Body condition and feather molt of a migratory shorebird during the non-breeding season

2018 ◽  
Vol 49 (4) ◽  
pp. jav-01480 ◽  
Author(s):  
Matilde Alfaro ◽  
Brett K. Sandercock ◽  
Luciano Liguori ◽  
Matias Arim
2021 ◽  
pp. 117434
Author(s):  
Hilde Karin Midthaug ◽  
Daniel J. Hitchcock ◽  
Jan Ove Bustnes ◽  
Anuschka Polder ◽  
Sébastien Descamps ◽  
...  

1977 ◽  
Vol 24 (3) ◽  
pp. 377-385 ◽  
Author(s):  
M. J. Ducker ◽  
J. S. Boyd

SUMMARYBody size was estimated for 255 Greyface ewes using five linear body dimensions. On the basis of this calculated measure combined with a subjective measure of body size 50 small and 50 large ewes were selected for use in the experiment. Precise ovulation data were obtained by endoscopy and this technique allowed the ewes to be mated subsequently.Body size did not affect the mean ovulation rate of the ewes although, at the same level of body condition, the large ewes were 25% heavier than the small ewes. The ovulation rates and the numbers of lambs born were influenced by changes in live weight and body condition. For these reasons live weight per se was not a good indicator of ovulation rate as ewe live weight was a combination of both body size and body condition. At the same live weight small ewes in improving body condition had a significantly higher ovulation rate than large ewes in reducing body condition.The onset of the breeding season of the ewes was not affected by their body size. The mean date of onset of oestrous activity for both large and small ewes was 17 October 1972 at a latitude 55° 52′ N.


2010 ◽  
Vol 22 (1) ◽  
pp. 249
Author(s):  
P. G. Rodrigues ◽  
C. M. Raymundo ◽  
M. C. M. G. Miranda ◽  
J. B. Bastos ◽  
J. C. DeSouza

The objective was to investigate the relationship between changes in body condition on reproductive traits of donor mares in an embryo collection program. Fifty-six non-pregnant mares, 3 to 18 years old, were studied from August 2008 through April 2009. Body condition score (BC; 1-9 scale, thin to obese) was estimated monthly. Body weight and tail and rib s.c. fat depths (SF) were measured monthly. SF was determined by ultrasound. Dominant follicle diameter (DF) was measured daily during the follicular phase. Mares were artificially inseminated and embryo transfers were conducted 6 d after ovulation. Analyses were performed with SAS® (SAS Institute Inc., Cary, NC, USA). Age classes were as follows: age 1, 3 to 6.9 (n = 17); age 2, 7 to 12.9 (n = 25), and age 3, ≥13 years (n = 14). Months in experiment were T1 to T6. BC classes were as follows: B1, <6.5; B2, 6.5 to 6.9; B3, 7.0 to 7.5; and B4, >7.5. Embryo recovery rate was compared by chi square. Effects of month and age on BC, weight, and SF were analyzed by a mixed model. Age, BC, and month fixed effects on DF diameter were analyzed by ANOVA with mare within class as the error term. Means were compared by contrasts. BC was higher (P = 0.02) in older mares (6.78 ± 0.2 and 6.93 ± 0.2 in age 1 and age 2 v. 7.25 ± 0.2 in age 3) and increased (P = 0.009) with time (from 6.79 ± 0.20 to 7.42 ± 0.26 for T1 to T6, respectively). Weight (kg) was not associated with age but increased (P = 0.03) throughout the experiment. Tail fat increased with age (P = 0.04) and decreased with increasing months on experiment (P = 0.02). DF diameter increased daily through the follicular phase (P < 0.0001) and was smaller (P < 0.05) in mares with lower body condition (33.80 ± 0.31 in BC1 v. 34.17 ± 0.31 mm in BC4). DF diameter decreased (P < 0.01) with month on study. Embryo recovery rate was not affected by age or BC but was lower (P = 0.003) in mares that ovulated follicles smaller than 40 mm compared to mares ovulating follicles greater than 40 mm. BC above 6.5 was associated with higher embryo recovery rate, which was, in turn, correlated positively with DF diameter. Thus, our results support the use of BC scoring to predict performance in equine embryo transfer programs. Body condition scoring was not a good indicator of SF under the current experimental conditions because SF decreased during the breeding season. BC scoring may indicate lean tissue gain, which may be a better indicator of reproductive efficiency in mares. FAPEMIG, CAPES, Haras El Far.


2019 ◽  
Vol 31 (1) ◽  
pp. 129
Author(s):  
J. B. S. Borges ◽  
D. S. V. Luiz ◽  
P. R. L. Aguiar ◽  
C. G. B. Berlitz ◽  
G. S. Velho ◽  
...  

Beef heifers that conceive early during their first breeding season calve earlier, wean heavier calves, and tend to continue doing so throughout the rest of their reproductive lives. Otherwise, under extensively managed systems in Southern Brazil, only a variable proportion of 2-year-old beef heifers reach puberty before the start of the breeding season. The aim of this study was to evaluate a protocol to induce puberty in peripubertal beef heifers using injectable progesterone (P4) and oestradiol cypionate (EC) to improve pregnancy per AI (P/AI) in fixed-time AI (FTAI) programs. A total of 311 Angus heifers, 24±3 months of age, 3.1±0.3 body condition score (1=emaciated; 5=obese), and 328±41kg of body weight (BW), were examined before FTAI protocol (Day −24) by transrectal ultrasonography to determine reproductive tract score (RTS; 1=prepubertal; 5=pubertal). Prepubertal heifers (RTS 1; 12.8%, 40/311) were excluded from the study. Heifers with RTS=2 (n=271) were assigned to 2 groups: P4 (RTS 2 or 3, n=100) and cyclic (RTS 4 and 5, n=171). Peripubertal heifers were treated on Day −24 with 150mg of injectable P4 IM (Sincrogest® injectable, Ourofino Animal Health, Cravinhos, Brazil) and on Day −12 received 1mg of EC IM (Sincro CP®, Ourofino Animal Health). Cyclic heifers received no hormonal treatment before FTAI protocol. On Day 0, heifers in the P4 group were evaluated again to determine RTS, body condition score, and BW. Induction of puberty was defined by the presence of a follicle &gt;8.5mm (RTS=4) or a corpus luteum (RTS=5). All heifers received an FTAI protocol consisting of 2mg of oestradiol benzoate IM (Sincrodiol®, Ourofino Animal Health) and an intravaginal progesterone implant (1 g; Sincrogest®, Ourofino Animal Health). On Day 8, heifers had implants removed and were injected with 1mg of EC and 500µg of sodium cloprostenol IM (Sincrocio®, Ourofino Animal Health). After 48h, all heifers received an FTAI. Thirty days after AI, the diagnosis of gestation was performed by ultrasonography. Statistics included chi-square and linear regression with coefficients analysed as independent variables, considering a significant P-value of 0.05. On Day 0, percentages of RTS 5, 4, and 3 in the P4 heifers were 37, 27, and 36%, respectively, resulting in 64% of puberty induction. The P/AI was similar (P=0.14) in P4-treated and cyclic heifers (59v. 50.3%, respectively). The regression analysis presented a linear and positive effect of BW on P/AI (P&lt;0.001) in cyclic heifers and a positive influence of BW on RTS (P=0.05) and RTS on P/AI (P=0.008) in P4-treated heifers. The application of RTS system associated with P4 treatment of peripubertal heifers before FTAI protocol improved ovarian activity and might have contributed to higher P/AI, comparable with that achieved in cyclic heifers.


2019 ◽  
Vol 30 (6) ◽  
pp. 1642-1652 ◽  
Author(s):  
Chloé Montreuil-Spencer ◽  
Kelsey Schoenemann ◽  
Ádám Z Lendvai ◽  
Frances Bonier

Abstract Reproduction is an energetically demanding life history stage that requires costly physiological and behavioral changes, yet some individuals will invest more into reproduction and breed more successfully than others. To understand variation in reproductive investment, previous studies have evaluated factors during breeding, but conditions outside of this life history stage may also play a role. Using a free-ranging population of black-capped chickadees (Poecile atricapillus), we assessed the repeatability of plastic traits relating to energetic condition (circulating initial corticosterone concentrations and body condition) during the nonbreeding season and evaluated whether these traits predicted reproductive investment in the subsequent breeding season. We found that initial corticosterone concentrations and an index of body condition, but not fat score, were moderately repeatable over a 1-week period in winter. This trait repeatability supports the interpretation that among-individual variation in these phenotypic traits could reflect an intrinsic strategy to cope with challenging conditions across life history stages. We found that females with larger fat reserves during winter laid eggs sooner and tended to spend more time incubating their eggs and feeding their offspring. In contrast, we found that females with higher residual body mass delayed breeding, after controlling for the relationship between fat score and timing of breeding. Additionally, females with higher initial corticosterone in winter laid lighter eggs. Our findings suggest that conditions experienced outside of the breeding season may be important factors explaining variation in reproductive investment.


2015 ◽  
Vol 31 (2) ◽  
pp. 235-243
Author(s):  
P. Slavova ◽  
S. Laleva ◽  
Y. Popova

?bject of the study were merino sheep raised in the farm of the Agricultural institute - Stara Zagora. The experiment was conducted with a group of 68 animals of different ages, lambing after treated with hormonal preparation according to adopted scheme during the out-of-breeding season - in May. In the experimental group were included ewes which lambed earlier without making a selection in respect to their productivity. Animals were kept under the same conditions (stall-pasture) and fed the same rations with the concentrate mixture, rough, succulent feed and grazing in quantity and composition according to their physiological status and season from the fertilization until lambing. Hormonal pattern: setting pads for sheep type Sincro-part (30mg), removing pads after 12 days and giving ewes a PMSG injection at a dose of 500 UI, applying artificial insemination at the 50-55th hour. Body condition score and live weight of the animals were determined in 4 separate periods: 1st period (after mating), 2nd period (during pregnancy), 3rd period (after lambing), 4th period (before next mating service). Improving fertility in merino sheep is significantly influenced by the preparation of ewes for the mating by reaching the respective physiological status which is expressed by score over 2.5 according to the Body condition score method and live weight over 60 kg. Animals scored 2.75-3.50 before mating have a share of 91.18% from all the sheep in the flock and have the biggest number of lambs.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Sarah F. Worsley ◽  
Charli S. Davies ◽  
Maria-Elena Mannarelli ◽  
Matthew I. Hutchings ◽  
Jan Komdeur ◽  
...  

Abstract Background The vertebrate gut microbiome (GM) can vary substantially across individuals within the same natural population. Although there is evidence linking the GM to health in captive animals, very little is known about the consequences of GM variation for host fitness in the wild. Here, we explore the relationship between faecal microbiome diversity, body condition, and survival using data from the long-term study of a discrete natural population of the Seychelles warbler (Acrocephalus sechellensis) on Cousin Island. To our knowledge, this is the first time that GM differences associated with survival have been fully characterised for a natural vertebrate species, across multiple age groups and breeding seasons. Results We identified substantial variation in GM community structure among sampled individuals, which was partially explained by breeding season (5% of the variance), and host age class (up to 1% of the variance). We also identified significant differences in GM community membership between adult birds that survived, versus those that had died by the following breeding season. Individuals that died carried increased abundances of taxa that are known to be opportunistic pathogens, including several ASVs in the genus Mycobacterium. However, there was no association between GM alpha diversity (the diversity of bacterial taxa within a sample) and survival to the next breeding season, or with individual body condition. Additionally, we found no association between GM community membership and individual body condition. Conclusions These results demonstrate that components of the vertebrate GM can be associated with host fitness in the wild. However, further research is needed to establish whether changes in bacterial abundance contribute to, or are only correlated with, differential survival; this will add to our understanding of the importance of the GM in the evolution of host species living in natural populations.


2014 ◽  
Vol 26 (5) ◽  
pp. 533-544 ◽  
Author(s):  
Andrew D. Lowther ◽  
Christian Lydersen ◽  
Martin Biuw ◽  
P.J. Nico de Bruyn ◽  
Greg J.G. Hofmeyr ◽  
...  

AbstractAt-sea behaviour of central-place foraging fur seals and penguins in the Southern Ocean is understudied during the latter stages of parental care and the subsequent pre-moulting period. This biologically important period is costly to investigate due to the risk (or certainty) of losing tracking instruments when the animals moult. Early in this period, parents must meet the increasing demands of larger, more mobile offspring that are still nutritionally dependent and then the parents must recover lost body condition prior to the onset of their annual moult. This study reports late-season, at-sea movement patterns of macaroni penguins, chinstrap penguins and adult female Antarctic fur seals from the subantarctic island Bouvetøya, in relation to remotely-sensed oceanographic features. Foraging trips differing significantly in direction and distance travelled compared to those performed earlier in the breeding season, coincide with the time when offspring would be expected to become independent. On these trips, macaroni penguins moved towards the Polar Front while chinstrap penguins and Antarctic fur seals moved southward. Individuals from all three species appeared to target submesoscale ocean features once they were presumed to have been released from the constraints of feeding their young and were able to travel greater distances from the colony.


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