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Journal of Dairy Science Apr 2022This study used a stochastic simulation model to estimate the potential economic benefit of using timed artificial insemination (TAI) in combination with conventional...
This study used a stochastic simulation model to estimate the potential economic benefit of using timed artificial insemination (TAI) in combination with conventional unsorted (TCONV) and sexed (TSEX) semen in heifers only (TCONV-H, TSEX-H) and in both heifers and lactating cows (TCONV-HC, TSEX-HC) in a high-producing, pasture-based production system. The scenarios were compared with a conventional reproductive policy (CONV) in which heifers and cows were inseminated with conventional unsorted semen after estrus detection. Sensitivity analysis was also used to estimate the effect of hormone costs from TAI use on the profitability of each program relative to CONV. The mean annual (± standard deviation) profit advantage (ΔPROF) over CONV for TCONV-H, TCONV-HC, TSEX-H, and TSEX-HC scenarios were €3.90/cow ± 4.65, €34.11/cow ± 25.69, €13.96/cow ± 6.83, and €41.52/cow ± 42.86, respectively. Combined application of both technologies was shown to return a greater annual ΔPROF on average compared with that achievable from TAI alone. However, the risk of not returning a positive annual ΔPROF varied across the scenarios with higher risk in TCONV-H and TSEX-HC. Specifically, TCONV-H and TSEX-HC had a 24 and 18% chance, respectively, of not returning a positive annual ΔPROF. Sensitivity analysis showed that when hormone costs increased by €10/cow TCONV-H and TSEX-HC had a 38 and 23% chance, respectively, of not returning a positive annual ΔPROF. The range in ΔPROF for TCONV policies was most sensitive to the TAI pregnancy rate and TSEX policies were most sensitive to the relative fertility achieved with sexed compared with unsorted semen. This study has shown TAI and sexed semen are complementary technologies that can increase genetic gain and profitability in a pasture-based, dairy production system.
Topics: Animals; Cattle; Dairying; Female; Insemination, Artificial; Lactation; Pregnancy; Semen; Sex Preselection
PubMed: 35181145
DOI: 10.3168/jds.2021-21070 -
Fertility and Sterility Feb 2018Although current screening methods of gamete donors are capable of reducing the incidence of genetic anomalies in donor offspring below general population levels,... (Review)
Review
Although current screening methods of gamete donors are capable of reducing the incidence of genetic anomalies in donor offspring below general population levels, targeted screening for a large number of conditions (expanded carrier screening or ECS) could be considered as part of the routine selection procedure for gamete donors. There are, however, important drawbacks to its practical implementation. Excluding all carriers of severe recessive monogenic pediatric disorders would disqualify virtually all donors, and other approaches negatively affect cost (and therefore access), present dilemmas in regard to disclosure of genetic findings, and/or overburden the intended parents. In all of the scenarios considered, adequate genetic counseling will be of central importance. Besides looking at benefits and drawbacks of possible ways of implementing ECS, we also examine whether a moral obligation exists to adopt ECS at all and on whose shoulders such an alleged obligation would rest: policymakers, medical staff at fertility clinics, sperm and egg banks, the intended parents? We argue that given the small risk reduction brought about by ECS, the possible negative effects of its implementation, and the absence of widespread preconception carrier screening in the general population, it is inconsistent to argue that there is a moral obligation to perform ECS in the context of donor conception. Finally, implications for the donors are discussed.
Topics: Female; Fertility; Genetic Carrier Screening; Humans; Infertility; Insemination, Artificial, Heterologous; Male; Moral Obligations; Oocyte Donation; Ovum; Policy Making; Practice Guidelines as Topic; Preconception Care; Pregnancy; Risk Assessment; Risk Factors; Sperm Banks; Spermatozoa; Tissue Donors
PubMed: 29447661
DOI: 10.1016/j.fertnstert.2017.11.032 -
Journal of Dairy Science Nov 2022A 60% pregnancy success for inseminations is targeted to optimize production efficiency for dairy cows within a seasonal, pasture-grazed system. Routine measures of...
A 60% pregnancy success for inseminations is targeted to optimize production efficiency for dairy cows within a seasonal, pasture-grazed system. Routine measures of pregnancy success are widely available but are limited, in practice, to a gestation stage beyond the first 28 d. Although some historical data exist on embryonic mortality before this stage, productivity of dairy systems and genetics of the cows have advanced significantly in recent decades. Accordingly, the aim was to construct an updated estimate of pregnancy success at key developmental stages during the first 70 d after insemination. Blood samples were collected for progesterone concentrations on d 0 and 7. A temporal series of 4 groups spanning fertilization through d 70 were conducted on 4 seasonal, pasture-grazed dairy farms (n = 1,467 cows) during the first 21 d of the seasonal breeding period. Morphological examination was undertaken on embryos collected on d 7 (group E7) and 15 (group E15), and pregnancy was diagnosed via ultrasonography on approximately d 28 and 35 (group E35) as well as d 70 (group E70). Fertilization, embryo, and fetal evaluation for viability established a pregnancy success pattern. Additionally, cow and on-farm risk factor variables associated with pregnancy success were evaluated. We estimated pregnancy success rates of 70.9%, 59.1%, 63.8%, 62.3%, and 56.7% at d 7, 15, 28, 35, and 70, respectively. Fertilization failure (15.8%) and embryonic arrest before the morula stage (10.3%) were the major developmental events contributing to first-week pregnancy failures. Embryo elongation failure of 7% contributed to pregnancy failure during the second week. The risk factors for pregnancy success that were related to the cows included interval between calving and insemination, and d-7 plasma progesterone concentrations, whereas insemination sire was associated with pregnancy outcome. Most pregnancy failure occurs during the first week among seasonal-calving pasture-grazed dairy cows.
Topics: Female; Cattle; Pregnancy; Animals; Lactation; Progesterone; Milk; Pregnancy Outcome; Insemination; Insemination, Artificial; Reproduction
PubMed: 36153157
DOI: 10.3168/jds.2021-21773 -
BMC Veterinary Research Mar 2019Bovine brucellosis is a zoonotic disease that causes substantial economic losses and has a strong impact on public health. The main objective of this paper is to...
BACKGROUND
Bovine brucellosis is a zoonotic disease that causes substantial economic losses and has a strong impact on public health. The main objective of this paper is to determine the risk factors for new infections of Brucella abortus on Colombian cattle farms previously certified as being free of brucellosis. A case-control study was conducted by comparing 98 cases (farms certified as brucellosis-free for three or more years but became infected) with 93 controls (farms that remained brucellosis-free during at least the previous three years). The farms were matched by herd size and geographical location (municipality). Information was obtained via a questionnaire completed by veterinary officers through a personal interview with the herd owners.
RESULTS
Two-thirds of the herds (67%) were dairy herds, 16% were beef herds, and 17% were dual-purpose (beef and milk) herds. After exploratory univariate analysis, all explanatory variables with a p-value of ≤0.20 were included in a logistic regression model using the forward stepwise method to select the model with the best goodness of fit. The significant risk factors were the replacement of animals from farms not certified as brucellosis-free compared to replacement from certified brucellosis-free farms (OR = 4.84, p-value < 0.001) and beef cattle farms compared to dairy cattle farms (OR = 3.61, p-value = 0.017). When herds with and without artificial insemination were compared, it was observed that farms that used natural breeding with bulls from non-certified herds had a higher risk than farms using artificial insemination (OR = 2.45, p-value = 0.037), but when the bulls came from brucellosis-free farms, farms with natural breeding were less affected (OR = 0.30, p-value = 0.004) than farms using artificial insemination, whether with frozen semen from certified brucellosis-free herds or fresh semen from uncontrolled herds. The latter is commonly sold to neighbouring farms.
CONCLUSIONS
The government should make efforts to inform farmers about the risks involved in the introduction of semen and replacement heifers from farms that are not certified as brucellosis-free and to establish measures to control these practices.
Topics: Animal Husbandry; Animals; Breeding; Brucella abortus; Brucellosis, Bovine; Cattle; Colombia; Cryopreservation; Dairying; Female; Insemination, Artificial; Male; Risk Factors; Semen Preservation
PubMed: 30845954
DOI: 10.1186/s12917-019-1825-9 -
PloS One 2023Early pregnancy diagnosis is key to maximise productivity of dairy herds. We previously showed that an increase in the levels of miR-26 could be detected as soon as day...
Early pregnancy diagnosis is key to maximise productivity of dairy herds. We previously showed that an increase in the levels of miR-26 could be detected as soon as day 8 of pregnancy in heifers. The aims of this study were to determine whether 1) plasma miR-26 levels would be distinctly elevated, retrospectively, early after artificial insemination in lactating cows with successful compared to failed pregnancies, 2) the early increase in miRNA levels in cows with successful pregnancy could be accounted for by changes in miRNA expression in white blood cells (WBCs), presumably induced by the effects of embryo-derived interferon tau (IFNt), and 3) plasma miRNA levels may provide a reliable early predictor of pregnancy that could be used at a herd level. Blood samples were taken from a total of 34 dairy cows (lactation number 1 to 4) before (D0) and 9 and 18 days after artificial insemination at oestrus, followed by confirmation of pregnancy status by ultrasound on D32. In addition, WBCs collected from non-pregnant cows (n = 4) were stimulated in vitro with recombinant ovine IFNt (0-100 pg/ml). Levels of miRNAs and ISG15, a known IFNt-induced gene, were quantified by qPCR. Relative to D0, a larger increase in plasma miR-26a (P = 0.04) occurred on D9 in cows later confirmed to be pregnant (n = 12) than in cows with a failed pregnancy (n = 22). Expression of miR-26a in WBCs was not affected (P>0.1) by pregnancy status or IFNt stimulation in vitro, in contrast to ISG15 expression which increased markedly (P<0.0001) both in WBC samples collected on D18 from animals later confirmed to be pregnant, and in WBCs after stimulation with IFNt in vitro. Finally, ROC analyses revealed that miR-26a on D9 or D18 could predict pregnancy outcome with much lower accuracy than WBC ISG15 on D18 (Likelihood ratio, 2.3 vs 15.4). In summary, a modest increase in plasma miR-26a levels occurs during early pregnancy in mature dairy cows which may not accounted for by changes in miRNA levels in WBCs or the effects of IFNt. Moreover, compared to ISG15, changes in miR-26a levels may not provide an accurate test for early diagnosis of pregnancy in cows.
Topics: Pregnancy; Cattle; Animals; Female; Sheep; Pregnancy Outcome; Lactation; Retrospective Studies; Insemination, Artificial; MicroRNAs; Progesterone
PubMed: 37566616
DOI: 10.1371/journal.pone.0289342 -
BMC Veterinary Research Jun 2023Difference in breed, nutrition status and climate in which animals are managed result in differences in response to reproductive hormones. Fertility rate to artificial...
Ovarian response and conception rate in Boran and Boran*Holstein cows treated by Gonadotrophin-realizing hormone and ProstaglandinF2α with and without exogenous progesterone.
BACKGROUND
Difference in breed, nutrition status and climate in which animals are managed result in differences in response to reproductive hormones. Fertility rate to artificial insemination is very low in Ethiopian Boran and Boran*Holstein crosses. This partly maybe due to adopting estrus and/or ovulation synchronization developed for temperate taurine cattle. Experimental study was conducted to evaluate ovarian response to combinations of Gonadotrophin-Realizing Hormone agonist (gonadorelin) and ProstaglandinF2α (PGF2α) with or without progesterone (Controlled Internal Drug Release/CIDR), and conception rate to timed AI. Postpartum native Ethiopian Boran (n = 60) and Boran*Holstein cross (n = 66) cows were randomly assigned to four treatment groups as Ovsynch (gonadorelin on day of start, PGF2α seven days later, 2nd gonadorelin at 48 h of PGF2α and insemination at 19 h of the 2nd gonadorelin); CIDR + Ovsynch (same as Ovsynch but CIDR device was inserted into vagina for 7 days); Cosynch (same as Ovsynch but insemination was made at the 2nd gonadorelin) and CIDR + Cosynch (same as Cosynch but CIDR was inserted for 7 days).
RESULT
There was no difference (P > 0.05) in ovulation rate to day 9 gonadorelin (88.33% in Boran; 78.79% in Boran*Holstein) and interval from day 9 gonadorelin to ovulation (36.5 ± 1.13 h in Boran and 36.057 ± 1.11 h in Boran*Holstein). Dominant follicle immediate to ovulation (14.95 ± 0.19 mm Vs 19.12 ± 0.49 mm) and corpus luteum size (16.31 ± 0.33 mm Vs 20.28 ± 0.43 mm ) respectively were smaller (P < 0.05) in Boran than Boran*Holstein. Plasma progesterone concentration at PGF2α was higher (P < 0.05) in Boran (11.91 ± 0.74ng/mL) than Boran*Holstein (6.13 ± 0.27ng/mL) but luteolysis rate was lower (P < 0.05) in Boran (87.9%) than Boran-Holstein (96.9%). Cows with CIDR had higher conception rate than cows without CIDR (72.00% Vs 39.02% in Boran*Holstein and 74.07%, Vs 51.52% in Boran respectively). Insemination at 19 h of gonadorelin administration resulted in higher conception rate (78.6% for Boran; 71.43% for Boran*Holstein) than insemination at gonadorelin (69.29% for Boran; 66.67% for Boran*Holstein).
CONCLUSION
Boran cows have smaller preovulatory follicles, smaller corpus luteum, large amount of progesterone and lower rate of luteolysis to PGF2α compared to Boran*Holstein. The CL of Boran cattle seems les reactive to PGF2α than Boran*Holstein CL. CIDR significantly improved conception rate in Boran and Boran*Holstein cows.
Topics: Female; Cattle; Animals; Progesterone; Dinoprost; Estrus Synchronization; Lactation; Gonadotropin-Releasing Hormone; Insemination, Artificial
PubMed: 37264362
DOI: 10.1186/s12917-023-03617-0 -
Journal of Animal Science Jul 2022Recently, interest in supplementing vitamin D (Vit D) to improve aspects of health, mainly in human fertility, has emerged. Still, supplementation of Vit D above the...
Recently, interest in supplementing vitamin D (Vit D) to improve aspects of health, mainly in human fertility, has emerged. Still, supplementation of Vit D above the minimum required levels has yet to be explored in cattle despite evidence for Vit D receptors in reproductive tissues. The objective of this study was to establish if a dose-response relationship exists between Vit D exposure and success of in vitro production (IVP) of embryos and, if acute supplementation of Vit D improves pregnancy rates during timed artificial insemination (TAI) of dairy cows. Cumulus-oocyte complexes (COCs) were obtained from ovaries acquired from a local abattoir and cultured in five different IVP treatments from three separate collections (Control, 50, 100, 150, and 200 ng/mL of 1,25(OH)2D3; n = 20-30 COCs/group). In Experiment 2, dairy breed cows (n = 100) were synchronized for TAI with the PresynchOvsynch protocol. Cows received 150,000 IU of Vit D (n = 48) or castor oil as control (n = 53) along with gonadotropin-releasing hormone (GnRH) 24 h before TAI. Serum samples were collected before and 24 h after treatment. A small cohort of cows (n = 4) received the same treatments in two separate cycles and follicular fluid (FF) was collected after 24 h for calcidiol (25OHD) analyses. Increased concentrations of Vit D resulted in decreased rates of maturation of COC (150 and 200 ng/mL vs. control and 50 ng/mL; P = 0.01). Supplementation with 50 ng/mL resulted in greater numbers of early blastocyst and blastocyst stage embryos (P < 0.009). Pregnancy at first breeding did not differ (P = 0.13) between groups, but serum 25OHD increased in treated females after 24 h (P = 0.002). The FF 25OHD levels were reflective of serum levels, however, the observed increase in the treatment cycle (P = 0.04) was parallel to an overall increase in serum 25OHD during the entire second cycle, likely due to increased environmental sunlight exposure (March, control vs. May, treatment). A similar increase in the serum 25OHD in the lactating commercial herd maintained in covered housing was not observed, although experiments were conducted during a similar timeframe. This herd had levels of 25OHD near the low end of sufficiency according to National Research Council (NRC) guidelines. We conclude mild Vitamin D supplementation with concentrations at the higher end of NRC guidelines can improve maturation rates of recovered COCs. However, longer term supplementation may be needed to appreciate any benefits on fertility.
Topics: Animals; Cattle; Dinoprost; Estrus Synchronization; Female; Fertility; Fertilization; Gonadotropin-Releasing Hormone; Insemination, Artificial; Lactation; Ovulation; Pregnancy; Progesterone; Vitamin D
PubMed: 35772760
DOI: 10.1093/jas/skac168 -
The Journal of Veterinary Medical... Nov 2018This study was conducted on red foxes to determine the appropriate voltage in electroejaculation for semen collection from stud males, and to confirm whether frozen...
This study was conducted on red foxes to determine the appropriate voltage in electroejaculation for semen collection from stud males, and to confirm whether frozen semen with bovine semen extender can be used for artificial insemination. The proper load voltage for electroejaculation was 3-4 V based on semen collection rates and concentrations of spermatozoa. Frozen semen was prepared according to the known procedure for cows. In frozen-thawed semen, a relatively high conception rate (81.3%) was obtained in vixens, in which the optimum insemination time was detected by vaginal electrical resistance. These findings demonstrate that the restricted condition for semen collection by electroejaculation with cryopreservation of semen using bovine semen extender can be applied to artificial insemination of red foxes.
Topics: Animals; Cell Survival; Cryopreservation; Ejaculation; Electric Stimulation; Foxes; Freezing; Insemination, Artificial; Male; Semen; Semen Preservation; Spermatozoa
PubMed: 30249927
DOI: 10.1292/jvms.17-0433 -
Reproduction in Domestic Animals =... Dec 2021The objective of this project was to report the effects of season and age on conception rate amongst Italian Mediterranean Buffalo subjected to an Ovsynch/Resynch (O/R)...
Effects of age and season on conception rate of Mediterranean Italian Dairy Buffalo (Bubalus bubalis) following oestrus synchronization and fixed-time artificial insemination.
The objective of this project was to report the effects of season and age on conception rate amongst Italian Mediterranean Buffalo subjected to an Ovsynch/Resynch (O/R) reproductive management protocol. The study utilized nulliparous (heifers), primiparous buffalo cows (PBC) and multiparous buffalo cows (MBC). The primiparous and multiparous groups were subjected to the synchronization protocol throughout the entire year, but heifers were synchronized and inseminated only during the spring/summer seasons. The conception rate obtained following the OvSynch oestrus synchronization protocol, applied during spring, was 68.4% for heifers, 83.3% for PBC and 67.7% for MBC. The overall total conception rates following the complete O/R protocol were 84.27%, 94.4% and 79%. Conception rates achieved during summer were heifers 52%, PBC 47.2% and MBC 49%, whilst overall conception rates following the full O/R protocol were 72%, 69.8% and 58.2% respectively. In the autumn seasons, PBC conceived 58.9% and MBC 52.1% following initial Ovsynch, which improved to total overall conception rates of 87.5% and 78.7% following the full O/R protocol. Similarly, in the winter season, PBC experienced a conception rate of 47.5% following Ovsynch and 72.5% after a follow-up Resynch. MBC experienced 60.0% and 74.4% conception following Ovsynch and full O/R, respectively, during winter. Total conception rates during all seasons were quite acceptable following the O/R protocol. There was a significant decrease from spring to summer in conception rate for all parity groups, but heifers were not a severely affected as older buffalo cows. This finding agrees with that of other investigators indicating that heifer fertility is not as negatively impacted by long photoperiod and higher ambient temperature as that of older animals. The O/R protocol as utilized in this study is an effective means of reproductive management for dairy buffalo cows and is effective for improving fertility during out-of-season breeding.
Topics: Animals; Buffaloes; Cattle; Dinoprost; Estrus Synchronization; Female; Fertilization; Gonadotropin-Releasing Hormone; Insemination, Artificial; Pregnancy; Seasons
PubMed: 34486776
DOI: 10.1111/rda.14013 -
Journal of Dairy Science Aug 2023Adoption of automated monitoring devices (AMD) affords the opportunity to tailor reproductive management according to the cow's needs. We hypothesized that a targeted...
Adoption of automated monitoring devices (AMD) affords the opportunity to tailor reproductive management according to the cow's needs. We hypothesized that a targeted reproductive management (TRM) would reduce the use of reproductive hormones while increasing the percentage of cows pregnant 305 d in milk (DIM). Holstein cows from 2 herds (n = 1,930) were fitted with an AMD at 251.0 ± 0.4 d of gestation. Early-postpartum estrus characteristics (EPEC; intense estrus = heat index ≥70; 0 = minimum, 100 = maximum) of multiparous cows were evaluated at 40 (herd 1) or 41 (herd 2) DIM and EPEC of primiparous cows were evaluated at 54 (herd 1) or 55 (herd 2) DIM. Control cows received the first artificial insemination at fixed time (TAI; primiparous, herd 1 = 82 and herd 2 = 83 DIM; multiparous, herd 1 = 68 and herd 2 = 69 DIM) following the Double-Ovsynch (DOV) protocol. Cows enrolled in the TRM treatment were managed as follows: (1) cows with at least one intense estrus were inseminated upon AMD detected estrus for 42 d and, if not inseminated, were enrolled in the DOV protocol; and (2) cows without an intense estrus were enrolled in the DOV protocol at the same time as cows in the control treatment. Control cows were re-inseminated based on visual or patch aided detection of estrus, whereas TRM cows were re-inseminated as described for control cows with the aid of the AMD. Cows received a GnRH injection 27 ± 3 d after insemination and, if diagnosed as nonpregnant, completed the 5-d Cosynch protocol and received TAI 35 ± 3 d after insemination. Among cows in the TRM treatment, 55.8 and 42.9% of primiparous and multiparous cows, respectively, received the first insemination in spontaneous estrus. The interaction between treatment and parity affected pregnancy 67 d after the first AI (primiparous: control = 37.6%, TRM = 27.4%; multiparous: control = 41.0%, TRM = 44.7%). The TRM treatment increased re-insemination in estrus (control = 48.3%, TRM = 70.5%). Pregnancy 67 d after re-inseminations tended to be affected by the interaction between treatment and EPEC (no intense estrus: control = 25.3%, TRM = 32.0%; intense estrus: control = 32.9%, TRM = 32.2%). The interaction between treatment and EPEC affected pregnancy by 305 DIM (no intense estrus: control = 80.8%, TRM = 88.2%; intense estrus: control = 87.1%, TRM = 86.1%). Treatment did not affect the number of reproductive hormone treatments among cows that had not had an intense estrus (control = 10.5 ± 0.3, TRM = 9.1 ± 0.2 treatments/cow), but cows in the TRM treatment that had an intense estrus received fewer reproductive hormone treatments than cows in the control treatment (2.0 ± 0.1 vs. 9.6 ± 0.2 treatments/cow). Selecting multiparous cows for first AI in estrus based on EPEC reduced the use of reproductive hormones without impairing the likelihood of pregnancy to first AI. The use of AMD for re-insemination expedited the establishment of pregnancy among cows that did not display an intense estrus early postpartum.
Topics: Pregnancy; Female; Cattle; Animals; Lactation; Estrus Synchronization; Dinoprost; Estrus Detection; Gonadotropin-Releasing Hormone; Insemination, Artificial; Progesterone
PubMed: 37349211
DOI: 10.3168/jds.2022-22666