Theriogenology February 2021 - March 2020 Flashcards
Effect of dose and timing of prostaglandin F-2 alpha treatments during a 7-d Ovsynch protocol on progesterone concentration at the end of the protocol and pregnancy outcomes in lactating Holstein cows
Tippenhauer et al., 2021
A second PGF dose on d 8 during a 7-d Ovsynch protocol decreased percentage of cows with high progesterone (P4) concentrations at G2 and increased pregnancy per AI (P/AI) compared to a single PGF dose on d 7.
Doubling the PGF dose on d 7 in a 7-d Ovsynch protocol did not affect the percentage of cows with high P4 concentration at G2 and had only a marginal effect on P/AI compared to a single PGF dose on d 7.
There was no interaction between treatment and presence of a CL at G1 on P/AI.
Presynchronized cows receiving first postpartum TAI had similarly increased P/AI treated with a double PGF dose compared to treatment with a second PGF dos
Interaction of Mycobacterium avium subsp. paratuberculosis with bovine sperm
Caldeira et al., 2020
The adhesion of MAP on bovine sperm occurs mainly in the midpiece.
MAP affects the sperm parameters.
Interaction of MAP with sperm could be linked to the 85 complex proteins
- Sperm in the presence of MAP shows a decrease in motility and vigor, and that the higher the MAP concentration, the lower the sperm performance.
- It was possible to determine the viability of MAP after cryopreservation in samples of higher concentrations, which demonstrates the potential of transmission of this pathogen through artificial insemination.
- The interaction of MAP with bovine sperm occurs mainly in the midpiece and may be linked to the proteins 85A and 85B present in the MAP membrane
Feeding yearling Angus bulls low-level ergot daily for 9 weeks decreased serum prolactin concentrations and had subtle effects on sperm end points
Chohan et al., 2021
Ergot alkaloid feeding at 3.4 mg/kg of DMI/day for 9 weeks of yearling bulls transiently reduced plasma prolactin by 4-folds.
Body weight, scrotal circumference, rectal temperature, or sperm concentrations were not remarkably affected.
Subtle effects on progressive motility, mid-piece defects, and mitochondrial membrane potential were recorded.
Current Canadian ergot standards (3 mg/kg of feed) are adequate for bull reproduction; prolactin decrease is concerning.
Cow-level prevalence and risk factors for estrus detection inaccuracy in seasonal calving pasture-based dairy cows
Kelly et al., 2021 (Mc Aloon author)
The overall cow-level prevalence of estrous detection inaccuracy was low at 4.7%.
Estrous detection inaccuracy at first AI was lower than at repeat AI.
Lack of mounting abrasions were a risk factor for detection inaccuracy at first AI.
No observed standing estrus and an abnormal preceding repeat interval were risk factors for inaccuracy at repeat AI.
Changes in miRNA levels of sperm and small extracellular vesicles of seminal plasma are associated with transient scrotal heat stress in bulls
Alves et al., 2021
Scrotal heat stress (SHS) mainly down-regulates sperm miRNA levels.
SHS changes sEVs-associated-miRNAs involved in cell biosynthesis processes.
SHS changes miR-126-5p level in sperm and small extracellular vesicles.
miR-15a, −34b, −34c, −146a, −200b and −449a are potential spermatogenesis modulators.
Monitoring estrous activity in pasture-based dairy cows
Moore et al., 2021
Correlations between FlashMate(mount detector) and Moomonitor activity (accelerometer) during estrus were weak.
Fifty-five percent of cows received contacts related to mounting activity for ≤8 h.
Pregnancy rate reduced when cows were inseminated within 2–4 h of activity onset.
Maximising body condition score and days in milk at AI increased pregnancy rates
Characterization of intrauterine cultivable aerobic microbiota at the time of insemination in dairy cows with and without mild endometritis.
Ballas et al., 2021
High uterine bacterial diversity at the time of artificial insemination.
Bacillus, Staphylococcus, Corynebacterium, and Streptococcus the most common genera.
Rare detection of uterine pathogens, such as Trueperella pyogenes.
Mild endometritis at artificial insemination decreases the chance of pregnancy.
Intrauterine antibiotic treatment shortly after AI must be scrutinized
Bovine alphaherpesvirus 1 (BHV1) infection in testes and epididymis from bulls from a slaughterhouse
Queiroz-Castro et al., 2021
BHV1 was found in the reproductive tract of bulls by immunodetection and Nested-PCR.
We bring the first evidence of BHV1 presence in testes and epididymides of naturally infected bulls.
BHV1 in the testicle and in the epididymis may be sources of infection to the semen.
The effect of altering the timing of GnRH administration and artificial insemination in a modified 5-d CO-Synch protocol using sex-sorted semen in dairy heifers
Macmillan et al., 2021
Dairy heifers were subjected to a modified 5-d CO-Synch TAI protocol.
Giving GnRH 16 h before or at the time of AI did not affect P/AI.
Heifers in early estrus were AI 16 h earlier, tending to improve overall P/AI.
Delaying AI by 8 h increased estrus rates but did not improve P/AI.
Across both experiments, P/AI was increased in heifers that displayed estrus before AI compared with heifers that did not
Farm and cow factors and their interactions on the incidence of retained placenta in holstein dairy cows
Mahnani et al., 2021
Risk factors for retained placenta (RP) with considering the interaction terms were identified.
Considering of interaction terms in a risk factor analysis was informative.
Probability of RP differs between herd, age at first calving, parities, dry period length, milk yield level and calving season.
Twinning increased the risk of RP in multiparous cows but not in primiparus cows.
An experience of dystocia and stillbirth increased the risk of RP for both multiparous and primiparus cows
Changes in antioxidant enzyme activities and metabolic parameters in dairy cows during different reproductive periods
Sayiner et al., 2021
There is a significant relationship between the GPX enzyme activity and metabolic parameters in the postpartum period.
Could GPx’s significant rise in the early postpartum period be the messenger of metabolic diseases?
GPx and SOD are essential parameters as metabolic indicators in pre- and post partum period
Impact of assisted reproduction techniques on subsequent reproductive performance of dairy heifers and lactating cows
Figueiredo et al., 2020
Embryo donors had reduced hazard of first service and pregnancy linked to the time required for super stimulation protocols.
Ovum pick-up was associated with reduced pregnancy hazard in heifers and first lactation cows.
Fertility losses observed in Holstein donors were not associated with increased culling.
Evaluation of bovine sperm telomere length and association with semen quality
Ianuzzi et al., 2020
Sperm telomere length can be used as marker of bovine semen quality.
Sperm telomere length is correlated to most sperm quality traits.
Percoll density gradient separates sperm with longer telomeres
IFNT, ISGs, PPARs, RXRs and MUC1 in day 16 embryo and endometrium of repeat-breeder cows, with or without subclinical endometritis
Kasimanickam and Kasimanickam, 2020
ISGs, PPARs and RXRs were compared among normal and repeater breeder cows with or without subclinical endometritis.
ISG15, SLC2A1, CXCL10 and SLC27A6 were greater in endometrium of normal cows.
MUC1 was in greater in endometrium of repeat breeder cows with or without subclinical endometritis.
PPARD, PPARG, RXRA and RXRG were in greater in normal cows.
Gene network analysis showed interactions and pathways involving PPARD, PPARG, and MUC1.
Size and position of the reproductive tract impacts fertility outcomes and pregnancy losses in lactating dairy cows
Madureira et al., 2020
Lactating dairy cows with a larger reproductive tract have reduced P/AI and increased. Incidence of late embryonic mortality
Pregnancy associated glycoprotein concentrations on day 31 of gestation were reduced in. Cows with a larger reproductive tract
Larger reproductive tracts were more frequently observed in multiparous cows than primiparous cows
Cows with a larger reproductive tract were more likely to be culled from the herd
Chronological echocardiographic evaluation of left ventricular systolic and diastolic function in term and premature neonatal calves
Naseri et al., 2020
- Echocardiographic studies in human neonatology has demonstrated that prematurity can lead to cardiovascular dysfunction and especially compromises the left ventricular (LV) systolic and diastolic functions.
- There was LV diastolic dysfunction (55% premature calves, 10% term calf at day 1; 65% premature calves, 10% term calf at day 2 and, 75% premature calves, 20% term calf at day 3),
- LV systolic dysfunction deteriorated in both term and preterm calves (55% premature calves, 60% term calf at day 1; 55% premature calves, 50% term calf at day 2, and 45% premature calves, 40% term calf at day 3).
Echocardiography is a useful tool for evaluating cardiac functions and following heart development in neonatal animals
Influence of seasonal differences on semen quality and subsequent embryo development of Belgian Blue bulls
Sefi-Jamadi et al., 2020
Belgian Blue bulls are more susceptible to heat stress than most other cattle breeds.
Heat stress negatively affected the quality of Belgian Blue bulls’ spermatozoa.
Summer high ambient temperature increased H2O2 production in thawed spermatozoa.
Summer heat exposure increased morphological abnormalities of bull spermatozoa.
Embryo development was decreased after the bulls were exposed to summer heat stress
In summary, our data show that elevated ambient temperature and humidity during summer can decrease the quality of frozen-thawed spermatozoa in Belgian Blue bulls and also affect subsequent embryo developmen
Treatment with prostaglandin F-2 alpha and an intravaginal progesterone insert promotes follicular maturity in advance of gonadotropin-releasing hormone among postpartum beef cows
Bonacker et al., 2020
Treatments promoting follicular maturity prior to 7-d CO-Synch + CIDR were evaluated.
PGF2α and CIDR for 7 days increased follicle size and serum estradiol at GnRH.
CL status at final PGF2α and estrous response prior to FTAI tended to be improved
Effect of progesterone supplementation in a resynchronization protocol on follicular dynamics and pregnancy success
Epperson et al., 2020
The incorporation of a CIDR in a resynchronization protocol was not necessary to achieve adequate pregnancy rates.
Inclusion of a CIDR in a resynchronization protocol benefited heifers.
Early pregnancy detection on day 28 using a chute-side blood pregnancy test was found to be as reliable as ultrasonography.
Sensor technology to support herd health monitoring: Using rumination duration and activity measures as unspecific variables for the early detection of dairy cows with health deviations
Gusterer et al., 2020
Differences in activity and rumination data recorded by a accelerometer were observed between healthy and diseased cows.
*
Rumination times per day were shorter starting 5 days before clinical diagnosis in diseased cows compared with healthy cows.
’High active’ time started to be shorter 3 days before the clinical diagnosis in diseased cows.
Times cows spent ’inactive’ were significantly longer 3 days before the clinical diagnosis.
Lying time started to be longer 1 day before the clinical diagnosis of disorders in diseased cows
Differences in sperm functionality and intracellular metabolites in Norwegian Red bulls of contrasting fertility
Narud et al., 2020
Bulls of contrasting NR56 differed in sperm quality parameters and metabolome.
Metabolite analyses was performed on viable frozen-thawed sperm cells.
A model including DFI, aspartic acid, Fe and Zn explained variation in bulls’ NR56.
Antibacterial defense in bull and boar semen: A putative link to the microbiome and reproductive strategy?
Schulze et al., 2020
Sixty bull ejaculates were analyzed for bacterial killing activity and lysozyme.
Four-fifths of the samples had no ejaculate-associated defense against E. coli.
Lysozyme concentration in seminal plasma correlated with age of bull.
Lysozyme concentration in seminal plasma correlated with bull sperm quality.
Reproductive strategies & microbiome explain BKA differences between bull & boar ejaculate.
Comparison of behavioral patterns of dairy cows with natural estrus and induced ovulation detected by an ear-tag based accelerometer
Schweinzer et al., 2020
- Used an ear-tag based 3D-accelerometer system (SMARTBOW, Smartbow GmbH, Weibern, Austria) to generate data of behavioral patterns, i.e., rumination and activity.
- Part 1: behavioral patterns during the peri-estrus period were compared between cows with physiological estrus and cows subjected to an Ovsynch protocol.
▪ On the day before estrus and on the day of estrus/AI, cows with natural estrus showed a clear drop in rumination and inactivity and an increase in high activity, based on an algorithm of the accelerometer system, whereas, cows in the Ovsynch protocol showed only minor changes in behavioral patterns. - Part 2: analyzed behavioral patterns between synchronized cows that became pregnant after AI and synchronized cows that remained open.
▪ No differences were detected between these two Ovsynch groups before AI. - In this study we found no evidence that behavioral patterns can be used to improve conception rates within an Ovsynch protocol
Reproductive performance following a modified Presynch-Ovsynch, Double-Ovsynch, or conventional reproductive management program in Korean dairy herds
Kim et al., 2020
Modified Presynch-Ovsynch involved the administration of additional GnRH before Ovsynch.
Presynch-G-Ovsynch and Double-Ovsynch improved reproductive performance.
Presynch-G-Ovsynch yielded similar reproductive outcomes to Double-Ovsynch.
There were no marked differences in ovarian structure or progesterone concentration
Evaluation of an investigative model in dairy herds with high calf perinatal mortality rates in Switzerland
Mock et al., 2020 (Mee author)
See attached photo
*
The perinatal mortality (PM) rate in this study was 10% at the farm-level, and at the cow-level, 11.5%. These values, from high-risk farms, were approximately five-times higher than the contemporary national bovine PM rate (2.3%) in Switzerland.
The majority of calves died intrapartum. The most commonly diagnosed initiating/ultimate cause of death (UCOD) was infection of which Coxiella burnetii was the most frequently detected pathogen, by antigen.
The investigative model and research methods used in this study have external validity, which can be replicated and re-evaluated, respectively, in future studies on PM internationally
