Recent developments in the roles of vitamins and minerals in reproduction

The role of beta-carotene in cattle infertility, mastitis and milk yield: A systematic review and meta-analysis

The impact of beta-carotene on cattle fertility has been investigated in various studies; however, consensus on this issue has not been reached. In the present study, we systematically reviewed and meta-analysed 29 publications conducted between 1984 and 2022, focusing on seven fertility measures, clinical mastitis and milk yield in cows. We did not find statistically significant results in 8 out of 11 parameters (p > .05). Statistically significant results were observed for milk yield (MD: 216.25 kg in 305 days, p = .01, CI: 50.73-381.77), pregnancy at first service (OR: 1.38 CI: 1.08-1.76, p = .01) and clinical mastitis (OR: 0.59, CI: 0.44-0.80, p = .006) in favour of beta-carotene supplementation. The meta-regression revealed significant effects of 'plasma beta-carotene levels' on 'service to per pregnancy' and dose on 'milk yield' (p = .04 and p = 0). In binary outcomes, 'dose × day' and 'plasma beta-carotene concentration in the control group' positively influenced pregnancy at first service (p = .02 and .03). In conclusion, given the positive point direction observed for some variables and insignificant results for others, there is a need for more studies. We note the very high heterogeneity of outcomes and suggest caution in interpreting results.

Current Advances in Bovine In Vitro Maturation and Embryo Production Using Different Antioxidants: A Review

In vitro maturation (IVM) is one of the most important steps in in vitro embryo production (IVEP). It is a complicated procedure in which nuclear and cytoplasmatic changes in oocytes appear. In order to carry out the in vitro maturation procedure correctly, it is necessary to provide the oocytes with as close to a natural (in vivo) environment as possible. Many factors contribute to the overall poor quality of in vitro-matured oocytes. One important factor may be oxidative stress (OS). The generation of oxidants, such as reactive oxygen species, is common under culture conditions. The solution for OC treatment and prevention is antioxidants. In the last 5 years, many studies have examined different antioxidants and their effects on in vitro maturation of oocytes and embryo production. The aim of this systematic review was to present the achievements of scientific research in the last five years, in which the effects of many antioxidants were tested on bovine oocyte maturation and embryo production.

Effect of different sources of dietary zinc on sperm quality and oxidative parameters

Zinc has a critical physiological role in sperm function. The purpose of this study was to investigate the effect of different sources of zinc on sperm quality. For this purpose, 18 Zandi lambs with an average weight of 32 ± 1.2 kg were subjected to three treatments in a completely randomized design. Experimental treatments include (1) control treatment of basal diet without zinc supplementation, (2) basal diet with 40 mg/kg of zinc supplementation from zinc sulfate source and (3) basal diet with 40 mg/kg of zinc supplementation with organic source. At the end of feeding period, lambs were slaughtered. To determine the effect of experimental treatments on sperm quality, the testes were transferred to the laboratory. After that, epididymal spermatozoa were evaluated for sperm motility parameters, abnormal morphology, viability, membrane functionality, malondialdehyde (MDA) and antioxidant activity [glutathione peroxidase (GPx), superoxide dismutase (SOD), total antioxidant capacity (TAC)], sperm concentration and testosterone level. Zinc sulfate administration decreased MDA levels compared to other treatments and increased GPx and TAC activity compared to the control (P < 0.05), although SOD activity was not affected by any supplementation. Also, the use of zinc sulfate supplementation increased the percentage of total and progressive motility compared to the control group (P < 0.05). Membrane integrity and sperm viability were also affected by zinc sulfate supplementation (P < 0.05). Therefore, the results of this study showed that the use of zinc sulfate, can improve sperm motility and survival indices and its antioxidant capacity.

Comparative analysis of biochemical, hormonal, and mineral compositions of preovulatory and cystic ovarian follicles in buffalo during the non-breeding season

This study is a comparative analysis of the biochemical, hormonal, and mineral compositions of follicular fluid in preovulatory and cystic follicles of water buffalo (Bubalus bubalis). In total, reproductive tracts from 215 buffalo along with intact ovaries were collected randomly from an abattoir. The incidence of cystic conditions found in this study was 3.72% (8/215), involving the right ovary in 62.5% of instances and the left ovary in 37.5% of instances during the non-breeding season. Follicular fluid was aspirated from preovulatory follicles (12-15 mm diameter, oestrogen-active, follicular phase or stage IV corpus luteum on one of the two ovaries, n = 10) and cystic follicles (at least 20 mm diameter, no corpus luteum on any one of the two ovaries, n = 8). The follicular fluid samples were assayed for biochemical components (uric acid, creatinine, blood urea nitrogen, cholesterol, total protein, glucose, ascorbic acid, and alkaline phosphatase), hormones (progesterone, estradiol, and insulin), and minerals (calcium, magnesium, phosphorus, copper, zinc, and cobalt). Cystic follicles had greater (P < 0.05) concentrations of creatinine, blood urea nitrogen, cholesterol, progesterone, copper, zinc, and cobalt, and lesser (P < 0.05) concentrations of uric acid, glucose, ascorbic acid, estradiol, insulin, calcium, magnesium, and phosphorus compared with preovulatory follicles. These results indicated the marked differences in follicular fluid composition between preovulatory and cystic follicles in buffalo. Some of the changes were indicative of oxidative stress and disturbed steroidogenesis, two important mechanisms shown to be associated with cystic ovarian disease in various species. Further studies are warranted to investigate whether these differences are directly or indirectly involved in the formation of cystic follicles or are mere manifestations of the condition.

Effects of different vitamin A supplies on performance and the risk of ketosis in transition cows

This experiment investigated the effects of feeding low and high supplies of vitamin A (VA) during the transition period on plasma metabolites, prevalence of ketosis, and early milk production. In a randomized complete block design, 42 prefresh Holstein cows and 21 heifers were blocked by parity and calving date and assigned to 1 of 3 dietary treatments (n = 21 per treatment unless noted): CON, a transition diet with supplemental VA (75,000 IU/d) to meet the requirement; LVA, a transition diet with no supplemental VA; or HVA, a transition diet receiving supplemental VA (187,500 IU/d) 2.5 times greater than the requirement. Experimental periods were prepartum (-14 d prepartum), postpartum (1 to 30 d in milk), and carryover period (31 to 58 d in milk; common lactating diet with adequate VA was fed). Differences in dry matter intake in the pre- and postpartum periods and milk yield were not detected among treatment. Milk fat, protein, and lactose yields were similar among treatments and not affected by VA. Somatic cell count increased linearly with increasing VA. Body weight and body condition score decreased postpartum, but no VA effect was observed. Plasma retinol concentrations (n = 10 per treatment) decreased at d 2 postpartum and increased as lactation progressed, but the concentrations were unaffected by treatment. Plasma β-carotene (n = 10 per treatment) had a treatment by time interaction and its concentration decreased after parturition and remained low for 2 wk. Plasma fatty acids and β-hydroxybutyrate did not differ among treatments. Milk retinol concentration and yield (n = 10 per treatment) increased as VA supply increased. Segmented neutrophils (%) decreased, and lymphocytes (%) increased in blood with increasing VA supply. In conclusion, providing different supplies of VA did not affect production, mobilization of body fat, and risk of ketosis; however, excessive VA supply may have negatively affected the immune response, in part contributing to increased milk somatic cell counts during early lactation.

Carotenoids in female and male reproduction

Carotenoids are among the best-known pigments in nature, confer color to plants and animals, and are mainly derived from photosynthetic bacteria, fungi, algae, plants. Mammals cannot synthesize carotenoids. Carotenoids' source is only alimentary and after their assumption, they are mainly converted in retinal, retinol and retinoic acid, collectively known also as pro-vitamins and vitamin A, which play an essential role in tissue growth and regulate different aspects of the reproductive functions. However, their mechanisms of action and potential therapeutic effects are still unclear. This review aims to clarify the role of carotenoids in the male and female reproductive functions in species of veterinary interest. In female, carotenoids and their derivatives regulate not only folliculogenesis and oogenesis but also steroidogenesis. Moreover, they improve fertility by decreasing the risk of embryonic mortality. In male, retinol and retinoic acids activate molecular pathways related to spermatogenesis. Deficiencies of these vitamins have been correlated with degeneration of testis parenchyma with consequent absence of the mature sperm. Carotenoids have also been considered anti-antioxidants as they ameliorate the effect of free radicals. The mechanisms of action seem to be exerted by activating Kit and Stra8 pathways in both female and male. In conclusion, carotenoids have potentially beneficial effects for ameliorating ovarian and testes function.

Seasonal dynamic of cholecalciferol (D3) and anti-Muellerian hormone (AMH) with impact on ovarian response and IVF/ICSI

OBJECTIVE

Recent studies revealed intriguing associations between cholecalciferol (D3) and reproductive functions. Seasonal changes of D3 concentrations are well known; however, they are not always considered in the context of reproductive functions. In this study, we analyzed D3 serum concentration in IVF/ICSI patients with respect to seasonal 3-month quartiles and anti-Muellerian hormone (AMH) referring to the impact on Assisted Reproductive Technologies (ART) outcome.

MATERIALS AND RESEARCH METHODS

We studied 469 female patients, presenting between 2012 and 2018 for ART treatment in our fertility center. D3 as well as the AMH serum concentrations were measured at the beginning of the follicle stimulation (days 3-5 of menstrual cycles). Results were evaluated with respect to seasonal quartiles and outcome of the ART cycles.

RESULTS

D3 concentrations showed significant fluctuations within annual quartiles with a pronounced peak in August-October and a minimum in February-April (26.0 vs. 20.5 mg/dl; p < 0.0001). Similar seasonal dynamics were found for AMH (2.98 vs. 1.78 ng/ml; p = 0.010) and these were associated with significantly shorter stimulation periods during August-October (11.29 vs. 12.12 days; p = 0.042), higher number of fertilized oocytes between August and October (6.23 vs. 4.97; p = 0.05) along with a trend towards higher numbers of cumulus-oocyte complexes. However, no such differences were found for the numbers of MII oocytes or pregnancy rates.

CONCLUSION

Our data indicate seasonal 3-month quartile variations of AMH concentrations and characteristics of ART, such as days of ovarian stimulation and number of fertilized oocytes. Highest AMH concentrations were found between August and October and this quartile was associated with highest D3 concentrations.

The level of vitamin D in follicular fluid and ovarian reserve in an in vitro fertilization program: A pilot study

BACKGROUND

The level of vitamin D in follicular fluid (FF) according to the ovarian reserve has never been investigated, and the effect of FF vitamin D on the outcome of assisted reproductive technology (ART) remains controversial. The aim of this study is to evaluate the association between FF vitamin D levels and baseline anti-Müllerian hormone (AMH) / ART outcomes.

METHODS

Forty-seven patients who underwent controlled ovarian stimulation at the fertility clinic of an academic tertiary care center were enrolled for a prospective observational study. FF was collected from the first aspirated leading follicle of each ovary and assayed by an enzyme-linked immunosorbent assay. Multivariable linear regression analysis was used to assess the association between baseline AMH and FF vitamin D levels with adjustment for basal FSH and serum vitamin D levels.

RESULTS

Both the AMH and serum vitamin D were significant predictors for FF vitamin D. The estimated marginal mean of FF vitamin D level was higher in women with decreased ovarian reserve (DOR) than those with normal ovarian reserve (24.1 ± 2.1 vs. 18.8 ± 1.4 ng/ml, p = 0.048). However, FF vitamin D did not demonstrate any significant associations with cycle outcomes, including fertilization rate and the number and proportion of good embryos at day three.

CONCLUSION

We observed significantly higher FF vitamin D levels in women with DOR. However, FF vitamin D did not demonstrate any significant associations with the outcome of ART. A larger prospective study is needed to investigate the effect of FF vitamin D on the clinical pregnancy rate and live birth rate.

Effects of prepartum supplementation of β-carotene in Holstein cows

Whether supplemental dietary β-carotene affects periparturient cows and vitamins A and E in cows when dietary vitamin A is adequate remains uncertain. Our objective was to assess the effect of β-carotene supplementation during the close-up dry period in a herd with adequate status of vitamins A and E but low in β-carotene. The study was conducted on a large commercial dairy farm in Indiana during early summer of 2015. Ninety-four multiparous Holstein cows were assigned to either control (CON; n = 47) or β-carotene (BC; n = 47) treatments. When locked in headgates each morning, each cow received a topdress of β-carotene (Rovimix, 8 g/d; provided 800 mg of β-carotene) or carrier from 21 d before expected calving until calving. Blood samples were collected at 21 ± 1 d (mean ± standard deviation) before expected calving (before treatments began), 7 ± 1 d before calving, immediately following parturition, and 7 ± 1 d postpartum. Blood serum was analyzed for vitamins A and E, β-carotene, cholesterol, and other metabolites and enzymes. Data were analyzed using the MIXED procedure in SAS (SAS Institute Inc.). Cows had low β-carotene concentrations (0.85 μg/mL) in blood serum before treatments began. Compared with CON cows, BC cows had higher overall mean concentrations of β-carotene (2.87 μg/mL vs. 0.73 μg/mL) and retinol (165 vs. 143 ng/mL). Cows fed BC had lower α-tocopherol in serum than cows fed CON (2.26 vs. 2.46 µg/mL). Cows fed BC had lower peak milk than cows fed CON (50.9 vs. 55.3), but total lactation milk yield did not differ significantly. No effects of BC were observed on days to conception (100 d) or times bred (2.4). Treatments did not affect incidences of ketosis, retained placenta, displaced abomasum, off feed, lameness, footrot, mastitis, or metritis. In conclusion, in pregnant cows already receiving adequate vitamin A but with low serum β-carotene concentration, supplementation of β-carotene increased concentrations of β-carotene and vitamin A in blood serum, but did not affect production, reproduction, or health.

The effects of differing nutritional levels and body condition score on scrotal circumference, motility, and morphology of bovine sperm

Bulls often experience various levels of nutrient availability throughout the year. Nutritional management is a critical factor on overall ejaculate composition and the ability to get females pregnant. We hypothesized that differing nutritional levels and body condition score (BCS) affect reproductive fertility parameters in bulls. Mature Angus bulls (n = 11) were individually housed and randomly assigned to one of two dietary regimens: 1) over-fed (n = 5) or 2) restricted (n = 6). Bulls were fed the same ration at different volumes to achieve desired effects resulting in eight individual treatments: gain to an over-fed body condition score ([BCS]; GO), gain after nutrient restriction (GR), loss after an over-fed BCS (LO), loss from nutrient restriction (LR), maintenance at ideal adiposity (BCS = 6) after overfeeding (IMO), maintenance at ideal adiposity after nutrient restriction (IMR), maintenance at an over-fed BCS (BCS = 8; MO), and maintenance at a restricted BCS (BCS = 4; MR). Body weight (BW) and BCS were recorded every 2 wk to monitor bull weight and BCS changes. Scrotal circumference was measured every 28 d. Body fat and sperm motility and morphology were evaluated every 84 d. Scrotal circumference, motility, and morphology were normalized to the initial value of each bull. Thus, allowing the individual bull to serve as a control. Statistical analyses were conducted with PROC GLIMMIX of SAS as a complete randomized design to determine if treatment influenced BW, BCS, scrotal circumference, motility, morphology, and adipose thickness. Scrotal circumference (P < 0.001) had the least amount of deviation from initial during the LR (0.29 ± 0.44) treatment and the greatest during the MO (3.06 ± 0.44), LO (2.28 ± 0.44), MR (2.43 ± 0.44), GR (3.03 ± 0.44), and IMR (2.91 ± 0.44) treatments. Sperm motility was not affected by nutritional treatments (P = 0.55). Both head and total defects of sperm differed (P = 0.02) due to nutritional treatments. Increased head abnormalities occurred during the LO (37.60 ± 8.61) treatment, with no differences between the other treatments. Total defects increased during the LO (43.80 ± 9.55) treatment with similar increases in bulls during the GR (29.40 ± 9.55) and IMR (35.60 ± 9.55) treatments. In conclusion, male fertility was impacted when a deviation from a BCS of 6 occurred which could be detrimental to reproductive and beef production efficiency.

Reproductive Management of Rams and Ram Lambs during the Pre-Breeding Season in US Sheep Farms

Simple Summary

Pre-breeding management of rams and their ram lambs is critical for viable, sustainable and profitable farms. A further understanding of the management and selection criteria of the males during pre-breeding enables producers to efficiently use animal resources to maximize the reproductive potential of the animals. The reproductive management of mature rams and their lambs is complex, varying across breeds, farms, and regions of the world. It involves different aspects of animal husbandry, such as genetics, health, nutrition, behavior, economy and physiological and anatomical changes during the non-breeding season. Sound flock management must include an integrative and complete management plan for males and females that provides adequate conditions for the sheep to express their genetic potential and production level. This review article examines some of the key aspects to consider when managing mature rams and ram lambs during the pre-breeding season to ensure proper condition of the males for optimal function during the breeding season.

Abstract

In sheep farms, achieving economic and productive efficiency and sustainability goals is directly related with the reproductive management of the animals. Genetically, the male contribution to the offspring is 50%, but in practical terms, there is a greater potential impact of the ram on reproductive results, because one male has the potential to affect a large group of females and therefore greatly affects the entire flock. Unfortunately, the selection of males for breeding in the US sheep industry has been traditionally conducted based on phenotypical traits, without a genetic/reproductive evaluation, and/or health assessment or records. Therefore, it is important to establish integrative management practices to select the rams and ram lambs to be used in the breeding season. Among these practices are genomic testing, a comprehensive breeding soundness evaluation and assessment of health status and records of the males before the breeding season, to detect and correct potential issues.

Effects of feeding high volumes of milk replacer on reproductive performance and on concentrations of metabolites and hormones in blood of Japanese black heifer calves

We evaluated the effects of feeding high volumes of milk replacer on growth and reproductive performances in Japanese black heifers. Fifty-one heifers were fed milk replacer at 9 L/day for 60 days (9 L × 60 days; n = 18) or 41 days (9 L × 41 days; n = 15), or at 7 L/day for 40 days (7 L × 40 days; n = 18). Artificial insemination (AI) was performed on heifers with ≥270 kg body weight and ≥116 cm body height at 300 days of age. The age at the first AI was 0.35 month later for 7 L × 40 days than the other groups (p < .01). However, age at calving did not differ among treatments (22.1 months). The interval from the first AI to pregnancy tended to be ~2 months longer for the 9 L × 60 days than the other groups (p = .07). Our results showed that feeding high volumes of milk replacer may reduce the age at calving via an improved rate of growth. In addition, we propose that feeding a maximum of 7 L milk replacer for 40 days may be the most appropriate rearing regime because the success of pregnancy per AI may be reduced in calves fed a maximum of 9 L for 41 and 60 days.

Carotenoid, Tocopherol, and Phenolic Compound Content and Composition in Cover Crops Used as Forage

Secondary compounds of grassland and forage plant species such as vitamins or phenolic compounds are involved in different health-promoting effects in animals. However, information on their concentration and composition in forage plant species remains scarce. The objective of this study was to characterize the composition of secondary compounds of seven grazed cover crop plant species harvested at two stages of growth. Carotenoids and tocopherols were characterized and quantified using ultraperformance liquid chromatography with a photodiode array, and soluble phenolic compounds were characterized using high-performance liquid chromatography with diode-array detection. All species were rich in carotenoids, especially at the vegetative stage, even if the concentrations varied between plant species. Variations in tocopherol concentrations and phenolic composition were more important between plant species than between stages within species. Among the plant species tested, sainfoin (Onobrychis viciifolia Scop) contained the most secondary metabolites.

The Association between Vitamin D and Anti-Müllerian Hormone: A Systematic Review and Meta-Analysis

Accumulating evidence from animal and human studies indicates a role for vitamin D in female reproductive physiology, and numerous clinical studies have suggested its potential benefit for various aspects of human reproduction. Anti-Müllerian hormone (AMH) is an ovarian biomarker that plays an important role in folliculogenesis. It is the most sensitive ovarian reserve marker and is widely used clinically in reproductive medicine. While initial studies have suggested that vitamin D may be associated with ovarian reserve markers, including AMH, evidence has been conflicting. Currently, there is considerable debate in the field whether vitamin D has the capacity to influence ovarian reserve, as indicated by the AMH level. The current systematic review aims to evaluate and summarize the available evidence regarding the relationship between vitamin D and AMH. In total, 18 observational studies and 6 interventional studies were included in this systematic review. Cross-sectional studies have reported largely discrepant findings regarding an association between serum vitamin D and AMH levels, which are likely due to the heterogeneity in study populations, as well as the apparently complex relationship that may exist between vitamin D and AMH. However, meta-analysis of interventional studies performed herein that examined the effects of vitamin D supplementation on serum AMH levels indicates a cause-effect relationship between vitamin D and AMH, the direction of which appears to depend on a woman’s ovulatory status. Serum AMH was significantly decreased following vitamin D supplementation in polycystic ovarian syndrome (PCOS) women (standardized mean difference (SMD) −0.53, 95% CI −0.91 to −0.15, p < 0.007), while it was significantly increased following vitamin D supplementation in ovulatory women without PCOS (SMD 0.49, 95% CI 0.17 to 0.80, p = 0.003). In conclusion, the results of this systematic review demonstrate that the relationship between vitamin D and AMH is a complex one, and large, randomized trials of vitamin D supplementation focusing on different vitamin D status ranges are necessary to gain more insight into the nature of this relationship and the potential benefit of vitamin D to female reproduction in general.

Breeding animals to feed people: The many roles of animal reproduction in ensuring global food security

As the population grows and shifts demographically, the resulting increase in demand for beef and milk necessitates improvements in the sustainability of ruminant livestock production systems. Ruminant livestock contribute to ensuring global food security because they have the ability to up-cycle non-human-edible products into meat and milk products with notable nutritional value. However, ruminant livestock also pose a challenge to global food sustainability because they are resource-intensive to produce and contribute substantially to agricultural greenhouse gas emissions. As such, improving environmental impacts of ruminant livestock production globally is an essential goal. There are a number of strategies that can be employed to enhance sustainability of ruminant production systems; however, improving reproductive efficiency is among the more efficient, because an increase in reproductive success will reduce the number of cows needed to produce a target quantity of beef. This reduction in the cow herd size helps limit the number of unproductive animals retained in the herd, thereby reducing the environmental maintenance cost of livestock production. Additionally, proper application of reproductive technologies enables faster and more targeted advances in genetic gains, which can be leveraged to produce phenotypes that are resource-use-efficient and well-adapted to their production environment. Optimizing reproductive efficiency can be accomplished through improved genetic selection for fertility and fecundity; applying more effective use of assisted reproductive technologies; and coupling reproductive and nutritional management to optimize likelihood of reproductive success. Collectively, applying these approaches will be essential when working to ensure ruminant livestock's contribution to global food security.

Reproductive performance in goats and causes of perinatal mortality: a review

Goat meat production is an expanding industry in Australia. However, there is limited data quantifying the levels of reproductive performance, particularly under extensively grazed rangeland conditions, which would inform interventions to improve performance. This review aimed to quantify the levels of reproduction, time and causes of reproductive wastage in goats. It considers the levels of fertility, fecundity, embryonic loss, fetal loss and post-natal survival reported under Australian conditions, and comparisons are made with international reports. Key management factors that may contribute to reproductive performance include breed, seasonality, nutritional conditions, and weather conditions at kidding. While goats are potentially prolific breeders, in Australia, the variation in weaning rate (kids/doe joined) among properties is large (51–165%), although the causes of this variation are not well defined. Generally, conception and kidding rates are high, although fetal loss associated with undernutrition is more likely in goats than sheep. As with sheep, perinatal losses are generally the largest source of wastage, with an average 20% kid mortality, but this level is influenced by litter size and appears to be higher under extensive rangeland systems. The causes of perinatal kid loss under Australian conditions are similar to those in sheep, with starvation–mismothering–exposure and dystocia or stillbirth the key causes. Studies are needed to accurately quantify the level and causes of reproductive wastage in commercial herds, including a range of management situations, to enable effective interventions to be developed.

The Role of Zinc in Poultry Breeder and Hen Nutrition: an Update

Zinc (Zn) is an essential trace mineral in breeder hen diets and functions in diverse physiological processes, including reproduction, immunity, antioxidant ability, and epigenetic processes. In this paper, five main aspects of Zn nutrition in poultry breeder birds and hens, including semen quality, molting, egg production and egg quality, hatchability and embryonic development, and offspring performance, are reviewed. Zn deficiency in poultry breeder birds led to lower semen quality (reducing around 10% sperm motility) and egg production (lowering 3-10 g/day/bird egg mass) as well as poor offspring development and growth performance (increasing 9-10% weak chick ratio and 10% mortality of progeny). Adequate maternal or higher Zn supplementation was adopted not only to induce molting with a greater postmolt performance (rising 4-7% laying rate) but also to enhance progeny immune response and antioxidant ability via epigenetic mechanisms. Therefore, it is necessary to reevaluate the optimal Zn requirement for egg production as well as the embryonic development and offspring chick performance of breeder hens. In the last 10 years, greater attention has been focused on the effectiveness of organic Zn for improving the reproductive performance of breeders and progeny viability and immune status. In fact, organic Zn sources are not always beneficial to the above aspects. So far, it has been very important to know the exact mechanisms of greater bioavailability and the epigenetic role of organic Zn sources in the augmentation of immune status and antioxidant abilities in poultry breeder birds and offspring. Therefore, a comprehensive analysis of these key points will not only aid in maintaining the beneficial effects of Zn nutrition for breeders and their progeny under stable conditions but will also support birds under stressful conditions such as disease as well as provide a better understanding of the integrated nutrition of breeder-offspring.

Synchronization with controlled internal drug release (CIDR) and prostaglandin F2α (PGF2α) influences oxidant/antioxidant biomarkers and mineral profile in summer-stressed anoestrous buffalo (Bubalus bubalis)

During the summer season, high ambient temperature in tropical and subtropical countries exposes buffaloes to oxidative stress that have antigonadotropic and antisteroidogenic effects. Uses of hormonal therapy can improve the state of ovarian inactivity caused by heat stress and cause anoestrous buffaloes to come into oestrus and successfully achieve pregnancy. Therefore, this study was designed to detect the role of oxidative stress in production of the anoestrous state in summer heat stressed buffaloes and the effects of treatment by Controlled internal drug release (CIDR) in solving of this problem. Also it monitored the changes in Oxidant/antioxidant biomarkers and mineral profile before and after the treatment. Forty buffaloes with no signs of oestrus for more than 120 days after calving were selected. The animals were divided into two groups: the first group (group I, n = 25) was subjected to treatment with CIDR, while the second group (group II) received no treatment and was considered the control group (n = 25). Blood samples were collected before treatment, after treatment and after 45 days of oestrus. The serum level of TAC, MDA, NO, ascorbic acid (vitamin C), P, Cu and Zn were measured. The results showed that 80% of treated buffaloes came into oestrus. The conception rate was 75%. TAC concentrations were significantly higher in group I than in group II. There were significant decreases in the mean values of MDA, NO and ascorbic acid in the buffaloes in oestrus, but these values increased when the buffaloes became pregnant. In contrast there were no significant differences in the mean values of MDA, NO or ascorbic acid in the buffaloes that came into oestrus but failed to conceive. The mean serum P, Cu and Zn values were significantly increased (P < 0.05) in the buffaloes that came into oestrus compared to the control animals. The levels of P and Zn significantly increased when the buffaloes became pregnant and remained unchanged when they failed to conceive. In conclusion, known physiological and pathological variations in the oxidant/antioxidant parameters and mineral profile of summer anoestrous buffaloes may help to understand this problem of infertility.

Effects of nutrition and genetics on fertility in dairy cows

Optimal reproductive function in dairy cattle is mandatory to maximise profits. Dairy production has progressively improved milk yields, but, until recently, the trend in reproductive performance has been the opposite. Nutrition, genetics, and epigenetics are important aspects affecting the reproductive performance of dairy cows. In terms of nutrition, the field has commonly fed high-energy diets to dairy cows during the 3 weeks before calving in an attempt to minimise postpartum metabolic upsets. However, in the recent years it has become clear that feeding high-energy diets during the dry period, especially as calving approaches, may be detrimental to cow health, or at least unnecessary because cows, at that time, have low energy requirements and sufficient intake capacity. After calving, dairy cows commonly experience a period of negative energy balance (NEB) characterised by low blood glucose and high non-esterified fatty acid (NEFA) concentrations. This has both direct and indirect effects on oocyte quality and survival. When oocytes are forced to depend highly on the use of energy resources derived from body reserves, mainly NEFA, their development is compromised due to a modification in mitochondrial β-oxidation. Furthermore, the indirect effect of NEB on reproduction is mediated by a hormonal (both metabolic and reproductive) environment. Some authors have attempted to overcome the NEB by providing the oocyte with external sources of energy via dietary fat. Conversely, fertility is affected by a large number of genes, each with small individual effects, and thus it is unlikely that the decline in reproductive function has been directly caused by genetic selection for milk yield per se. It is more likely that the decline is the consequence of a combination of homeorhetic mechanisms (giving priority to milk over other functions) and increased metabolic pressure (due to a shortage of nutrients) with increasing milk yields. Nevertheless, genetics is an important component of reproductive efficiency, and the incorporation of genomic information is allowing the detection of genetic defects, degree of inbreeding and specific single nucleotide polymorphisms directly associated with reproduction, providing pivotal information for genetic selection programs. Furthermore, focusing on improving bull fertility in gene selection programs may represent an interesting opportunity. Conversely, the reproductive function of a given cow depends on the interaction between her genetic background and her environment, which ultimately modulates gene expression. Among the mechanisms modulating gene expression, microRNAs (miRNAs) and epigenetics seem to be most relevant. Several miRNAs have been described to play active roles in both ovarian and testicular function, and epigenetic effects have been described as a consequence of the nutrient supply and hormonal signals to which the offspring was exposed at specific stages during development. For example, there are differences in the epigenome of cows born to heifers and those born to cows, and this epigenome seems to be sensitive to the availability of methyl donor compounds of the dam. Lastly, recent studies in other species have shown the relevance of paternal epigenetic marks, but this aspect has been, until now, largely overlooked in dairy cattle.

Vitamin A and Breast-Feeding: A Comparison of Data from Developed and Developing Countries

The vitamin A status of lactating women, its effect on the vitamin A content of human milk, and the adequacy of human milk as a source of vitamin A for the infant were assessed, comparing data from developing countries with those from developed countries. The vitamin A concentration in breast milk during the first two weeks of lactation is nearly double that at one month. It is even higher in preterm milk than in term milk during the first several months. Human milk alone provides sufficient vitamin A to prevent clinical deficiency throughout the first 12 months of life, even in presumably more poorly nourished populations in developing countries. However, it is not sufficient to allow liver storage after about six months of lactation.

Mineral status of California beef cattle

Optimal mineral nutrition is required for cattle reproduction, immune function, and structural development. Formal evaluation of the current mineral status of California beef cattle is currently lacking. In 2017, a survey was initiated that evaluated a panel of 10 different minerals in 14 counties across California. Samples were collected from 555 cattle at 50 different ranches. Region of the state significantly affected herd mineral status. Herd use of supplements was also significant, and increased most blood levels of the mineral(s) targeted for supplementation. Forage source was idiosyncratic on its effect of mineral status. Previous blood survey data showed selenium to be widely deficient in California cattle in the 1970s and 1980s, but in this case, it was generally adequate in all areas of California. This indicates a good producer understanding of where supplementation is needed. Copper deficiency was more widespread in the southern region when compared with further north. Zinc deficiency was seen ubiquitously statewide, with 36% of animals being deficient. Manganese has been largely ignored in California. This study is the first known documentation of manganese levels in the state. Sampling found 92% of cattle fell below critical manganese levels. However, further research to better define manganese critical levels is probably warranted. The status of other minerals is presented.

A 100-Year Review: From ascorbic acid to zinc-Mineral and vitamin nutrition of dairy cows

Mineral and vitamin nutrition of dairy cows was studied before the first volume of the Journal of Dairy Science was published and is still actively researched today. The initial studies on mineral nutrition of dairy cows were simple balance experiments (although the methods available at the time for measuring minerals were anything but simple). Output of Ca and P in feces, urine, and milk was subtracted from intake of Ca and P, and if values were negative it was often assumed that cows were lacking in the particular mineral. As analytical methods improved, more minerals were found to be required by dairy cows, and blood and tissue concentrations became primary response variables. Those measures often were poorly related to cow health, leading to the use of disease prevalence and immune function as a measure of mineral adequacy. As data were generated, mineral requirements became more accurate and included more sources of variation. In addition to milk yield and body weight inputs, bioavailability coefficients of minerals from different sources are used to formulate diets that can meet the needs of the cow without excessive excretion of minerals in manure, which negatively affects the environment. Milk, or more accurately the lack of milk in human diets, was central to the discovery of vitamins, but research into vitamin nutrition of cows developed slowly. For many decades bioassays were the only available method for measuring vitamin concentrations, which greatly limited research. The history of vitamin nutrition mirrors that of mineral nutrition. Among the first experiments conducted on vitamin nutrition of cows were those examining the factors affecting vitamin concentrations of milk. This was followed by determining the amount of vitamins needed to prevent deficiency diseases, which evolved into research to determine the amount of vitamins required to promote overall good health. The majority of research was conducted on vitamins A, D, and E because these vitamins have a dietary requirement, and clinical and marginal deficiencies became common as diets for cows changed from pasture and full exposure to the sun to stored forage and limited sun exposure. As researchers learned new functions of fat-soluble vitamins, requirements generally increased over time. Diets generally contain substantial amounts of B vitamins, and rumen bacteria can synthesize large quantities of many B vitamins; hence, research on water-soluble vitamins lagged behind. We now know that supplementation of specific water-soluble vitamins can enhance cow health and increase milk production in certain situations. Additional research is needed to define specific requirements for many water-soluble vitamins. Both mineral and vitamin research is hampered by the lack of sensitive biomarkers of status, but advanced molecular techniques may provide measures that respond to altered supply of minerals and vitamins and that are related to health or productive responses of the cow. The overall importance of proper mineral and vitamin nutrition is known, but as we discover new and more diverse functions, better supplementation strategies should lead to even better cow health and higher production.

Vitamin D is associated with bioavailability of androgens in eumenorrheic women with prior pregnancy loss

BACKGROUND

Prior studies have reported mixed results regarding relationships between vitamin D, androgens, and sex hormone-binding globulin in patients with polycystic ovary syndrome. However, less is known regarding these associations in eumenorrheic, premenopausal women.

OBJECTIVE

Our objective was to study the relationships between serum vitamin D and androgen biomarkers in eumenorrheic women with a history of pregnancy loss who were attempting pregnancy.

STUDY DESIGN

This was an analysis of a cohort of 1191 participants from the Effects of Aspirin in Gestation and Reproduction trial (2006-2012). Participants were attempting to conceive, aged 18-40 years, with 1-2 documented prior pregnancy losses and no history of infertility, and recruited from 4 academic medical centers in the United States. Serum vitamin D (25-hydroxyvitamin D) and hormone concentrations were measured at baseline.

RESULTS

Vitamin D concentration was negatively associated with free androgen index (percentage change [95% confidence interval, -5% (-8% to -2%)] per 10 ng/mL increase) and positively associated with sex hormone-binding globulin (95% confidence interval, 4% [2-7%]), although not with total testosterone, free testosterone, or dehydroepiandrosterone sulfate after adjusting for age, body mass index, smoking status, race, income, education, physical activity, and season of blood draw.

CONCLUSION

Overall, vitamin D was associated with sex hormone-binding globulin and free androgen index in eumenorrheic women with prior pregnancy loss, suggesting that vitamin D may play a role in the bioavailability of androgens in eumenorrheic women. We are limited in making assessments regarding directionality, given the cross-sectional nature of our study.

Whether vitamin D was associated with clinical outcome after IVF/ICSI: a systematic review and meta-analysis

BACKGROUND

There exist contradictive views on whether the vitamin D has association with clinical outcome of in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI). The present meta-analysis aim to establish whether vitamin D was associated with clinical outcomes of IVF/ICSI.

METHODS

MEDLINE, Google Scholar and the Cochrane Library from database inception to March 2017 were searched. Clinical studies, which evaluated the association of vitamin D level and the clinical outcomes after IVF/ICSI, were included. The Main Outcome Measures were clinical pregnancy, ongoing pregnancy, and live birth.

RESULTS

In the analysis of clinical pregnancy, 9 cohort studies were included. Of which, 2 studies and 3 studies were identified in analyzing ongoing pregnancy and live birth, respectively. Meta-analysis showed trends toward lower clinical pregnancy [RR 0.91, (95% CI 0.77-1.07)] and higher ongoing pregnancy [RR 1.06, (95% CI 0.95-1.19)] for women with deficient level of vitamin D. The probability of live birth for women with deficient level of vitamin D was significantly lower than cases with sufficient level of vitamin D [RR 0.74, (95% CI 0.58-0.90)].

CONCLUSIONS

Deficient vitamin D was associated with decreased probability of live birth after IVF/ICSI. So vitamin D should be supplied to women with deficient level vitamin D.

Reproductive management in dairy cows - the future

Background

Drivers of change in dairy herd health management include the significant increase in herd/farm size, quota removal (within Europe) and the increase in technologies to aid in dairy cow reproductive management.

Main body

There are a number of key areas for improving fertility management these include: i) handling of substantial volumes of data, ii) genetic selection (including improved phenotypes for use in breeding programmes), iii) nutritional management (including transition cow management), iv) control of infectious disease, v) reproductive management (and automated systems to improve reproductive management), vi) ovulation / oestrous synchronisation, vii) rapid diagnostics of reproductive status, and viii) management of male fertility. This review covers the current status and future outlook of many of these key factors that contribute to dairy cow herd health and reproductive performance.

Conclusions

In addition to improvements in genetic trends for fertility, numerous other future developments are likely in the near future. These include: i) development of new and novel fertility phenotypes that may be measurable in milk; ii) specific fertility genomic markers; iii) earlier and rapid pregnancy detection; iv) increased use of activity monitors; v) improved breeding protocols; vi) automated inline sensors for relevant phenotypes that become more affordable for farmers; and vii) capturing and mining multiple sources of “Big Data” available to dairy farmers. These should facilitate improved performance, health and fertility of dairy cows in the future.

Is immunosuppression, induced by neonatal thymectomy, compatible with poor reproductive performance in adult male rats?

With increasing knowledge that the immune system has a major impact on reproductive ‎health, the potential for cells arising in organs such as the thymus to alleviate oxidative stress ‎has been revealed. This study addresses the impact of neonatal thymectomy on male ‎reproductive function in pubertal and adult animals. Neonatal Sprague Dawley rats were allotted to four treatments consisting of fully thymectomized, partially thymectomized, intact, and sham-operated rats. Half of the rats in each treatment were sacrificed at 40 and the other half at 80 days of age. Testicular volume, ventral prostate and spleen weight, several sperm attributes (concentration, motility, livability, membrane integrity, sperm penetration into mucus, total antioxidant capacity, mitochondrial dehydrogenase activity), plasma superoxide dismutase, glutathione, and testosterone level as well as fertility decreased in thymectomized rats. Adrenal gland weight, sperm malondialdehyde level, indices of oxidative stress, sperm abnormality, testicular and sperm lipid peroxidation, protein carbonylation, and sperm reactive oxygen species generation increased in thymectomized rats. In thymectomized rats, the testes contained high levels of malondialdehyde but low levels of glutathione and ferric-reducing antioxidant power. Epididymal sperm reactive oxygen species, blood lipid peroxidation, and oxidative stress indices ‎‎in blood and spermatozoa were highest in fully thymectomized, intermediate ‎in partially thymectomized, and lowest in both pubertal and mature control rats. Blood levels of superoxide dismutase, lipid peroxidation indices, and ‎testosterone, and mitochondrial adenosine triphosphate and ‎dehydrogenase activities in epididymal spermatozoa were lowest in fully thymectomized, ‎intermediate in partially thymectomized, and highest in both pubertal and mature control rats.‎ The data indicated that increased oxidative stress and mitochondrial dysfunction might play a role in the mechanism of immunosuppression-induced testicular and sperm abnormalities.

Aflatoxin B1 Induced Systemic Toxicity in Poultry and Rescue Effects of Selenium and Zinc

Among many challenges, exposure to aflatoxins, particularly aflatoxin B₁ (AFB₁), is one of the major concerns in poultry industry. AFB₁ intoxication results in decreased meat/egg production, hepatotoxicity, nephrotoxicity, disturbance in gastrointestinal tract (GIT) and reproduction, immune suppression, and increased disease susceptibility. Selenium (Se) and zinc (Zn), in dietary supplementation, offer easy, cost-effective, and efficient ways to neutralize the toxic effect of AFB₁. In the current review, we discussed the impact of AFB₁ on poultry industry, its biotransformation, and organ-specific noxious effects, along with the action mechanism of AFB₁-induced toxicity. Moreover, we explained the biological and detoxifying roles of Se and Zn in avian species as well as the protection mechanism of these two trace elements. Ultimately, we discussed the use of Se and Zn supplementation against AFB₁-induced toxicity in poultry birds.

Vitamin D Deficiency Does Not Influence Reproductive Outcomes of IVF-ICSI: A Study of Oocyte Donors and Recipients

Background:

Vitamin D and its active metabolite, 1,25-dihydroxy vitamin D (1,25-(OH)₂D₃), play a significant role in reproduction.

Aim:

To assess the effect of serum 25-hydroxy vitamin D level on oocyte quality and endometrial receptivity by studying oocyte donors and their recipients.

Materials and Methods:

This prospective study consisted of two groups: Group A (recipient group) and Group B (donor group). All the participants of Groups A1 and B1 as well as Groups A2 and B2 were subcategorized into vitamin D-deficient (<20 ng/mL) and vitamin D replete-insufficient (20 to ≥30 ng/mL), respectively.

Results:

In the recipient group, out of the 192 participants, 123 were in A1 group, and 69 were in A2 group. In donor group, out of the 99 participants, 54 were in B1 group, and 45 in B2 group. In the recipient group, Group A2 had a higher clinical pregnancy rate, implantation rate and ongoing pregnancy rate, and a lower abortion rate as compared to that of A1, but these are statistically insignificant. The difference in endometrial thickness and number of embryos transferred between both groups was insignificant. In the donor group, the total number of days of controlled ovarian hyperstimulation, the dose of gonadotropins, the number of oocytes retrieved, the percentage of mature oocytes, and the percentage of usable embryos were higher in Group B2 than those in Group B1, but these are statistically insignificant. The fertilization rate was statistically insignificant between Groups B1 and B2.

Conclusion:

Vitamin D deficiency leads to lower reproductive outcomes, though not statistically significant and, thereby, does not have a negative influence on in-vitro fertilization–intracytoplasmic sperm injection outcomes.

Association between non-parturient post-partum hypocalcaemia and the interval from calving to first ovulation in Holstein-Friesian cows

This study was undertaken to quantify the effect of episodes of subclinical hypocalcaemia on the interval from calving to first ovulation. It incorporated three separate surveys during early lactation of 44 and 60 cows at Mutdapilly Research Station and 56 cows at Wollongbar Agricultural Institute. Twenty-five, 37 and 39% of cows respectively, experienced episodes later than 3 days after calving, of non-parturient post-partum hypocalcaemia, when plasma calcium concentration fell below 2⋅00 mmolll. Episodes of subclinical hypocalcaemia did not affect the interval to first post-partum ovulation in the two experiments conducted at Mutdapilly Research Station but ovulation was significantly delayed in cows that experienced episodes of subclinical hypocalcaemia at Wollongbar Agricultural Institute.

Serum selenium and liposoluble vitamins in Japanese Black cows that had stillborn calves

Stillbirth and dystocia are major factors that negatively affect beef production. We sought to clarify serum selenium and liposoluble vitamin levels in Japanese Black cows that gave birth to stillborn calves (stillbirth cows). Blood samples were collected from 103 stillbirth cows and 95 cows that gave birth to healthy calves (control cows). Serum levels of selenium (45.8 ± 16.0 ng/ml) and vitamin A (73.0 ± 24.8 IU/dl) in stillbirth cows were lower (P<0.05) than those in control cows (52.2 ± 8.9 ng/ml and 93.3 ± 14.8 IU/dl, respectively). Our findings suggest that appropriate serum selenium and vitamin A levels are important for calving cows.

Serum vitamin D status and in vitro fertilization outcomes: a systematic review and meta-analysis

OBJECTIVE

To assess the correlation between serum 25-hydroxy vitamin D [25(OH)D] status and outcomes of in vitro fertilization (IVF) in infertile women through review systematically.

METHODS

We used Embase, Pubmed, and Cochrane database to identify all studies that assessed the correlation between serum vitamin D levels and IVF outcomes in infertile women up until 30 June 2015, with the restricted language of English. We included studies that compared IVF outcomes between infertile women vitamin D <20 ng/ml and vitamin D ≥20 ng/ml. The results were summarized using Stata 12.0 software. For studies reported dichotomous outcomes (clinical pregnancy rate and live birth rate), we pooled the relative risks ratios (RRs) and 95 % confidence intervals (CIs) in a random effects model.

RESULTS

Our search resulted in the retrieval and screening of 134 studies. Of those, five studies were included in our meta-analysis. The risk for lower clinical pregnancy rate was not significantly increased in the deficient group (RR 0.88, 95 % CI 0.69-1.11). Lower vitamin D status was associated with lower live birth rate (RR 0.76, 95 % CI 0.61-0.93).

CONCLUSION

There is no significant correlation between deficient serum vitamin D level and lower clinical pregnancy rate in infertile woman undergoing in vitro fertilization. On the other hand, deficient vitamin D level was related to lower live birth rate.

Influence of hepatic load from far-off dry period to early postpartum period on the first postpartum ovulation and accompanying subsequent fertility in dairy cows

The aim of the present study was to investigate nutritional and metabolic parameters during the dry and early postpartum periods of ovulatory and anovulatory cows, as well as their postpartum reproductive performance. Blood samples from 20 multiparous Holstein cows were collected once a week from the far-off dry period to 3 weeks postpartum. Early postpartum (0–3 weeks) ovulation was confirmed using plasma progesterone concentration profiles, and cows were considered ovulatory if they had resumed luteal activity by this point (n = 9), whereas cows that had not were considered anovulatory (n = 11). Data from the ovulatory and anovulatory cows were analyzed separately for the far-off dry period (7–4 weeks prepartum), the close-up dry period (3–1 weeks prepartum), and the early postpartum period (0–3 weeks). Serum gamma-glutamyl transpeptidase activity (far-off, P = 0.065; close-up, P = 0.051; and early postpartum, P = 0.030) and aspartate aminotransferase (close-up, P = 0.050 and early postpartum, P = 0.087) activities were higher in anovulatory than in ovulatory cows. The days open period was longer (P = 0.019) in anovulatory than in ovulatory cows, and the number of artificial inseminations per conception (P = 0.025) was greater. In conclusion, we found that continuously high gamma-glutamyl transpeptidase activities in serum, which may be induced by liver disorders, prevent subsequent ovulation and affect subsequent fertility, even if cows obtain sufficient ovulation-related energy and β-carotene.

Role of vitamin D in ovarian physiology and its implication in reproduction: a systematic review

OBJECTIVE

To report an update on the role of vitamin D (VD) in ovarian physiology with a focus on genes involved in steroidogenesis, follicular development, and ovarian reserve, as well as ovulatory dysfunction associated with polycystic ovary syndrome (PCOS), and ovarian response to assisted reproductive technology (ART).

DESIGN

Systematic review.

SETTING

Not applicable.

PATIENT(S)

Human, animal, and cell culture models.

INTERVENTION(S)

Pubmed literature search.

MAIN OUTCOME MEASURE(S)

Granulosa cell function, serum antimüllerian hormone (AMH), AMH and its receptor gene expression, soluble receptor for advanced glycation end-products (sRAGE), PCOS parameters, and ART outcome.

RESULT(S)

In human granulosa cells, VD alters AMH signaling, FSH sensitivity, and progesterone production and release, indicating a possible physiologic role for VD in ovarian follicular development and luteinization. In the serum, 25-hydroxyvitamin D (25OH-D) is positively correlated with AMH, and appropriate VD supplementation in VD-depleted women can suppress the seasonal changes that occur in serum AMH. In VD-deficient women with PCOS, VD supplementation lowers the abnormally elevated serum AMH levels, possibly indicating a mechanism by which VD improves folliculogenesis. The antiinflammatory sRAGE serum levels significantly increase in women with PCOS after VD replacement. Although follicular fluid 25OH-D correlates with IVF outcomes, there is a lack of data pertaining to the impact of VD supplementation on pregnancy rates following IVF.

CONCLUSION(S)

This review underscores the need for understanding the mechanistic actions of VD in ovarian physiology and the critical need for randomized trials to elucidate the impact of VD supplementation on controlled ovarian hyperstimulation/IVF outcome and ovulatory dysfunction associated with PCOS.

Effects of sub-chronic aluminum chloride exposure on rat ovaries

AIMS

This experiment investigated the effects of sub-chronic aluminum chloride (AlCl3) exposure on rat ovaries.

MAIN METHODS

Eighty female Wistar (5weeks old) rats, weighed 110-120g, were randomly divided into four treatment groups: control group (CG), low-dose group (LG, 64mg/kg BW AlCl3), mid-dose group (MG, 128mg/kg BW AlCl3) and high-dose group (HG, 256mg/kg BW AlCl3). The AlCl3 was administered in drinking water for 120days. The ovarian ultrastructure was observed. The activities of acid phosphatase (ACP), alkaline phosphatase (ALP), succinate dehydrogenase (SDH), Na(+)-K(+)-ATPase, Mg(2+)-ATPase and Ca(2+)-ATPase, the contents of Fe, Cu and Zn, and the protein expression of follicle-stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) in the ovary were determined.

KEY FINDINGS

The results showed that the structure of the ovary was disrupted, the activities of ALP, ACP, SDH, Na(+)-K(+)-ATPase, Mg(2+)-ATPase and Ca(2+)-ATPase, the contents of Zn, Fe and the protein expression of FSHR and LHR were lowered, and the content of Cu was increased in AlCl3-treated rats than those in control.

SIGNIFICANCE

The results indicate that sub-chronic AlCl3 exposure caused the damage of the ovarian structure, the disturbed metabolism of Fe, Zn and Cu and the decreased activities of Na(+)-K(+)-ATPase, Mg(2+)-ATPase and Ca(2+)-ATPase in the ovary, which could result in suppressed energy supply in the ovary. A combination of suppression of energy supply and reduction of expression of FSHR and LHR could inhibit ovulation and corpus luteum development, leading to infertility in female rats.

Effects of treatment for anestrus in water buffaloes with PGF2α and GnRH in comparison with vitamin-mineral supplement, and some factors influencing treatment effects

The effect of treatment for anestrus in buffaloes with a PGF2α or GnRH injection and vitamin-mineral (Vit-M) supplementation for 1 to 2 months and some factors influencing the treatment effect were studied. In anestrus buffaloes with CL, an injection of PGF2α tended to show higher estrus detection and pregnancy rates within 17 days after treatment than Vit-M supplementation (P<0.10). In those with inactive ovaries, effect of GnRH and Vit-M did not differ. Body condition score of the animals before treatment affected pregnancy rate within 17 days after treatment (P<0.05). Pregnancy rate within 4 months after treatment was adversely influenced by low serum concentrations of calcium (P<0.01) and gastrointestinal parasitic infection before treatment (P<0.05).

Retinoic acid influences the embryoid body formation in mouse embryonic stem cells by induction of caspase and p38 MAPK/JNK-mediated apoptosis

Although all-trans retinoic acid (RA), the oxidative metabolite of vitamin A, is essential for normal development, high levels are teratogenic in many species. RA results in immediate effects on the preimplantation embryo and on blastocyst development in vitro and in vivo. To further elucidate the cellular mechanisms of early postimplantation embryo development induced by RA, we present an embryonic cell line, B5, as a candidate system for the investigation of these processes. We used undifferentiated ES cells as the model, which is from the undifferentiated status to differentiated status [embryoid body (EB) formation] mimicking postimplantation embryo development (egg-cylinder stage of embryo formation) to clarify the cellular mechanism of action of RA in the implanted blastocysts and cell apoptosis following the series of exposures to differing RA concentrations. Using an in vitro model, we identified the impact of RA on undifferentiated embryonic stem (ES) cells, including inhibition of cell proliferation and induction of cell apoptosis. JNK, P-38 and caspase activation were shown in the nature of RA-triggered apoptotic signaling in ES cells. The carry-on influences of RA on the ES cell were shown in the formation of EB from the pretreated ES cells. RA resulted in apparent impact on undifferentiated ES cells in vitro, with increased numbers of apoptotic cells initially and inhibited cell proliferation, which led to decreased size of EB. The process of EB formation (mimicking the early postimplantation embryo development) is regulated by RA-induced apoptosis through the activation of caspase and P38 MAPK/JNK pathway.

Utilização de minerais iônicos ou complexos orgânicos de minerais no pré-parto de vacas Holandesas

Os efeitos do uso de minerais complexados durante o pré-parto sobre a ocorrência de retenção de placenta foram avaliados em 135 vacas Holandesas de dois ou mais partos: grupo mineral iônico (69 animais) e grupo mineral complexado (66 animais). Em 55 desses animais foram também avaliadas as concentrações séricas da imunoglobulina G (IgG), Zn, Cu e a qualidade do colostro. O experimento foi realizado em delineamento inteiramente ao acaso, em arranjo em parcelas subdivididas. As concentrações séricas de IgG e dos microminerais foram avaliadas por análise de variância, sendo utilizados, respectivamente, os testes de Duncan e Fisher. A taxa de erro α admitida foi de 7%. Não foram observadas diferenças entre os grupos para ocorrência de retenção de placenta, qualidade do colostro, concentrações séricas de Zn e IgG (P>0,07), sendo observada diferença para a concentração de Cu (P<0,07). As concentrações de IgG foram diferentes nas semanas pré-parto avaliadas (P<0,07).

Oocyte aspiration and in vitro embryo production in Jersey cows with selenium-supplemented diet

The effects of selenium (Se) in Jersey cows' diet on the aspiration of oocytes and production of embryos in vitro were studied. Groups with five Jersey cows received 3.2mg or 9.6mg Se daily, provided in the feed concentrate. Six follicular aspirations were carried out every 15 days, using only the last 5. The oocytes were classified, and standard procedures were carried out for maturation, fertilization and cultivation. The total number of oocytes (35.11±2.65 vs 23.10±2.16) and degree 1 oocytes (11.61±2.65 vs 4.75±0.97) were higher in the group that received 9.6mg Se and the quantity of naked oocytes (3.23±0.87 vs 6.22±1.18) was lower in this group. The aspirated oocytes from the cows treated with 9.6mg Se/day resulted in higher (P<0.05) embryo production 21.98±2.37 vs 13.12±1.59). No difference was observed in serum Se concentration between the two groups. It is recommended that the daily diet be supplemented with 100g mineral salt containing 9.6mg Se, since this rate rendered a larger production of oocytes, higher quantity of degree 1 oocytes and greater production of embryos in the process of in vitro fertilization.

Effects of mineral supplements on ovulation and maturation of dog oocytes

The aim of this study was to assess the effects of trace mineral supplements near the time of ovulation on the number of ovulated oocytes, in vivo oocyte maturation and pregnancy for dog cloning. Sixteen oocyte donor dogs were used in each control and mineral supplement group, and 136 and 166 corpora lutea were counted from each group. No significant difference was observed between oocyte recovery rates in the control (91.2 ± 2.7%) and mineral (89.9 ± 2.7) groups. Proportions of mature (86.2 ± 7.2 and 88.4 ± 6.8%) and aged (13.8 ± 7.2 and 11.6 ± 6.8%) oocytes were not different in the control and mineral groups, respectively. Oocytes with fair (91.5 ± 3.6 and 93.6 ± 2.1%) and poor (8.5 ± 3.6 and 6.4 ± 2.1%) quality also showed no difference between the control and mineral groups. The concentrations of manganese and ferrous iron were higher and lower on the day of ovulation, respectively, in both groups, but trace element concentrations in peripheral blood were not affected by mineral treatment. Oocytes were used to make cloned embryos; after embryo transfer, four and two pups were delivered from the control and mineral group, respectively, but there was no difference in the delivery rate (4.6 and 2.7%). In conclusion, intravenous mineral supplements administered once close to the LH surge in oocyte donor dogs and recipients had no effect on the number of ovulated oocytes, in vivo oocyte maturation or pregnancy in dog cloning in this study.

Socioeconomic factors and vitamin a status of pregnant women in Calabar urban, southeastern Nigeria

Vitamin A deficiency (VAD) is prevalent in developing countries. Socioeconomic status is increasingly being associated with nutritional status of individuals. Efforts to control or eliminate VAD must focus on socioeconomic factors and how to tackle them in the midst of other well recognized strategies. This research sought to determine the socioeconomic factors that may affect the serum retinol levels of pregnant women in Calabar, Nigeria. A total of 101 pregnant women in Calabar were studied for the effect of socioeconomic factors on the maternal vitamin A status using a structured household questionnaire and biochemical analytical techniques. The study revealed that a majority (82.2%) of the women studied were in their normal reproductive years (20-45 years), 63.4% had previous childbirth experience, 89.1% had formal education, 85% were employed, 85% lived in medium to large families (4 persons and above) while 62.3% were in the middle or high income class (over N50,000 per month). Among the women, only 35.6% had adequate vitamin A status while the rest had deficient (15.8%), low (32.7%) or very high (15.8%) levels. The results of the analysis of the influence of socioeconomic characteristics of the women on serum retinol status showed a positive relationship between serum retinol level and education (P < 0.05; F = 2.84) and between serum retinol level and parity (P < 0.05; F = 2.05). Serum retinol concentration was not affected by age, occupation, household size and other household characteristics used in the study. Increased maternal education and appropriate child spacing may be the key strategies for the elimination and control of vitamin A deficiency in developing countries.

Vitamin D - roles in women's reproductive health?

In the past few years a growing interest in vitamin D can be observed in the lay and biomedical literature due to findings demonstrating a low vitamin D status in the population. In addition to its importance for the regulation of calcium and phosphorus homeostasis recent epidemiologic studies have observed relationships between low vitamin D levels and multiple disease states. This secosteroid hormone also regulates the expression of a large number of genes in reproductive tissues implicating a role for vitamin D in female reproduction. In this report we summarize the recent evidence that vitamin D status influences female reproductive and pregnancy outcomes. Human and animal data suggest that low vitamin D status is associated with impaired fertility, endometriosis and polycystic ovary syndrome. Evidence from observational studies shows higher rates of preeclampsia, preterm birth, bacterial vaginosis and gestational diabetes in women with low vitamin D levels. However, confirmation of experimental observations establishing an association of vitamin D deficiency with adverse reproductive outcomes by high quality observational and large-scale randomized clinical trials is still lacking. The determination of optimal 25(OH)D3 levels in the reproductive period and the amount of vitamin D supplementation required to achieve those levels for the numerous actions of vitamin D throughout a woman's life would have important public health implications.