INFLUENCE OF RESHEARING JUST PRIOR TO BREEDING ON REPRODUCTIVE PERFORMANCE OF A SOUTHDOWN FLOCK SELECTED FOR DATE OF BIRTH

1973 ◽  
Vol 53 (3) ◽  
pp. 399-403
Author(s):  
F. A. THRIFT ◽  
R. H. DUTT
Keyword(s):  
Statistical Model ◽  
Breeding Season ◽  
Reproductive Performance ◽  
Significant Source ◽  
Breeding Period ◽  
Sources Of Variation ◽  
Treatment Interaction

Data involving 130 ewe-yr observations were collected over a 2-yr period from a flock of purebred Southdown sheep that had closed to outside breeding since 1957 and selected for date of birth. Three treatments were imposed on the flock just prior to the breeding season: (1) rams unsheared, ewes unsheared; (2) rams sheared, ewes unsheared; and (3) rams sheared, ewes sheared. All ewes and rams were shorn each year during the 2nd wk of May. The ewes and rams were reshorn according to treatment each year on 28 July and a 120-day breeding period began immediately thereafter. The ewe traits studied were date of first estrus, date of conception, lambing date, lambs born per ewe lambing, and lambs reared per ewe lambing. The data were analyzed using a statistical model that included year, treatment, year by treatment interaction, and sire within year and treatment. Year, treatment, and the year by treatment interaction were all nonsignificant sources of variation influencing the various traits. However, sire to which the ewes were bred was a significant source of variation for date of first estrus, date of conception, lambing date, and lambs born per ewe lambing, but was nonsignificant for lambs reared per ewe lambing.

scholarly journals Effects of management system on beef heifer growth and reproductive performance

2020 ◽  
Author(s):  
Parker A Henley ◽  
Frank A Ireland ◽  
Igor F Canisso ◽  
J Lannett Edwards ◽  
Daniel W Shike
Keyword(s):  
Development Strategy ◽  
Breeding Season ◽  
Reproductive Performance ◽  
Body Condition Score ◽  
Pregnancy Rates ◽  
Fescue Toxicosis ◽  
Soybean Hulls ◽  
Randomized Design ◽  
Condition Score ◽  
Calf Performance

Abstract This study evaluated the effect of heifer development system on body weight (BW), body condition score (BCS), fescue toxicosis symptoms, reproductive performance, and subsequent calf growth of fall-calving beef heifers. Angus × Simmental heifers [n = 399; 240 ± 20.0 kg initial BW; age = 252 ± 20 d] were stratified by BW and BCS and assigned to 1 of 12 groups in each of the 2 production years. The study utilized a stratified randomized design. Pens were randomly assigned to 4 treatments: drylot (DL) development (fed ad-libitum diet consisting of 90% hay and 10% DDGS on a dry matter basis), grazing endophyte-infected fescue supplemented daily (2.3 kg as-fed/heifer/d; 50:50 mix of soybean hulls and DDGS; E+/S), grazing endophyte-infected fescue and supplemented from the midpoint of treatment period until breeding (4.5 kg as-fed/heifer/d; 50:50 mix of soybean hulls and DDGS; E+/LS), and grazing novel endophyte-infected fescue with no supplement (NE+/NS). Treatments ceased on d 168 [time of artificial insemination (AI)] and heifers were commingled and managed as a group through second breeding season. Heifers in DL had greatest (P ≤ 0.05) BW and BCS from d 28 until d 254. Furthermore, E+/S heifers had greater (P ≤ 0.05) BW and BCS than both E+/LS and NE+/NS from d 28 until d 168. On d 56 and 84, E+/LS heifers had lower (P ≤ 0.05) BW and BCS compared to NE+/NS, but on d 148 treatments reranked and E+/LS remained at a greater (P ≤ 0.05) BW and BCS compared to NE+/NS through the first breeding season. Drylot heifers had greatest (P ≤ 0.05) percentage cycling and percentage of mature BW at AI (66.6%) and had greater (P ≤ 0.05) AI and overall pregnancy rates compared to E+/LS and NE+/NS. The E+/S (55%) and E+/LS (53.7%) heifers were developed to a greater (P < 0.01) percentage of mature BW than NE+/NS (49.3%). A greater (P ≤ 0.02) percentage of DL and E+/S heifers were pregnant at the end of the first breeding season (89.3 and 85.1%; respectively) compared to NE+/NS (61.5%). In summary, DL heifers had the greatest BW and BCS at AI, percentage cycling, and AI pregnancy rate. However, this strategy did not result in differing overall pregnancy rates between DL, E+/S, and E+/LS and there were no differences in milk production, rebreeding reproductive performance, and calf performance between all treatments. Finally, the poorest AI and overall pregnancy rates of the NE+/NS heifers suggests this is not a viable development strategy for fall-born heifers.

scholarly journals Female song in the Cyprus Wheatear Oenanthe cypriaca

2021 ◽  
Author(s):  
Robert Patchett ◽  
Alexander N. G. Kirschel ◽  
Joanna Robins King ◽  
Patrick Styles ◽  
Will Cresswell
Keyword(s):  
Breeding Season ◽  
Bird Species ◽  
Breeding Period ◽  
Territorial Defence ◽  
Multiple Functions ◽  
Male Song ◽  
Female Song ◽  
Mate Acquisition

AbstractFemale song is widespread across bird species yet rarely reported. Here, we report the first observations and description of female song in the Cyprus Wheatear Oenanthe cypriaca and compare it to male song through the breeding season. Twenty-five percent of colour-ringed females were observed singing at least once, predominantly in April, compared to 71% of males that continued singing through the breeding period. We suggest that female song may have multiple functions in this species, but it may be especially important in territorial defence and mate acquisition.

Associations between early lactation milk protein concentrations and the intervals to calving for Holstein cows of differing parity

2017 ◽  
Vol 57 (10) ◽  
pp. 2100 ◽  
Author(s):  
Jack Fahey ◽  
John M. Morton ◽  
Martin J. Auldist ◽  
Keith L. Macmillan
Keyword(s):  
Dairy Cows ◽  
Reproductive Performance ◽  
Milk Protein ◽  
Holstein Cows ◽  
Breeding Period ◽  
Gestation Length ◽  
Calving Interval ◽  
Early Lactation ◽  
Average Interval ◽  
Lactating Dairy Cows

High milk protein concentrations (MP%) have been positively associated with the reproductive performance of lactating dairy cows. No studies have measured the effects of this association on subsequent calving dates in multiparous cows, nor assessed whether the underlying causal mechanisms are present in nulliparous heifers. Holstein cows (primiparous = 918; multiparous = 4242) were selected from herds that had seasonally concentrated calving patterns resulting from seasonally restricted breeding periods. In seasonally calving herds, the date of a herd’s planned start of calving (PSC date) is the average gestation length of 282 days after the date that the preceding breeding period commenced, so that the interval from the herd’s PSC date to each cow’s actual calving date (PSC-to-calving interval) primarily reflects the time to conception from the start of the breeding period in the previous year. This measure was used to compare associations between the average MP% during the first 120 days of lactation and time to the calving that initiated that lactation in primiparous and multiparous cows. Early lactation MP% was negatively associated with PSC-to-calving interval. A 1% difference in MP% was associated with an 8-day difference in the average PSC-to-calving interval in primiparous cows and a 31–35-day difference in the average interval in multiparous cows. The observed associations between early lactation MP% and PSC-to-calving interval are likely to involve determinants present during a cow’s breeding period that affect the probability of conception. Some of these determinants are not restricted to early lactation as the association between MP% and PSC-to-calving interval in primiparous cows is a reflection of the reproductive performance in nulliparous heifers at ~15 months of age.

scholarly journals Linking oceanographic conditions, migratory schedules and foraging behaviour during the non‐breeding season to reproductive performance in a long‐lived seabird

2018 ◽  
Vol 32 (8) ◽  
pp. 2040-2053 ◽  
Author(s):  
Marine Desprez ◽  
Stéphanie Jenouvrier ◽  
Christophe Barbraud ◽  
Karine Delord ◽  
Henri Weimerskirch
Keyword(s):  
Breeding Season ◽  
Reproductive Performance ◽  
Foraging Behaviour ◽  
Oceanographic Conditions

scholarly journals Sources of Variation in Survival of Breeding Female Wood Ducks

The Condor ◽  
2006 ◽  
Vol 108 (1) ◽  
pp. 201-210 ◽  
Author(s):  
Kevin M. Hartke ◽  
James B. Grand ◽  
Gary R. Hepp ◽  
Travis H. Folk
Keyword(s):  
Body Condition ◽  
Weight Of Evidence ◽  
Breeding Cycle ◽  
Breeding Period ◽  
Information Theoretic ◽  
Wood Ducks ◽  
Daily Survival ◽  
Radio Transmitters ◽  
Sources Of Variation ◽  
Nest Initiation

Abstract In waterfowl, reproduction is physiologically demanding and females are exposed to varying risks of mortality at different periods of the breeding cycle. Moreover, differences among females may influence survival within breeding periods. We captured and fitted female Wood Ducks (Aix sponsa) with radio-transmitters before nest initiation during two breeding seasons to estimate survival and investigate sources of variation in survival. We partitioned the breeding season into three periods (preincubation, incubation, postnesting) according to breeding status of individual females, and used information-theoretic methods to compare models in which daily survival varied among periods, between successful and failed nesting females, and with parameters describing individual heterogeneity. Our analysis suggested that daily survival was best modeled as a function of breeding period, differences between successful and failed nesting females during postnesting, and early incubation body condition of successful females during postnesting. Model-averaged daily survival was 0.9988 (95% CL: 0.9963–0.9996) during preincubation and 1.0 during incubation. Postnesting daily survival was 1.0 for failed nesting females and 0.9948 (0.9773–0.9988) for successful females, suggesting a trade-off between current reproduction and survival. Female age, body condition at capture, nest initiation date, and brood size generally were not useful for explaining variation in survival. Only early incubation body condition was important for modeling survival of successful females during postnesting; however, weight of evidence was limited and the effect on survival was weak. Mortality was greatest for females during preincubation and for females that nested successfully. Results support the hypothesis that brood care is costly for females.

scholarly journals Multi-Farm Analyses Indicate a Novel Boar Pheromone Improves Sow Reproductive Performance

Animals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 37
Author(s):  
John McGlone ◽  
Arlene Garcia ◽  
Anoosh Rakhshandeh
Keyword(s):  
Reproductive Success ◽  
Reproductive Performance ◽  
Cost Effective ◽  
Experimental Unit ◽  
Commercial Farm ◽  
Treatment Interaction ◽  
And Performance ◽  
Meta Analyses

The objective of this study was to examine the effectiveness of a novel 3-molecule boar pheromone (BOARBETTER®, BB,) to improve sow reproductive performance (breeding, conception, farrowing rates, pigs born alive, stillborn, mummies and total born). Data from 12 commercial farm sites were used to evaluate the effectiveness of BB. Each farm was used as the experimental unit in the meta-analyses. Individual sows records were collected, merged and analyzed in overall analyses. Relative to CON, BB increased the number of total born pigs per litter (13.81 ± 0.11 vs. 14.30 ± 0.11 pigs/litter, respectively; p < 0.01) and the number of pigs born alive (12.76 ± 0.14 vs. 13.13 ± 0.14 pigs/litter, respectively; p < 0.05). In the merged dataset analyses, the parity by treatment interaction was significant for total pigs and pigs born alive per litter (p < 0.01). In parities one through three, treatment with BB increased total pigs born by 0.88 per litter, and pigs born alive per litter by 0.73 pigs per litter (p < 0.05). However, BB had no effect on these parameters in sows from parities four through six. BOARBETTER® increased reproductive success, is cost effective, safe, and can meaningfully improve sow reproductive success and performance.

Reproductive performance of scottish blackface gimmers trained to eat supplements as ewe hoggs and offered feedblocks during mating

1986 ◽  
Vol 1986 ◽  
pp. 54-54
Author(s):  
A. Waterhouse
Keyword(s):  
Breeding Season ◽  
Reproductive Performance ◽  
Supplementary Feed ◽  
The Hill

Hill gimmers typically perform below the flock average and are reluctant to take supplementary feed. This paper reports an attempt to evaluate the effects in the first breeding season of training young flock replacements to eat supplementary feed in the form of either concentrate pellets or feedblocks.Four hundred and fifty-five ewe hoggs were allocated to two groups on return from away-wintering on 1 April. Untrained hoggs (U) were put to the hill immediately. The remainder were trained to feed (T) for one week before rejoining their contempories. Training and subsequent mating treatments are summarised in Table 1.

Breeding Australian crossbred ewes with Arabian fat-tailed rams for intensive lamb production

1996 ◽  
Vol 36 (1) ◽  
pp. 31
Author(s):  
RC Malik ◽  
MA Razzaque ◽  
S Abbas ◽  
T Al-Mutawa ◽  
N Al-Khozam
Keyword(s):  
Birth Weight ◽  
Litter Size ◽  
Reproductive Performance ◽  
Average Daily Gain ◽  
Survival Rates ◽  
Intensive Management ◽  
Season Of Birth ◽  
Genetic Groups ◽  
Sources Of Variation ◽  
Daily Gain

The reproductive performance under intensive management of Border Leicester x Merino (BLM), Dorset x Merino (DM), and Suffolk x Merino (SM) ewes imported from Australia, and local fat-tailed Naeemi (N) ewes mated to N rams was studied. Progeny performance for birth and weaning weights, average daily gain (ADG) and preweaning survival was also evaluated. BLM ewes showed the highest reproductive performance. They produced and weaned (at 8 weeks) significantly more lambs (P<0.05) than any of the other ewe genotypes. The reproductive performance of the BLM, N, DM and SM ewes, mated twice, 8 months apart, was 127, 85, 91 and 85 respectively for percentage of lambs born to ewes joined, 109, 72, 77 and 70 respectively for percentage of lambs weaned to ewes joined, and 17.8, 13.5, 12.1 and 11.6 kg respectively of lamb weaned per ewe joined over the period of 13 months from the first joining until last lambs weaned. The effect of season on ewe reproduction was significant. Birth weight was not influenced by genotype or season but did change significantly with litter size. Genetic group, litter size, season of birth and birth weight were significant sources of variation in the ADG and weaning weight of the lamb. N x BLM lambs were weaned at significantly heavier weights than lambs of the remaining 3 groups. Season of birth and birth weight also significantly affected preweaning lamb survival. About 86% of the lambs born alive were weaned with little difference between genetic groups in survival rates.

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