Age at Sexual Maturity and Pregnancy Rates of Harbour Porpoises Phocoena phocoena from the Bay of Fundy

1990 ◽  
Vol 47 (3) ◽  
pp. 561-565 ◽  
Author(s):  
Andrew J. Read
Keyword(s):  
Pregnancy Rate ◽  
Sexual Maturity ◽  
Pregnancy Rates ◽  
First Year ◽  
Bay Of Fundy ◽  
Phocoena Phocoena ◽  
Entire Sample ◽  
Young Females ◽  
Gill Net ◽  
The Mean

Age at sexual maturity and pregnancy rate were estimated from a sample of 108 female harbour porpoises Phocoena phocoena killed incidentally in a commercial gill net fishery in the Bay of Fundy during July–September, 1985–88. Estimates of sexual maturity ranged from 3.15 to 3.44 yr, depending on the method used; few individuals older than 7 yr of age were present in the sample. The mean age at first pregnancy was 3.76 yr. Pregnancy rate was estimated using two methods: (1) considering the entire sample and using the presence of a corpus luteum as indicative of pregnancy, and (2) by considering the sample collected after implantation and using the presence of a foetus as the criterion of pregnancy. Estimated pregnancy rates using these two methods were 0.86 and 0.74, respectively. Many young females failed to conceive in their first year or two of sexual maturity, but most older females in the sample were pregnant. These high pregnancy rates are indicative of annual reproduction in this population.

Changes in Growth and Reproduction of Harbour Porpoises, Phocoena phocoena, from the Bay of Fundy

1990 ◽  
Vol 47 (11) ◽  
pp. 2158-2163 ◽  
Author(s):  
Andrew j. Read ◽  
David E. Gaskin
Keyword(s):  
Sexual Maturity ◽  
Prey Availability ◽  
Simultaneous Increase ◽  
Bay Of Fundy ◽  
Commercial Fisheries ◽  
Phocoena Phocoena ◽  
Pronounced Change ◽  
Younger Age ◽  
Incidental Mortality ◽  
Growth And Reproduction

Changes in the growth and reproduction of harbour porpoises from the Bay of Fundy are described by comparing samples collected in 1969–73 and 1985–88. The most pronounced change was an increase in the length of calves, from 92.1 cm (SE 1.6) in 1969–73 to 108 cm (SE 1.3) in 1985–88. Females in 1985–88 attained sexual maturity at a significantly younger age (3.44 yr) and shorter length (143 cm) than females from the older sample (3.97 yr and 147 cm). These changes may be attributable to an increase in prey availability to individual porpoises. This presumed increase in prey availability may have resulted from a decrease in porpoise density caused by incidental mortality in commercial fisheries, a simultaneous increase in prey abundance, or a combination of these factors.

109 RELATIONSHIP BETWEEN ULTRASONIC MORPHOLOGY OF CORPUS LUTEUM IN HOLSTEIN HEIFERS AND PREGNANCY RATE AFTER EMBRYO TRANSFER

2012 ◽  
Vol 24 (1) ◽  
pp. 167
Author(s):  
A. Shirasawa ◽  
Y. Nakamura ◽  
A. Ideta ◽  
Y. Oono ◽  
M. Urakawa ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Blood Clot ◽  
Pregnancy Rates ◽  
Bovine Embryo ◽  
Tissue Area ◽  
The Mean ◽  
Rectal Palpation ◽  
Experimental Group

Recipient animals for bovine embryo transfer (ET) are routinely selected according to the morphology of the corpus luteum (CL) estimated by rectal palpation. However, rectal palpation is not a precise method of diagnosing the functional status of a CL. Ovarian ultrasonography (US) may be used to improve such diagnoses. The aim of this study was to evaluate the relationship between ultrasonographic images of CL and pregnancy rates after ET in Holstein heifers to determine whether US can be used to select recipients for ET. Recipient heifers (n = 285) were selected by detection of natural oestrus or following oestrus synchronization using a progesterone-releasing intravaginal device (PRID; ASKA Pharmaceutical, Tokyo, Japan). Transrectal US was performed immediately before ET, on Days 6 to 8 of the oestrous cycle (oestrus = Day 0), using a B-mode scanner (HS1500V; Honda Electronics Co. LTD, Aichi, Japan) equipped with a 7.5-MHz linear-array transducer designed for intrarectal placement. A cross-sectional image of the maximal area of the CL and luteal cavity was obtained. The areas of the CL and luteal cavity were each calculated using the formula for the area of an ellipse (height/2 × width/2 × π). (1) Ultrasonic morphology of CL was classified into 3 types: without cavity (n = 128), with cavity (n = 145) and with blood clot (n = 12). (2) The luteal cavity was categorized into 3 groups: small (<100 mm2, n = 93), medium (100 ≤ x < 200 mm2, n = 32) and large (≥200 mm2, n = 20). (3) Luteinized tissue area (total area of CL minus the area of the luteal cavity) was categorized into 3 groups: small (<250 mm2, n = 61), medium (250 ≤ x < 350 mm2, n = 128) and large (≥350 mm2, n = 84). In vivo–produced embryos were transferred nonsurgically into the uterine horn ipsilateral to the CL. Pregnancy was determined by transrectal US on Days 30 to 40 of gestation. The pregnancy rates of each experimental group were analysed by logistic regression. In this study, the pregnancy rate did not differ significantly in each experimental group: (1) without cavity: 77.3% (99/128), with cavity: 75.2% (109/145) and blood clot: 75.0% (9/12); (2) small cavity: 73.1% (68/93), medium: 75.0% (24/32) and large: 85.0% (17/20). The mean area of the cavity was 100.8 ± 110.3 mm2 (mean ± standard deviation) and recipients with 0 to 539.7 mm2 sized cavities had successful pregnancies (observational range was 0 to 539.7 mm2). (3) The pregnancy rates of recipients that had small, medium and large luteinized tissue were 77.0% (47/61), 75.0% (96/128) and 77.4% (65/84), respectively. The mean area of luteinized tissue was 318.9 ± 90.3 mm2 and 155.0 to 620.0 mm2 sized luteinized tissue had pregnancy success (observational range was 132.8 to 620.0 mm2). In conclusion, the results from this study indicate that the presence of a luteal cavity or blood clot has no detrimental effect on pregnancy success after ET in Holstein heifers. Furthermore, no relationship was found between luteinized tissue area at the time of ET and pregnancy rate.

Reproductive Rates of Harp Seals, Pagophilus groenlandicus (Erxleben)

1966 ◽  
Vol 23 (5) ◽  
pp. 757-766 ◽  
Author(s):  
D. E. Sergeant
Keyword(s):  
Sexual Maturity ◽  
Reproductive Rate ◽  
First Year ◽  
Published Data ◽  
Age Class ◽  
Adult Females ◽  
Pagophilus Groenlandicus ◽  
The Mean ◽  
Reproductive Rates ◽  
Lower Population

In less than a decade the mean age at sexual maturity of female harp seals of the Front, or northeastern Newfoundland population, decreased to 4 from [Formula: see text] years. Exploitation was heavy during this period and included a high proportion of seals older than 1 year. Females of the Gulf of St. Lawrence herd declined in mean age at sexual maturity over the same decade to 5 from nearly 6 years. Exploitation of this herd was lower, especially for animals older than their first year. Fertility of the adult females was likely higher in the more heavily exploited population. Published data on the White Sea population, which was reduced to low numbers, show reproduction at a lower mean age than for the present Front herd; for the Jan Mayen herd, of uncertain population status, about the same reproductive rate as the present Gulf herd. In most of the populations, samples of adult, whelped females showed the greatest number in the age-class about 1 year older than that first showing 100% of the females mature, as would be expected; however, samples from the Front herd showed dominance of an older age-class, suggesting that young adult females may to some extent segregate into separate groups. The immediate factors leading to increased reproductive rates at lower population densities were not elucidated.

Effect of cattle tick (Boophilus microplus) infestation on performance of Bos indicus cross cows and their progeny

1988 ◽  
Vol 28 (1) ◽  
pp. 1 ◽  
Author(s):  
RG Holroyd ◽  
PJ Dunster ◽  
PK O'Rourke
Keyword(s):  
Pregnancy Rate ◽  
Bos Indicus ◽  
Treated Group ◽  
Pregnancy Rates ◽  
Boophilus Microplus ◽  
Cattle Tick ◽  
First Year ◽  
The Third ◽  
Lactating Cows ◽  
Tick Counts

The effects of cattle tick infestations on liveweight and fertility of Droughtmaster (1/2 Bos indicus) cows and on calf weaning weights were determined over 3 years. Tick populations on the control (non-dipped) group of cattle fluctuated, with mean annual tick counts/side being 9.5, 8.9 and 13.6 for years 1, 2 and 3 respectively, while the treated group of cattle, which were dipped every 21 days, were free of ticks. Tick counts were not related to fertility or liveweight change in pregnant-lactating cows or to calf growtb or weaning weights. Treatment for ticks significantly (P<0.05) affected liveweight change in pregnant-lactating cows on only a few occasions, and annual liveweight changes were not significantly influenced by treatment. When lactating cow pregnancy rates were low (< 30% for control cows), treatment for ticks increased the pregnancy rate by about 100% in 2 of the 3 years, these differences being significant only in the last year. Calves in the treated group were born significantly earlier in the first year and had significantly lighter birth weights in the third year. Treated calves grew faster to weaning and had higher weaning weights (mean difference 17.9 kg) than control calves but differences were significant in the first and third years only.

Incidental mortality of harbour porpoise (Phocoena phocoena) by the gill-net fishery in the lower Bay of Fundy

1996 ◽  
Vol 53 (6) ◽  
pp. 1294-1300 ◽  
Author(s):  
E A Trippel ◽  
J Y Wang ◽  
M B Strong ◽  
L S Carter ◽  
J D Conway
Keyword(s):  
Harbour Porpoise ◽  
Bay Of Fundy ◽  
Phocoena Phocoena ◽  
Gill Net ◽  
Incidental Mortality

scholarly journals Reproductive Potential of Stone Moroko (Pseudorasbora parva, Temminck et Schlegel, 1846) (Teleostei: Cypriniformes: Gobionidae) Inhabiting Central Europe

Animals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2627
Author(s):  
Lucyna Kirczuk ◽  
Katarzyna Dziewulska ◽  
Przemysław Czerniejewski ◽  
Adam Brysiewicz ◽  
Izabella Rząd
Keyword(s):  
Central Europe ◽  
Sexual Maturity ◽  
Reproductive Potential ◽  
The Body ◽  
Sexual Cycle ◽  
First Year ◽  
Pseudorasbora Parva ◽  
Native Population ◽  
Time Period ◽  
The Mean

Similar to other invasive species, stone moroko is extending its global distribution. The present study aimed to assess the reproductive potential of stone moroko fish in a new habitat in Poland based on analysing the sexual cycle and fecundity. Fish morphometric data, age, and gonadal structures were analysed. Fish age ranged from 0+ to 5+ years. Most females and males (93% and 60%, respectively) had reached sexual maturity in the first year of their life, with the smallest length of 25 mm and 28 mm, respectively. The mean, standard length of the body was 50 mm. The spawning season was spread over four months from late-April to mid-August. Females laid eggs in portions, and the absolute and relative fecundity was 1372 and 1691, respectively. Stone moroko males were ready to spawn for a longer time period than females. The present study shows greater reproductive potential of stone moroko population in the central Europe than the native population, suggesting its successful colonisation in the new habitat.

Age, growth and condition of the Perth herring, Nematolosa vlaminghi (Munro) (Dorosomatinae), in the Swan Estuary, south-western Australia

1986 ◽  
Vol 37 (1) ◽  
pp. 105 ◽  
Author(s):  
CF Chubb ◽  
IC Potter
Keyword(s):  
Western Australia ◽  
Condition Factor ◽  
First Year ◽  
Growth Equation ◽  
Age Classes ◽  
Beach Seine ◽  
Gill Net ◽  
The Mean ◽  
Von Bertalanffy Growth Equation ◽  
First Year Of Life

The size, age and condition of Perth herring, N. vlaminghi, in the Swan Estuary in south-western Australia, were investigated between February 1977 and January 1980 using samples collected by beach seine and gill net. An examination of scale annuli showed that the population consisted predominantly of age classes 0+ to 4 +. By the end of their first year of life, Perth herring had reached mean lengths of 105 mm (= 9.8 g) in 1977, 105 mm (= 10.0 g) in 1978, and 95 mm (= 7.9 g) in 1979. The von Bertalanffy growth equation was calculated to be Lt = 381{1 -exp[- O.17(t + 0.6S)]}. During winter, the growth rate declined markedly and the mean condition factor fell to its lowest level. Perth herring started to make a major contribution to the important commercial fishery for this species during their third year of life.

Selection for fertility traits in Brahmans increases heifer pregnancy rates from yearling mating

2010 ◽  
Vol 50 (6) ◽  
pp. 345 ◽  
Author(s):  
T. J. Schatz ◽  
G. A. Jayawardhana ◽  
R. Golding ◽  
M. N. Hearnden
Keyword(s):  
Pregnancy Rate ◽  
Pregnancy Rates ◽  
Conception Rate ◽  
First Year ◽  
Weight Range ◽  
The Third ◽  
Conception Rates ◽  
Second Year ◽  
Selection For ◽  
Fertility Traits

The performance of heifers from a Brahman herd that was selected for fertility was compared with Brahman heifers sourced from commercial properties using three year-groups of heifers. Each year, conception rates from yearling mating were significantly higher in heifers from the selected herd (SEL) than in heifers sourced from commercial properties (COM), despite the average joining weight of the SEL heifers being lower each year. The pregnancy rate in SEL heifers was 24% higher (P = 0.008) in the first year, 36% higher (P = 0.005) in the second year and 45% higher (P < 0.001) in the third year. Over the 3 years of the study, the conception rate was 35% higher (P = 0.009) in SEL heifers than in COM heifers. Joining weight also affected pregnancy rates. When heifers were split into weight ranges according to their pre-joining weight, pregnancy rates were significantly higher (P = 0.018) in the heavier weight range than the lighter one. The results indicate that selection for fertility has been successful in improving conception rates from yearling mating in SEL heifers.

Decline in doe fawn fertility in southern Michigan deer

1991 ◽  
Vol 69 (1) ◽  
pp. 25-28 ◽  
Author(s):  
Louis J. Verme
Keyword(s):  
Pregnancy Rate ◽  
Odocoileus Virginianus ◽  
Sexual Maturity ◽  
Agricultural Land ◽  
Pregnancy Rates ◽  
High Fecundity

Odocoileus virginianus declined from a 60% pregnancy rate to <47% between 1952 and 1982. This change was inversely correlated (P = 0.010) with annual deer kill, which increased more than 18-fold over that period owing to herd eruption. Sustained high fecundity among doe fawns that bred suggests that nutritional resources on this prime agricultural land had not diminished during the interim. I hypothesize that the declining pregnancy rates were related to biosocial factors, namely the effect of orphaning in accelerating doe fawn sexual maturity (due to lack of maternal domination), associated with a reduction in the proportion of antlerless deer harvested as the population continued to rise over the three decades studied.

CLINICAL ANALYSIS OF CLOMIPHENE CITRATE INDUCED OVULATION IN INFERTILITY PATIENTS WITH POLYCYSTIC OVARIAN DISEASE

2021 ◽  
Vol 4 (5) ◽  
Author(s):  
Preeti Suhas Deshpande
Keyword(s):  
Pregnancy Rate ◽  
Ovulation Induction ◽  
Polycystic Ovary ◽  
Clomiphene Citrate ◽  
Multiple Pregnancy ◽  
Follicular Development ◽  
Pregnancy Rates ◽  
Initial Assessment ◽  
Infertile Women ◽  
The Mean

Background: Normo-gonadotrophic anovulation is the most prevalent anovulatory infertility type. Polycystic ovary disease (PCOS) is by far the most common cause in this category, accounting for 85 % of females who are anovulatory. Its prevalence is growing increasingly with increasing modernisation. Ovulation induction in PCOS females is a problem and the best drug for ovulation induction is still debatable. Aims & objectives: In the current research, we evaluated the efficacy of clomiphene citrate in infertile women with polycystic ovary disease for ovulation induction and pregnancy rates. Material and Methods: The present research was a prospective study conducted with PCOS, willing to participate and follow up in women with primary/secondary infertility. Rotterdam criteria were used to diagnose PCOS. Using descriptive statistics, statistical analysis was performed. Results: Initially, 140 patients in the current study were recruited. For the current research, 128 patients either born or cared for a full 6 months were considered. 21-25 years of age was the most common age group. The mean age of the patients examined was 26.34 ± 3.6 years. 55 % were having average BMI patients, while 34% were overweight. Primary infertility was present in 77 percent of patients. 73 per cent of patients had infertility duration of 1-5 years. 30 percent have a history of laparoscopic ovarian drilling in patients. In 58 percent, hirsutism was noted. Following serial USG monitoring, mono-follicular development (55 %) was more prevalent than multi-follicular development at the end of the study (45 percent). The mean thickness of the endometrium was 7.78 ± 2.58 mm. The mean days for clomiphene citrate ovulation are 14.84 ± 3.46. Average P4 values on day 21 were 11.48 ± 6.44 ng/ml. At the end of the study, 66 % ovulation rate, 28 % pregnancy rate, and 2 % multiple pregnancy incidence were noted. Conclusion: Ovulation induction with clomiphene citrate should be considered as the first line of treatment for infertile women with PCOS. Initial assessment and careful selection of patients increases pregnancy rates. Keywords: ovulation induction, polycystic ovary disease, clomiphene citrate, pregnancy rate.

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