mojtaba kafi

So far, changes in the vaginal microbial population during the estrous cycle have been evaluated in several livestock species such as sheep. However, changes in the rumen microbial population have not been investigated during the estrous period in sheep. In a study, the results showed that the differences in the rumen microbial population in two reproductive seasons were due to the differences caused by the reaction to day length, and nutrition did not have much effect on it. It is possible that during the reproductive and non-reproductive seasons, the animal has a different microbial population in the digestive tract. The available evidence from clinical research in animals shows that microbes in the digestive system can alter brain activity and behavior through hormonal and neural pathways. Therefore, this study mainly aims to investigate changes in the rumen microbial population during the reproductive season in the estrous period in ewes with estrus and those without estrus for any reason or are so-called anestrus. The changes in the rumen microbial population during the breeding season in the estrous period were measured for the animals showing the occurrence of estrus and those not showing this trait or were anestrous.

This research was done at the same time as the non-breeding season (late spring-beginning of July). The ewes were of Grey Shirazi breed (2-3 years old). To investigate changes in the rumen fluid microbial population in the estrus cycle in estrus and non-estrus animals, two groups of 10 animals were formed from estrus and anestrus animals with the use of teaser rams, and rumen fluid samples were collected for microbial culture and other investigations in both groups once per four days (5 times) during 17 days (like estrus cycle days). The colonies were cultured and separated using general culture media with different growth factors for anaerobic bacteria colonies, such as plate count agar, MRS agar (de Man-Rogosa - Sharpe), and starch agar. The colonies were subtracted by subtractive cultures or different diagnostic tests to identify colonies. Data were analyzed using SAS software version 1/9. Means were compared with the least square procedure and adjusted for Tukey's test.

The population difference between the two groups at 5 different times showed that the population of lactic acid bacteria (LAB) on the day of estrus showed a higher value and a significant difference with other times than the anestrus group. Lipolytic bacteria were higher on the day of estrus than on all days in both groups, with a significant difference. The comparison of different groups showed that the estrous group from times 1 to 5 in the breeding season had the highest number compared to the other groups at different times of the study (p < 0.05). Anestrous groups also had the lowest number at all times (p < 0.05). The comparison of the two estrus and anestrus groups showed that heat and ninth days had higher values than the other times. In comparing the average number of lipolytic colonies in the estrus group, the highest and the lowest numbers belonged to the 1st and the 4th times, respectively, which were significantly different from the other times (p < 0.05). The population of proteolytic bacteria had the highest number of bacteria at time 1 and showed the next values at times 2, 5, 3, and 4, respectively, compared to the estrus group at time 5 (p < 0.05). Time 5 was not significantly different from times 2 and 3 (p < 0.05). In this season, the estrus group was the highest and the lowest at times 1 and 4, respectively (p < 0.05). Times 3-5 were no different significantly (p < 0.05). In the anestrus group, times 3 and 1 had the highest number vs. the lowest numbers in times 2 and 5  (p < 0.05). Based on the comparison of the average population resulting from the counting of total bacterial colonies in the examination of different groups, the estrous group had the highest number of the average microbial population in all 5 times (p < 0.05). The lowest number belonged to two anestrus groups (p < 0.05). The population difference between the two groups at 5 different times showed that the population of LAB had a higher value only on the day of estrus, with a significant difference compared to the anestrous group. The population of lipolytic bacteria in two groups of estrus and anestrus in the 5 studied times showed that the estrus group had a higher and significant value than the anestrus group in the 4th time, i.e. the day of estrus and days 5, 6, and 17. The results showed that the total bacterial population was higher in the estrus group at all times, with a significant difference. Furthermore, anaerobic bacteria increased significantly in certain days of estrus (days 1-9) compared to the anestrous group. The population difference between the two groups at 5 different times indicated that the population of LAB had a higher value only on the day of estrus, with a significant difference compared to the anestrous group. The population of lipolytic bacteria in the two estrus and anestrus groups in the 5 studied times revealed that the estrus group had a higher and significant value than the anestrus group in 4 times, i.e. days of estrus, 5, 6, and 17. The total bacterial population in the estrous group was higher and significant at all times.

In general, the colony population of amylolytic and lipolytic bacteria and the total colonies of anaerobic bacteria are significantly different on days of the estrus cycle, which may affect reproduction. Accordingly, it is better to provide more understandable results of rumen microbial effects on estrus in ewes by increasing analyses such as hormonal changes and molecular investigations, along with microbial culture in estrus crops.

The surge in fast food consumption in recent years is considered a threat to human health. This change in the life habit has raised serious concerns among health policy-makers and medical nutrition researchers. Environmental stress, multitasking, low physical activity, and low academic achievement have been shown to influence the predilection for consuming fast food.1 We have now faced with one similarly threatening phenomenon among university students and academics, which can be termed “fast research”.

There is no sufficient information on the impact of bovine ampullary oviductal epithelial cells (BAOECs) on in vitro oocyte maturation competence and gene expression.

This study aimed to examine the oocyte developmental competence following co-culturing with a monolayer of fresh and frozen-thawed ampullary cells.

Bovine cumulus-oocyte complexes (COCs) were distributed into three groups: control group; where in COCs were cultured in cell-free media for 24 hr and FML and FTML groups in which the COCs were cultured in maturation media for 18 hr and then transferred into a media containing fresh and frozen-thawed BAOECs monolayer, respectively (BAOECs were extracted from the oviducts of slaughtered cattle and were then cultured freshly or frozen-thawed) for a further 6 hr. After 24 hr, the expanded COCs were evaluated for nuclear maturation, fertilization rate, and gene expression (GDF9, StAR, CASP3, and FSHr).

Nuclear maturation rate in the FTML group was significantly higher than the control group (p = 0.02). The fertilization rate of FTML group was significantly higher than the control and FML groups (p = 0.05 and p = 0.03, respectively). In terms of gene expression, GDF9 were upregulated in the presence of the BAOECs during the last 6 hr of the in vitro maturation (p < 0.001). Furthermore, the expression of the StAR gene in the FTML group was higher than the other groups (p = 0.02).

Ampullary cells co-culturing (especially frozen-thawed cells) for in vitro maturation of bovine oocytes yields encourages the results and demonstrates the beneficial effect of co-culture on gene expression and developmental competence.

Nowadays, assisted reproduction has become an essential part of the management of horse reproduction in different parts of the world. In vitro production of equine embryos requires established techniques including oocyte collection, in vitro oocyte maturation and intracytoplasmic sperm injection. No report is available on in vitro oocyte maturation of horse oocytes in Iran. Ovaries were immediately collected from newly dead mares of different ages, and transported to the laboratory. The visible follicles were opened using a scalpel blade and the granulosa layers of the follicle wall were scraped from the follicle. Then, the ovaries were cut in 5 mm sections to collect more oocytes from follicles within the ovarian stroma. The oocytes were cultured in TCM-199 medium, supplemented with 10% fetal calf serum and hormones, in a CO2 incubator at 38.5 0C for 30 h. In addition, using a home assembly devised ovum pick-up (OPU) system, five attempts were made to collect oocytes from preovulatory follicles in four mares. After 30 h in culture, the denuded oocytes were fixed and stained with aceto-orcein to determine the nuclear maturation of the oocytes. Out of 29 cultured oocytes from dead mares, 15 (51.7%) oocytes reached the metaphase II. Further, of five OPU operations on live mares, one compact COC suitable for culture and one degenerate COC were collected. The results of this report describe the feasibility of ovum pick-up and oocyte collection from either live mares or immediately after death of the animal and further successful in vitro maturation of the equine oocytes.

Nicotinic acid (niacin) is a broad-spectrum lipid-modifying agent that has potent antioxidant properties and reduces the production of lipid peroxidation.

The purpose of the present study was to investigate the maturation, embryo development and cryo-tolerance merit, and levels of malondialdehyde (MDA), total oxidant status, and total antioxidant capacity following the supplementation of bovine oocytes maturation medium with different concentrations of niacin.

Immature cumulus-oocyte complexes were cultured in tissue culture medium-199 maturation media supplemented with 0, 100, 200, and 400 µM niacin under a standard in vitro culture condition. After 24 hr of culture, the nuclear maturation rate was assessed. Then, two groups of immature cumulus-oocyte complexes were cultured in TCM-199 either with or without 400 µM niacin and evaluated for embryo development. Also, matured cumulus-oocyte complexes in both groups were frozen using a standard vitrification procedure. After vitrification, oocytes were warmed in two steps and evaluated for embryo development. In addition, the level of total antioxidant capacity, total oxidant status, and MDA were measured.

The results indicated that although the treatment with 400 µM niacin increased in vitro nuclear maturation (87.6±5.3), it did not improved the embryo development to the blastocyst stage. Higher cleavage and blastocyst rates were observed in vitrified oocytes that were cultured with supplemented 400 µM niacin compared to the control group (without niacin) (53.6±2.7 and 10.6±1.6 vs. 46.2±4.1 and 6.3±2.4, respectively). Also, the addition of 400 μM niacin to the maturation media could decrease MDA levels after maturation.

Niacin could improve the quality of in vitro embryo production (IVP) embryos and tolerance of bovine oocytes to vitrification.

The aim of this study was to determine the incidence and quantify risk factors associated with repeat breeder (RB) syndrome in Isfahan Holstein dairy cows. Calving and insemination data of parities 1 to 7 on 91727 Holstein dairy cows from 62 herds collected during 1993 to 2013 were used. Cows failed to conceive after three or more regularly spaced services in the absence of detectable abnormalities regarded as RB. A multivariate logistic regression model was used to quantify risk factor associated with repeat breeding. Least squares mean number of services per conception were 2.15 ± 0.15 and 2.54 ± 0.15 for normal and RB cows, and uncorrected values were 2.73 and 3.28 for normal and RB cows, respectively. Herd, milk yield, season of calving and season of first insemination, dystocia, stillbirth, abortion and days from calving to first service were the major factors affecting RB syndrome. Average incidence of repeat breeding was 43.7% (27.8-55.2%). Dystocia and stillbirth increased the odds of being RB by 39% and 11%, respectively (P< 0.01). Risk of being RB in high producing cows increased by 79% compared to cows with low milk yield (P< 0.01). Odds of being RB increased by 28% in cows that was RB in previous parity. Fat yield and length of dry period had no significant effect on being RB. Considering at least 75 days distance between calving and first service, insemination in cool seasons, decreasing dystocia and improving reproduction management of high producing cows, could reduce RB syndrome.

During the last few decades, there has been an increase in the development of mathematical models, as both research tools and management tools that can integrate our current knowledge of reproductive events and then would be helpful in predicting the reproductive efficiency of farm animals. This paper presents a conceptualized mathematical modeling of hormonal and metabolites interactions over non-estrous and negative energy balance phase in dairy cow. Anestrus occurs annually and after each calving. The anestrus period in high milk-producing cows due to the negative balance of energy produced by high milk production in the first few days after parturition is a constant challenge in the modern world of dairy cow worldwide. For this reason, many scientific efforts have been made to explore the biological aspects of this phase. Due to the complexity of the existing relationships between effective parameters, descriptive-analytical biological analyses have not succeeded in elucidating this biological system. In this research, it was attempted to look at the elaborating factors playing in this phase, at same time, it was tired to pinpoint and explore this phase from biological system perspective.
Material and In the present study, first diverse information on the various aspects of the factors affecting on the postpartum negative balance of energy and reproduction performance of dairy cows were initially collected. Then, this information was converted to their sound mathematical equations. Efforts have been made to simplify the long and unprocessed equations from well-known factors including liver glucose, blood glucose, pancreatic insulin and blood insulin, IGF-1 liver and blood, and hypothalamic GnRH affecting on this biological phase to be simplified using ordinary differential equations. In other part of this study, By using the data published in the scientific articles and expanding them by using Curve Expert software, the computer simulation process was performed by MATLAB software (Version 9.1) and the predictive models were developed for some system parameters. The results showed that the system of ordinary differential equations was able to predict good blood glucose (AARD = 0.388) and insulin (AARD% = 0.638), but they were not able to provide accurate predictions for pancreatic insulin and blood IGF-1.
The present model was a starting point to reach a comprehensive model which should be completed gradually. In this model, it was tried to use empirical data from reliable sources in simulation model, a matter that was more or less successful in this research.

Adiponectin is one of the most important adipocytokines that regulate male and female fertility via AdipoR1 and AdipoR2 receptors. Recently expression of adiponectin system and its negative regulatory role on hypothalamus-pituitary axis have been confirmed. No information is available about the expression pattern of adiponectin and its receptors in hypothalamus-pituitary axis in domestic animals. Here for the first time, we studied hypothalamus-pituitary adiponectin system gene expression in different stages of bovine estrous cycle. Anterior pituitary and hypothalamus were collected from Holstein cow at the local abattoir. The estrous cycle was classified to four phases (proestrous, metstrous, early luteal and late luteal) based on macroscopic examination of ovaries and uteri. Gene expression analysis of adiponectin and its receptors was done using quantitative real time PCR (qPCR Probe MasteKit) and according to the comparative 2-ΔΔCt method. E2 and P4 levels were measured using ELISA method. Our results demonstrated that adiponectin and its two receptors were expressed in pituitary and hypothalamus of cyclic cow. Maximal expression of adiponectin was observed in early luteal phase, while it was expressed at minimal level during the proestrous stage. We observed no significant changes in the expression of AdipoR1 in both tissues at different stages of estrous cycle. The highest expression of AdipoRII in both tissues was detected during the proestrous stage, while it expressed at minimal level during the late luteal phase. E2 and P4 had respectively negative and positive correlations with adiponectin expression levels in hypothalamus and pituitary. Based on our results that demonstrated adiponectin was minimally expressed at proestrous stage and other data about the negative action of adiponectin on LH secretion from pituitary, we concluded that adiponectin may has role in the hormonal function of this axis during the estrous cycle.

The following study was carried out to determine the ultrastructural features of the oocyte of the ovulatory-sized follicles in relation to concentrations of steroids and IGF-I in the follicular fluid and serum in the dromedary camel. Camel follicles with a clear and healthy appearance were categorized into three classes: follicles 10 to 13.9, 14-17.9 and 18-30 mm diameter. The Follicular Fluid (FF) and serum samples were assayed for estradiol-17β, progesterone and IGF-I. Recovered Cumulus-Oocyte Complexes (COCs) were prepared for transmission electron microscopy. The mean (±SD) FF concentrations of progesterone and IGF-I was significantly (p<0.05) higher in follicles 18 to 30 mm diameter compared to other groups of follicles. There was no difference in the mean (±SD) serum estradiol-17β, progesterone and IGF-I concentrations between camels with different ovulatory-sized follicles (p>0.05). Oocytes from follicles 18 to 30 mm diameter (group 3) showed more advanced signs of maturation including the disappearance of the nuclear envelope, increased number of microvilli in erect position, the increase in number and size of vesicles and more even distribution of the mitochondria throughout the ooplasm. The final stages of oocyte maturation in dromedary camel is associated with increasing progesterone and IGF-I concentrations and constant high estradiol concentration in the follicular fluid which are paralleled with well-defined ultrastructural changes in oocytes.

Bovine venereal campylobacteriosis, caused by Campylobacter fetus subsp. venerealis (Cfv), is regarded as one of the major threats to the cattle industry around the world. Abortion and infertility are two important reproductive problems in cows infected with C. fetus subsp. venerealis. Reports on the presence of Cfv are scarce in the cattle, in Iran. Therefore, the present study was designed to examine the presence of Cfv in the reproductive tract of dairy cattle either slaughtered in Shiraz abattoir or dairy herds with a history of infertility and abortion, and further to identify and differentiate this micro-organism in dairy cattle in Fars, south of Iran. A total of 95 smegma samples from the preputial cavity and the fornix of the cervical opening were collected using scraping method from bulls (n = 34) and cows (n = 61) in addition to eight samples of commercially bull frozen semen. Smegma samples were then cultured for isolation of Cfv and then the extracted DNA was examined for the presence of Cfv using an optimized multiplex PCR assay. None of the frozen semen samples examined were positive for Cfv. However, out of 95 smegma samples, thirteen animals (12.6%) were found positive for Cfv consisting of 3 males and 10 females. In conclusion, the results of the current study clearly confirmed the presence of Cfv using PCR in the slaughtered cattle and dairy farms with a history of poor fertility and abortion in Fars, Iran.