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Journal of Dairy Science Sep 2023Our objective was to compare reproductive outcomes of primiparous lactating Holstein cows of different genetic merit for fertility submitted for insemination with...
Effect of reproductive management programs that prioritized artificial insemination at detected estrus or timed artificial insemination on the reproductive performance of primiparous Holstein cows of different genetic merit for fertility.
Our objective was to compare reproductive outcomes of primiparous lactating Holstein cows of different genetic merit for fertility submitted for insemination with management programs that prioritized artificial insemination (AI) at detected estrus (AIE) or timed AI (TAI). Moreover, we aimed to determine whether subgroups of cows with different fertility potential would present a distinct response to the reproductive management strategies compared. Lactating primiparous Holstein cows (n = 6 commercial farms) were stratified into high (Hi-Fert), medium (Med-Fert), and low (Lo-Fert) genetic fertility groups (FG) based on a Reproduction Index value calculated from multiple genomic-enhanced predicted transmitting abilities. Within herd and FG, cows were randomly assigned either to a program that prioritized TAI and had an extended voluntary waiting period (P-TAI; n = 1,338) or another that prioritized AIE (P-AIE; n = 1,416) and used TAI for cows, not AIE. Cows in P-TAI received first service by TAI at 84 ± 3 d in milk (DIM) after a Double-Ovsynch protocol, were AIE if detected in estrus after a previous AI, and received TAI after an Ovsynch-56 protocol at 35 ± 3 d after a previous AI if a corpus luteum (CL) was visualized at nonpregnancy diagnosis (NPD) 32 ± 3 d after AI. Cows with no CL visualized at NPD received TAI at 42 ± 3 d after AI after an Ovsynch-56 protocol with progesterone supplementation (P4-Ovsynch). Cows in P-AIE were eligible for AIE after a PGF treatment at 53 ± 3 DIM and after a previous AI. Cows not AIE by 74 ± 3 DIM or by NPD 32 ± 3 d after AI received P4-Ovsynch for TAI at 74 ± 3 DIM or 42 ± 3 d after AI. Binary data were analyzed with logistic regression, count data with Poisson regression, continuous data by ANOVA, and time to event data by Cox's proportional hazard regression. Pregnancy per AI (P/AI) to first service was greater for cows in the Hi-Fert (59.8%) than the Med-Fert (53.6%) and Lo-Fert (47.7%) groups, and for the P-TAI (58.7%) than the P-AIE (48.7%) treatment. Overall, P/AI for all second and subsequent AI combined did not differ by treatment (P-TAI = 45.2%; P-AIE = 44.5%) or FG (Hi-Fert = 46.1%; Med-Fert = 46.0%; Lo-Fert = 42.4%). The hazard of pregnancy after calving was greater for the P-AIE than the P-TAI treatment [hazard ratio (HR) = 1.27, 95% CI: 1.17 to 1.37)], and for the Hi-Fert than the Med-Fert (HR = 1.16, 95% CI: 1.05 to 1.28) and Lo-Fert (HR = 1.34, 95% CI: 1.20 to 1.49) groups. More cows in the Hi-Fert (91.2%) than the Med-Fert (88.4%) and Lo-Fert (85.8%) groups were pregnant at 200 DIM. Within FG, the hazard of pregnancy was greater for the P-AIE than the P-TAI treatment for the Hi-Fert (HR = 1.41, 95% CI: 1.22 to 1.64) and Med-Fert (HR = 1.28, 95% CI: 1.12 to 1.46) groups but not for the Lo-Fert group (HR = 1.13, 95% CI: 0.98 to 1.31). We conclude that primiparous Holstein cows of superior genetic merit for fertility had better reproductive performance than cows of inferior genetic merit for fertility, regardless of the type of reproductive management used. In addition, the effect of programs that prioritized AIE or TAI on reproductive performance for cows of superior or inferior genetic merit for fertility depended on the outcomes evaluated. Thus, programs that prioritize AIE or TAI could be used to affect certain outcomes of reproductive performance or management.
Topics: Pregnancy; Female; Cattle; Animals; Lactation; Estrus Synchronization; Gonadotropin-Releasing Hormone; Dinoprost; Reproduction; Fertility; Estrus; Progesterone; Insemination, Artificial
PubMed: 37474363
DOI: 10.3168/jds.2022-22673 -
Microbiology Spectrum Dec 2023Emerging evidence suggests that microbiome-targeted approaches may provide a novel opportunity to reduce the incidence of reproductive failures in cattle. To develop...
Sequencing and culture-based characterization of the vaginal and uterine microbiota in beef cattle that became pregnant or remained open following artificial insemination.
Emerging evidence suggests that microbiome-targeted approaches may provide a novel opportunity to reduce the incidence of reproductive failures in cattle. To develop such microbiome-based strategies, one of the first logical steps is to identify reproductive microbiome features related to fertility and to isolate the fertility-associated microbial species for developing a future bacterial consortium that could be administered before breeding to enhance pregnancy outcomes. Here, we characterized the vaginal and uterine microbiota in beef cattle that became pregnant or remained open via artificial insemination and identified microbiota features associated with fertility. We compared similarities between vaginal and uterine microbiota and between heifers and cows. Using culturing, we provided new insights into the culturable fraction of the vaginal and uterine microbiota and their antimicrobial resistance. Overall, our findings will serve as an important basis for future research aimed at harnessing the vaginal and uterine microbiome for improved cattle fertility.
Topics: Pregnancy; Cattle; Animals; Female; Reproduction; Vagina; Insemination, Artificial; Fertility; Microbiota
PubMed: 37921486
DOI: 10.1128/spectrum.02732-23 -
Theriogenology Jan 2021In sheep, cervical artificial insemination (AI) involves depositing semen at the cervical opening, as it is not possible to traverse the cervix due to its complex...
In sheep, cervical artificial insemination (AI) involves depositing semen at the cervical opening, as it is not possible to traverse the cervix due to its complex anatomy. However, internationally this method yields low pregnancy rates when frozen-thawed semen is used. An exception to this is in Norway, in which vaginal deposition of frozen-thawed semen to a natural estrus yields pregnancy rates around 70%. As the cervix and its secretions are the principal factors influencing sperm transport to the site of fertilization the aim of this study was to characterise the differences in the cervical anatomy as well as the cervicovaginal mucus properties of six European ewe breeds across three countries known to have differences in pregnancy rates following cervical AI with frozen-thawed semen. These were Suffolk and Belclare in Ireland, Fur and Norwegian White Sheep (NWS) in Norway and Ile de France and Romanov in France (n = 28-30 ewes/breed). Cervicovaginal mucus was collected at the follicular and luteal phases of both a synchronized and natural cycle and assessed for mucus weight, viscosity and colour. The anatomical characteristics of the cervix (length of the cervix, number of cervical rings and the appearance of the external os) were assessed post-mortem. There was a type of the cycle by ewe breed interaction represented by no differences in mucus production between ewe breeds at the natural cycle for both the follicular and luteal phases of the cycle. However, there were differences between ewe breeds at the synchronized cycle (P < 0.05). Belclare had the lowest mucus production at the follicular phase while NWS had the lowest amount of mucus at the luteal phase of the synchronized cycle. Overall, across all ewe breeds, mucus production was higher at the follicular than at the luteal phase (P < 0.05). Despite reports of Suffolk and NWS having the most divergent pregnancy rates following cervical AI with frozen-thawed semen, both breeds had the lowest overall mucus viscosity at the follicular phase of both types of cycle with no differences between both ewe breeds (P > 0.05). The length of the cervix, number of cervical rings and the external os type were affected by ewe breed (P < 0.05). Suffolk ewes had longer cervices but lower number of cervical rings than NWS and Fur ewes (both with higher pregnancy rates). In conclusion, while mucus production and mucus viscosity was affected by breed, these changes are not consistent with the known differences between ewe breeds in their pregnancy rates following cervical AI with frozen-thawed semen.
Topics: Animals; Cervix Uteri; Female; France; Insemination, Artificial; Male; Mucus; Pregnancy; Semen Preservation; Sheep; Sheep, Domestic
PubMed: 33166851
DOI: 10.1016/j.theriogenology.2020.10.038 -
Journal of Dairy Science Jan 2021The objective of this study was to compare the effects of different lengths of ovulation synchronization protocols using 2 controlled internal drug release (CIDR)... (Comparative Study)
Comparative Study
Increasing the length of an estradiol with progesterone timed artificial insemination protocol with 2 controlled internal drug release devices improves pregnancy per artificial insemination in lactating dairy cows.
The objective of this study was to compare the effects of different lengths of ovulation synchronization protocols using 2 controlled internal drug release (CIDR) devices on ovarian dynamics and pregnancy outcomes in lactating dairy cows. Lactating Holstein cows (n = 1,979) were randomly assigned to receive timed artificial insemination (TAI; d 0) following 1 of 2 treatments: (1) 9-d protocol (n = 988; 9D) with 2 intravaginal devices containing 1.9 g of progesterone (CIDR) and 2.0 mg of estradiol benzoate on day -11; 25 mg (i.m.) of dinoprost tromethamine (PG) and withdrawal of 1 CIDR on d -4; 1.0 mg (i.m.) of estradiol cypionate, second CIDR withdrawal, and PG on d -2; and TAI on d 0 and (2) 10-d protocol (n = 991; 10D) with 2 CIDR and 2.0 mg of estradiol benzoate on d -12; 25 mg of PG and withdrawal of 1 CIDR on d -4; 1.0 mg of estradiol, second CIDR withdrawal, and PG on d -2; and TAI on d 0. There was no effect of protocol on estrus detection, whereas a greater percentage of cows from 10D had ovulated close to TAI [no corpus luteum (CL) at AI and a CL at d 7] versus cows assigned to 9D protocol. A protocol × heat stress (average cow temperature ≥39.1°C on day of AI and d 7) interaction was observed in a manner that pregnancy per AI (P/AI) was greater in non-heat-stressed 10D versus 9D cows, whereas P/AI did not differ when cows were under heat stress. Furthermore, 10D protocol did not increase P/AI when all cows that received AI were included in the analysis or in cows that ovulated near TAI. However, animals assigned to 9D without any event of heat stress had a reduced P/AI when compared with cows assigned to 10D without heat stress. A protocol × CL presence at the beginning of the protocol interaction was observed and cows with a CL at the beginning of the protocol had a greater P/AI in 10D versus 9D; meanwhile, in cows without a CL, no differences on P/AI were observed. The protocol × CL presence at the beginning of the protocol interaction on P/AI was also observed for cows that ovulated near TAI. A greater percentage of cows assigned to 9D had follicles of medium size (13-15.9 mm), and greater percentage of cows assigned to 10D had larger follicles (>16 mm). Increasing the length of an estradiol with progesterone-based ovulation synchronization protocol (10D vs. 9D) increased the proportion of cows with larger follicles (>16 mm) and increased P/AI in cows without heat stress and in cows with a CL at beginning of the protocol. Moreover, the 10D protocol increased the proportion of cows with ovulation near TAI, demonstrating the effectiveness of this protocol in improving the reproductive performance of lactating Holstein cows.
Topics: Animals; Cattle; Corpus Luteum; Dinoprost; Drug Liberation; Estradiol; Estrogens; Female; Insemination, Artificial; Lactation; Ovary; Ovulation; Pregnancy; Progesterone; Time Factors
PubMed: 33131810
DOI: 10.3168/jds.2020-18872 -
Scientific Reports Nov 2021Dairy farming in tropical climates is challenging as heat stress can impair reproduction in cows. Previous studies have demonstrated the beneficial effects of...
Dairy farming in tropical climates is challenging as heat stress can impair reproduction in cows. Previous studies have demonstrated the beneficial effects of beta-carotene supplementation on bovine reproductive performance. This study was performed in Thailand, where the temperature-humidity index (THI) during the experimental periods was measured to range from 78.4 to 86.1. Lactating Holstein cows classified as repeat breeders (previous artificial insemination [AI] failures) were randomly assigned into two treatments, control treatment (T1; received placebo, n = 200) and test treatment (T2; received 400 mg/h/day of beta-carotene, n = 200). All cows were subjected to a protocol for synchronization of ovulation and timed artificial insemination (TAI). The day of the 1st ovulation synchronized protocol was defined as day 0, and the total experimental period was 160 days. Daily placebo or beta-carotene supplements were given orally on day 0 and each subsequent day of the experiment. Diagnosis of pregnancy was performed using ultrasound on day 30 after insemination. Non-pregnant cows were subjected to further ovulation synchronizations (maximum of four) and TAI over a period of 160 days. Milk samples were collected every ten days throughout the experiment. The samples were analyzed for beta-carotene concentration, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. The pregnancies per AI of the cows in T2 were significantly greater than that of T1 from the 2nd to 4th TAI. During the entire experimental period, the pregnancies in T2 were significantly greater than that of T1. Cox's proportional hazards regression model data indicated a 44% greater probability of pregnancy for cows receiving beta-carotene. The concentrations of milk beta-carotene in T2 were significantly greater than T1 from the 2nd to 4th TAI. Significantly greater SOD and GPx activities were observed in T2 than T1, suggesting a reduction of oxidative stress in cows treated with beta-carotene. Dietary supplementation with beta-carotene thus improves the reproductive performance of repeat breeders exposed to heat stress, possibly by reducing oxidative stress.
Topics: Animal Feed; Animals; Biotechnology; Cattle; Dietary Supplements; Dinoprost; Estrus Synchronization; Female; Gonadotropin-Releasing Hormone; Humidity; Insemination, Artificial; Lactation; Least-Squares Analysis; Ovulation; Pregnancy; Pregnancy, Animal; Progesterone; Proportional Hazards Models; Regression Analysis; Reproduction; Temperature; Thailand; beta Carotene
PubMed: 34848807
DOI: 10.1038/s41598-021-02655-8 -
JBRA Assisted Reproduction Jan 2022The global increase in subfertility diagnosis and treatments and the rise of private equity investors concentrating on high profits based on in vitro fertilisation (IVF)...
The global increase in subfertility diagnosis and treatments and the rise of private equity investors concentrating on high profits based on in vitro fertilisation (IVF) treatments raise profound societal and economic questions for stakeholders and patients. The question remains as to whose benefits will ultimately be greater when promoting high margins treatment options resulting from cross-border mergers and acquisitions of IVF clinics.This paper covers wide-ranging issues from the erroneously constructed UK National Institute for Health and Care Excellence's (NICE) guidelines on treatment choices, the cost-effectiveness of treatments, the promotion of IVF, and add-ons where evidence remains minimal, the commercial size of the fertility industry. Investment in improving intrauterine insemination (IUI) success rates has understandably been avoided for its short-term impact on the IVF industry. However, IUI efficiency would cut across many of the global subfertility treatment economic and access problems while allowing stakeholder, feepaying, and patients financial savings will likely allow for more funded IVF cycles in acutely deserving cases. The recommendations will help expand choices for globally economically challenged patients' and services while enhancing an ethical and moral dimension towards fertility treatment choices for patients and stakeholders.
Topics: Cost-Benefit Analysis; Fertilization in Vitro; Humans; Infertility; Insemination, Artificial; Ovulation Induction
PubMed: 35040304
DOI: 10.5935/1518-0557.20210111 -
Animal : An International Journal of... Jul 2020Triptorelin (TRI), a gonadotropin-releasing hormone agonist allowing ovulation synchronization in pigs, is indispensable for fixed-time artificial insemination (FTAI)... (Meta-Analysis)
Meta-Analysis
Triptorelin (TRI), a gonadotropin-releasing hormone agonist allowing ovulation synchronization in pigs, is indispensable for fixed-time artificial insemination (FTAI) protocols. However, the effect of FTAI using TRI (FTAI-TRI) on the reproductive performance is controversial. We performed a meta-analysis to determine whether FTAI-TRI affects reproductive performance of pigs, including pregnancy rate (PR), number of pigs born alive per litter (NBA), farrowing rate (FR) and total number of pigs born per litter (TNB). A total of 37 trials from 15 studies were extracted and analysed in Stata. A weighted mean difference (WMD) with 95% confidence interval (CI) was calculated for NBA and TNB, and risk ratio (RR) with 95% CI was calculated for PR and FR. Pregnancy rate, TNB and NBA data were applied to a fixed-effect protocol, and FR data were applied to a random-effect protocol. We found that for weaned sows, the FTAI-TRI group had comparable reproductive performance to the artificial insemination (AI) following oestrus detection (EDAI) group. Fixed-time AI has many advantages, including the elimination of the need to heat-check twice daily, so that FTAI-TRI is a good substitute for EDAI. Subgroup analysis indicated that the optimal timing of triptorelin treatment was 96 h after weaning, which gave significant positive effects on PR (RR = 1.08, P = 0.000) and non-significant positive effects on TNB (WMD = 0.12, P = 0.452). Triptorelin at a dose of 100 μg showed better effects than 200 μg, with significant positive effects on PR (RR = 1.09, P = 0.005) and FR (RR = 1.06, P = 0.036). So a single dose of 100 μg was recommended. The optimal protocol was insemination at 24 h and again at 48 h after triptorelin administration if they remained in standing oestrus, and this provided a significantly higher NBA (WMD = 0.59, P = 0.013) that increased by 0.59. For gilts, the FTAI-TRI group showed decreased (not significant) PR (RR = 0.96, P = 0.127) and significantly decreased FR (RR = 0.93, P = 0.013), TNB (WMD = -0.85, P = 0.006) and NBA (WMD = -0.98, P = 0.000), which were inferior to those in the EDAI group. In conclusion, the effects of FTAI-TRI on the reproductive performance of pigs were parity-, treatment timing-, insemination timing-, and dosage-dependent. Fixed-time AI using triptorelin could effectively replace the EDAI protocol for sows, but not for gilts.
Topics: Animals; Estrus; Estrus Detection; Estrus Synchronization; Female; Insemination, Artificial; Pregnancy; Reproduction; Swine; Triptorelin Pamoate
PubMed: 31858952
DOI: 10.1017/S1751731119003008 -
Journal of Genetics 2020Karyotyping is one among the culling parameter used for taking up culling decisions. Cytogenetic screening of breeding bulls has been recommended to screen for...
Karyotyping is one among the culling parameter used for taking up culling decisions. Cytogenetic screening of breeding bulls has been recommended to screen for chromosomal abnormalities before semen production in artificial insemination. The chromosomal analysis of a Holstein Friesian crossbred bull revealed the presence of acrocentric Y-chromosome, which was further confirmed by CBG banding. The shape of the Y-chromosome determining that male line used for crossbreeding was from indigenous origin. Karyotyping is a best and reliable technique for the identification of crossbred calves born to the indigenous bulls.
Topics: Animals; Breeding; Cattle; Chromosome Aberrations; Hybridization, Genetic; Insemination, Artificial; Karyotyping; Male; Semen; Y Chromosome
PubMed: 32482916
DOI: No ID Found -
Journal of Dairy Science Jun 2023The use of assisted-reproduction technologies such as in vitro fertilization (IVF) is increasing, particularly in dairy cattle. The question of consequences in later...
The use of assisted-reproduction technologies such as in vitro fertilization (IVF) is increasing, particularly in dairy cattle. The question of consequences in later life has not yet been directly addressed by studies on large animal populations. Studies on rodents and early data from humans and cattle suggest that in vitro manipulation of gametes and embryos could result in long-term alteration of metabolism, growth, and fertility. Our goal was to better describe these presumed consequences in the population of dairy cows produced by IVF in Québec (Canada) and to compare them to animals conceived by artificial insemination (AI) or multiple ovulation embryo transfer (MOET). To do so, we leveraged a large phenotypic database (2.5 million animals and 4.5 million lactations) from milk records in Québec aggregated by Lactanet (Sainte-Anne-de-Bellevue, QC, Canada) and spanning 2012 to 2019. We identified 304,163, 12,993, and 732 cows conceived by AI, MOET, and IVF, respectively, for a total of 317,888 Holstein animals from which we retrieved information for 576,448, 24,192, and 1,299 lactations (total = 601,939), respectively. Genetic energy-corrected milk yield (GECM) and Lifetime Performance Index (LPI) of the parents of cows were used to normalize for genetic potential across animals. When compared with the general Holstein population, MOET and IVF cows outperformed AI cows. However, when comparing those same MOET and IVF cows with only herdmates and accounting for their higher GECM in the models, we found no statistical difference between the conception methods for milk production across the first 3 lactations. We also found that the rate of Lifetime Performance Index improvement of the IVF population during the 2012 to 2019 period was less than the rate observed in the AI population. Fertility analysis revealed that MOET and IVF cows also scored 1 point lower than their parents on the daughter fertility index and had a longer interval from first service to conception, with an average of 35.52 d compared with 32.45 for MOET and 31.87 for AI animals. These results highlight the challenges of elite genetic improvement while attesting to the progress the industry has made in minimizing epigenetic disturbance during embryo production. Nonetheless, additional work is required to ensure that IVF animals can maintain their performance and fertility potential.
Topics: Female; Humans; Cattle; Animals; Milk; Fertility; Fertilization; Fertilization in Vitro; Lactation; Insemination, Artificial; Embryo Transfer; Ovulation
PubMed: 37028966
DOI: 10.3168/jds.2022-22736 -
Animal : An International Journal of... Feb 2021Numerous meat sheep breeding programs in developed and developing countries are characterized by incomplete sire information and a predominant use of natural matings....
Numerous meat sheep breeding programs in developed and developing countries are characterized by incomplete sire information and a predominant use of natural matings. These two parameters potentially affect the benefit of genomic selection (GS), especially for the selection of a late-in-life trait. Using stochastic simulations, the genetic gains obtained using genomic and conventional strategies for a maternal trait were evaluated in meat sheep population. Natural mating and artificial insemination (AI)-based designs, inspired by the current diversity of designs used for French meat sheep breeds, were modeled and three genomic strategies were tested and compared with a conventional selection strategy: parentage assignment, GS based on a male or a male and female reference population. Genomic selection based on a male reference population did not always outperform conventional selection. Its benefit depended on the design, the level of missing information on dam sires, and the level of AI. Genomic selection based on a male and female reference population always outperformed the conventional selection strategy, even if only 25 % of the females in the nucleus were genotyped.
Topics: Animals; Female; Genome; Genomics; Insemination, Artificial; Male; Meat; Selection, Genetic; Sheep
PubMed: 33573971
DOI: 10.1016/j.animal.2020.100040