scholarly journals Preliminary results on the use of diagnostic ultrasonography as a management tool to quantify egg production potential in breeding ostrich (Struthio camelus australis) females

2002 ◽  
Vol 73 (2) ◽  
Author(s):  
H. Lambrechts ◽  
S.W.P. Cloete ◽  
D. Swart ◽  
J.P.C. Greyling
Keyword(s):  
Breeding Season ◽  
Reproductive Performance ◽  
Egg Production ◽  
Management Tool ◽  
Production Potential ◽  
Future Studies ◽  
Diagnostic Ultrasonography ◽  
The Mean ◽  
Breeding Seasons ◽  
Follicular Activity

An ostrich breeding flock, joined as individual breeding pairs (n = 136 pairs), was used to investigate the possibility of diagnostic ultrasonography as a method to predict the reproductive performance of ostrich females during a breeding season. Follicular activity was easily detected and quantified by using diagnostic ultrasonography. One to 8 follicles were recorded in 25 % of females scanned at the beginning of the 9-month breeding season. At the end of the breeding season, 1-3 follicles were observed in 28.7 % females. Females in which follicular activity was observed came into production earlier than those in which no follicles were observed, with the mean (±SE) number of days to the production of the 1st egg being 22.3 ± 12.5 and 87.4 ± 7.2 days, respectively. Females in which follicular activity was observed at the beginning of the breeding season, produced on average 181 % more eggs during the 1st month of the breeding season (P < 0.01) than females in which no follicular activity was observed (6.67 ± 0.70 vs 2.37 ± 0.41 eggs). Egg production over the first 2 months of breeding and over the entire breeding season were similarly affected (P <0.01), with the mean number of eggs produced over the first 2 months of the breeding season being 14.7 ± 1.5 for females with observed follicular activity and 7.4 ± 0.9 eggs for females with no observed follicular activity. Females in which follicular activity was observed at the end of the breeding season produced on average 108 % more eggs (P<0.01) during the last month of the breeding season than females in which no follicular activity was observed (2.77 ± 0.43 vs. 1.33 ± 0.27 eggs). There was a tendency (P = 0.06) for egg production over the last 2 months to be similarly affected (6.10 ± 0.85 vs 4.19 ± 0.54 eggs). No relationship with egg production over the entire breeding season was found for the end-of-the-breeding-season observations. Diagnostic ultrasonography can thus be used as a management tool to identify reproductively healthy ostrich females and also females with a higher egg production potential over a period of 2 months after or prior to assessment. Future studies should focus on the development of the technique to predict reproductive performance over entire breeding seasons for selection purposes.

scholarly journals Effect of exogenous progesterone treatment on ovarian steroid hormones and oxidant and antioxidant biomarkers during peak and low breeding seasons in dromedary she-camel

2019 ◽  
Vol 12 (4) ◽  
pp. 542-552
Author(s):  
Amal M. Abo El-Maaty ◽  
Ragab H. Mohamed ◽  
Heba F. Hozyen ◽  
Adel M. El-Kattan ◽  
Mona A. Mahmoud ◽  
...  
Keyword(s):  
Steroid Hormones ◽  
Breeding Season ◽  
Management Tool ◽  
Seasonal Effect ◽  
Glutathione S Transferase ◽  
Sod Activity ◽  
Blood Concentrations ◽  
Exogenous Progesterone ◽  
Antioxidant Markers ◽  
Breeding Seasons

Background: Research about the effects of progesterone (P4) and the relationship of P4 to oxidative stress has been achieved in ruminants but not enough in camels Aim: This study evaluated the effect of exogenous P4 hormone using CIDR for 7 days on blood concentrations of steroid hormones and oxidative status of dromedary she-camels during peak and low breeding seasons. Materials and Methods: The present work was conducted on ten dark dromedary she-camels which were synchronized using a controlled internal drug release (CIDR) for 7 days as a reproductive management tool during peak breeding (November-April) and low breeding season (May-October). The blood samples were collected each other day from CIDR insertion until the end of experiment 5 days after the removal of CIDR. Camels were examined for P4, estradiol (E2), and testosterone (T) as well as malondialdehyde (MDA) as indicator of lipid peroxidation and nitric oxide, superoxide dismutase (SOD), and glutathione-S-transferase as antioxidant markers. Results: Results revealed that P4 was higher during peak breeding season than low breeding season. While the levels of P4 increased during CIDR insertion and declined at CIDR removal and thereafter during breeding season, its concentrations declined after CIDR application during the non-breeding season. On the other hand, blood E2 and testosterone levels decreased after CIDR insertion in both high and low breeding seasons with higher serum E2 concentrations during the peak than the low breeding season. MDA concentrations and SOD activities were significantly (p<0.05) high on day 3 after CIDR insertion during the breeding and non-breeding seasons. During both the seasons, GSH levels decreased after CIDR removal in camels. However, MDA was lower during non-breeding season than high breeding season with no seasonal effect on SOD activity. Conclusion: Exogenous P4 treatment through CIDR in dromedary camels could be more efficient during breeding season than non-breeding season, and effects on circulating oxidant/antioxidant biomarkers and their return to normal levels might refer to the adaptation of camels to CIDR by modulating their oxidant and antioxidant levels.

519. INFLUENCE OF THE DURATION OF CIDR INSERTION ON OVARIAN RESPONSES IN AN eCG PROGRAM DURING NON-BREEDING SEASON IN EWES

2009 ◽  
Vol 21 (9) ◽  
pp. 118
Author(s):  
R. Salehi ◽  
H. Kohram
Keyword(s):  
Breeding Season ◽  
Weight Maintenance ◽  
Live Weight ◽  
Standing Position ◽  
Beneficial Effects ◽  
The Mean ◽  
Group 2 ◽  
Maintenance Ration ◽  
Group 1 ◽  
Follicular Activity

The aim of this study was to investigate the effect of 14 versus 7 days CIDR insertion before eCG treatment on superovulatory responses during non-breeding season in ewes. 10 Iranian Shall ewes, between 2 and 3 years old were kept inside during the experiment period and were fed a live weight maintenance ration. Ewes were randomly assigned to 1 of 2 groups. CIDR was inserted to the ewes of group 1 for 14 days and for 7 days to group 2. Each ewe received 1500 IU eCG on the day of CIDR removal. Ovarian follicular activity was monitored by transrectal ultrasonography on the days of eCG treatment, estrus, and 7 days after estrus to monitor the number of corpus lutium. During examination the animals were held in a standing position. Scanning of both ovaries was recorded using a MP4 player. The number of medium and large follicles (≥3 mm in diameter) were recognized, measured and mapped to their location using printed images of both ovaries. Data were analyzed using GLM procedure of the SAS. The results presented in Table 1 shows that the ovarian responses in terms of the number of ≥3 mm follicles at estrus is greater (P<0.05) in group 1 than group 2 ewes. The mean number of CL after eCG injection in group 1 and 2 were also significantly different (3.6±0.24 vs 2.4±0.51; P<0.05). The results showed that the 14 days synchronization before eCG treatment during non-breading seasons in ewes had the beneficial effects on ovarian responses.

Fitness responses to co-infestation in fleas exploiting rodent hosts

Parasitology ◽  
2015 ◽  
Vol 142 (12) ◽  
pp. 1535-1542 ◽  
Author(s):  
IRINA S. KHOKHLOVA ◽  
ELIZABETH M. DLUGOSZ ◽  
BORIS R. KRASNOV
Keyword(s):  
Reproductive Performance ◽  
Egg Production ◽  
Egg Size ◽  
Experimental Treatment ◽  
Single Species ◽  
Mixed Species ◽  
Species Groups ◽  
The Mean ◽  
Mixed Species Groups

SUMMARYTo understand mechanisms behind positive interspecific co-occurrences in flea infracommunities, we asked whether co-infestation results in an increase of flea fitness (quantity and/or quality of the offspring). We studied reproductive performance of Xenopsylla ramesis and Parapulex chephrenis when they exploited their characteristic host (Meriones crassus and Acomys cahirinus, respectively) either alone or together with another species. We used egg production, the number of new imagoes, pre-imaginal survival and egg size as fitness-related variables and predicted that fitness will be higher in fleas feeding in mixed- than in single-species groups. In both fleas, mean number of eggs produced per female flea did not depend on experimental treatment. No effect of single- vs mixed-species infestation on the mean number of new imagoes per female and the number of emerged imagoes per egg was found for X. ramesis, whereas both these numbers were higher in mixed- than in single-species groups for P. chephrenis. X. ramesis produced eggs of similar size independently of treatment, whereas eggs produced by P. chephrenis in mixed-species groups were significantly larger than eggs produced in single-species groups. We conclude that an increase in reproductive performance as a response to co-infestation may be one of the mechanisms behind aggregative structure of flea infracommunities. However, this response may vary among flea species.

Home range of stoats (Mustela erminea) in podocarp forest, south Westland, New Zealand: implications for a control strategy

2001 ◽  
Vol 28 (2) ◽  
pp. 165 ◽  
Author(s):  
Craig Miller ◽  
Mike Elliot ◽  
Nic Alterio
Keyword(s):  
New Zealand ◽  
Home Range ◽  
Breeding Season ◽  
Convex Polygon ◽  
Home Ranges ◽  
Convex Polygons ◽  
Minimum Convex Polygon ◽  
Mustela Erminea ◽  
The Mean ◽  
Breeding Seasons

The home range of stoats (Mustela erminea) was determined as part of a programme to protect Okarito brown kiwi chicks (Apteryx australis) ‘Okarito’, from predation. Twenty-seven stoats were fitted with radio-transmitters and tracked in two podocarp (Podocarpaceae) forests, in south Westland, New Zealand, from July 1997 to May 1998. Home-range area was determined for 19 animals by minimum convex polygons and restricted-edge polygons, and core areas were determined by hierarchical cluster analysis. The mean home ranges of males across all seasons calculated by minimum convex polygon (210 28 ha ( s.e.)) and restricted-edge polygon (176 29 ha) were significantly larger than those of females across all seasons (89 14 ha and 82 12 ha). The mean home range of males calculated by minimum convex polygon during the breeding season (256 38 ha) was significantly larger than the mean home range pooled across the non-breeding seasons (149 16 ha), whereas that calculated by restricted-edge polygon was not significantly different. The mean home range of females during the breeding season was not significantly different from that in the non-breeding seasons when estimated by either method. Overlap of home ranges was observed within and between sexes in all seasons, with the greatest proportion of home range overlap being male–female. The mean home range of females in spring and summer is used to guide the spacing of control stations.

scholarly journals Multiple nesting attempts and long breeding seasons of Mimus gilvus (Aves: Mimidae) in southeastern Brazil

2019 ◽  
Vol 36 ◽  
pp. 1-8 ◽  
Author(s):  
Rodrigo Morais ◽  
Luiz Carlos Araújo ◽  
Gleidson Ramos Silva ◽  
Charles Duca
Keyword(s):  
Life History ◽  
Clutch Size ◽  
Plant Species ◽  
Breeding Season ◽  
Good Choice ◽  
Southeastern Brazil ◽  
Breeding Period ◽  
Breeding Parameters ◽  
The Mean ◽  
Breeding Seasons

This study describes aspects of the life history of the Tropical MockingbirdMimusgilvus(Vieillot, 1808), including the breeding period, clutch size, nestlings and a list of plants used for nesting. Nests were monitored in an area of Restinga (sand-coastal plain) habitat in a protected area in southeastern Brazil. The data from 181 nests during five breeding seasons (2010-2014) showed that the Tropical Mockingbird has a long breeding season (26.1 ± 2.6 weeks) with up to two peaks of active nests from August to March. The breeding pairs made up to four nesting attempts in the same breeding season. The mean (± SD) clutch size was 2.4 ± 0.6 eggs (n = 169). The mean (± SD) incubation period was 14 ± 0.6 days, and the nestling remained in the nest for 14.5 ± 2.2 days. The nests were built on thirty plant species, andProtiumicicariba(DC.) Marchand. was the plant species most commonly used for nesting. The breeding parameters of the Tropical Mockingbird are similar to those of other Mimidae species. The knowledge gained from this study makes the Tropical Mockingbird a good choice for future studies, particularly for testing ecological and evolutionary hypotheses regarding life history attributes, habitat selection and parental investment.

scholarly journals Reproductive performance in a cat colony over a 10-year period

1970 ◽  
Vol 4 (1) ◽  
pp. 99-112 ◽  
Author(s):  
Roy Robinson ◽  
H. W. Cox
Keyword(s):  
Sex Ratio ◽  
Litter Size ◽  
Reproductive Performance ◽  
Late Summer ◽  
Early Spring ◽  
Inverse Relation ◽  
Future Studies ◽  
Reproductive Life ◽  
Subsequent Loss ◽  
The Mean

Various aspects of reproductive performance in a cat colony are analysed in order to provide a basis for future studies. The aspects considered are: effect of mortality on litter size at different stages, and differential effect of losses on sex ratio of kittens reared; trend in litter size for successive parities; monthly variation in frequency of litters and litter size; output of kittens per queen per year. The sex ratio for live kittens was found to be 99.3 males per 100 females. Significant lower sex ratios of 65.6 and 79.7 were found in stillborn and in kittens which died between birth and weaning respectively. The mean litter size was 4.20 born (4.07 after deducting stillbirths), 3.65 at weaning. An inverse relation was found between incidence of stillbirths and subsequent loss before weaning. The mortality rate in each case was 1.5 kittens per affected litter. The mean litter size was smaller for the first litter but then increased to a constant 'plateau' until almost the end of the queen's reproductive life. Litters were produced throughout the year, but with greater frequency in the early spring months and again in the late summer. Litter size was greater in the summer months. Kitten mortality was lower in the summer than in the winter. A mean of 10.8 kittens were born per queen per year, and the mean number weaned was 9.4, representing a survival rate of 87 per cent.

scholarly journals Observational study on the breeding performance of emus (Dromaius novaehollandiae) in Brazil

2020 ◽  
Vol 72 (6) ◽  
pp. 2157-2164
Author(s):  
J.C.P. Quintero ◽  
L.F.L. Calixto ◽  
A.J. Almeida ◽  
Y.R. Moreira ◽  
S.S. Rocha ◽  
...  
Keyword(s):  
Observational Study ◽  
Production Rate ◽  
Breeding Season ◽  
Egg Production ◽  
Total Production ◽  
Breeding Performance ◽  
Production Potential ◽  
Dromaius Novaehollandiae ◽  
Different Ages

ABSTRACT The objective of this study was to describe emus’ breeding performance in Brazil at different ages, grouped in couples or colonies. The duration of the breeding season and the production of eggs per female housed were recorded, and the productivity and breeding variables were associated with the variation of the photoperiod. The total production of the flock was 180 eggs, and the breeding season lasted 167 days (April-September), a period with an average of 11 h and 11min of daylight. The breeding season lasted 113, 133 and 82 days, the numbers of eggs produced per female were 7.29, 25.67 and 17.3, and productivity values were 31.6, 38.6, and 45.4% in the groups of birds with ages of two, four and seven years, respectively. The breeding season in 2016 occurred between April and August in Brazil. Older birds tended to start breeding later. The production rate observations indicated that earlier peak production was associated with lower egg production potential. Finally, there was a tendency for better breeding performance of birds housed in couples than in groups with more birds.

Growth, fecundity, and reproductive biology in the pedunculate cirripede Pollicipes polymerus at San Juan Island, Washington

1981 ◽  
Vol 59 (6) ◽  
pp. 893-901 ◽  
Author(s):  
Cindy Arey Lewis ◽  
Fu-Shiang Chia
Keyword(s):  
Growth Rate ◽  
Breeding Season ◽  
Egg Production ◽  
San Juan ◽  
Adult Size ◽  
Pollicipes Polymerus ◽  
Breeding Cycles ◽  
The Mean ◽  
Eagle Point ◽  
Intertidal Level

Four populations of Pollicipes polymerus were sampled monthly for 26 months at two localities and two intertidal levels at San Juan Island, Washington, to determine the breeding season near the northern limit of the distribution of the species and for the comparison of growth, breeding cycles, and fecundity between the four populations.Pollicipes polymerus may reach a rostral–carinal length of 17 mm and sexual maturity during its 1st year after settlement. Subsequently, growth rate is reduced to about 2 mm in rostral–carinal length per year. The mean adult size increases from high intertidal level, Edward's Reef to low intertidal level, Edward's Reef to high intertidal level, Eagle Point to low intertidal level, Eagle Point. Juvenile growth rates, the percentage of breeding adults in an average month, and the mean monthly egg production also followed the above trend. Pollicipes polymerus breeds from late April through early October with a peak in July. The breeding season of the population at Eagle Point is longer than that of Edward's Reef. Obvious environmental factors that may have some effects on fecundity, growth rate, and the breeding season include temperature, wave action, food supply, and salinity. Preferred conditions include heavy surf and oceanic salinity.

Notodiaptomus incompositus (Brian, 1925) (Copepoda, Calanoida) reared in the laboratory: growth experiments and reproductive aspects

Crustaceana ◽  
2017 ◽  
Vol 90 (5) ◽  
pp. 517-533
Author(s):  
D. O. Ortiz ◽  
E. Muxagata ◽  
J. G. F. Bersano
Keyword(s):  
Egg Production ◽  
Developmental Time ◽  
Zooplankton Biomass ◽  
Future Studies ◽  
Egg Incubation ◽  
Great Relevance ◽  
Biological Aspects ◽  
The Mean ◽  
Total Zooplankton Biomass ◽  
Growth Experiments

The calanoid copepodNotodiaptomus incompositus(Brian, 1925) is an important contributor in limnic environments in Southern South America, where it can attain high densities and contribute significantly to the total zooplankton biomass in water bodies in Argentina, Uruguay and Brazil. However, little is known about the reproductive biology of this species. In the present study, biological aspects like developmental time, egg production and growth rate were assessed through cultures in the laboratory where copepods were fedChlamydomonascf.pumilioniformis(Chlamydophyceae) cultured in WC medium. The average time of egg incubation was 51 h at 20°C and the mean development time from nauplii to adult was 14 days. The carbon weights ofN. incomposituseggs and females were 0.08 and 2.38 μg C, respectively. The growth rates of all copepodite stages were determined and ranged between 0.073 and 0.447 day−1. This study revealed interesting reproductive aspects of the copepodN. incompositus, generating information that will be of great relevance for future studies with this species.

Attainment of puberty and reproductive performance in Clun Forest ewe lambs

1972 ◽  
Vol 78 (1) ◽  
pp. 39-45 ◽  
Author(s):  
Ó. R. Dýrmundsson ◽  
J. L. Lees
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Breeding Season ◽  
Reproductive Performance ◽  
First Year ◽  
Cyclic Activity ◽  
Breeding Activity ◽  
Ewe Lambs ◽  
Wide Range ◽  
The Mean

SUMMARYCertain aspects of puberal development and reproductive performance in Clun Forest ewe lambs with a wide range of birth dates were investigated during the two seasons 1969–71. Of 33 ewe lambs born in the spring of 1969, 26 exhibited their first oestrus at a mean date of 8 November 1969 ± 2·5 days, the mean age being 228·3 ± 2·4 days and the mean body weight 36·3 ± 0·9 kg. The lambs which failed to breed in their first year, together with lambs born in the autumn of 1969, attained puberty during the autumn of 1970. Twenty-three ewe lambs carried foetuses to term in the spring of 1970 and had a mean lambing rate of 113·0 ± 7%. Of 84 ewe lambs born in the spring of 1970, 73 attained puberty in the first year of life at a mean date of 11 November 1970 ± 2·7 days, the mean age being 223·7 ± 3·0 days and the mean body weight 32·2 ± 0·5 kg. Cyclic activity of ewe lambs born in 1970 was recorded throughout their first breeding season. They experienced their last oestrus of the season at a mean date of 24 January 1971 ± 2·2 days, the mean age being 296·9 ±3·9 days and the mean body weight 32·4 ± 0·6 kg. The mid-breeding season was 18 December 1970, coinciding with the shortest days, and the mean number of heats exhibited throughout the season was 5·15 ± 0·24 per lamb.Marked individual variation existed in age and body weight at puberty and in breeding activity, largely due to differences in date of birth and growth rate during rearing. Ewe lambs born early tended to experience their first oestrus earlier in the season than late born lambs but they did so at a higher age and heavier body weight. Fast growth rate and earliness of puberty were associated with extended duration and enhanced regularity of cyclic activity. Time of birth was clearly of fundamental importance in relation to the onset and duration of breeding activity in the ewe lambs included in the present study.Adult rams of three breeds were found to vary consistently in the proportion of ewe lambs which they detected in oestrus, rams of the lambs' own breed being most efficient.

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