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PubMed1980

[Maturation and in vitro fertilisation of human oocytes recovered after spontaneous ovulation or after induction of ovulation by use of gonadotrophins (preliminary results) (author's transl)].

Maturation and/or in vitro fertilisation of human oocytes was carried out on 70 oocytes recovered from 56 young women who had normal periods and were having laparoscopy for tubal sterility. Five oocytes were recovered in the pre-ovulatory phase of spontaneous cycles by the use of ultrasound determination of follicular growth and the presence of an LH peak estimated from urine levels. 65 oocytes were obtained by puncture of follicules that had been stimulated using HMG/HCG 32-36 hours after HCG had been injected. 66 per cent of these eggs showed signs of degeneration before culture. The immature oocytes which were cultured for 42-46 hours at 36 degrees C with or without gonadotrophins underwent meoisis in 80 per cent of cases and 41 per cent expelled their first polar body. None of these oocytes could be fertilised in vitro, whereas 50 per cent of the oocytes that were recovered in metaphase II and fertilised in vitro had reached the stage of pronuclei 20 hours later. Ultrastructural and cytogenic studies will be carried out to ascertain the quality of these eggs before any attempt is made to reimplant.

Adult↗
PubMed2003

In vitro and in vivo comparison of egg yolk-based and soybean lecithin-based extenders for cryopreservation of bovine semen.

Semen diluents containing egg yolk as a cryoprotectant may pose hygienic risks and are difficult to standardize. Although a new generation of semen diluents free of animal ingredients is available, egg yolk-containing extenders are still widely used for cryopreserving semen. We compared the effects of using different extenders on bovine sperm function in vitro and on fertility in vivo. A soy lecithin extender (SL; AndroMed) and an egg yolk-containing (TRIS-EY) extender were tested. No differences (P>0.05) were detected between the two extenders for sperm-zona pellucida binding capacity (HZI=115+/-13). Assessment of the inducibility of the acrosome reaction with progesterone showed no differences (P>0.05) between extenders for live acrosome-reacted sperm (15+/-2.36 and 14.42+/-2.02%, respectively, for SL and TRIS-EY). However, post-thaw sperm motility was significantly lower (P<0.05) when semen was extended in the TRIS-EY diluent. Field trials revealed that nonreturn rates of SL-extended semen showed significantly higher insemination success (P<0.0001) compared with the nonreturn rates for the TRIS-EY extender (70.45 and 67.85%, respectively). We suggest that consistent with quality standards that should be required for cryoprotectant media and because of the superior quality of the egg yolk-free extender, a defined soybean lecithin-containing diluter might be the better choice as a semen extender in the future.

Acrosome↗
PubMed2005

Effect of microbial phytase on production performance of White Leghorn layers fed on a diet low in non-phytate phosphorus.

1. An experiment with 150 White Leghorn layers was conducted to examine the effect of microbial phytase supplementation of low non-phytate phosphorus (NPP) diets on egg production, eggshell quality, bone mineralisation and retention of nutrients at 32-48 weeks of age. 2. Four isonitrogenous and isocaloric diets were formulated to contain 1.2, 1.8, 2.4 and 3.0 g NPP/kg diet with the two lowest NPP (1.2 and 1.8) supplemented with microbial phytase (Biofeed Phytase, India) at 500 FTU per kg diet. Each diet was offered ad libitum to 5 replicates of 5 layers throughout the experiment. 3. Body weight gain was reduced significantly in the layers fed on the 1.2 g/kg NPP diet as compared to those given diets containing 1.8-3.0 g/kg. Addition of phytase to the 1.2 g/kg diet significantly enhanced the body weight and was comparable with those given diets containing 1.8-3.0 g/kg NPP. 4. No additional advantage resulted from enhancing the NPP levels beyond 1.8 g/kg or adding phytase to a diet containing 1.8 g/kg NPP. 5. Hen d egg production, food intake, food efficiency, shell weight, shell thickness, shell strength and tibia strength followed the same trends as above. However, adding phytase to the 1.8 g/kg NPP diet significantly enhanced tibia ash. Egg weight, specific gravity and Haugh units were influenced by neither NPP concentration nor phytase supplementation. 6. Adding phytase to the 1.2 g/kg NPP diet significantly enhanced nitrogen and phosphorus retention. 7. It was concluded that addition of 500 FTU of microbial phytase/kg diet can allow the reduction of NPP content to 1.2g/kg in the layer diet, eliminate inorganic phosphorus supplementation and results in significant reduction of nitrogen and phosphorus excretion without affecting the production performance of layers.

6-Phytase↗
PubMed2005

Sex-biased investment in yolk androgens depends on female quality and laying order in zebra finches (Taeniopygia guttata).

The Trivers-Willard hypothesis predicts sex biases in parental investment according to parental condition. In addition, parents may need to sex bias their investment if there is an asymmetry between the sexes in offspring fitness under different conditions. For studying maternal differential investment, egg resources are ideal subjects because they are self contained and allocated unequivocally by the female. Recent studies show that yolk androgens can be beneficial to offspring, so here we test for sex-biased investment with maternal investment of yolk testosterone (T) in zebra finch (Taeniopygia guttata) eggs. From the Trivers-Willard hypothesis, we predicted females to invest more in male eggs in optimum circumstances (e.g. good-condition mother, early-laid egg), and more in female eggs under suboptimal conditions (e.g. poor-condition mother, late-laid egg). This latter prediction is also because in this species there is a female nestling disadvantage in poor conditions and we expected mothers to help compensate for this in female eggs. Indeed, we found more yolk T in female than male eggs. Moreover, in accordance with our predictions, yolk T in male eggs increased with maternal quality relative to female eggs, and decreased with laying order relative to female eggs. This supports our predictions for the different needs and value of male and female offspring in zebra finches. Our results support the idea that females may use yolk androgens as a tool to adaptively manipulate the inequalities between different nestlings.

Androgens↗
PubMed1987

Comparison of several induced molting methods on subsequent performance of single comb White Leghorn hens.

Seventy-two-week-old Single Comb White Leghorn hens were induced to molt by 11 different methods 1) to determine the utility of molt-inducing procedures that employ full feeding, limited feeding, and fasting and 2) to determine the postmolt performance of hens induced to molt by fasting to varying degrees of body weight reduction (BWR) then fed postfast, prelay (PF-PL) diets varying in nutrient density. Induced molt treatments were full feeding of 10 and 15% guar meal diets to 30% BWR; limited feeding by withholding feed to 30% BWR, except for 6-hr feeding periods on every 3rd, 4th, and 5th recurring day; fasting to 25, 30, or 35% BWR then feeding either a pullet developer ration or a fortified molt ration (FR) for 21 days. Egg production, egg weight, shell quality, Haugh unit, feed consumption, and mortality were recorded for 33 weeks. Molt treatments produced few significant differences; nonmolted control hens had overall poor performance. Full feeding of the 15% guar meal diet caused a slow cessation and reinitiation of lay with acceptable lay performance. The 10% guar meal diet reduced livability. All recurring day, limited-feeding treatments conserved feed during the first 35 days of molt induction. The 3rd and 5th recurring day-feeding treatments were particularly effective and had acceptable lay performance and feed efficiency. Neither level of BWR nor type of PF-PL diet significantly affected postmolt performance. The 30% BWR-FR induced-molt method produced superior (but not significantly) postmolt lay performance.

Animals↗
PubMed2005

Comparisons of molting diets on skeletal quality and eggshell parameters in hens at the end of the second egg-laying cycle.

A study was conducted to evaluate skeletal quality and eggshell parameters of molted hens at the end of the second laying cycle. Sixty Single Comb White Leghorn hens were used for this study. There were 2 controls and 4 molting treatments: full-fed control 1 (82 wk old; FF1), full-fed control 2 (122 wk old; FF2), feed withdrawal (FW), 100% alfalfa (A100), 90% alfalfa/10% layer ration (A90), and 70% alfalfa/30% layer ration (A70). At the end of the second laying cycle (approximately 122 wk of age), hens were euthanized by CO2. Tibia and femur were collected. There were no differences in bone parameters between FF1 and FF2 (P > 0.05) hens. There were no differences in bone parameters among the different molting dietary treatments (P > 0.05). In the eggshell parameters, the FF2 hens exhibited heavier egg weights than the FF1 (P < 0.05), whereas the percentage shell and egg production of the FF1 birds were significantly higher than those of the FF2 birds. Shell weights of the FW and A90 birds were significantly heavier than that of the A100. The correlation analysis showed that overall bone parameters were negatively correlated with eggshell parameters. Bone parameters were highly correlated with each other. Shell weight, percentage shell, and shell thickness were positively correlated with each other, whereas egg weight was negatively correlated with percentage shell. These results suggest that age of hens and molting dietary treatments influence egg parameters, and eggshell formation is closely related to bone metabolism in laying hens.

Animal Feed↗
PubMed2004

[Modelling sensitivity, specificity and predictive values of hematuria testing using reagent sticks in the diagnosis of Schistosoma haematobium infection].

Since its recognition as an effective tool to identify Schistosoma haematobium infection, haematuria detection has been used in several large scale control programs. However, large variations in performance between age groups, gender, prevalence and areas were observed. Correlation between the degree of haematuria and the intensity of infection and between intensity of infection with age and/or gender could partly explained these variations. Other factors, such as the circadian cycles and day-to-day variations of haematuria and egg excretion, a concomitant presence of blood in urine for another reason than schistosomiasis and the intrinsic characteristics of the reagents strips also contribute to the observed variations. This study assessed the influence of age, gender and intensity of infection taken together on the performance of the diagnostic test by fitting logistic regression models. During a socio-economic study of schistosomiasis, carried out between 1989 and 1991 in a rice-growing area located in Mali, West Africa, haematuria was detected by reagent strips among 2,873 six-year-old and more subjects randomly chosen from 14 villages. The "gold standard" of infection was provided by the parasite egg counts. Laboratory quality controls were implemented. Observed sensitivities, specificities, positive and negative predictive values were calculated by the standard two-by-two tables. The influence of age, gender, intensity of infection, measured in a continuous scale, on these parameters were studied by fitting two logistic models. The first one modelled sensitivity and specificity The second one modelled predictive values. Goodness-of-fit tests were performed. Large variations in the observed values of sensitivities, specificities and predictive values by age and gender were observed. The best fitted model for sensitivity and specificity included infection status, age, gender, intensity and an age by gender interaction. For the predictive values, the best model included haematuria, age, and an haematuria by age interaction. Given the large variations in the performances across the covariates strata defined by cross-tabulation of the age/gender and intensity categories, this modelling approach provided a more realistic appraisal of the performances than using overall values obtained from a general two- by-two table. It allowed to assess the effect of the covariates of interest on the performances of the test and provided an adjustment of the performances on these covariates. The best fitted model was able to provide estimates of sensitivity for each age/gender stratum as a function of the intensity of infection, which could not be done by using the two-by-two table approach. A decrease in sensitivity adjusted for intensity of infection above 10 years of age among males is discussed. This modelling approach also uses all the information available and not only the data from the stratum of interest.

Adolescent↗
PubMed1994

Relationship between morphology and chromosomal constitution in human preimplantation embryo.

In in vitro fertilization (IVF) procedures, morphologic embryo grading is the sole criteria for selection of embryos transferable in utero. Cytogenetic analysis of preimplantation embryos was performed to investigate the relationship between chromosomal status and morphologic quality of preimplantation eggs. Aneuploidy was the most frequently observed abnormality. In addition, various types of aberrations such as polyploidy, haploidy, mosaicism, and fragmentation were also found. Our results, pooled with data drawn from previous reports, demonstrated the prognostic value of the embryo grading system as a means for eliminating chromosomally abnormal embryos. In contrast, data suggested that some aspects of the IVF process might be responsible for the occurrence of these abnormalities.

Aneuploidy↗
PubMed2006

Xenopus tropicalis oocytes: more than just a beautiful genome.

For more than 30 yr, Xenopus laevis has been the animal of choice for studying the biochemical regulation of the meiotic and early mitotic vertebrate cell cycles. Attracted by its diploid genome, several laboratories have begun using the similar, although evolutionarily distinct, frog Xenopus tropicalis for studies of vertebrate development. Comparisons between the two species indicate that their development is similar in most respects. Both frogs share many advantages, including their amenability to manipulation and their ability to produce large numbers of high-quality oocytes and eggs year round. In addition, X. tropicalis possesses several advantages that, when combined with its potential for genetic studies, makes it an attractive, complementary model for vertebrate developmental biology. In this chapter, we note some of these advantages and describe in detail techniques we have adapted for the study of meiosis in X. tropicalis.

Animals↗
PubMed1996

The significance of an early (premature) rise of plasma progesterone in in vitro fertilization cycles induced by a "long protocol" of gonadotropin releasing hormone analogue and human menopausal gonadotropins.

OBJECTIVE: Our purpose was to assess and clarify the mechanism of whether an early progesterone rise in cycles with gonadotropin-releasing hormone agonist (GnRH-a) is associated with an impairment of IVF outcome. METHODS: Seven hundred eighty-six cycles were induced with GnRH-a and human menopausal gonodotropin (hMG) ("long protocol"). Plasma progesterone (PP) levels on the day of human chorionic gonadotropin (hCG) administration were divided into three groups: < 0.9 ng/ml (Group A), 1-2 ng/ml (Group B), and > 2 ng/ml (Group C). We also analyzed the pregnancies achieved in our egg donation protocol in relation to the PP levels of each donor on the day of hCG administration. RESULTS: Group A involved 525 cycles, Group B had 223, and Group C had 38. The overall pregnancy rate per egg transfer was 19.2%, with the highest for Group A (22.3%), declining for Groups B (14.3%) and C (7.9%) (A = B = C; P < 0.005). The embryo implantation rate was found to be negatively correlated with the PP levels on the day of hCG administration. In contrast, there was an opposite trend between PP levels and the chance of conception in 30 pregnancies achieved by egg donation. CONCLUSION: Since premature luteinization is very unlikely to occur under the conditions of this study, our findings suggest that an early PP rise has a negative impact on endometrial receptivity but not on egg and embryo quality.

Adult↗
PubMed1976

Delayed ovulation and monozygotic twinning.

Aiming to show that delayed ovulation may induce MZ twinning, follicular maturation was induced in the rabbit by a small quantity of Pregnant Mare Serum Gonadotropin (16 UI four times): coitus, which induces ovulation in the rabbit, was delayed 60 hours after the last injection. From the 387 blastocysts obtained after this treatment, 6 (1.5%) were pairs of MZ twins, twinning being otherwise exceptional in the rabbit. Other anomalies were shown by the embryos, apparently related to a deficient quality of the eggs: high embryonic mortality (62% vs. 27% in controls) and chromosomal anomalies (20%) such as trisomies, triploidies, and chimaeras. The relation between MZ twinning, chromosomal anomalies, and embryonic mortality induced by delayed ovulation, could be connected and related to the poor perinatal conditions frequently observed in human MZ twins.

Animals↗
PubMed2001

Utilisation of different phosphorus sources in relation to their fluorine content for broilers and layers.

1. The relative utilisation of different phosphorus sources in relation to their fluorine (F) content was studied in commercial broilers (5 to 40 d) and White Leghorn layers (252 to 364 d). The phosphorus (P) sources tested were bonemeal (BM), low fluorine (LFRP) and high fluorine (HFRP) rock phosphates and a commercial mineral mixture (CMM). The P sources were incorporated in broiler and layer diets by replacing dicalcium phosphate (DCP) on a P basis. 2. The F contents of diets based on BM, LFRP, CMM and HFRP were 53, 365, 622 and 1383 mg/kg in the broiler experiment and 34, 242, 437 and 967 mg/kg in the layer experiment, respectively. F was not detected in DCP based diets. 3. In broilers, body weight gain, food intake, gain: food, P retention and serum inorganic P content on P sources (BM and LFRP) containing F up to 365 mg/kg diet were similar to those on DCP. Body weight gain, food intake, serum calcium and inorganic P contents and retention of P were depressed in groups fed on CMM and HFRP, which may have been due to the toxic effects of F (622 and 1383 mg/kg) present in diets based on these P sources. 4. Bone ash and its P content were not affected by feeding diets containing F up to 1383 mg/kg from various P sources. The amount of F deposited in tibia increased significantly with increases in dietary F concentration. 5. In layers, egg production and food intake were not affected by F up to 437 mg/kg in diets containing BM, LFRP or CMM as the sole source of supplemental P. Egg production and food intake were depressed significantly in layers given the diet containing 967 mg F/kg from HFRP. 6. Egg mass: food, egg weight, shell quality (shell thickness and shell weight) and serum calcium and inorganic P levels were not affected by F up to 967 mg/kg in diets containing different P sources. 7. It may be concluded that the performance of broilers and layers was not affected by feeding various P supplements with dietary levels of F up to 365 and 437 mg/kg, respectively. The reduced performance in broilers and layers observed with some of the P sources may have been due to poor availability of P and/or toxic effects of F (622 and 967 mg/kg, respectively).

Animals↗
PubMed1986

Excessive cholecalciferol in a layers diet: decline in some aspects of reproductive performance and increased bone mineralisation of progeny.

Feeding hens a diet containing 5,000 micrograms (200,000 ICU)/kg of cholecalciferol for four 28-d periods had no adverse effect on hen-day egg production or hatchability. Egg weight, shell quality, food consumption and fertility were significantly decreased in hens fed 5,000 micrograms/kg. of cholecalciferol compared with those fed 24 micrograms (960 ICU) cholecalciferol/kg diet. Plasma calcium increased significantly as the concentration of cholecalciferol was increased in the diet. However, no histologically detectable changes in the viscera or changes in the proportion of bone ash were observed with any concentration of the vitamin. Chicks hatched from dams receiving excessive doses of cholecalciferol (5,000 micrograms/kg) and maintained on a rachitogenic diet for 4 weeks had a significantly higher proportion of tibial ash but there was no effect on either body weight or tibial calcium.

Animals↗
PubMed1999

Influence of supplemental microbial phytase on first cycle laying hens fed phosphorus-deficient diets from day one of age.

Pullets (19 wk of age) previously fed varying levels of aP (available P) with and without phytase (Natuphos) from Day 1 of age were used to determine the influence of 300 FTU phytase/kg diet on hen performance during Phase 1 (Week 21 to 36) and 2 (Week 37 to 48). At 19 wk of age, pullets were switched from developer diets to layer diets. The aP levels used in this portion of the study remained at 0.1, 0.2, 0.3, and 0.4% with and without phytase. These were the same levels fed in the starter and developer diets. Feed consumption, egg production, egg weight, egg specific gravity, and mortality were the criteria used. Reduction of aP from 0.4 to 0.2% had no effect on feed intake, egg production, egg weight, or eggshell quality (P > 0.05). However, hens fed 0.1% aP showed reduced feed intake, egg production, and bone mineral density (P < 0.001) and increased mortality (P < 0.001), but 300 FTU/kg phytase supplementation completely prevented these deficiencies. Eggs from hens fed 0.2, 0.3 and 0.4% aP diets were heavier than those fed 0.1% aP. Interactions between aP and phytase for feed consumption (P < 0.003), egg production (P < 0.001), and egg weight (P < 0.04) indicated that phytase corrected all deficiency symptoms in hens consuming 0.1% aP but showed no influence on hens fed aP levels > 0.2%. During Phase 2, aP by phytase interactions for feed consumption and egg production demonstrated that dietary phytase-corrected reductions related to P deficiency in hens consuming 0.2% aP. Results indicate that the addition of phytase in pullet diets from Day 1 of age through the first lay cycle can prevent reductions in performance of pullets fed low P diets.

6-Phytase↗
PubMed2006

Effects of induced molting on the well-being of egg-laying hens.

Induced molting in egg-laying hens is an important method for maximizing hen egg production and quality as well as hen health in commercial settings; however, there is growing societal concern over its effects on hen well-being. Using individual hens as their own controls, this research examined the behavior of hens subjected to different treatments of induced molting under premolt, molt, and postmolt conditions. Cage pecking increased in fast-induced subjects and aggression increased in fast-induced and nonfast-induced subjects during the molt. Gakel calling and several aspects of its acoustic structure were much higher during the molt condition in fast-induced subjects only. These data suggest that nonfast-induced molting treatments provide an effective method for inducing molting in hens and improving their well-being by minimizing discomfort due to food deprivation. In addition, these data further support that gakel vocalizations in hens may serve as an effective indicator for assessing well-being in a species otherwise behaviorally stoic in expressing stress or discomfort.

Animal Welfare↗
PubMed1995

Reduced dietary phosphorus levels for layers.

Two experiments were undertaken to study the response of White Leghorn hens to low dietary phosphorus levels from 18 to 64 wk of age. A corn-soybean meal diet containing .2% available phosphorus gave similar performance, up to 32 wk of age, as a similar control diet containing .4% available phosphorus. Beyond 32 wk, although shell quality and average egg weight were similar, egg production was significantly reduced with the lower phosphorus diet. Phosphorus excretion (grams per bird per day) averaged .47 g for .4% vs .28 g for .2% available phosphorus when measured at 28 wk of age. In a second experiment identical procedures and bird number as used in Experiment 1 were employed with the exception that the test diet contained .3% rather than .2% available phosphorus. No differences were noted for any of the production variables measured between the .4 and .3% available phosphorus diets. Phosphorus excretion data collected at 25, 32, 44, and 60 wk of age showed a decrease of approximately 20% for hens receiving the lower phosphorus diet. Indeed the overall average for phosphorus excretion for the lower phosphorus diet was calculated to be identical to the 20% lower total phosphorus content of this diet (.59 vs .47%).

Aging↗
PubMedDate not supplied

Chicken embryo lethality assay for determining the virulence of avian Escherichia coli isolates.

Multiple isolates of Escherichia coli from clinical cases of colibacillosis and E. coli from the intestinal tracts of normal broilers at slaughter were assayed by the embryo lethality test to determine their virulence. The assay was repeated five times in order to establish reproducibility and determine the statistical parameters of the test. This study showed that the inoculation of approximately 100 colony-forming units in the allantoic cavity of 12-day-old embryos discriminated between virulent and avirulent E. coli isolates. Gross lesions included cranial and skin hemorrhages in addition to encephalomalacia in embryos inoculated with virulent isolates. Abnormalities were observed by microscopic examination of the heart, brain, and liver in embryos inoculated with virulent isolates. Analysis of data indicated that the length of the test should be 4 days. In the virulent group, day 2 postinoculation had the most significant death patterns. Sample size calculations indicated that 11 embryos are sufficient for the assay. On the basis of death rates, isolates considered to be avirulent had an embryo death rate of <10%, moderately or secondary pathogens had a 10%-29% death rate, and virulent isolates had a death rate of >29%. An important aspect of this assay is the accessibility of good-quality fertile embryonated eggs.

Animals↗
PubMedDate not supplied

[Comparison of the effects of gonadotropic preparations of the carp and stellate sturgeon pituitaries on in vivo and in vitro oocyte maturation in the Siberian sturgeon Acipenser baeri brandt].

Injections of 2.5 mg/kg of stellate sturgeon (Acipenser stellatus Pall.) pituitary extract and 5 mg/kg of carp (Cyprinus carpio L.) pituitary extract in Siberian sturgeon (Acipenser baeri Brandt) females did not reveal significant differences in the effects of these preparations. There were no differences in the percentage of females that responded by ovulation, duration of the period from injection to ovulation, rate of ovulation, or quality of mature eggs as estimated by the percentage of fertilization or percentage of normal embryos at the small yolk plug stage. Thus, an insufficient efficiency in the artificial reproduction of the Siberian sturgeon grown in captivity is not related to the use of the carp pituitary preparation as a stimulus. Estimation of the ratio of specific activities of the pituitary extracts and purified gonadotropins of the stellate sturgeon and carp by in vitro oocyte maturation has shown that it varies within wide limits as a function of the medium composition and physiological state of follicles. Hence, the ratio of activities of the gonadotropins of different species as determined by in vitro maturation of sturgeon oocytes may markedly differ from that upon injection of these preparations in breeders.

Animals↗