SEARCH · PubMed Health

Results for “Reproductive performance”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 973 records · Page 54Linked to original sources

PubMed1978

Reproductive performance of ewes mated to rams heterozygous for the Massey I (t1) centric fusion (Robertsonian) translocation.

One hundred Scottish Blackface ewes were mated to New Zealand Romney rams heterozygous for the Massey I (t1) centric fusion (Robertsonian) translocation. The lambing percentage of ewes lambed was 131 and the segregation of normal to balanced heterozygous lambs was 1:1. No chromosomally unbalanced lambs were born. Nine heterozygous females were mated to a heterozygous male and produced two homozygous, three heterozygous and seven normal lambs. The homozygous male had hypoplastic testes. The results indicate that there is no significant reduced fertility with 53XYt1 rams but that fertility of 52XYt1t1 rams should be further investigated.

Animals↗

PubMed1984

Reproductive performance of broiler breeders exposed to cycling high temperatures from 17 to 20 weeks of age.

Forty male and 240 female broiler breeders were placed in cages within environmental chambers (20 males or 40 females per chamber) at 14 weeks of age. Chamber temperatures were maintained at 21.3 +/- 2.5 C, and relative humidity (RH) ranged from 40 to 50%. Ventilation rate was approximately 47.2 liters/sec per chamber, and light was provided from 0600 to 1800 hr. Feed was restricted daily according to industry recommendations, and water was provided ad libitum. From 17 to 20 weeks of age, control (C) chambers were kept at constant 21.0 +/- 1.4 C with 45 +/- 5% RH, and heat-treated (HT) chambers were cycled from 24.4 +/- 5.5 C (45 +/- 5% RH) during 1800 to 0800 hr to 36.0 +/- 2.8 C (15 +/- 5% RH) during 0800 to 1800 hr. Body weights were recorded at biweekly intervals. At 18 and 20 weeks of age, blood samples and rectal body temperatures were obtained randomly from five fasted birds per chamber at 0800 and 1400 hr. From 20 to 60 weeks of age, all birds were kept in individual cages in a conventional fan-ventilated house. Maximum temperature never exceeded 30 C, and average RH was 65.0%. Reproductive parameters were monitored and body weights were obtained at 4-week intervals. There were no significant treatment effects for body weight, body temperature, or differential leukocyte counts. Hematocrits were significantly lower for HT females than controls, and heat treatment did not result in consistent changes in plasma glucose or total proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

PubMed1991

Relationships among milk yield, metabolism, and reproductive performance of primiparous Holstein cows treated with somatotropin.

Thirty-two primiparous Holsteins were assigned to receive 0, 5.15, 10.3, or 16.5 mg/d recombinant bST. Treatment began between 28 and 35 d postpartum and continued until 60 d prior to next expected calving or 400 d postpartum. Metabolic hormones and metabolites were measured in blood weekly during the first 10 wk of treatment, and progesterone was measured in milk twice weekly to assess ovarian activity until conception. Milk production (305 d, actual) was 8350 +/- 562, 8348 +/- 515, 9571 +/- 515, and 9070 +/- 515 for cows given 0, 5.15, 10.3, or 16.5 mg/d and did not differ statistically. Insulin, glucose, NEFA and blood urea nitrogen were not influenced by dose of bST. However, insulin-like growth factor-I increased linearly with dose of bST. Days from parturition to first detected estrus, days open, and services per conception did not differ among groups; however, days from parturition to first service increased with dose of bST. Rate of detection of estrus decreased with dose of bST, resulting in a longer interval to first insemination. The lower rate of detection of estrus in bST-treated cows may have been associated with reduced expression of estrus. Additional statistical analyses were conducted to determine the relationship between metabolism, milk production, and reproduction over all doses of bST. There was a negative correlation between 305-d milk yield and glucose (r = -.44) and insulin (r = -.46) concentrations during 30 to 100 d postpartum. In stepwise regression analyses, insulin accounted for 21% of the variance in 305-d milk yield. Glucose and NEFA accounted for 18% of the variance in days open, and there was a negative correlation (r = -.32) between glucose and days open. Days open and milk production were not correlated.

Animals↗

PubMed1993

Diallel cross of three Moroccan breeds of sheep: II. Reproductive performance and productivity of purebred ewes.

A diallel cross involving three Moroccan breeds of sheep (Sardi, Beni Guil, and D'man) was analyzed by least squares procedures. A total of 456 ewes were mated to 22 rams and this resulted in 528 lambs born from 412 ewes. D'man ewes had by far the highest general performance as measured by total weight of lamb weaned, even though the average live weight per lamb was the lowest for the three breeds; this resulted from the higher number of lambs weaned per ewe for the D'man. The least squares means for litter size at birth per ewe lambing were 2.04, 1.01, and 1.11 for D'man, Beni Guil, and Sardi ewes, respectively. The comparable figures for litter size at weaning were 1.55, .90, and .99, respectively, and the least squares means for total weight of lamb weaned were 20.7, 16.9, and 18.2 kg for D'man, Beni Guil, and Sardi ewes, respectively. The comparable figures for total weight of lamb weaned per 100 kg of ewe weight were 71.1, 44.3, and 41.1 kg/100 kg for D'man, Beni Guil, and Sardi ewes. Conversely, D'man rams had the poorest breeding performances of the rams of the three breeds, and Beni Guil rams had the lowest litter mortality. The breed of ram had only small and nonsignificant effects on all measures of fertility and ewe productivity. The least squares means for number born/ewe lambing were 1.36, 1.35, and 1.44, respectively, for D'man, Beni Guil, and Sardi rams; the comparable least squares means for number weaned per ewe lambing were 1.10, 1.18, and 1.16, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

PubMed1997

Aflatoxin B1 and reproduction. I. Reproductive performance in female rats.

An experimental group of female rats was exposed to aflatoxin B1 at a dose of 7.5 mg/kg body weight daily for 14 days through oral intubation. A deleterious effect on the gonads and embryotoxicity in the experimental animals were observed. There were reductions in ovarian and uterine sizes, increases in fetal resorption, implantation loss, and intra-uterine death. The data showed significant disturbances in oestrus cycle, inhibition of lordosis, and reductions in the conception rates and litter sizes, suggesting severe impairment of fertility in the aflatoxin exposed rats. An aflatoxin blood level of 86.2 +/- 1.3 ppb was recovered in the experimental animals.

Aflatoxin B1↗

PubMed1993

Enhancement of sow reproductive performance by beta-carotene or vitamin A.

Two experiments were conducted at separate commercial farms. In Exp. 1, all primiparous sows and an equal number of multiparous sows weaned each week were randomly assigned to one of four treatment groups. Treatments consisted of one i.m. injection on the day of weaning of 0, 50, 100, or 200 mg of beta-carotene. Sows were checked for estrus with boars once daily and mated at first estrus after weaning. A sample of sows (n = 100) was selected for determination of plasma beta-carotene and vitamin A. Blood samples were obtained from another group (n = 120) 14 d after injection to determine plasma progesterone. In Exp. 2, treatments consisted of i.m. injection of 200 mg of beta-carotene, 50,000 IU of vitamin A, or vehicle on the day of weaning, on the day of mating, and on d 7 after mating. In both experiments, the sow diet was supplemented with 11,000 IU/kg of vitamin A. In Exp. 1, there was no effect of dose of beta-carotene on the interval from weaning to estrus or on the repeat service rate. There was a dose x parity interaction on the number of pigs born dead (P < .01) and born alive (P < .10), because treatment with beta-carotene did not affect reproduction in primiparous sows, but litters subsequently farrowed by multiparous sows had more pigs born alive and fewer pigs born dead. There was a dose x day interaction (P < .05) on plasma beta-carotene; beta-carotene was elevated on d 6 and 13 after injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1983

Influence of a low plane of nutrition during sexual development on subsequent reproductive performance of small white breeder toms.

Diamond White and Wrolstad breeder toms were reared to 10 weeks of age on a common nutritional regimen. Both strains were subsequently given high and low planes of nutrition to 30 weeks. Low nutrient feeds were ca. 200 kcal of metabolizable energy (ME)/kg less than high nutrient feeds, which paralleled commercial practice. Energy-protein ratio and essential amino acid profiles between nutrient levels were similar. Both planes were phased down ca. 200 kcal ME/kg between the feeds from 10 to 14 weeks to 14 to 30 weeks. All birds subsequently received the same breeder ration. Diamond Whites were heavier than Wrolstads from 2 through 10 weeks of age. Feeding the low plane of nutrition reduced body weight of both strains at 14 weeks. Growth during the 14- to 30-week-period was such that birds given the low plane feeds recovered earlier losses, and Wrolstads became heavier than Diamond Whites. Although no differences in body weight occurred throughout the breeder period that could be attributed to earlier nutrition, the low plane feeds led to significant improvements in semen and sperm yield during the early and late stages. Wrolstads accrued more fat and benefited more from the low plane of nutrition than did Diamond Whites. Results inferred that reducing fat accretion early in sexual maturity improves subsequent reproductive capacity apart from an alteration in body weight.

Animals↗

PubMed1986

Effects of di(2-ethylhexyl) phthalate on the gonadal pathophysiology, sperm morphology, and reproductive performance of male rats.

Dietary exposure of adult male F344 rats to 0, 320, 1250, 5000, or 20,000 ppm DEHP for 60 consecutive days resulted in a dose-dependent reduction in total body, testis, epididymis, and prostate weights at 5000 and 20,000 ppm. Degenerative changes were observed in testis, along with decreased testicular zinc content, reduced epididymal sperm density and motility, and increased occurrence of abnormal sperm at 20,000 ppm. There was a trend towards reduced testosterone and increased luteinizing hormone and follicle stimulating hormone in serum at 5000 and 20,000 ppm. The mean percentage of fertile animals was unchanged and reduction in fertility parameters, although not marked in severity, were correlated with gonadal effects. Average litter size was reduced at 20,000 ppm, but initial pup weights and growth were unaffected. There were no grossly observed abnormalities in the offspring and the rate of neonatal deaths was similar in control and DEHP treated groups. Characteristic toxicity manifestations of DEHP included dose-dependent enlargement of liver and reduced sperm triglycerides and cholesterol. Additionally, serum albumin and total proteins were dose dependently increased upon treatment with DEHP. Cessation of exposure to DEHP initiated partial to complete recovery from toxicity in most cases. The magnitude of recovery were variable with that of the gonads being slower than other systems. These data suggest a lack of reproductive dysfunction in F344 male rats at DEHP doses below 20,000 ppm which produced measurable testicular degeneration and afflicted epididymal sperm morphology under the present experimental conditions.

Animals↗

PubMed2006

Effects of El Niño on distribution and reproductive performance of Black Brant.

Climate in low-latitude wintering areas may influence temperate and high-latitude breeding populations of birds, but demonstrations of such relationships have been rare because of difficulties in linking wintering with breeding populations. We used long-term aerial surveys in Mexican wintering areas and breeding areas in Alaska, USA, to assess numbers of Black Brant (Branta bernicla nigricans; hereafter brant) on their principal wintering and breeding area in El Niño and non-El Niño years. We used Pollock's robust design to directly estimate probability of breeding and apparent annual survival of individually marked brant at the Tutakoke River (TR) colony, Alaska, in each year between 1988 and 2001. Fewer brant wintered in Mexico during every El Niño event since 1965. Fewer brant were observed on the principal breeding area following each El Niño since surveys began in 1985. Probability of breeding was negatively related to January sea surface temperature along the subtropical coast of North America during the preceding winter. Between 23% (five-year-olds or older) and 30% (three-year-olds) fewer brant nested in 1998 following the strong El Niño event in the winter of 1997-1998 than in non-El Niño years. This finding is consistent with life history theory, which predicts that longer-lived species preserve adult survival at the expense of reproduction. Oceanographic conditions off Baja California, apparently by their effect on Zostera marina (eelgrass), strongly influence winter distribution of brant geese and their reproduction (but not survival), which in turn affects ecosystem dynamics in Alaska.

Age Factors↗

PubMed1993

Reproductive performance of women with uterine malformations.

The fertility problems of 176 patients with uterine malformations [arcuate (n = 40), bicornuate (n = 49), bicornis-bicollis (n = 17), didelphys (n = 15), unicornuate (n = 24), subseptus (n = 14) and septate uterus (n = 17)] and of 28 women with other genital and/or urinary anomalies but with a normal uterus were studied. Ten patients with a uterine anomaly experienced infertility without other causes (6%). 142 women with uterine malformations and 26 with a normal uterus achieved pregnancy, the total number of pregnancies to date being 383 and 47 in these groups respectively. The outcome of the first pregnancy from women with uterine malformations was similar to that of all pregnancies though less significant. Only 53% of pregnancies in women with uterine malformations ended with a child surviving > 7 days, compared to 89% in women with a normal uterus. The poorest viability results were found in the bicornuate (40%) (47% of pregnancies in this group ended in early abortions), arcuate (45%) and septate uterus groups (59%). The rates of children surviving > 7 days were around 70% in the bicornis-bicollis, didelphys, unicornuate and subseptus uterus groups. Metroplasty in four cases corrected the infertility or repeated abortions in three patients. Cerclages (21) in 14 women increased the live birth rate from 21 to 62%. These results confirm earlier reports that patients with uterine malformations have higher rates of reproductive loss, pre-term delivery, breech presentation and complications that increase obstetric intervention and perinatal mortality. Moreover in our study, pregnancy outcome was poorer in the bicornuate and arcuate uterus groups than in the septate group.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

PubMed1986

Some epidemiological features and effects on reproductive performance of endemic porcine parvovirus infection.

The time of development of demonstrable antibody to porcine parvovirus (PPV) was determined for 661 gilts entering the breeding herd in a 2800 sow intensive piggery; 13.2% of these gilts did not have detectable antibody to PPV when first introduced into the breeding herd at 25 to 26 weeks of age. Exposure to PPV was found to vary in different sheds and even in different areas within a shed. Gilts that developed antibody to PPV during the first third of pregnancy were not adversely affected. Those that developed antibody during the middle third of pregnancy had fewer piglets born alive, more stillborn piglets and more mummified foetuses.

Animals↗

PubMed1980

Akodon molinae (Rodentia Cricetidae), a new laboratory animal: breeding, management and reproductive performance.

Akodon molinae, a vole mouse widely distributed in central Argentina, shows remarkable chromosome polymorphisms. It is one of the natural reservoirs of the aetiologic agent of haemorrhagic fever, and a laboratory colony could be of great help in investigating this disease. Pregnancy lasted 23 (range 21-25) days. Litters of 4-5 young were born to monogamous breeding pairs about every 30 days, with weaning at 26 days post partum. The sex ratio at birth was 505 males to 500 females: at weaning it was 460 to 440. Sexual maturity was attained at about 16 weeks of age in males and 12-20 weeks in females. Akodon molinae is easy to handle, but fighting and killing or neglect of young are problems.

Animals↗

PubMedDate not supplied

Production and reproductive performance of hexaparental and octaparental mice.

The production of hexaparental and octaparental mice following embryo aggregation is reported. These mice were progeny-tested to determine which cell components were contributing to gamete formation. One chimera (No. 15) was shown to be producing eggs from all three cell strains--white, yellow, and black. The other chimeras tested were not forming germ cells from all of the cell strains involved. The use of these animals for obtaining a minimum estimate of the number of cells giving rise to the embryo proper is discussed. The suggestion is made that multi-embryo aggregates may actually be developmentally different from normal sized embryos and this may result in modified mechanisms of cell recruitment.

Animals↗

PubMed1992

Improvement of the reproductive performance of sows by treatment with a GnRH superactive analogue.

The effect of a Hungarian-made superactive analogue of GnRH (Ovurelin, D-Phe6-GnRH-EA, Reanal, Hungary) on the postpartal sexual function of sows was monitored. GnRH treatment was carried out on day 19 before weaning. The sows were inseminated at the first oestrus after weaning. GnRH treatment markedly increased litter size at weaning, substantially reduced (to 25 and 50%, respectively) the number of sows failing to come into oestrus after weaning, and increased the number of sows coming into oestrus within one week after weaning by 42.5% and 9%, respectively. These beneficial effects were particularly apparent on the far using closed management technology.

Animals↗

PubMed1978

Effect of cholera preventative treatments on reproductive performance of turkey hens.

Turkey hens were treated with either the Clemson University (CU) strain of P. multocida, chlortetracycline, bacterin, or no cholera preventative treatment during the growing period. This was followed by CU vaccination during the production period in all except an untreated control group and resulted in no significant differences (P less than 0.05) in egg production, egg weight, fertility, hatchability, body weight, or feed consumption. Best liveability after post-production challenge with P-1059 strain of P. multocida was 92% for those treated with CU vaccine in both the grower and production periods. Hens receiving no cholera preventative treatment had only 8% liveability. These data indicate no adverse effect from treating turkey hens with CU vaccine during the production period.

Animals↗

PubMed1993

Prevaccination bovine viral diarrhea virus titers and subsequent reproductive performance in dairy heifers.

The study was conducted to determine if there was a relationship between prevaccination bovine viral diarrhea virus (BVDV) titers in 14 month-old dairy heifers and time open during first lactation, length of the conception interval, fetal survival during the second pregnancy, and age at culling. Possible associations were analyzed using nonparametric survival methods and survival distributions were described using the product-limit (Kaplan Meier) methods. Regression analysis was used to estimate the correlation between pre- and postvaccination BVDV titers three years after vaccination. Evidence of exposure to BVDV prior to 14 months of age was demonstrated by serum-virus-neutralization titers greater than 1:4 for 97% and greater than or equal to 1:128 for 67% of the 72 heifers followed. No correlation was found for 38 pairs of prevaccination and postvaccination titers (p = 0.76). The risk of being culled was high for heifers (n = 41) with very low (1:2-1:8) or very high (> or = 1:256) titers, but low for heifers (n = 31) with moderate (1:16-1:128) prevaccination titers (p = 0.098). Risk of subsequent fetal loss was high for heifers (n = 30) with very low (1:2-1:16) or very high (> or = 1:256) prevaccination titers, compared to heifers (n = 24) with moderate (1:32-1:128) titers (p = 0.084). These findings suggest that prevaccination exposure to BVDV eliciting either a very weak or a very strong serological response may contribute to subsequent reproductive inefficiency and an increased risk of culling.

Abortion, Veterinary↗

PubMed2001

Reproductive performance links to fine-scale spatial patterns of female grey seal relatedness.

Fine-scale spatial patterns of female relatedness throughout the established grey seal breeding colony of North Rona, Scotland, were investigated by accurate mapping and spatially explicit analyses of a large sample (n = 262) of mothers using variation at nine microsatellite DNA loci. Local spatial autocorrelation analyses identified locations where seals were more highly related to the colony than average. These locations were also areas where the more successful females bred, were occupied first during each breeding season, were centrally placed locations of preferred habitat types and were likely to be the locations which were the first to be colonized historically. Mothers occupying such sites achieved higher than average pup growth rates, suggesting a founder fitness benefit.

Animals↗

PubMed1992

Reproductive performance of inbred congenic Leghorns carrying different haplotypes for the major histocompatibility complex.

Twelve congenic lines of White Leghorn chickens carrying distinct haplotypes of the MHC (B blood group) but sharing a common genetic background from a highly inbred line (UCD 003) were compared. Each of the lines had been bred back to Line UCD 003 for five generations before intercrossing its members to establish its distinct genetically homozygous MHC type. Seven generations of these congenic lines were compared between 1981 and 1987 for fertility, hatchability of fertile eggs, egg production, mortality to 40 wk of age, 40-wk egg weight, and 40-wk body weight. Statistically significant differences between MHC haplotypes were found for all traits except fertility.

Animals↗