Control ◽  
Estradiol 17Β

One hundred gilts and one hundred mixed-parity sows of Yorkshire and Landrace breeding were inseminated with semen with or without an additional 10 μg estradiol-17β. Pregnancy rates of gilts receiving estradiol-supplemented and control semen were 90 and 79%, respectively (P < 0.09). The estradiol supplementation of semen did not improve the pregnancy rates or litter size in sows. Key words: Swine, artificial insemination, estradiol

The influence of purified porcine relaxin on the reproductive performance of sows following artificial insemination with fresh or frozen semen

1991 ◽  
Vol 71 (1) ◽  
pp. 237-239 ◽  
Author(s):  
P. A. Thacker ◽  
A. D. Gooneratne ◽  
R. N. Kirkwood
Keyword(s):  
Key Words ◽  
Pregnancy Rate ◽  
Litter Size ◽  
Reproductive Performance ◽  
Artificial Insemination ◽  
Pregnancy Rates ◽  
Frozen Semen

Pregnancy rates and litter sizes following insemination of sows with fresh-extended and frozen-thawed semen averaged 71 vs. 53% and 10.6 vs. 4.4, respectively, and was not affected by the addition of 12.5 μg relaxin to semen. These results indicate no relaxin mediated effect on either pregnancy rate or litter size when sows are artificially inseminated with relaxin-supplemented semen. Key words: Artificial insemination, relaxin, sows

INFLUENCE OF BREED, BIRTH DATE, AGE AND BODY WEIGHT ON LINEAR BODY MEASUREMENTS OF GROWING RAMS MAINTAINED IN A CONTROLLED ENVIRONMENT

1984 ◽  
Vol 64 (2) ◽  
pp. 279-291 ◽  
Author(s):  
J. N. B. SHRESTHA ◽  
D. P. HEANEY ◽  
P. S. FISER ◽  
G. A. LANGFORD
Keyword(s):  
Body Weight ◽  
Key Words ◽  
Litter Size ◽  
Body Length ◽  
Birth Date ◽  
Controlled Environment ◽  
Body Measurements ◽  
Leg Length ◽  
The Relationship ◽  
Linear Body

Heart girth (HG), body length (BL), leg length (LL), metacarpal circumference (MC), withers height (WH) and hook width (HW) of 233 growing rams of three synthetic strains, Suffolk and Finnsheep breeds were measured at 6, 8 and 10 mo of age. Thereafter, subsequent measurements were taken at 11–13 mo, 18–21 mo and 23–25 mo of age. Breed, birth period (hysterectomy derived birth date), age of ram and body weight (BW) had important effects (P < 0.05) on linear body measurements, whereas age of dam did not (P > 0.05). Significant effects of litter size on HG and BL were observed at 6 and 8 mo of age, respectively. All linear body measurements increased from 6 to 21 mo of age, whereas BL, WH and HW continued to increase to 25 mo. Rams of Strain 1, developed as a synthetic sire strain, with a large proportion of Suffolk background were generally similar to the Suffolk rams in all body measurements except for HG which was significantly larger than in Suffolk rams. The Finnsheep rams had smaller HG, BL, MC and HW than the synthetic strains and Suffolk rams, whereas LL and WH of the Finnsheep and Suffolk rams were similar. Rams of Strains 2 and 3, developed as synthetic dam strains with 50 percent Finnsheep background, were similar in body measurements. The synthetic dam strains did not differ from Strain 1 and/or Suffolk with respect to HG, BL, WH and HW. However, Suffolk rams had larger MC and shorter LL compared to those of the Strain 2 and 3 rams. Birth period had a significant effect on HG, BL, LL and MC, but no consistent trend with age of ram was apparent. Linear body measurements were positively correlated with each other and with body weight; however, the relationship varied as rams progressed in age. The importance of breed, birth date, age of ram and body weight on body measurements and the requirements for appropriate adjustments is emphasized. Key words: Sheep, body measurements, breed, birth date, age of ram

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>

Reproductive performance over repeated parities of lines of mice selected for appetite, lean growth and fatness

1986 ◽  
Vol 42 (3) ◽  
pp. 397-410 ◽  
Author(s):  
F. D. Brien ◽  
W. G. Hill
Keyword(s):  
Body Weight ◽  
Litter Size ◽  
Lean Mass ◽  
Reproductive Performance ◽  
Late Pregnancy ◽  
Reproductive Rate ◽  
Lean Growth ◽  
Implantation Sites ◽  
Average Total Number ◽  
Post Implantation

ABSTRACTFemale reproductive performance over four parities was studied for lines of mice selected for one three criteria: appetite (A), total lean mass (P), or proportion of fat (F). Female mice were first bred 8 weeks of age, and thereafter at intervals of about 7 weeks until fourth parity when they were dissected in late pregnancy to measure components of litter size.The high A lines had higher litter sizes at the first three parities and higher ovulation rates, numbers of implantation sites and live foetuses at the fourth parity than the low A lines. The high P lines were also higher than the low P lines for each of these traits. In contrast, litter sizes and ovulation rates differed little between the high and low F lines. Fitting body weight as a covariate removed the high-low differences in ovulation rate and litter size between the P lines, but not all the differences between the A lines.Pre-implantation survival at the fourth parity was slightly lower in the high than in low A and in high than in low P lines. Differences in post-implantation survival were very small. No component of prenatal survival differed substantially at fourth parity between the high and low F lines.Differences in fertility at each parity and the percentages of females surviving to the end of the study were small. At each litter, dams of the high A lines produced heavier total weights of litters at 12 and 21 days than dams of the low A lines and the corresponding high-low differences in the P lines were larger. There were only small differences in these traits between the F lines. When litter size, fertility and survival were summed over parities, the average total number of young produced per female was substantially higher in the high than in the low A lines (5·0 young born alive or dead) and the P lines (7·2), but the high-low difference was small in the F lines (2-0). For all lines, litter size at first parity gave a reliable indication of reproductive rate during a major portion of the reproductive lifespan.

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.

scholarly journals Effect of body weight at first mating on reproductive performance of rabbit does

2020 ◽  
Vol 46 (5) ◽  
Author(s):  
O. Y. Ayo-Ajasa ◽  
L.T. Egbeyale ◽  
F. A. Adewole ◽  
D. A. Ekunseitan ◽  
O. A. Babalola
Keyword(s):  
Body Weight ◽  
Litter Size ◽  
Reproductive Performance ◽  
Reproductive Parameters ◽  
Initial Body Weight ◽  
Average Birth Weight ◽  
Statistical Representation ◽  
T1 And T2 ◽  
Breeding Efficiency ◽  
Size At Birth

Eighteen mature nulliparous rabbit does with initial body weight between 1600g-2500g were used to evaluate the effect of body weight at first mating on reproductive performance of rabbit does. These rabbits were assigned into three treatments, with T1, T2 and T3 weighing (1600-1900), (1901-2200) and (2201-2500) respectively. The study lasted for 5weeks. The does were mated with buck at ratio 1:3. The reproductive parameters evaluated were number of does that kindled, litter size at birth, breeding efficiency, litter size at weaning, pre-weaning loss. All data collected were subjected to descriptive statistical representation. The highest number of kindled does was 5 in T2 and T3; T1 had the lowest number (3). Breeding efficiency of 83.33% was recorded in T1 and T2 while T3 had 50.00%. T3 had highest average birth weight (49.51g) and T2 had the least (41.51g); litter size at birth and weaning ranged from 18 -28kits and 15-24kits, respectively. T2 does recorded highest value in both parameters, T3 does recorded same value (28kits) for litter size at birth. Highest pre-weaning loss of 7kits was recorded from does in T3 while T1 and T2 recorded 4kits. It was therefore concluded that does with weight range 1901g – 2200g had better reproductive performance with highest breeding efficiency and lower pre-weaning loss.

scholarly journals Effect of restricted feeding under rearing on reproduction, body condition and blood metabolites of rabbit does selected for growth rate

2017 ◽  
Vol 25 (4) ◽  
pp. 303 ◽  
Author(s):  
C. Naturil-Alfonso ◽  
F. Marco-Jiménez ◽  
J.J. Pascual ◽  
J.S. Vicente
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Litter Size ◽  
Body Condition ◽  
Reproductive Cycle ◽  
Reproductive Performance ◽  
Young Rabbit ◽  
Fat Thickness ◽  
Ad Libitum ◽  
Perirenal Fat

Young rabbit females selected for growth rate can have nutritional needs which may not be met by the common practice of feed restriction during rearing in commercial rabbit production. The aim of this study was to analyse the effect of two different feeding programmes: restricted and ad libitum feeding, applied in young rabbit females for one month at the end of rearing, on reproductive performance, body condition and circulating metabolic hormones and metabolites in a rabbit line selected by growth rate in 3 consecutive reproductive cycles. Thus, twenty-four 16-week-old does were randomly assigned to a group in which the daily recommended nutrient intakes were satisfied (fed restricted: 130 g/day, n=13) or a group fed to satiety (ad libitum: 235.5 g/day, n=11) during one month. Then, all does were inseminated in 3 consecutive cycles using a 42-day reproductive cycle. Measurements of does’ body weight, perirenal fat thickness and plasma leptin, non-esterified-fatty-acids (NEFA), beta-hydroxybutyrate (BOHB) and fructosamine were performed at artificial insemination (AI), parturition and weaning time in 3 consecutive cycles. Reproductive performance of does was evaluated based on fertility, litter size at parturition, prolificacy and productivity. Differences in body weight were found only in the 1<sup>st</sup> cycle, ad libitum fed females being heavier than restricted ones. Nevertheless, body weight variances disappeared in later cycles. No differences were found in perirenal fat thickness. Finally, in ad libitum fed females slight differences were found in plasma levels of NEFAs (452 vs. 258 μekv/L and 527 vs. 306 μekv/L for 1<sup>st</sup> and 2<sup>nd</sup> cycles) and BOHB (0.26 vs. 0.03 mM for 2<sup>nd</sup> cycle), but disappeared in the 3<sup>rd</sup> reproductive cycle. Fertility, prolificacy and productivity was not significantly affected by the feeding programme. Nevertheless, total litter size showed to be higher in ad libitum fed females at second parturition (8.7 vs. 5.9 kits). Therefore, the evaluated feeding programmes until first AI in females selected by growth rate had no effect on their reproductive outcomes, as the global reproductive performance was not affected.

scholarly journals Effects of selection on growth, body composition and food intake in mice: II. Correlated responses in reproduction

1984 ◽  
Vol 44 (1) ◽  
pp. 73-85 ◽  
Author(s):  
Forbes D. Brien ◽  
Gillian L. Sharp ◽  
William G. Hill ◽  
Alan Robertson
Keyword(s):  
Body Composition ◽  
Body Weight ◽  
Food Intake ◽  
Litter Size ◽  
Reproductive Performance ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Primary Reason ◽  
Correlated Responses ◽  
Fat Percentage

SummaryFemale reproductive performance is reported in mice selected for ten generations for one of three criteria: either appetite (A), fat percentage (F) or total lean mass (P). For each criterion lines were selected for high (H) or low (L) performance, with contemporary unselected controls (C). In the A and P lines, litter size changed in the direction of the selected criterion, the changes being larger and more rapidly established in the A than in the P lines. At generation 10, the differences in litter size between high and low lines were 2·6 live young born in the A lines, and 1·0 live young born in the P lines. The differences in 6-week weight between the high and low lines were 3·5 g in the A lines, 6·5 g in the P lines. Changes in ovulation rate were the primary reason for changes in litter size, the differences between the high and low lines being 3·8 corpora lutea for the A lines, and 3·1 corpora lutea for the P lines. Fitting body weight at mating as a covariate within lines in the analysis of ovulation rate and live foetus number removed the differences between the high and low selected P lines, but not those in the A lines. The high and low selected A and P lines did not differ in prenatal survival. There were no consistent differences in litter size, ovulation rate or pre-natal survival in the F lines.

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