Ovarian dynamics, hormone profiles, and characterization of ovarian and uterine blood flow in cycling Sahiwal cows

The objectives were to investigate the ovarian dynamics and hormonal profiles during the oestrus cycle, and to characterize the ovarian and uterine blood flow (OBF versus UBF) indices on the extent of vascular perfusion towards the dominant follicle (DF) or corpus luteum (CL) during the peri-ovulatory follicular wave in Sahiwal cows. In experiment 1, cyclic cows (n = 21) were selected at their spontaneous oestrus (day 0) and subjected to B-mode ultrasonography throughout the oestrus cycle. In experiment 2, cyclic cows (n = 9) were randomly selected at day 0, and categorized according to the intra-ovarian patterns as ovaries with DF (n = 3), CL (n = 3) or both (DF+CL; n = 3) to characterize the OBF and UBF indices using Doppler ultrasonography. The length of the oestrus cycle (days), number of follicular waves (n) and size (mm) of DF and CL were 20.1 ± 0.9, 2.1 ± 0.2, 14.7 ± 0.7 and 15.9 ± 2.5, respectively. The concentrations (ng/mL) of plasma progesterone increased linearly, and a peak was attained at day 12.2 ± 1.0. However, it reduced linearly with the onset of luteolysis at day 16.4 ± 0.3 of the oestrus cycle. The plasma progesterone (P4) concentrations and the diameter of CL correlated throughout the oestrus cycle. The mean OBF and UBF indices did not differ between intraovarian patterns. Taken together, this information on reproductive physiological parameters could be used to develop synchronization protocols to improve reproductive management in Sahiwal cows.

Comparative analysis of the hormone production and gene expression profiles in ovine uterus tissue during oestrus cycle synchronized using medroxyprogesterone acetate plus eCG and prostaglandin analogue

The combination of medroxyprogesterone acetate (MPA) and gonadotropin chorionic (eCG) has been widely used to synchronize oestrus cycle in sheep, but their effects on the gene expression in uterine tissue are yet to be elucidated. To evaluate the effect of MPA + eCG or prostaglandin analogue (PA) treatments on the rate of oestrus cycle synchronization, as well as further hormone production and gene expression profiles in uterine tissue, 14 Santa Inês ewes were randomly selected. The MPA + eCG group (n=7) received intravaginal insertion of MPA-impregnated sponges for 14 days and was administered 350 IU eCG on the day of sponge withdrawal. The PA group (n=7) was administered two doses of 100 μg of PA separated by 12 days. The ewes were assessed for the rate of oestrus cycle synchronization and the serum concentrations of progesterone (P4) and estradiol (E2). Additionally, the expression of estrogen receptor (ERα), progesterone receptor (P4R), and immunolocalization of interferon receptor (IFNAR1) in the uterine tissue samples collected 15th day post-mating were examined. The rate of oestrus cycle synchronization was 100% (n=7/7) and 57.14% (n=4/7) in the MPA + eCG and PA groups, respectively. Moreover, the MPA + eCG group exhibited higher serum concentration of P4 than the PA group (p < 0.05). However, the E2 serum concentration did not differ between the two groups (p > 0.05). The relative expression of P4R and ERα mRNA analyzed using real-time PCR and immunodetection of IFNAR1 were similar between the two groups tested (p > 0.05). Conclusively, MPA + eCG treatment improved the rate of oestrus cycle synchronization and endogenous P4 production; however, it did not affect the expression of sex steroid receptors and IFNAR1 in uterine ovine tissue.

Experiments confirm a dispersive phenotype associated with a natural gene drive system

Meiotic drivers are genetic entities that increase their own probability of being transmitted to offspring, usually to the detriment of the rest of the organism, thus ‘selfishly’ increasing their fitness. In many meiotic drive systems, driver-carrying males are less successful in sperm competition, which occurs when females mate with multiple males in one oestrus cycle (polyandry). How do drivers respond to this selection? An observational study found that house mice carrying the t haplotype, a meiotic driver, are more likely to disperse from dense populations. This could help the t avoid detrimental sperm competition, because density is associated with the frequency of polyandry. However, no controlled experiments have been conducted to test these findings. Here, we confirm that carriers of the t haplotype are more dispersive, but we do not find this to depend on the local density. t -carriers with above-average body weight were particularly more likely to disperse than wild-type mice. t -carrying mice were also more explorative but not more active than wild-type mice. These results add experimental support to the previous observational finding that the t haplotype affects the dispersal phenotype in house mice, which supports the hypothesis that dispersal reduces the fitness costs of the t .

Penurunan Durasi Berbaring Harian Sapi Berahi, sebagai Peluang untuk Dijadikan Teknologi Otomatisasi Peringatan Dini Sapi Berahi

ABSTRAK. Saat ini sudah tersedia berbagai produk teknologi monitoring kesehatan ternak berdasarkan analisis tingkah laku ternak. Namun belum ada teknologi monitoring berdasarkan tingkah laku yang cocok untuk pemeliharaan intensif seperti di Indonesia. Penelitian ini bertujuan untuk mendapatkan dasar teknologi monitoring sapi berahi berdasarkan perubahan total durasi berbaring harian antara sapi berahi dengan non berahi. Sebanyak 18 ekor sapi betina Peranakan Ongole (PO) sehat reproduksi ditempatkan pada kandang individu yang terpantau kamera selama 24 jam. Pengambilan data foto posisi berbaring atau berdiri sapi dilakukan tiap 2 menit. Dilakukan penjumlahan durasi total berdiri dan berbaring harian selama satu siklus berahi. Penentuan kondisi berahi menggunakan metode visual dan menggunakan heat detector “Brunstmessgerat”. Uji T test berpasangan dilakukan untuk membandingkan rata-rata berbaring harian sapi non berahi dengan durasi harian sapi berahi. Hasil penelitian menunjukkan bahwa lama siklus berahi adalah sebesar 20,3 ± 1,5 hari yang mengindikasikan sapi sehat secara reproduksi dan mendapatkan ketercukupan nutrisi pakan. Data total durasi berbaring harian yang didapatkan dari hasil tangkapan foto kamera menunjukkan sebaran data yang terdistribusi normal dan terdapat perbedaan yang nyata antara total durasi berbaring harian sapi berahi 49,83% dengan rata-rata total durasi berbaring harian sapi non berahi 53,60%. Hasil ini membuka peluang untuk dikembangkan menjadi teknologi monitoring sapi berahi berdasarkan perbedaan tingkah laku berbaring sapi. (Decreasing of the total daily lying behavior on oestrus cow, as an opportunity to become an automatic warning system for oestrus cows) ABSTRACT. Today, various livestock health monitoring technology products based on the analysis of livestock behavior are available. However, there is no behavior-based monitoring technology suitable for intensive maintenance such as in Indonesia. This study aims is to obtain the basic monitoring technology for heat cows based on changes of the total daily lying behavior duration between oestrus and non oestrus cows. A total of 18 healthy PO cows were placed in individual pan which were monitored by the camera in 24 hours a day. Collecting photo data from lying or standing position of the cow was done every 2 minutes. The total duration of daily standing and lying behavior for one oestrus cycle was done. The determination of the heat condition used a visual method and a heat detector manufactured by Brunstmessgerat. Paired T-test was conducted to compare the average daily lying behavior of oestrus and non oestrus cows. The results showed that the oestrus cycle length was 20,3 ± 1,5 days, which indicated that the cows were reproductively healthy and had adequate feed nutrition. The total daily lying behavior duration data obtained from the camera photo captures showed that the distribution of data is normally distributed and there is a significant difference between the total daily lying behavior duration of oestrus 49,83% and non oestrus 53,60%. This result opens the opportunity to be developed into a monitoring technology for oestrus cows based on differences in the lying behavior.

Characteristics of Reproductive Tracts of Repeat Breeders in Cattle

The study observed the characteristics and assessed abnormalities in reproductive tracts of repeat breeders in cattle. Fourty (40) herds were sampled during the study and fifty seven (57) repeat breeders were identified. The animals had normal reproductive tracts with good body condition scores (BCS) ranging from 2.5- 4.5. There was no correlation between the ages and the body condition scores of the repeat breeders (r = -0.4576. Higher number of repeat breeders were found within the ages of 3 -6. Variation within the ages of the repeat breeders were not significantly associated. Physical and behavioral characteristics observed were: crystal clear eyes; appearing more like a castrated bull; physically strong; active; vibrant; alert; stubborn; wild; temperamental; aggressive and difficult to handle; very sensitive to their environment and have a quick idea of the presence of a stranger which they show by having their ears in erect disposition signaling a sign of insecurity and danger. They always appear as superior animals in the herds; and could even be used as draught or pack animals with a very good output. They could yield better meat compared to none repeat breeders in the herds. Thus, most repeat breeders are not sterile, have normal oestrus cycle every 18-24 days but rather suffer from lowered fertility resulting to huge economic waste due to more services; reduced milk yield; wide calving interval and culling rate. It was concluded that repeat breeders suffer from lowered fertility which results into reduced milk yield, wide calving interval and culling rate.

Reproductive performance and superovulatory endangered Cameroonian Namshi breed (Bos taurus)

This study was undertaken to determine the reproductive performance of the endangered Bos-taurus Namshi breed of Cameroon. Ovarian response to superovulatory treatment was also evaluated. The following observations were recorded. The average calf mortality rate was 25.71% while the average birth weight was 12.22±0.82kg. The percentage of animals in oestrus during the wet and dry season was respectively 60% and 33.4%. The oestrus cycle length and the oestrus duration were respectively 20.80±1.20d and 7.00±0.80h: corresponding dry season figures for those parameters were 19.00±0.94d and 6.00±0.7h respectively. In the dry season the manifestation of oestrus was 80º during the day and 20º at night while in the wet season it was 55.55% and 44.5% respectively. Postpartum oestrus was at 18 months. The ovarian response to superovulatory treatment was about 6.40±2.50 ovulations per cow. Results indicate that the scarcity of Bos-taurus Namshi breed in Camerron could be attributed to high calf mortality rate, low calving rate and long postpartum periods. Embryo transfer could be a way to rapidly multiply this breed.

SEASONAL EFFECTS ON OESTRUS PATTERNS AND PROGESTERONE PROFILES OF YANKASA EWES OF DIFFERENT AGE-GROUPS IN THE SUB-HUMID TROPICS

Oestrus patterns and serum progesterone profiles of 10 adult and 10 yearling Yankasa ewes were investigated in the late hot-dry and late-wet seasons in the subhumid tropical climate of Zaria, Nigeria. The proportions of ewes which came on heat once, twice or thrice within the experimental periods in the late hot-dry and late-wet seasons were 25, 15 and 0%, and 5, 10 and 85% respectively, while mean oestrous cycle length was significantly longer (P<0.001) in the hot-dry season than in the late-wet season (30.9 vs 18.4 days) due to the higher incidence of anoestrus in the former. However, the mean duration of oestrus was not affected by season. Mean serum progesterone levels were significantly (P<0.05) higher in the late-wet season than in the late hot-dry season (1.57 vs 0.52 ng/ml). However, there was a highly significant (P<0.001) interaction between season and age group in mean serum progesterone levels due to a relatively greater depression in progesterone levels in yearling ewes during the hot-dry season compared with adult ewes. The observed disruptions in the oestrus cycle and serum progesterone levels of the ewes in the hot-dry season confirm the adverse effect of heat stress on the reproductive behaviour of ewes.

Moody Mares—Is Ovariectomy a Solution?

Unwanted behaviour in mares is a commonly presenting problem to the veterinarian. This behaviour may range from the mare being uncooperative or aggressive when handled on the ground, kicking, bucking or rearing when ridden or being aggressive towards other horses. This purpose of the study was to evaluate whether bilateral ovariectomy in mares with unwanted behaviour improved the mare’s behaviour and/or rideability from the owner’s perspective. The mares were grouped and compared statistically based on their histological classification as having either “normal” or neoplastic ovaries. This study is a retrospective case series report of twenty-eight ovariectomized mares. A semi-quantitative value (1–10) pre- and post-ovariectomy for A) behaviour on ground/in stable and B) rideability was given, based on the owner’s observations. The horses were grouped based on their histopathologic diagnosis as “Normal ovaries” or “Neoplasia”. Following ovariectomy, rideability improved, with a score of ≥5 in 80% (8/10) of mares with normal ovaries and in 57% (8/14) of mares with ovarian neoplasm. A behavioural improvement of ≥5 was observed in 40% (4/10) of mares with normal ovaries, and in 43% (6/14) of mares with ovarian neoplasm. A significant difference was observed between the semi-quantitative value pre- and post-ovariectomy in both groups. No difference was observed in change in behaviour and rideability score between the group with normal ovaries and neoplastic ovaries. Mares with unwanted behaviour not obviously related to the oestrus cycle and to painful conditions may benefit from ovariectomy to alter their behaviour and rideability.

Efficiency of timed pregnancies in C57BL/6 and BALB/c mice by mating one male with up to four females

For a wide range of biomedical approaches, an accurate estimate of the age of embryos or pups is important. Overnight mating is the method that is mostly used to establish timed pregnancies. The oestrus cycle in mice repeats every four to five days. So, not all females will get pregnant because they are not in oestrus. Therefore, the aim of this study was to analyse whether polygamous mating could increase the rate of timed pregnancies per breeding cage and female. We compared overnight timed mating regimes with up to four females per male, using C57BL/6 and BALB/c mice as well as F1 hybrids of these two strains. The number of vaginal plugs, number of females that gave birth and weaned litter (including size and weaning weight) were recorded. Our results showed that the plug and pregnancy rate decreased, but the productivity per breeding cage increased for polygamous mating regimes. The proportion of females with vaginal plugs and females that gave birth was significantly higher in monogamous mating. The proportion of plugged females that gave birth, as well as litter size and weaning weight, were not influenced by the mating regime. After analysing 513 breeding cages with a total of 1090 females, we found that polygamous mating with up to three females per male can increase the number of timed pregnancies. However, in the mating regime with more than three females, the rate of timed pregnancy as well as number of pups per female declined.