جستجوی مقالات مرتبط با کلیدواژه "آبستنی" در نشریات گروه "دامپزشکی"

Growing infertility and a reduction in pregnancy rates are two of the most challenging issues facing modern dairy cows. Our objectives were to determine pregnancy rates, plasma progesterone concentrations, and corpus luteum (CL) numbers in high-producing dairy cows during two distinct periods (cool and warm seasons). This evaluation followed the administration of: 1) human chorionic gonadotropin (hCG) on day 5 after AI, 2) a combined treatment with hCG on day 5 and flunixin meglumine between days 14 and 16 after AI, and 3) flunixin meglumine alone between days 14 and 16 after AI.

Cows were subjected to pre-synch programming in two experiments (cool period, n = 396) and warm period, n = 181), respectively. Environmental data in the warm period indicated that cows experienced high heat stress during the trial in the warm period (THI = 85-92). Cows in both experiments were randomly divided into four groups: Group 1 received hCG, and Group 2 was given hCG on day 5 and FM on days 14–16, Group 3 was treated with FM on days 14–16, and the untreated group was the control group. Ovarian structures and serum progesterone levels were determined on days 5 and 12 after AI, respectively. Ultrasonography was used to evaluate the pregnant status of cows on days 28-30.

There was a significant difference in p4 concentrations 12 days after IA between groups in the cool period, in both the hCG and hCG+FM groups (p = 0.001). But the discrepancy in p4 was not observed between groups in the warm period (p = 0.7). The increase in CL for cows treated with hCG compared with control cows was greater during the cool (1.7 vs. 1.1) period compared to the warm (1.1 vs. 1.3) period (p = 0.001). In the warm season, no significant difference in pregnancy rate on day 30 between the four groups was obtained.

Our results indicated that administration of flunixin meglumine did not improve pregnancy rates in dairy cows during either the warm or cool seasons. Conversely, treatment with hCG on day 5 after artificial insemination induced accessory corpora lutea, increased plasma progesterone concentration, and improved pregnancy rates in dairy cows during the cool period only. None of these effects were observed during the warm period.

The aim of this research was to examine the serum vitamin D status in Gray Shirazi ewes during different reproductive stages, including mating, pregnancy, and early lactation. A total of 60 healthy ewes were sampled at three stages. The first stage was during mating, the second stage was in the late pregnancy, and the third stage was after delivery. The blood samples were analyzed for 25-hydroxy vitamin D levels. At delivery, multiple births, weight of lambs, and stillbirth rates were recorded. The results revealed that the mean serum vitamin D levels were significantly higher in the third stage of sampling (beginning of lactation) compared to the first stage (mating) and the second stage (pregnancy) (P=0.014 and P=0.017). However, there was no significant difference in vitamin D levels among the non-pregnant (the ewes that did not become pregnant after mating), singleton, and twin groups at any of the sampling stages. Vitamin D levels were highest at the beginning of lactation in gray shirazi ewes. Additionally, serum vitamin D was slightly decreased in pregnant ewes as the number of lambing increased. In total, the findings suggest that maintaining sufficient vitamin D levels may play a role in reproductive health in sheep, as there appears to be a correlation between vitamin D levels and fertility.

This study was aimed to investigate the status of energy balance during mating, pregnancy and after lambing and its relationship with reproductive outcomes in Gray Shirazi sheep. Thirty healthy Gray Shirazi ewes that were kept in industrial conditions were randomly selected. During lambing, the ewes were examined for the rate of multiplication as well as abortions and the weight of lambs at birth. Blood sampling was performed during mating, on the last two to four weeks of pregnancy, and on one to two weeks after delivery. Serum levels of insulin-like growth factor-1 (IGF-1), insulin, non-esterified fatty acids (NEFA) and beta-hydroxybutyric acid (BHBA), and progesterone were assessed. There was a significant rise in IGF-1 level in late pregnancy compared to that in early lactation. In addition, the concentration of BHBA was significantly increased during pregnancy and postpartum compared to the mating time. Maximum BHBA and NEFA concentrations at the end of pregnancy and postpartum were in twin and singleton pregnancies, respectively. In addition, the highest BHBA concentrations were accompanied by the lowest BCS of ewes. Moreover, there was a significant direct correlation between lamb weight and NEFA, BHBA, and progesterone. In conclusion, serum indicators of energy balance, particularly insulin and BHBA, are largely influenced by reproductive stages, especially pregnancy and the number of lambs in Gray Shirazi ewes. Accurate identification of these changes is essential in diagnosing abnormal conditions and metabolic and nutritional disorders in this breed.

Ascertainment of fetal sex is important in the equine industry for economic reasons. As a result, various methods have been developed for the sex determination of a fetus in a horse; however, the current techniques have some limitations. Recently, evaluation of maternal testosterone concentration has been suggested as an easy and inexpensive method for diagnosing fetal sex, but the findings are discrepant in different species.

The aim of the present study was to measure the concentration of circulating testosterone in mares carrying male and female fetuses in order to assess the diagnostic value of maternal testosterone concentration for sex determination of equine fetus.

Blood samples were collected from mares (n=20) at months three, six, and nine of pregnancy. The samples were centrifuged and stored at -20°C until hormonal analysis of testosterone concentration using an ELIZA kit. The gender of foals was determined at birth based on observation of external genitalia.

Neither testosterone concentration in the third, sixth and ninth months of pregnancy nor the cumulative concentration of testosterone differ between mares with male and female fetuses (P>0.05). However, testosterone concentration changed during pregnancy in all mares regardless of the gender of their fetus, and it was higher at month six than at months three and nine (P<0.0001).

In conclusion, the present study showed that maternal testosterone concentration could not be used for the sex determination of a fetus in a horse. Yet the current study revealed testosterone concentration dy-namics over various gestation stages in mares.

The objective of this study was to obtain the first time of pregnancy diagnosis and the images of fetal development in different times of pregnancy period using ultrasonography.

Two-dimensional ultrasound from day 25 to 120 of pregnancy was performed twice a week from days 25 to 65 and once a week from days 65 to 120 of pregnancy on ten Kurdish sheep. The ultrasonographic images were obtained Sonosite Titan (USA) 2D ultrasound machine.

On the 25th day, the pregnancy was diagnosed. On 39th day, clear pictures of pregnancy like amniotic membrane, and umbilicus were seen. On 75th day of gestation, internal organs of fetus like heart, kidney, liver, urinary bladder, and stomach were seen in the images. The scrotum in the male fetus was identified on the 89th day of gestation. Between the 110th and 120th days of gestation, complete details of internal organs were seen in ultrasonographic images.

The transrectal probe to detect pregnancy is better than transabdominal probe. The accuracy of 2D ultrasound was 100% for detecting pregnancy. The shape of fetus changes in the images from days 25 to 42 in each ultrasound scan, and on the 42nd day of pregnancy, the fetus is fully identified.

Periostin (POSTN) is an extracellular matrix (ECM) protein that plays an important role in the metastatic process and cancer cell migration. As implantation is a similar mechanism to metastasis, it has been hypothesized that POSTN may also play a role in the implantation process.

The aim of the present study was to compare POSTN and progesterone levels during the early pregnancy stage in Damascus goats.

Forty goats were synchronized using progesterone based sponges and were mated upon estrus signs display. While ten goats were kept as control (CON) and were not allowed to mate. Blood samples were taken through jugular venepuncture from CON and synchronized goats on day 13, 15, 17, 19, and 21 of breeding. Progesterone and POSTN levels were determined by enzyme-linked immunosorbent assay (ELISA). Later the pregnancy diagnosis was confirmed by transabdominal ultrasonography on day 50 after mating.

Progesterone level was influenced by status of pregnancy and day of observation with an interaction between the status of pregnancy and day of observation in goats. Whereas POSTN level was only affected by the day of observation.

POSTN level did not vary with progesterone level during phase of embryonic implantation in goats; however, standardization and application of different procedures for POSTN assay in a large group of animals might be useful as an early pregnancy biomarker in goats.

Research has demonstrated that certain nutrients can reverse infertility.

The present study, “Impact of Omega-3 fatty acids preconception intake on some fertility parameters of female rats and foetuses quality” was conducted to further investigate this subject.

Subjects were thirty-four female and twelve male adult Albino rats, weighing 172-181 g. Initially, 12 male rats were assigned to treatment groups 1, 2, 3, and 4, and 24 females were assigned to treatment groups 5, 6, 7, and 8. The treatment protocol was administered orally as follow: groups 1 and 5 (controls), 0.3 ml distilled water (as placebo); groups 2 and 6, 250 mg/kg Omega-3 fatty acids (O3FA); groups 3 and 7, 25 mg/kg cyclophosphamide (CPP, negative control); and groups 4 and 8, 25 mg/kg CPP + 250 mg/kg of O3FA for 28 days. Thereafter, they were cohabitated (1:2 male to female ratio) into mating groups 1 to 7 until mating was confirmed. Ten pregnant rats (5 of which were administered 500 mg/kg O3FA on days 15 and 16 of gestation) were used for abortifacient effect experiment.

Number of implantation sites (IM), implantation index (IMI), percentage of pregnant females (PPF), life foetal number, foetal weight, foetal crown-rump length (FCRL), corpora luteal number (CLN) and fertility index (FI) in O3FA-treated female rats and their foetuses significantly increased (P<0.05) compared with negative control. No noticeable abortifacient effect occurred.

Preconception intake of O3FA may have impacted female fertility positively.