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Influence of dietary protein during the pre-breeder period on subsequent reproductive performance of large white turkeys. 1. Growth, feed consumption, and female-sex-limited reproductive traits.

Large White female turkeys of a commercial variety were used to determine the effects of low dietary protein during the pre-breeder period (12 to 32 weeks of age) on subsequent reproductive performance. Diets containing 10, 12, 14, and 17% protein were fed from 12 weeks or 20 weeks to 32 weeks of age. At 32 weeks of age, all females were fed a 17% protein breeder diet. Reproductive performance was measured for a 24-week production period. Pre-breeder feed consumption and body weight gain from 12 to 32 weeks of age increased with increased dietary protein until diets contained 14% protein. Similar results were obtained when females were fed varying protein levels from 20 to 32 weeks of age. Egg production also showed an increase with increased pre-breeder dietary protein level until diets contained 14% protein. Ten fewer eggs per hen were obtained from females previously fed the 10% protein diet than those fed the 14% (20 to 32 weeks) and 17% protein diets. Pre-breeder dietary protein level did not affect age at sexual maturity, egg weight, specific gravity or shell thickness of eggs, mortality or growth, and feed consumption of progeny. Based upon the results of this study, female breeder turkeys require at least 14% protein to 20 weeks of age and 14% from 20 to 32 weeks of age for optimum egg production.

Animals↗

An epidemiological survey demonstrating decline in reproductive efficiency with age and non-seasonality of reproductive parameters in German shepherd bitches in Kenya.

An epidemiological survey undertaken in Kenya indicated that 2 previously well-established factors, namely decline in reproductive efficiency with age, and non-seasonality of canine reproductive parameters, hold true for German shepherd (GSD) bitches in Kenya. Data collection forms were distributed to randomly selected GSD breeders and information so obtained was verified using East African Kennel Club records. Whelping was recorded throughout the year. The litter size varied from 1 to 14 pups per litter with a mean of 6.3 +/- 0.4 SD puppies. Records of 567 whelpings and 3592 puppies were studied. The mean monthly whelping rate was 47.3 +/- 7.2. There was no significant difference in the mean litter size by month (P < 0.05).

Age Factors↗

[Floral biology, reproductive system and reproductive success of Macroptilium fraternum (Fabaceae)].

Observations about the floral biology and the reproductive system of Macroptilium fraternum were made in two populations in Argentina, with different edaphic conditions, situated at the southern area of distribution of the species. The coexistence of two kind of flowers in the same plant was detected in both populations and in herbarium material from other localities: a) cleistogamous preanthesis flowers and b) pseudocleistogamous flowers. The cleistogamous preanthesis flowers possessed wings longer than 5 mm and were disposed in pubescent, erect, racemes exposed above the level of the foliage. The anthesis lasted approximately 5 hours on sunny days or 9 hours on rainy days, the right wing covered the left wing, the corolla acquired a bilabiate aspect, offering the left wing as landing platform; they produced a low quantity of nectar (0.18 +/- 0.13 microliter); they did not receive pollinator visits; approximately four hours after the beginning of the anthesis on sunny days the ovary started to grow; in the bud, the receptive stigma was covered with germinating pollen grains from the same floral unit. The pseudocleistogamous flowers possessed wings shorter than 5 mm that were disposed in brief, hirsute and prostrate racemes, non subterranean as in other Macroptilium species; the banner started to spread exposing partially the wings, the left wing limb surrounded the keel and never spread; the right wing started to spread and after 2 seconds refolded and began to wither, the ovary began to grow immediately; the flower did not offer a surface to allow visitors to settle; in the buds the stigma was receptive and found with pollen grains from the same floral unit emitting their tubes. The relative reproductive success was low (natural pollination = 8%; spontaneous self-pollination = 3%), probably due to the low pollen viability, the high percentage of seed abortion and the lack of pollinator's visits. The production of both flower types is not conditioned by edaphic factors, as they were found in plants belonging to different environments. Study of the progeny of both floral types in both populations has demonstrated that each one produces a similar amount of seeds contributing to the next generation with plants of similar characteristics (slow development, low resistance to infections and high mortality). The absence of pollinators in these flowers (in part because they preferred to visit flowers of other species with more reward and in part because of the fragmentation of the habitats), would be producing inbreeding depression in the studied populations; if the germplasm variability is not preserved, these populations situated at the Southern end of the distribution range of the species could become extinguished.

Fabaceae↗

Interrelationships between postpartum events, hormonal therapy, reproductive abnormalities and reproductive performance in dairy cows: a path analysis.

Path analysis was used to determine the interrelationships between postpartum administration of gonadotrophin releasing hormone and cloprostenol and the occurrence of reproductive disease and reproductive performance in dairy cows. The data analysed were those collected on 226 Holstein-Friesian cows calving in a commercial dairy herd during a 17 month period (May 1, 1981 to October 1, 1982). Cows administered gonadotrophin releasing hormone at day 15 postpartum experienced an improved rate of uterine involution as determined by rectal palpation nine days later. Although this improved rate of uterine involution reduced the risk of pyometritis, it actually directly delayed conception. Also, gonadotrophin releasing hormone therapy directly resulted in an increased incidence of pyometritis which in turn resulted in an increase incidence of cystic ovarian disease and anestrus. The occurrence of these abnormalities resulted in increased intervals from calving to first observed estrus, first service and conception. In addition to this effect, the administration of gonadotrophin releasing hormone was also associated with increased plasma progesterone concentrations at days 24 and 28 postpartum which delayed conception. Cloprostenol therapy at day 24 postpartum resulted in a decreased plasma progesterone concentration at day 28 postpartum which was directly and indirectly associated with a decrease in the calving to conception interval. The indirect effects were mediated by a reduction in days to first estrus. Cloprostenol therapy also directly resulted in a decreased calving to first observed estrus interval for reasons not attributable to the level of progesterone at day 28.

Anestrus↗

Chronic influence of pyrethroid supermethrin on some reproductive features in Japanese quail (140 days long avian reproduction test).

We observed the influence of chronic effect of pyrethroid supermethrin on some reproduction features in Japanese quails. They received 3 different doses (P1 10.7 mg.kg-1.day-1; P2 21.4 mg.kg-1.day-1 and P3 35.7 mg.kg-1.day-1) of the tested substance during 20 weeks. The total health status, reproduction of Japanese quails, the damage rate (degree) of the organs and tissues as well as the determination of residue in the eggs and muscles of the experimental birds showed that pyrethroid insecticide supermethrin can be considered a safe pesticide.

Animals↗

[Toxicology of reproduction and development. Changes in the male reproductive function caused by drugs and pollutants: potential effects on offspring].

Published clinical observations underline the difficulty of defining with epidemiological studies the effects that chemicals such as drugs, illicit substances environmental and workplace pollutants might have on the offspring through the male parent. The Authors highlight how defining this issue might help both guide preclinical research and evaluate correctly clinical observations which are often difficult to interpret based only on observations in the female parent. Clinical research already available shows that some chemicals are able to modify fertility by acting either at the neuroendocrine level or on the testis. However, it is more difficult to identify and quantify the potential damage to the offsprings during the different phases of pregnancy and postnatal life. Finally, the Authors discuss the parameters that should be considered to obtain an algorithm for evaluating the reproductive risk in males, along the lines of the risk for the embryo and fetus due to the use of drugs during pregnancy. Moreover, it is suggested that among the unwanted effects of drugs and pollutants, those related to the different components and phases of the male reproductive function be reported also in relation to the patient's age.

Environmental Pollutants↗

Toxicity of ebrotidine on reproduction. Toxicity on fertility and general reproductive performance, embryo-fetal toxicity and peri- and postnatal toxicity.

Reproduction toxicity studies of ebrotidine (N-[(E)-[[2-[[[2-[(diaminomethylene)amino]-4-thiazolyl]methyl] thio]ethyl]amino]methylene]-4-bromo-benzenesulfonamide, CAS 100981-43-9, FI-3542) are presented in this paper. Rats dosed with 50, 200 and 500 mg/kg p.o. of ebrotidine were used for the fertility and peri- and postnatal toxicity studies, and rabbits dosed with 25, 100 and 250 mg/kg and rats dosed with 50, 200 and 500 mg/kg of ebrotidine were used for the embryotoxicity study. The fertility study was designed in accordance with a 2-generation study protocol. The results showed that ebrotidine did not interfere with male and female gametogenesis, fertility, organogenesis, postnatal development and lactation in F0 or F1 animals. Only general or non-specific effects were attributed to treatment, such as a lower weight gain in parents or fetuses in rats, or a somewhat slower bone calcification in rats, which was shown to be recoverable and had no peri- or postnatal repercussions. Neither did the fertility study reveal a possible longer duration of gestation nor did the peri- and postnatal study show a lower weight of the F1 offspring. There was only an increase in rabbit embryonic mortality, probably related to some cases of abortion at the high dose. No potential antiandrogenic effect on the reproductive function has been found. Among the different doses used in both animal species, the maximum toxic effect-free dose was that of 25 mg/kg.

Abnormalities, Drug-Induced↗

New reproductive anomalies in fruitless-mutant Drosophila males: extreme lengthening of mating durations and infertility correlated with defective serotonergic innervation of reproductive organs.

Several features of male reproductive behavior are under the neural control of fruitless (fru) in Drosophila melanogaster. This gene is known to influence courtship steps prior to mating, due to the absence of attempted copulation in the behavioral repertoire of most types of fru-mutant males. However, certain combinations of fru mutations allow for fertility. By analyzing such matings and their consequences, we uncovered two striking defects: mating times up to four times the normal average duration of copulation; and frequent infertility, regardless of the time of mating by a given transheterozygous fru-mutant male. The lengthened copulation times may be connected with fru-induced defects in the formation of a male-specific abdominal muscle. Production of sperm and certain seminal fluid proteins are normal in these fru mutants. However, analysis of postmating qualities of females that copulated with transheterozygous mutants strongly implied defects in the ability of these males to transfer sperm and seminal fluids. Such abnormalities may be associated with certain serotonergic neurons in the abdominal ganglion in which production of 5HT is regulated by fru. These cells send processes to contractile muscles of the male's internal sex organs; such projection patterns are aberrant in the semifertile fru mutants. Therefore, the reproductive functions regulated by fruitless are expanded in their scope, encompassing not only the earliest stages of courtship behavior along with almost all subsequent steps in the behavioral sequence, but also more than one component of the culminating events.

Animals↗

Production, reproductive, and metabolic factors associated with chlamydial seropositivity and reproductive tract antigens in dairy herds with fertility disorders.

While chlamydial infections cause abortions in cattle, its role in other reproductive disorders is uncertain. This study identified the risk factors for chlamydial infection in herds with history of subfertility. We investigated the possible effects of coinfections, different metabolic parameters, abortion, ovarian cysts, pathological vaginal discharge, length of the open period, milk yield, housing conditions and age. In cows from 34 farms with elevated reproductive disorders, 41.5% had antibodies against chlamydia, while chlamydia antigen was detected in the vagina and uterus of 46.7%. A statistical relationship between seropositivity and antigen positivity was not found. Abortion (OR = 6.6) and loose housing (OR = 2.3) were risk factors for the presence of chlamydia antibodies. Furthermore, there were significant relationships between metabolic disorders and chlamydial infections. Increased levels of beta-hydroxybutaric acid (OR = 6.8) and hypocalcaemia (OR = 6.0) often accompanied chlamydia antigen in the vagina. Increased age (OR = 1.2) and pathological vaginal discharge (OR = 2.4) were identified as risk factors for chlamydia antigen in the vagina. The largest risk factor was for the association of ovarian cysts (OR = 21.5) with uterine antigen. In conclusion, chlamydial infection in dairy herd cows is best understood as a multifactorial disease.

3-Hydroxybutyric Acid↗

Urinary reproductive hormone level differences between African American and Caucasian women of reproductive age.

OBJECTIVE: To compare urinary levels of reproductive hormones in African American and Caucasian women. DESIGN: Cross-sectional study. SETTING: Ten United States Air Force (USAF) bases. PATIENT(S): African American (n = 33) and Caucasian (n = 65) women of reproductive age from a larger study of USAF women (n = 170). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Urinary endocrine end points: follicular luteinizing hormone (LH), preovulatory LH, level of LH surge peak, early follicular follicle stimulating hormone (FSH), follicular LH:FSH ratio, midluteal FSH, FSH rise before menses, early follicular estrone 3-glucuronide (E(1)3G), midfollicular E(1)3G, periovulatory E(1)3G peak, midluteal E(1)3G, early follicular pregnanediol 3-glucuronide (Pd3G), follicular Pd3G, rate of periovulatory Pd3G increase, E(1)3G:Pd3G on the day of luteal transition, slope of E(1)3G:Pd3G, and midluteal Pd3G. RESULT(S): Relative to Caucasians, African American women had significantly lower follicular phase LH:FSH ratios (mean +/- SD: 0.7 +/- 0.4 vs. 1.0 +/- 0.6), lower follicular phase Pd3G levels (1.0 +/- 0.5 vs. 1.2 +/- 0.8 microg/mg creatinine), and lower rates of periovulatory Pd3G increase (0.5 +/- 0.7 vs. 1.0 +/- 1.2 microg/mg creatinine). CONCLUSION(S): Findings of this analysis should be considered preliminary evidence of racial differences in hormone levels. Future studies are needed to determine whether these differences have clinical significance.

Adult↗

Movement of spermatozoa in the reproductive tract of adult male Spodoptera litura: daily rhythm of sperm descent and the effect of light regime on male reproduction.

Sperm production and movement from the fused testes into the male reproductive tract of the common cutworm Spodoptera litura were studied in insects maintained in a 12h:12h light dark (LD) regime. Two types of sperm bundles, eupyrene (nucleated) and apyrene (anucleate) were present in the adult testes. Eupyrene bundles constituted about 25% of the total. Descent of spermatozoa from the testes into the upper vas deferens (UVD) first occurred about 24-30h before adult eclosion. On entering the reproductive tract, eupyrene spermatozoa remained in bundles while apyrene bundles became dissociated before they reached the UVD. Downward movement of both eupyrene and apyrene spermatozoa within the male tract occurred in a daily rhythm. Sperm descent from the testes into the UVD occurred during the early scotophase, followed by their further descent into the seminal vesicle (SV) during the photophase. Spermatozoa remained in the SV for only a short duration, whence sperm quickly passed through the lower vas deferens into the duplex, which acted as the main sperm storage organ until mating was initiated. During mating 80% of sperm left the duplex, but mating did not influence the number of sperm bundles that subsequently descended into the duplex or the rate of their descent. There was no evidence of sperm reflux. Rearing in constant light (LL) and in constant dark (DD) reduced the number of eupyrene sperm present in the testes of adults that emerged in LL and DD compared to controls (LD), although there was no significant effect on the number of apyrene sperm in the testes. The rhythmic pattern of sperm descent was suppressed in both LL and DD regimes, and the number of sperm in the duplex was adversely affected, with a marked impact in LL reared insects. Male longevity, mating behaviour, oviposition and fertility were found to be more severely affected in LL than in DD.

Journal Article↗

Evolution of reproductive systems in filamentous ascomycetes. II. Evolution of hermaphroditism and other reproductive strategies.

The evolution of different reproductive systems in filamentous ascomycetes is studied in a population genetic model. These fungi differ essentially from higher plants and animals because mating types can exist in addition to male and female gametes, and the conidia serve as both male gametes and asexual spores; moreover, selfing is genetically equivalent to asexual reproduction in these haploid organisms. A variable fitness of ascospore production is predicted as the explanation for the evolution of two systems that abundantly exist in nature: hermaphroditism in heterothallic species and the formation of both asexual and sexual spores in homothallic species. Imperfect fungi will evolve if sexual spores do not show a remarkably higher fitness than asexual spores.

Ascomycota↗

Analysis of transcripts encoding novel members of the mammalian metalloprotease-like, disintegrin-like, cysteine-rich (MDC) protein family and their expression in reproductive and non-reproductive monkey tissues.

A number of sequence-related, cysteine-rich proteins containing metalloprotease-like and disintegrin-like domains (the MDC protein family), at least one of which has been shown to play a role in egg recognition during fertilization, are abundantly expressed in the mammalian male reproductive tract. In this paper we report the cloning and sequence analysis of three closely related isoforms of a novel member of this family which are expressed not only in the testis, but also in the liver, albeit at a lower level. Using a PCR-based approach we also demonstrate the presence of transcripts encoding additional, novel, disintegrin-containing proteins, in the liver and epididymis. We conclude that while some members of the MDC family are specific to the reproductive tract, suggesting functions peculiar to those tissues, others have a broader tissue distribution and may therefore play a more general role in integrin-mediated cell-cell recognition, adhesion or signalling.

ADAM Proteins↗

Reproductive toxicology of 1,3-diphenylguanidine: analysis of induced sperm abnormalities in mice and hamsters and reproductive consequences in mice.

The effects of 1,3-diphenylguanidine (DPG) on seminal cytology in hybrid mice and inbred Syrian golden hamsters and on testicular histology and reproductive toxicity in mice were monitored. Treatment consisted of chronic exposure of hamsters and mice to DPG in 0.025% acetic acid ad libitum. Sperm morphology and sperm count, testicular cytology and histology, and reproductive toxicity were monitored 1 wk after exposure. The results show that DPG induces (1) time- and dose-dependent morphologically anomalous sperm in mice and hamsters; (2) significant decreases in sperm count and testicular weight; (3) irregularly shaped seminiferous tubules characterized by the absence of a defined basement membrane, loss of interstitial cells, and limited number of spermatids and spermatozoa in the lumen of the tubules; and (4) reduced fertility indices, implants per pregnancy, and fetal mortality in mice. The coincidence of increased morphologically anomalous sperm and drastic reductions in fertility indices and implants per pregnancy is suggestive of developmental disturbances in the preleptotene and late-spermatogonial cells (5-7 wk after treatment).

Animals↗

Estrogenicity of the isoflavone metabolite equol on reproductive and non-reproductive organs in mice.

Equol, a metabolite of the phytoestrogen daidzein, is present at significant levels in some humans who consume soy and in rodents fed soy-based diets. Equol is estrogenic in vitro, but there have been limited studies of its activity in vivo. We evaluated equol effects on reproductive and non-reproductive endpoints in mice. Ovariectomized age-matched (30-day-old) female C57BL/6 mice were fed phytoestrogen-free diets and given a racemic mixture of equol by daily injections (0, 4, 8, 12, or 20 mg [kg body weight](-1) day(-1)) or in the diet (0, 500, or 1,000 ppm) for 12 days. Mice were killed, and serum concentrations of total and aglycone equol were measured. Total serum equol concentrations ranged from 1.4 to 7.5 microM with increasing doses of injected equol, but uterine weight increased significantly only at 12 and 20 mg (kg body weight)(-1) day(-1). Dietary equol at 500 or 1,000 ppm produced total serum equol concentrations of 5.9 and 8.1 microM, respectively, comparable with those in rodents consuming certain high-soy chows; the proportion of equol present as the free aglycone was much lower with dietary administration than injections, which may be a factor in the greater biological effects induced by injections. Dietary equol did not significantly increase uterine weight. Increasing dietary and injected equol doses caused a dose-dependent increase in vaginal epithelial thickness. Uterine epithelial proliferation was increased by equol injections at 8-20 mg (kg body weight)(-1) day(-1) and 1,000 ppm dietary equol. Neither dietary nor injected equol decreased thymic or adipose weights. In conclusion, equol is a weak estrogen with modest effects on endpoints regulated by estrogen receptor alpha when present at serum levels seen in rodents fed soy-based diets, but quantities present in humans may not be sufficient to induce estrogenic effects, although additive effects of equol with other phytoestrogens may occur.

Adipose Tissue↗