Difference In Conception Rate Research Articles

Decline in the Conception Rate of Wild Japanese Monkeys after the Fukushima Daiichi Nuclear Power Plant Accident

We examined the conception rate of wild Japanese monkeys (Macaca fuscata) in Fukushima City that were exposed to radiation as a result of the Fukushima Daiichi Nuclear Power Plant accident in March 2011. The conception rate in the year of delivery from 2009 to 2022 was estimated by dissecting individuals that were euthanized by the government for population control as a countermeasure against crop damage. To evaluate the effects of exposure, the cumulative exposure dose for each individual was calculated using the concentration of radiocesium deposited in the soil at the capture site and the concentration of radiocesium in muscle estimated from the aggregated transfer factor. There were no significant differences in conception rates across all age classes over time. In terms of conception rates by age class, there was a significant decrease post-exposure compared with pre-exposure in the age class ≥ 8 years, but no significant differences in the age class 5–7 years. The non-ovulation rate did not significantly differ between the pre- and post-exposure periods for any age class. Body fat index, which can affect fertility, was compared between the pre- and post-exposure periods, and no significant differences were found in either age class. In contrast, the median total cumulative exposure (cumulative internal exposure + cumulative external exposure) was significantly higher in the age class ≥ 8 years compared with the age class 5–7 years. These results suggest that the total cumulative exposure dose may be one of the reasons for the lower conception rate in the post-exposure period among the age class ≥ 8 years.

Genetic and Managerial Factors Affecting the Conception Rate of Cows in Rajshahi City Corporation Area of Bangladesh

Given the significant economic importance of getting cows pregnant, we investigated the factors affecting the conception rate of cows in Rajshahi City in this study. As we know, when the sperm fertilizes the egg, this is the moment we call conception. The number of dams that actually give birth compared to the number of dams that have been served or exposed to the sire is traditionally understood to be the conception rate. There have been many management and environmental factors, such as nutrition, metabolic disorders, reproductive health, heat detection, insemination practices, and climate, which can result in significant differences in conception rates. In terms of the effect of herd size on cow’s conception, we observed that herd with >30 cows had the highest (71.12%) conception rate (P<0.001), while the overall conception rate was 60.28%. Private farms showed higher conception (66.68%) than NGO-led ones (22%). Farmers having higher (>3 years) experience managed better conception rate (62.34%) in their farms. Cows under good housing management showed better conception (65.65%) than poorly or on-averagely maintained ones. Cows that were given good quality feed showed better conception (66.82%) compared to those provided with medium to poor quality feed; likewise, cows supplied with good quality fodder performed better regarding CR (63.68%). Cows that were under regular deworming resulted better (63.90%) conception rate compared to irregularly (55%) or no-dewormed (22.22%) groups. Regarding the effects of breed on CR we noticed that Friesian crossed showed better conception (75.13%) than local (50%) and Sahiwal crossed (40%). About the effect of age, 4-6 years old cows showed a better conception rate (68.88%), and in terms of parity 3rd one revealed highest conception rate (84.26%). We noticed frozen semen performed better (62.43%) than liquid ones (57.24%) and the govt. supplied semen resulted in better CR (65%). Heat detection through mounting resulted in a better conception rate (68.08%) than bellowing (67.14%) and vaginal discharge (52.57%), and service around 12-18 hours of Heat showed the highest conception rate (76.32%). In terms of the effect of methods of pregnancy detection on conception rate we noticed that by observing the clinical signs, we can better confirm conception (70.69%) compared with rectal palpation (38.14%). Under various limitations, we carried out our experiment; our findings are striking; however, further studies are needed to go more in-depth into it

145 Specific Gravity as an Assessment of Embryonic Viability to Improve Implantation Rates for in Vitro Produced and in Vivo Derived Bovine Embryos

Abstract The objective of this study was to evaluate the ability of a specific gravity chamber (SGC) to identify embryos most likely to result in successful implantation following embryo transfer. In this study, 19 in vitro produced (IVP) and 15 in vivo derived (IVD) Grade bovine embryos were allowed to descend through media in an SGC. Descent time through a 1-cm timing region was recorded, and embryos were retrieved from the chamber and transferred into recipient females or cryopreserved and transferred at a later date. To determine if chamber evaluation had an effect on pregnancy status, 27 IVP and 12 IVD embryos that were not evaluated with the SGC were also transferred alongside project embryos. Pregnancy was determined via transrectal ultrasound palpation and recorded. There was no significant difference in conception rates between embryos evaluated with the SGC and those not, indicating that chamber analysis had no negative impact on viability of both IVP (P = 0.54) and IVD (P = 0.93) embryos. Twenty-two of the 34 total project embryos resulted in successful implantation and pregnancy, with 13 pregnancies (68.4%) by IVP and 9 (60%) by IVD. There was no difference in average descent time of pregnant and non-pregnant embryos for IVP (P = 0.54) or IVD embryos (P = 0.24). When divided into groups according to descent time, 32% of all observations for IVP embryos occurred between 30 to 50 seconds with a 66.7% conception rate, and 42% occurred between 70 to 90 seconds with a 75% conception rate (P = 0.85). For IVD, 60% of all observations occurred between 90 to10 seconds, with a conception rate of 66.7% (P = 0.35). Though not significant, the numeric trends highlighted in these data lend support to previous research utilizing specific gravity. Further research is needed to thoroughly evaluate the potential of this technology as a method of noninvasive assessment of embryo viability.

Feedlot rearing versus pasture grazing enhances plasma leptin and insulin-like growth factor-1 concentrations but does not anticipate puberty in dairy buffalo (Bubalus bubalis) heifers

Plasma Leptin (LEP) and Insulin-like Growth Factor-1 (IGF-1), related to growth and puberty onset, were assayed in growing buffalo heifers from 8 up to 21 months of age, reared in feedlot (FR, n = 13; initial body weight 132 ± 11 Kg) or grazing at pasture (PG, n = 13; 137 ± 12 Kg). The mean age at puberty was not different between the two groups (599.5 and 610.5 days, in FR and PG, respectively). At puberty, FR heifers showed higher BCS, and higher average daily weight gain (DWG) than PG ones (0.87 vs. 0.62 Kg/day), and were heavier (462 vs. 375 Kg). A negative correlation between DWG and age at puberty was significant for the PG group. Plasma Inhibin-A increased in both groups one month before puberty. Plasma LEP and IGF-1 sharply increased 2 months before puberty (about 18 months old) in FR heifers only, which showed higher concentrations of both hormones than PG heifers. Plasma LEP levels correlated positively with body weight and IGF-1. Despite hormone levels being affected by rearing systems, and being lower in heifers grazing at pasture, these latter experienced adequate growth and reproductive maturation. In fact, grazing heifers reached puberty at the same age as the feedlot reared ones, with shorter puberty–conception interval (51.3 vs. 67.2 days, for PG and FR groups, respectively) and no difference in conception rates (83.3 and 84.6%, for PG and FR groups respectively). The higher BW and DWG of FR heifers were due to body fat deposition, which did not anticipate the puberty onset. Highlights Metabolic hormones Leptin and IGF-1, linked to puberty attainment, are good indicators of the animal energetic state. Buffalo heifers reared in intensive system vs. the ones at pasture had higher hormone levels and growth, but reproductive performance was not better. Post-weaned heifers can be reared at pasture during growth and breeding, without compromising reproductive performance.

Risk Factors for the Efficiency of Artificial Insemination in Dairy Cows and Economic Impact of Failure of First Service Insemination in and around Haramaya Town, Oromia Region, Eastern Ethiopia.

A cross-sectional study was conducted from November 2019 to May 2020 in and around Haramaya Town to study the risk factors of artificial insemination (AI) in dairy cattle and evaluate the economic impact of failure of first service AI. A questionnaire survey and field follow-up were employed for collecting data from cattle owners and artificial insemination technicians (AITs) who were selected purposively. Out of the 221 inseminated cows and heifers, the overall conception rate was 60.2% (n = 133). The conception rate was statistically different between breed (P=0.019) and insemination time (P=0.049). From a total of 133 conceived cows and heifers, the conception rate was 68 (53.54%) in local breeds and 65 (69.15%) in cross breeds. Parity, age of cows, inseminator experience, and body condition of cows did not create a significant difference in conception rate (P > 0.05). Failure to conceive at their first AI results in an extra cost of 440 ETB per day until conception. Therefore, to increase the conception rate, dairy cows should be inseminated early when they show signs of estrous; the owners of dairy cows should be trained on how to detect estrous signs in dairy cows and AI technicians should also take training in order to improve their skills.

Temperature, climate change, and human conception rates: evidence from Hungary

In this paper, we examine the relationship between temperature and human conception rates and project the impacts of climate change by the mid-twenty-first century. Using complete administrative data on 6.8 million pregnancies between 1980 and 2015 in Hungary, we show that exposure to hot temperatures reduces the conception rate in the first few weeks following exposure, but a partial rebound is observed after that. We project that with absent adaptation, climate change will increase seasonal differences in conception rates and annual conception rates will decline. A change in the number of induced abortions and spontaneous fetal losses drives the decline in conception rates. The number of live births is unaffected. However, some newborns will experience a shift in the timing of conception that leads to changes in in utero temperature exposure and therefore might have further consequences.

PSIII-9 Differences in Conception Rate across Breeding Protocols in Dairy Cattle

Abstract Fertility performance success on dairy farms starts with estrus detection, especially for artificial insemination programs. Detection of estrus has become more difficult over the years due to a decrease in estrus expression in high-producing dairy cows, with up to 60% of ovulations accompanied by no standing mount. In order to alleviate the pressure of estrus detection, management technologies have been developed, including automated detectors of standing heat, activity monitors, automated in-line systems measuring milk progesterone, and hormonal synchronization protocols (FTAI). To gauge the effectiveness of such technologies, records from 647,940 cows across 1,166 herds over the past ten years (total of 3,466,593 breeding records) from herd management software were analyzed. Across all herds, there were 5,804 breeding protocols, of which 2,046 were unique. Due to the wide range of breeding protocols, records were classified as HORMONES, FTAI, HEAT DETECTION and OTHERS. Breeding protocols were classified as HORMONES if they included any hormone treatment. FTAI was a stricter subset of HORMONES, which included only clear FTAI protocols. Protocols were classified as HEAT DETECTION if they were a clear heat detection protocol, with all remaining protocols classified as OTHERS. These classifications resulted in 3,258 protocols classified as HORMONES, of which 2,002 were FTAI, while a further 1,840 were classified as HEAT DETECTION. The remaining 706 codes were classified as OTHER and removed from this study. These classifications provided an initial overview of breeding methods conception rates, with results indicating significant differences (P < 0.05) between all protocol groups, as outlined in Table 1. Further analysis will be completed to indicate conception rates from the most commonly used breeding protocols across each of the protocol groups within the 1,192 herds. This work will help provide a better understanding of the expected conception rate of various management technologies on commercial farms.

Investigating conception rate for beef service sires bred to dairy cows and heifers

The widespread use of sexed semen on US dairy cows and heifers has led to an excess of replacement heifers' calves, and the sale prices for those calves are much lower than in the past. Females not selected to produce the next generation of replacement heifers are increasingly being bred to beef bulls to produce crossbred calves for beef production. The purpose of this study was to investigate the use of beef service sires bred to dairy cows and heifers and to provide a tool for dairy producers to evaluate beef service sires' conception. Sire conception rate (SCR) is a phenotypic evaluation of service sire fertility that is routinely calculated for US dairy bulls. A total of 268,174 breedings were available, which included 36 recognized beef breeds and 7 dairy breeds. Most of the beef-on-dairy inseminations (95.4%) were to Angus (AN) bulls. Because of the limited number of records among other breeds, we restricted our final evaluations to AN service sires bred to Holstein (HO) cows. Service-sire inbreeding and expected inbreeding of resulting embryo were set to zero because pedigree data for AN bulls were unavailable. There were 233,379 breedings from 1,344 AN service sire to 163,919 HO cows. A mean (SD) conception rate of 33.8% (47.3%) was observed compared with 34.3% (47.5%) for breedings with HO sires mated to HO cows. Publishable AN bulls were required to have ≥100 total matings, ≥10 matings in the most recent 12 mo, and breedings in at least 5 herds. Mean SCR reliability was 64.5% for 116 publishable bulls, with a maximum reliability of 99% based on 25,217 breedings. Average SCR was near zero (on AN base) with a range of -5.1 to 4.4. Breedings to HO heifers were also examined, which included 19,437 breedings (443 AN service sire and 15,971 HO heifers). A mean (SD) conception rate of 53.0% (49.9%) was observed, compared with 55.3% (49.7%) for breedings with a HO sire mated to a HO heifer. Beef sires were used more frequently in cows known to be problem breeders, which explains some of the difference in conception rate. Mean service number was 1.92 and 2.87 for HO heifers and 2.13 and 3.04 for HO cows mated to HO and AN sires, respectively. Mating dairy cows and heifers to beef bulls may be profitable if calf prices are higher, fertility is improved, or if practices such as sexed semen, genomic testing, and improved cow productive life allow herd owners to produce both higher quality dairy replacement and increased income from market calves.

Increased Likelihood of Pregnancy Using an App-Connected Ovulation Test System: A Randomized Controlled Trial.

Background: Women trying to conceive are increasingly using fertility-tracking software applications to time intercourse. This study evaluated the difference in conception rates between women trying to conceive using an application-connected ovulation test system, which measures urinary luteinizing hormone and an estrogen metabolite, versus those trying without using ovulation testing.Materials and Methods: This home-based study involved 844 volunteers aged 18–40 years seeking to conceive. Volunteers randomized to the test arm were required to use the test system for the duration of the study while those randomized to the control arm were instructed not to use ovulation testing. Pregnancy rate differences across one and two cycles between the two groups were examined.Results: Volunteers in the test (n = 382) and control arms (n = 403) had similar baseline demographics. The proportion of women pregnant after one cycle was significantly greater in the test arm (25.4%) compared with the control arm (14.7%; p < 0.001). After two cycles, there continued to be a greater proportion of women pregnant in the test arm compared with the control arm (36.2% vs. 28.6%; p = 0.026). In the test arm, volunteers had intercourse less frequently per cycle compared with those not using ovulation testing (9 [range: 1–60] vs. 10 [range: 1–50]; p = 0.027), but were more likely to target intercourse to a particular part of their cycle compared with those not using ovulation testing (88.5% vs. 57.8%; p < 0.001).Conclusion: Using the test system to time intercourse within the fertile window increases the likelihood of conceiving within two menstrual cycles.

Fertility parameters in German dairy herds: Associations with milk yield and herd size

Fertility in dairy cows has decreased over the last fifty years while milk production per cow has increased. Furthermore, dairy herds become larger resulting in fewer employees per cow, which might also influence reproductive performance. To elucidate the situation in Germany, selected parameters (conception rate, service rate, pregnancy rate, days to first insemination and days open) were studied using data on 148 herds. For statistical analysis the herds were categorized concerning milk yield: (1) &amp;lt; 30 kg, (2) 30‒35 kg, and (3) &amp;gt; 35 kg/cow/day as well as concerning herd size: (1) &amp;lt; 200, (2) 200‒400, (3) 400‒1000 and (4) &amp;gt; 1000 milking cows. There was no difference in conception rate among herds. That means on dairy farms of larger size or with high milk yield the chance of an inseminated cow to become pregnant is the same as in small herds or in herds with low milk yield. Small herds (&amp;lt; 200 cows) had lower pregnancy rates than larger herds (200–400 cows). The pregnancy rate in herds with different milk yield was not statistically different. Though there was a trend that dairy farms with higher milk yield (&amp;gt; 30 kg) had higher pregnancy rates. The statistical differences and trends of pregnancy rates are due to higher service rate in larger herds as well as in herds with high milk yield. Therefore, service rate is the key factor for high reproductive performance on dairy farms. Poor fertility is not associated with high milk yield on herd basis or large herd size but may represent inappropriate farm management.

Post artificial insemination conception rate of a Brahman bull in selected areas of Bangladesh

Background: To mitigate the increasing protein demand in Bangladesh, recently the government has started a program to inspire the farmers for rearing Brahman as a beef breed. But, it is necessary to assess the performance of frozen semen of Brahman bull and the other factors that affect the rate of conception after Artificial Insemination (AI) before widespread rearing in Bangladesh. Methods: Data on AI performance, different factors and rate of conception were collected from 150 inseminated cows and heifers of Sadar upazila, Mymensingh. The cows were inseminated by trained technician of Research Animal Farm of Department of Surgery and Obstetrics, BAU, Mymensingh. Results: The overall conception rate was 55.3%. The conception rate in Holstein Friesian cross (68.9%) and Sahiwal cross (66.7%) cows were relatively higher than that of Local (46%) cows. Upon increasing age the service required for conception was irregular. The conception rate with respect to different parities ranged from 47.0% to 58.7%. Cows received insemination at parity 1-2 showed highest conception rate (60.0%) and cows received insemination at parity 3-7 showed lowest conception rate (47.0%). There was no significant difference between them on conception rate. The conception rate was observed higher (69.2%) in the cows which were inseminated in spring than cows were inseminated in summer (57.3%), winter (53.3%) and rainy (38.5%). The pregnancy rate in cows having BCS 2.5-3 was higher (60.7%) than that of 2.0 and 3.5-4.0. However, the difference in conception rate did not vary significantly among different BCS of cows (p&gt;0.05). The present study indicated that the pregnancy rate in cows was higher (76.9%) that yield 6-10 L of milk than those of 0, 1-2 and 3-5 L counterpart. However, the variation in conception rate with different milk yield was significant (p&lt;0.05). The pregnancy rate in cows that inseminated between 19-24 hours was higher (66.0%) than that of ≤12 and 13-18 hours. The variation in conception rate with different interval between estrus to AI was significant (P&lt;0.05). Conclusion: Further studies using more population of cows and semen donors are needed to confirm this result as low number of cows and only one semen donor were used in this study.

Synchronization of Estrus by ‘Buck Effect’ and PGF2α Treatment in Surti Does

This investigation was aimed to study the influence of buck and PGF2α treatment on estrus synchronization in Surti does. Apparently healthy non-pregnant Surti does (n=18) were identified from the flock by Ultrasonography. They were evenly divided into 3 groups, 6 does in each group. The does of Treatment T1 group were teased with a sexually-active-apronized buck; the does of Treatment T2 group were treated with PGF2α, i.e., Inj. Lutalyse® @ 7.5 mg/doe IM twice, i.e. on day 0th and 11th, while the does of Control group T3 were kept without any treatment. The behavioural estrus was successfully synchronized by double injection of PGF2α at 11 days apart, as well as by buck effect in T2 and T1 groups, respectively. The induction of estrus was observed cent per cent in all the groups within one month. The mean time intervals between start of treatment and onset of estrus differed significantly between T1 (5.83±2.20 d) and T3 (14.67±2.76 d) groups. However, the mean duration of estrus was 29.83±0.91, 27.50±1.23 and 28.67±1.28 hrs and the mean number of services per conception was found 1.33±0.33, 1.50±0.50 and 1.33±0.33 for T1, T2 and T3 groups of Surti does, respectively, none differ significantly (p&gt;0.05) between the groups. There was no significant difference in conception rates at first service amongst the groups (83.33%). The 17 does among 18 does (94.44 %) from all the three groups conceived within three services, irrespective of treatment groups. It was found that the buck effect appeared to be as effective as conventional PGF2α treatment in Surti does for synchronization of estrus

Conception rate following intra-cervical artificial insemination using frozen semen at field level in indigenous sheep of Bangladesh

This study was undertaken to study the AI conception rate using frozen semen at field level. Five farms in Mymensingh, Bangladesh were selected for AI Trial in field ewes. Four rams were selected for semen collection, evaluation, and frozen semen production and further to study conception rate followed by intra-cervical AI in both natural and synchronized ewes. Conception rate were confirmed by non-returned rate and ultrasound scanning at 30-40 days of post insemination. The volume, colour, mass activity, sperm motility, viability, concentration, HOST +ve (%) and normal spermatozoa percentages were 0.8±0.3 ml, 3.9±0.3, 4.4±0.6, 81.3±5.0%, 90.0±4.0%, 3519.0±545.6x106/ml, 87.4±3.3% and 85.6±1.8%, respectively. The sperm concentration of ram R#6 was significantly higher (P&lt;0.05) (4120.5±93.5x106/ml) compared with other rams. The mean motility and viability of pre-dilution, 120 minutes of addition of Part-A, 240 minutes of addition of Part-B and post-thaw were (83.8±4.8%, 81.3±2.5%, 80.0±4.1% and 41.3±9.5%) and (93.3±1.0%, 90.0±1.4%, 88.8±1.0% and 58.3±8.7%), respectively. There were no significant difference (P˃0.05) between pre-dilution and post-dilution sperm motility and viability percentage however, post-thaw sperm motility and viability significantly (P&lt;0.05) decreased compare with the motility and viability of pre-dilution and post-dilution values. Motility and viability percentages of frozen semen did not decrease significantly (P&gt; 0.05) with the increase of preservation time. The mean motility and viability at 24 hrs, day 7, day 15 and day 30 were 41.3±9.5%, 41.5±8.5%, 41.8±9.9% and 40.5±10.2%; and 59.0±10.1%, 58.5±7.7%, 59.0±8.8% and 57.8±8.3%, respectively. The conception rates in natural and synchronized estrous were 26.7% and 25%, respectively. There was no significant difference in conception rates between the natural and synchronized oestrous in field level. However, the present non-return rate and conception rate indicate the suitability of produced frozen semen application in the field level.Asian J. Med. Biol. Res. March 2018, 4(1): 55-62

Biostimulation and reproductive performance of artificially inseminated rabbit does (Oryctolagus cuniculus)

Biostimulation is a non-hormonal and practical technique that has not yet been widely utilised when applied immediately before insemination to improve reproductive efficiency in livestock species. This study was conducted to determine the influence of short-term male biostimulation on behavioural and reproductive performance of inseminated rabbit does. A total of 142 female New Zealand White rabbits were randomly assigned to 3 groups. Females were either exposed to male odour (Odour group) or an adult aproned male (Male group), while the remaining does that were neither exposed to the male odour nor the adult male are considered the control group. All females were inseminated after the 2 h exposure session. Conception rates were determined by abdominal palpation 12 d after insemination. The results showed that conception rate of the male odour group (79.59%) was greater than that of male presence group (76.09%) and that of the control group (68.09%). Moreover, biostimulated does showed significant behavioural activities during the 2 h exposure session compared to the control group. Although no significant differences were recognised, litter size at birth and at weaning was slightly increased in biostimulated compared to control females. Nor were there any significant difference in serum oestradiol concentrations between treated groups. Conclusively, short-term 2 h biostimulation of rabbit does resulted in the appearance of various behavioural responses followed by differences in conception rates between groups after routine artificial insemination.

Effect of progesterone and oxytocin on conception rate in repeat breeding Cattle

A total of 50 cross bred repeat breeder cattle were selected and grouped into 4 treatment and one control group which belonging to organized farms around, K. V. K. Gandhar, Jehanabad. Hydroxyprogesterone caproate (500 mg) was administered I.M. on day 4 post A. I. in group I, In group II, 500mg progesterone was administered I M on day 4 and again on day 10. Evatocin (40 I.U.) was administered I.M. 5 minutes before A.I. to animals belonging to group III. The same drug was used through Intra vulvo-submucosal route (15 I.U.) to animals of group IV. Group V animals received no treatment and served as control. Pregnancy diagnosis was done by rectal palpation D 45-60 after artificial insemination. In group I, the conception rate was found to be 60% as against 20 % in the control (Non-significant), Gr II, the conception rate improved from 20% in control animals to 70% in treated animals (Significant) and Gr III, the C.R. 60% than control(20%) where as Gr IV, C.R. 40% . The difference in conception rate of treatment and control group animals was non-significant.

Effect of GnRH or Estradiol Benzoate on Reproductive Traits during a Heatsynch Protocol in Dairy Cows

Background: Milk production of cows is closely correlated with its reproductive efficiency. One of the several factors influencing the dairy efficiency is the decline in fertility of the cows/heifers. Use of hormonal protocol are often used to improve the fertility of the recipients. Several programs are available to inseminate dairy cows, with variation in the use of different types of hormones, time of use and range of duration period, as well as the time of AI. The objective of this study was to evaluate the efficiency of follicular wave emergence induction of estradiol benzoate in comparison to GnRH in a Heatsynch protocol and its influence on reproductive parameters.Materials, Methods &amp; Results: In this study were used primiparous and multiparous Holstein cows (n = 325). Animals were divided randomly into two different treatments according with the hormone used to induce follicular wave emergence (D0). The GnRH group (n = 167), was given 25 mg, while in the EB group (n = 158) was used 2 mg. At same day, were inserted, a controlled internal drug-releasing containing 1.9 g of progesterone CIDR®. On day 7, CIDR was removed and cows were given 25 mg luteinizing hormone followed by an injection of 1 mg Inducer Ovulation at day 8. Cows were then observed for signs of estrus for at least two hours (twice daily at 7 am and 6 pm) for three days following CIDR® removal. Cows detected in estrus were inseminated 12 h later the estrus detection. Pregnancy status was determined by ultrasonography at 30 ± 5 d and 60 ± 5 d after AI. A single technician was responsible for the estrus detection and inseminations. A single technician was responsible for the estrus detection and inseminations. Ultrassonographic examinations with ultrasound, transrectal linear probe of 5 MHz, were performed for the diagnosis of pregnancy at 30 and 60 days after artificial insemination. Binomially distributed data, such as, estrous response, conception rate, pregnancy rate and pregnancy losses, were analyzed by Chi-square test. Pregnancy rates at 30-35 days and 60-65 days as well as pregnancy losses were considered in the model for the effect of parity (primiparous vs. multiparous) and the group of estrus behavior during the Heatsynch protocol. Conception rate was similar between GnRH (36.1%, 57/158) and EB (37.7%, 63/167) treatments. Cows showing estrus signs after CIDR removed were 71.9% in GnRH and 62% in EB group (P = 0.05). Embryonic losses were different (P = 0.03) according to groups of cows showing estrus signals or not.Discussion: Our results demonstrate that conception rates are not affected by using either EB or GnRH at the beginning of the Heatsynch protocol. Therefore, the EB can be an alternative choice to GnRH at Heatsynch beginning. Similar results were found by autor in dairy cows, once it was also observed that there is no difference in conception rate in two TAI protocols using either GnRH or EB. In Heatsynch protocols the increase in estrus detection are a key factor to increase fertility in lactating dairy cows. It can be explained once animals in regular estrous cycle have a palpable corpus luteum and circulating progesterone concentration higher than 1 ng/mL which leads than to enhance pregnancy ratios. The use of BE at the time of CIDR insertion in TAI protocols for dairy cattle proved to be an alternative to GnRH considering conception rates. Therefore, the use of BE at the time of CIDR insertion in a Heatsynch protocol in dairy cattle proved to be an alternative to GnRH which can be an important tool to increase the TAI utilization by farmers. Furthermore, in Heatsynch protocol cows showing estrus have pregnancy rates improved and lower pregnancy losses.

8 RESPONSE OF COMMUNAL COWS TO OESTRUS SYNCHRONIZATION AND TIMED ARTIFICIAL INSEMINATION

Reproductive technologies such as oestrus synchronization and AI have been tested in controlled environments in the commercial farms in South Africa but not in an uncontrolled communal setup. The aims of the study were to evaluate the response of communal cows to oestrus synchronization and timed AI. The effects of age and body condition score (BCS) on oestrus response and conception rate were also studied. A total of 96 cows were selected from the communal villages. Cows with the BCS of 2.5 to 4.5 (on a scale of 1–5) and age between 3 and 10 years were used. Cows were grouped into 2 BCS groups (&lt;3 and = 3) and 2 age groups (&lt;6 and = 6). All groups were subjected to a 9-day Ovsynch + CIDR (CIDR®; Pfizer Laboratories, New York, NY, USA) protocol. A CIDR® was inserted into the vagina on Day 0 (random days of the cycle), and 2 mg of oestradiol benzoate (Ciderol®; Pfizer Laboratories) was administered. On Day 8, the CIDR® was removed, and the cows were administered with 500 μg of cloprostenol (PGF; Estrumate®, Schering-Plough Animal Health). In addition, on Day 9, cows were given 1 mg of oestradiol benzoate, and a heat mount detector (Karma®; Four Lakes) was placed on the tail head of the cows to detect oestrus response (standing heat). All the synchronized cows were then inseminated at 36 and 42 h with frozen-thawed Nguni bull semen following oestradiol benzoate injection. Pregnancy diagnosis was performed 90 days following timed AI using ultrasound scanner and transrectal palpation. Data were analysed using ANOVA. An overall 73% oestrus response and 45% conception rate were achieved in this study. There was no significant difference in oestrus response in cows with a BCS &lt;3 (67%) and = 3 (83%) or age &lt;6 (77%) and = 6 (72%). There was no significant difference in conception rate between those &lt;6 (41%) and = 6 (47%) years of age. However, cows with a BCS of = 3 had greater (P &lt; 0.05) conception rate (55%) compared with those with a BCS &lt;3 (35%). In conclusion, communal cows responded to an oestrus synchronization program involving timed AI. The BCS and age did not alter the oestrus response, but conception rate was higher in communal cows with BCS of = 3.

Effects of progesterone inclusion in a gonadotropin–prostaglandin–gonadotropin programme on follicular dynamics and ovulation synchronisation of pasture-based dairy cows with anoestrous

The aim of this study was to evaluate how the addition of a progesterone device to a gonadotropin–prostaglandin–gonadotropin (GPG) programme in dairy cows with postpartum anovulatory anoestrus affected ovarian follicular dynamics and the synchronisation of ovulation. Twenty-two dairy cows were randomly assigned to either GPG (Day 0: 100μg GnRH, Day 7: 500μg PGF2α, Day 9: 100μg GnRH, Day 0–7: Day 10) or GPG with a progesterone device from Day 0 to 7 (GPG+P4). Ovarian follicular dynamics and ovulation synchronisation were studied using transrectal ultrasonography. Compared to the GPG+P4, GPG alone resulted in a relatively larger mean dominant follicle size and a higher mean peripheral oestradiol concentration (74.9pg∗day vs. 60.6pg∗day; P=0.002); however, there was much greater variation in follicle diameter in the group treated with GPG (7.8–22mm vs. 10.8–17.5mm in GPG+P4) and this may, at least partly explain why only 7/11 cows in this group ovulated within 48h of the Day 9 GnRH injection compared to 10/10 of the cows in the GPG+P4 group. These results suggest that differences in follicular dynamics between GPG and GPG+P4 programmes are not a key driver of the difference in conception rate, but further studies are required to better assess the role of ovulation synchronisation.

Select and treat at laparoscopy and dye test improves the spontaneous pregnancy

Infertility affects 1 in 7 couples in the UK. Tubal patency tests are an important part of infertility investigations. We conducted this observational study to determine the interval between a laparoscopy and dye test and spontaneous conception in women with unexplained infertility and minimal to mild endometriosis and pelvic adhesions treated during the procedure. The clinical records of 432 women coded as having had a laparoscopy and dye test or laparoscopy and tubal patency test between April 2007 and March 2010 were retrieved from a computerised theatre database. Pregnancies were identified through a computerised maternity booking system. Spontaneous pregnancies were recorded in 162 women following surgery (37.5%). There was a significant difference in conception rates between women with unexplained infertility and those with minor abnormalities treated at the time of diagnosis (43% vs. 58%, p = 0.019). Eighty percent of women who conceived spontaneously achieved their pregnancy within 18 months of surgery. A high proportion of women with unexplained infertility or minor abnormalities treated at the time of a laparoscopy and dye test conceived spontaneously within 12 months.

Effect of Postbreeding Intramuscular Administration of Deslorelin Acetate on Plasma LH and Progesterone Concentrations and Conception Rate in Mares.

ABSTRACTTo clarify effect of postbreeding intramuscular administration of deslorelin on mares, plasma LH and progesterone concentrations and conception rate were evaluated. In Experiment 1, deslorelin, buserelin, or a placebo was administered on day 9 (day 0=day of last breeding or AI). Plasma samples were collected daily from days 6 to 15, and additional samples were taken after treatment. There was a significant increase in hormonal concentrations after deslorelin treatment. In Experiment 2, deslorelin or placebo was injected on day 9. There was no difference in conception rates at days 15 and 30 between the two groups. While a single postbreeding treatment of deslorelin increased peripheral LH and progesterone concentrations, it may not affect the conception rate in mares.