Post Artificial Insemination Research Articles

Changes on corpus luteum structure and progesterone synthesis pathway after hCG or GnRH treatment during the early luteal phase in sheep

This study investigated the effect of hCG or GnRH on structural changes of the corpora lutea (CL) and the regulation of the expression of steroidogenic enzymes involved in P4 secretion in post-ovulatory (po-CL) and accessory CL (acc-CL). Sixty-four ewes were assigned to three groups receiving: 300 IU of hCG (hCG) or 4 µg Buserelin (GnRH) or 1 mL of saline solution (Control) on Day (d) 4 post artificial insemination (FTAI). Laparoscopic ovarian were performed on d 4, 14 and, 21 post-FTAI to determine the numbers of CL. Blood samples were collected for serum LH and P4 analysis. On d 14 post-FTAI, both CL were removed from the ovary to determine large luteal cell (LLC) number and to evaluate the expression of steroidogenic enzymes (HSD3B1, STAR, CYP11A1). Only hCG and GnRH treated ewes generated acc-CL. The LLC in both po- and acc-CL were significantly greater in the hCG group compared to GnRH and Control groups (P<0.05). Overall, hCG group showed the greatest immunodetection of HSD3B1and STAR in both po- and acc-CL (P<0.05). rnRNA expression of HSD3B1, STAR and CYP11A1 in the acc-CL tended to be greater in hCG group than in GnRH group (P<0.1). The LH concentration was increased in GnRH group (P<0.05) and P4 concentration was greater in hCG group compared to the other groups (P<0.05). In conclusion, administration of hCG has a notably impact on acc-CL development and the expression of steroidogenic enzymes compared to GnRH treatment in ewes. This leads to elevated P4 concentration and improved luteal function.

Oestrus induction and fertility response in post-partum anoestrus dairy cows treated with homeopathic medicine

The study was carried out to evaluate the effect of two homeopathic medicines to induce oestrus in 36 postpartum anoestrus crossbred Jersey dairy cows. Group 1 cows were fed a mineral mixture, and group 2 and 3 were medicated with Pulsatilla and Sepia drenched at the dose rate of 20 mL twice daily for 8 days, respectively. The mean plasma progesterone level (ng/mL) estimated using a radio immunoassay kit was significantly higher in group 2, followed by group 3 before and after medication on day 28 and 60, post artificial insemination (AI). Out of 12 induced for oestrus, 10 cows (83.33 %) and 9 cows (75.0 %) in group 2 and 3 were confirmed pregnant by rectal palpation on day 60 post AI, respectively. Both the homeopathic medicines showed 100% oestrus induction with a mean interval of 25.17 to 25.50 days, and Pulsatilla medicated cows showed improved fertility response than Sepia. The significantly higher level of progesterone after the withdrawal of homeopathic medication might be due to the release of circulating hormone, which blocks estradiol negative feedback. The subsequent increase reduces uterine PGF2 alpha secretion for a better conception rate.

IFNT stimulates lysosomal function via type I IFN signaling pathway in pregnant bovine leukocytes.

Interferon tau (IFNT) is important in establishing pregnancy in ruminants. Secreted IFNT in the uterus induces the expression of an interferon-stimulated gene (ISG) in uterine tissues and peripheral blood leukocytes (PBLs). In our previous study, increased lysosome and lysosomal cathepsin (CTS) activity and mRNA expression were observed in PBLs of pregnant cows on day 18 of pregnancy. However, the mechanism of IFNT stimulation in PBLs is unclear. Here, we explored the IFNT-mediated lysosomal activation mechanisms in PBLs during early pregnancy in dairy cows. PBLs collected from the peripheral blood of Holstein cows on day 18 post-artificial insemination (AI), after confirmation of their pregnancy status, were used to detect the expression of lysosomal-associated membrane protein (LAMP) 1, 2, CTSB and CTSK. Expression of all genes was significantly higher in PBLs of pregnant cows than in non-pregnant cows. In vitro IFN-mediated stimulation of PBLs collected from cows that did not undergo AI significantly increased lysosomal acidification and expression of LAMP1 and 2, as well as the activities of CTSB and CTSK. Immunodetection analysis showed an increase in LAMP1 and CTSK levels in the PBLs of day 18 pregnant cows. JAK inhibitor significantly decreased lysosomal acidification, CTSK activity, LAMP1, 2, and CTSK expression in the presence of IFNT. These results suggest that IFNT regulates lysosomal function via a type 1IFN-mediated pathway in PBLs during pregnancy recognition.

Circulatory extracellular vesicle derived miR-195-5p promotes cellular apoptosis and suppresses cell proliferation in the buffalo endometrial primary cell culture

In pregnant animals, communication between the mother and conceptus occurs via extracellular vesicles (EVs) that carry several biomolecules such as nucleic acids (miRNAs, mRNAs), proteins, and lipids. At the time of implantation, the endometrium undergoes several morphological and physiological changes, such as angiogenesis, apoptosis, and cell proliferation regulation at the implantation site, to attain a receptive state. This study was conducted to detect pregnancy-specific miRNAs derived from extracellular vesicles in the systemic circulation of Bubalus bubalis (water buffalo) and to assess their functional significance in the modulation of endometrial primary cells. The extracellular vesicles were isolated from the blood plasma using a precipitation-based method and further characterized by various methods such as Differential light scattering, Nanoparticle tracking assay, Western blot, and transmission electron microscopy. The relative expression of the selected extracellular vesicles associated miRNAs (EV-miRNA) at different intervals (days 15, 19, 25, and 30) post artificial insemination (AI) was analyzed using RT-qPCR, and expression of miR-195-5p was found to be significantly higher (P < 0.01) in pregnant animals on day 19 post AI (implantation window) as compared to day 15 post AI. The elevated expression might indicate the involvement of this miRNA in the maternal-conceptus cross-talk occurring during the implantation period. The KEGG pathway enrichment and Gene Ontology analyses of the miR-195-5p target genes revealed that these were mostly involved in the PI3-Akt, MAPK, cell cycle, ubiquitin-mediated proteolysis, and mTOR signaling pathways, which are related to the regulation of cell proliferation. Transfecting the in vitro cultured cells with miR-195-5p mimic significantly suppressed (P < 0.05) the expression of its target genes such as YWHAQ, CDC27, AKT-3, FGF-7, MAPK8, SGK1, VEGFA, CACAND1, CUL2, MKNK1, and CACAN2D1. Furthermore, the downregulation of the miR-195-5p target genes was positively correlated with a significant increase in the apoptotic rate and a decrease in the proliferation. In conclusion, the current findings provide vital information on the presence of EV miR-195-5p in maternal circulation during the implantation window indicating its important role in the modulation of buffalo endometrium epithelial cells via promoting cell death. Altogether, the milieu of miR-195-5p may serve as a novel and potential molecular factor facilitating the implantation of the early embryo during the establishment of pregnancy in buffaloes. Thus, miR-195-5p may be identified as a unique circulatory EV biomarker related to establishing pregnancy in buffaloes as early as day 19 post-AI.

Association of transition cow health with pregnancy per artificial insemination and pregnancy loss in Holstein cows submitted to a Double-Ovsynch protocol for first service

This observational study was conducted to evaluate the effect of transition cow health on pregnancy per artificial insemination (P/AI) and pregnancy loss (PL) in cows submitted to a Double-Ovsynch protocol (DO) for first service. Lactating Holstein cows (n = 15,041) from one commercial dairy farm in northern Germany between January 2015 to December 2021 were enrolled into a modified Double-Ovsynch protocol (GnRH, 7 d later PGF2α, 3 d later GnRH, 7 d later GnRH, 7 d later PGF2α, 24 h later PGF2α, 32 h later GnRH, and 16 to 18 h later timed artificial insemination) for first service at 72 ± 3 d in milk. Pregnancy was diagnosed at 32 and 60 d post-AI via transrectal ultrasonography. Pregnancy loss was defined as the proportion of cows diagnosed pregnant 32 d post-artificial insemination that were diagnosed nonpregnant 60 d post-artificial insemination. Health-related events (i.e., milk fever [MF], hyperketonemia [KET], retained fetal membranes [RFM], metritis, mastitis, left displaced abomasum [LDA]) were assessed by farm personnel using standard operating procedures. Multivariable logistic regression was used for testing potential associations between transition cow health event occurrence and outcome variables, including P/AI and PL. Three separate models were built for cows in first lactation, second lactation, and ≥third lactation. Overall, 20.0% (885/4,430), 34.9% (1,391/3,989), and 53.9% (3,570/6,622) of cows had at least one transition cow health event for first, second, and ≥third lactations, respectively. The most prevalent transition cow health event for first-lactation cows was metritis (10.7%; [473/4,430]), whereas second-lactation cows suffered mostly from mastitis (16.6%; [664/3,989] and KET (16.6%; [661/3,989]), and cows with ≥third lactations were mostly affected by KET (33.2%; [2,198/6,622]). We observed a negative association between inflammatory disorders (i.e., RFM, metritis, mastitis) and P/AI in all cows irrespective of parity. Metabolic disorders (i.e., MF, KET, LDA) were negatively associated with P/AI only in multiparous cows. Irrespective of parity, only uterine diseases (i.e., RFM, metritis) were significantly associated with PL. These results show that enrolling cows into a fertility protocol, such as DO, cannot overcome the carryover effects of inflammatory and metabolic disorders on P/AI and PL and highlight the importance of optimizing transition cow health as a prerequisite for achieving high fertility in a DO protocol.

The effect of progesterone concentrations during superovulation of Holstein heifers in a randomized trial

The aim of this study was to evaluate the effect of different progesterone (P4) concentrations during the follicular growth on the intensity of estrous expression, ovarian response to the superovulatory treatment, and embryo production and quality in superovulated heifers. A total of 63 Holstein heifers were randomly assigned into 2 experimental groups: Low P4 (n = 31) and High P4 (n = 32). Animals received a pre-synchronization protocol followed by a protocol of superovulation that included the allocated P4 treatment. Activity was monitored continuously by an automated activity monitor, and estrus characteristics (maximum intensity and duration) were recorded. Embryo collection was performed 7 d post artificial insemination (AI). Embryos were counted and graded from good or excellent (1) to degenerated (4). The outcomes of interest were: number and diameter of follicles at the time of AI, ovulation success (confirmed 7 d post-AI), time to estrus event, maximum intensity and duration of estrus, number and quality of embryos. Data were analyzed according to the type of outcome variable using logistic, linear, or Poisson regression models. A total of 105 embryos (High P4: n = 42; Low P4: n = 63) were graded for quality. Different P4 levels did not affect the maximum intensity (High P4 = 497.8 ± 23.9%; Low P4 = 542.2 ± 23.5%) or the duration (High P4 = 13.5 ± 1.5 h; Low P4 = 14.3 ± 1.4 h) of estrus. Heifers in the High P4 treatment had greater number of follicles at time of AI (High P4 = 16.6 ± 1.6 follicles; Low P4 = 13.9 ± 1.2 follicles), but with smaller diameter (High P4 = 11.3 ± 0.1 mm; Low P4 = 12.0 ± 0.1 mm) compared with Low P4. High P4 heifers tended to have better embryo quality compared with Low P4 heifers (odds ratio = 1.98; 95% CI = 0.90-4.35). High P4 heifers had less embryos than Low P4 heifers, but this was modified by the CIDR (intravaginal implant of P4) removal to estrus interval (interval 0-21 h: mean ratio = 1.15, 95% CI = 0.42-1.87; interval 22-46 h: mean ratio = 0.58, 95% CI = 0.27-0.96). Although estrous expression was not associated with embryo quality, as the duration and the maximum intensity of estrous expression increased, the number of embryos recovered 7 d post-AI increased (duration: mean ratio = 1.04; 95% CI = 1.03-1.05; maximum intensity: mean ratio = 1.50; 95% CI = 1.42-1.58). In conclusion, P4 during the follicular growth, and intensity of estrus, are playing a role in regulating the quality and the number of embryos produced by superovulated heifers. This study was supported by contributions from Resilient Dairy Genome Project and the Natural Sciences and Engineering Research Council.

Evaluation of Alfaglandin C and associated factors on efficiency of cows’ estrus synchronization and artificial insemination in North Shoa Oromia, Ethiopia

Synchronization of estrus involves handling the estrus cycle so that a large number of cows can be bred at approximately the same time. Proper cow/heifer selection as well as efficient coordination are all key elements for the success of synchronization programs which were lacking in the study area. The study was conducted with the objective to evaluate the effect of Alfaglandin C and fixed factors on estrus synchronization and efficiency of Artificial Insemination (AI) in North Shoa zone of the Oromia region. The study population encompassed indigenous and crossbred cows and heifers found in six purposively selected kebeles (smallest administrative unit within a district) from the three selected districts (Wucale, Dagam and Kuyuu). Multistage sampling procedure was used to select target districts, kebeles and experimental cows/heifers. A total of 180 cows and heifers fulfilling estrus synchronization criteria were selected purposively and injected with synchronizing hormone (Alfaglandin C). The level of significance among categorical variables was determined using the chi-square (x2) test. About 70.6% of the cows and heifers injected with Alfaglandin C exhibited estrus. Exhibition of estrus following hormone injection was significantly (p&lt;0.05) lower in Wuchale district compared with that of the other two districts. Likewise, the agroecology, farming system, herd group, and breed had a significant (p&lt;0.05) effect on estrus exhibition. Among cows and heifers inseminated following estrus exhibition, 62.2% conceived as confirmed by pregnancy diagnosis (PD) test conducted at 45-day post AI, which dropped to 58.3% as observed by the PD test conducted three months’ post AI. Agroecology, farming system, herd group, and genotype of cows and heifers showed significant (p&lt;0.05) influence on the conception rate (CR). The highest CR was observed among cows of Kuyuu district, which was significantly (p&lt;0.05) different from that of the other two districts. The overall calving rate was 91.1%. The semi-intensive part of the study also showed better estrus synchronization response and better reproductive performances which directly associated with the management practices. Treating industrial byproducts, better management, and promoting AI can achieve better estrus synchronization and efficiency of artificial insemination. Key words: alfaglandin C, calving rate, conception rate, district, estrus exhibition, pregnancy diagnosis

Temporal analysis of circulating nucleic acid in early days of pregnancy in buffalo.

Improving reproductive efficiency in livestock relies mainly on the ability to detect pregnancy quickly and accurately. Recently, circulating nucleic acids (CNAs) have been exploited for prenatal diagnosis in humans and animals. In the current investigation, serum samples were collected from pregnant animals (n = 30) and non-pregnant animals (n = 20) on 0th, 6th, 12th, and 18th day post artificial insemination. Total DNA was isolated from these serum samples. Two CNA tags (Bov-B and ART2A) derived from repetitive sections of the bovine genome were amplified using DNA extracted from serum samples. The expression analysis of these CNAs was done using real-time polymerase chain reaction assay, and copy number of each tag was calculated in pregnant and non-pregnant animals. The average number of copies of Art2A increased approximately threefold (P < 0.01) from day zero of pregnancy (7,000 copies) to the day 18 of pregnancy (> 21,000). Similarly, BovB levels in the pregnant group increased significantly (approximately 2.9-fold) from day zero (93,900 copies) till day 18 (> 2, 72,310 copies) (P < 0.01). There was no significant change observed on the 6th and 12th day of pregnancy and on the 18th day in the non-pregnant animals. In conclusion, based on these findings, the defined cut-off value can distinguish between pregnant and non-pregnant animals with a sensitivity of nearly80% and specificity of nearly70%. It is possible to employ these two CNA tags as biomarkers for early detection of pregnancy in buffaloes.

Review: Initial increase in pregnancy-specific protein B in maternal circulation after artificial insemination is a key indicator of embryonic survival in dairy cows.

Lactating dairy cows have reduced chances for pregnancy survival following 1st parturition. It appears that timing of conceptus attachment, defined as an initial daily rise in pregnancy-specific protein B (PSPB) postartificial insemination (AI), is key to the survival of the embryo. PSPB is a protein produced from binucleate cells of the trophectoderm of the conceptus. Once the conceptus has attached to the uterine epithelial cells, this large protein is detectable in maternal circulation. Daily sampling of serum allows for detection of the initial increase of PSPB. A percent increase threshold for PSPB was determined from results from each study using a conservative three-day minimum increase. Thus far, a 10 or 12.5% daily increase for three consecutive days had the greatest sensitivities and specificities for studies reported in this review. Nulliparous heifers receiving AI following estrus appear to have a reduced time to conceptus attachment compared to lactating cows that received either Ovsynch or AI following estrus. Increasing progesterone post-AI did not reduce time to conceptus attachment in lactating cows. Multiparous cows treated post-AI with human chorionic gonadotropin had a reduced percent with conceptus attachment in addition to greater time to conceptus attachment. Increased time to conceptus attachment increased the chances of multiparous cows having embryonic death before 35 d post-AI. Concentrations of PSPB are consistently reduced from conceptus attachment until d 28 post-AI in cows with pregnancy loss compared to cows that maintain pregnancy on d 34 post-AI. This novel model to determine timing of conceptus attachment provides a new perspective on percent of cows pregnant around d 20-23 post-AI and the potential for a greater understanding of subsequent pregnancy loss.

Efek Tipe Kelahiran Terhadap Estrus Post-Partum Induk Sapi Bali Akseptor Inseminasi Buatan

Cases of dystocia is impact on delaying uterine involution, post-partum estrus and the next mating. Research has been carried out about type of birth process and its effect on post-partum estrus post-artificial insemination (AI) of Bali cows in Pujut District, Central Lombok Regency. The aim was to determine the effect of the type of birth process on post-partum estrus of cows. The research used descriptive method with the material were 40 Bali cows in 4 (four) villages, namely Pengengat, Teruwai, Mertak and Bangket Parak. The research variables were the type of birth process and post-partum estrus, as well as supporting variables such as the age of cow, body condition score (BCS), body weight, type of bull semen and days open. The data were statistically analyzed including the mean, standard deviation and percentage, followed by t-test. The results showed that 52.25% of Bali cows in Pujut District gave birth normally and 47.5% suffer light dystocia with birth assistance. The mean age of cows with dystocia was 29.53 ± 5.72 months by the BCS of 2.53, compared to 31.62 ± 5.61 months by the BCS of 2.81 in normal birth. The mean weight was 319.00 ± 29.72 kg compared to 342.81 ± 49.36 kg. The mean days open was 199.13 days compared to 195.67 days and post-partum estrus was 122.00 days compared to 105.00 days. In conclusion, the onset of post-partum estrus and days open in Bali cows that suffer light dystocia with birth assistance is longer than normal birth.

The Role of Transrectal Sonography in Pregnancy Diagnosis in Cattle

Objective: A reproduction management strategy is an essential component of any cattle production operation. Options include palpation per rectum, transrectal sonography, or biochemical blood tests. To determine the best method, veterinary costs must be weighed against operational costs of maintaining open cattle. Materials and Methods: An online literature search using PubMed, Medline, CINAHL, EBSCO, and Google Scholar was completed to find relevant articles regarding pregnancy detection in cattle, costs of reproductive management in cattle, and pregnancy loss in cattle. Priority was given to original research articles pertaining to palpation per rectum, transrectal ultrasound, fetal gender, and pregnancy loss. Results: Transrectal sonography can detect a pregnancy up to 15 days earlier than palpation per rectum and has sensitivities and specificities as high as 97% when performed between days 21 and 35 post artificial insemination. Conclusion: Cattle producers can be confident that transrectal sonography is a useful tool in the beef and dairy cattle industry. Its use facilitates reproductive management decisions, such as re-breeding or culling, thus reducing expenses, and increasing profitability.

Association between body condition score fluctuations and pregnancy loss in Holstein cows.

The objective of this study was to characterize the associations between body condition score (BCS) and BCS change (∆BCS), determined by an automated camera system during early lactation and close to artificial insemination (AI), and the subsequent pregnancy loss (PL) in Holstein cows. A secondary objective was to determine the impact of disease on PL, considering multiple time periods relative to AI. Data from 9,430 lactations in 6,884 Holstein cows in a commercial dairy operation located in Colorado, USA were included in this retrospective observational study. Cows were subject to first AI at about 80 DIM (primiparous) and 60 DIM (multiparous), following a double OvSynch protocol. Pregnancy diagnosis was performed via transrectal ultrasonography on day 32 ± 3 after AI and reconfirmed on day 80 ± 3 after AI. Cameras mounted on the sorting gate at each exit (n = 2) of the milking parlor generated BCS on a five-point scale with 0.1 increments. The BCS at calving (BCS1), 21 DIM (BCS21), 56 DIM (BCS56), AI resulting in pregnancy (BCSAI), and 90 d post AI (BCSAI90) were selected for the analyses and subsequently categorized as low (≤ lower quartile), moderate (interquartile range), and high (≥ upper quartile). Changes in BCS were calculated by periods of interest as change from calving to 21 DIM; change from calving to 56 DIM; change from 56 DIM to AI; and change from AI to 90 d post AI and assigned into categories to facilitate the analysis. Data were examined using logistic regression, considering parity category, season at calving and AI, DIM at AI, milk yield up to 60 DIM, and occurrence of disease as covariables. The logistic regression analyses indicated that the odds of PL were greater in cows in the low BCS category relative to cows in the high BCS category at 56 DIM (OR 95% CI = 1.41 [1.12-1.79]), AI (1.31 [1.05-1.65]), and 90 d post AI (1.38 [1.10-1.74]). Likewise, cows with large loss in BCS between calving and 21 DIM (1.46 [1.10-1.94]) and loss in BCS between AI and 90 d post AI (1.44 [1.15-1.81]) had greater odds of PL compared with cows with no loss of BCS within the same period. Occurrence of disease at all the time periods considered in the analysis had a consistent detrimental impact on maintenance of the pregnancy, supporting the concept that pre and postconceptional disease affects embryonic survival. Overall, low BCS, more pronounced reductions in BCS occurring closer to AI, and occurrence of disease resulted in greater PL in this Holstein population.

Clinical Overview of Luteal Deficiency in Dairy Cattle

Simple SummaryLuteal deficiency is defined as reduced progesterone production by the corpus luteum, either in the amount or duration, or both. The clinical manifestations include primary infertility and pregnancy loss during the late embryonic/early fetal period (30–50 days post-AI). This work provides a clinical overview of the current understanding of luteal deficiency and its association with low fertility in dairy cows.Luteal deficiency is defined as reduced progesterone (P4) steroidogenesis by the corpus luteum (CL), either in the amount or duration, or both. This work provides a clinical overview of the current understanding of luteal deficiency and its association with low fertility in dairy cows. Low plasma P4 concentrations during the luteal phase post-artificial insemination (AI) are associated with lower conception rates. Treatments post-AI with P4, gonadotropin-releasing hormone (GnRH) or human chorionic gonadotropin (hCG) improve fertility in some conditions. Sub-luteal function during the late embryonic period (at pregnancy diagnosis, i.e., 28–34 days post-AI), is just one factor among other factors associated with pregnancy loss. Treatment with P4 in cows with one CL favors pregnancy maintenance, while GnRH treatment does the same in cows carrying twins. The diagnosis of sub-luteal function can be made clinically on the basis of plasma or milk P4 concentrations. Automated in-line milk P4 analysis systems to diagnose luteal activity emerge as a very interesting tool in dairy herds. Monitoring plasma or milk P4 concentrations with the help of Doppler ultrasonography to assess the CL function would allow individualizing the luteal phase support.

Effect of Breed and Risk Factors Affecting Conception Rate to Artificial Insemination in Dairy Cows of Tullo District Western Haraghe, Ethiopia

Aim This study was conducted using the questionnaire method to assess the effect of breed and factors affecting conception rate on artificial insemination in dairy cows in Tullo district, Western Haraghe, Ethiopia. Methods A follow-up study design was conducted from December 2018 to June 2019 to determine the effect of breed and factors affecting conception rate to artificial insemination in dairy cows, taking breed, age, parity, body condition and timing of insemination as risk factors. The demographic factors were recorded by interviewing the owners. Most of the cows were examined for pregnancy diagnosis by rectal palpation of the genital tract at 60-80-days post-artificial insemination. Results Out of 114 artificially inseminated cows/heifers, 59 became pregnant, giving an overall first service conception rate of 51.8%. Although the breed, age, parity and body condition score did not affect the conception rate significantly, the pregnancy rate was better in the cross-breed (62.5%), in cows of 5-7-years of age (54.6%), in cows of parity 2-3 (59.2%) and in cows of good body condition score (57.7%). The conception rate in cows inseminated at 12-18-hours after the onset of estrus was significantly higher (62.3%) than those inseminated after 18-hours (31.2%) and before 12-hours (52.4%) after the onset of estrus. Therefore, cows with good body condition score (BCS) and artificial insemination (AI) service at 12-18-hours after the onset of estrus are the best choice of selection for obtaining the best result in the first service conception rate to AI in dairy cows/heifers. Conclusion This study reveals that the conception rate was influenced by the time of AI, so awareness should be given to cattle owners, as they should give AI for their cattle at optimum time within 12-18-hours after onset of heat sign.

The effects of light colour on female rabbit reproductive performance and the expression of key genes in follicular development.

The purpose of this study was to analyse the effects of light colour on rabbit reproductive performance and the expression of key follicular development genes. Rabbits (n = 1,068, 5 months old, 3.6–4.4 kg live body weight) were divided randomly into four groups, housed individually in wire mesh cages and exposed to red, green, blue, and white light-emitting diode (LED) light (control). The lighting schedule was 16 L : 8 D-15 d / 150 lx / 6:00 am–22:00 pm (3 d preartificial insemination to 12 d postartificial insemination). Red light and white light affected the conception rate and kindling rate and increased the total litter size at birth (p < 0.05). The effects of red light on litter size at weaning, litter weight at weaning, and individual weight at weaning increased compared with the green and blue groups. The effects of red light on live litter size at birth were increased compared with those in the blue group (p < 0.05). Compared to white light, green and blue light reduced the number of secondary follicles (p < 0.05). Compared to red light, green and blue light reduced the number of tertiary follicles (p < 0.05). Compared with white light, red LED light resulted in greater ovarian follicle stimulating hormone receptor and luteinizing hormone receptor mRNA expression (p < 0.05). Compared with green and blue LED light, red LED light resulted in greater B-cell lymphom-2 mRNA expression (p < 0.05). Compared with green LED light, red LED light inhibited FOXO1 mRNA expression in rabbit ovaries (p < 0.05). Red light can affect the reproductive performance of female rabbits and the expression of key genes for follicular development.

Early pregnancy diagnosis based on luteal morphology and blood flow on Days 17–21 post-artificial insemination in Japanese Black cattle

The present study was conducted to evaluate the applicability of corpus luteum (CL) morphology and blood flow for early pregnancy diagnosis on Days 17–21 post-artificial insemination (AI) in Japanese Black (JB) cattle. Ultrasound examinations were performed on 230 inseminated JB cattle (202 cows and 28 heifers) to evaluate CL morphological characteristics [CL area, CL tissue area, presence/absence of a central cavity, and central cavity area (CCA)] and blood flow area (BFA) on Days 17 (n = 46), 18 (n = 45), 19 (n = 46), 20 (n = 47), and 21 (n = 46) (Day 0 = the day of AI). Pregnancy was confirmed using brightness-mode ultrasonography on Day 30. In pregnant group (n = 141), CL area and CL tissue area were greater (P < 0.001) than those in non-pregnant group (n = 89) on and after Day 19. Moreover, BFA was greater (P < 0.05) in pregnant group on and after Day 18. The overall central cavity incidence was lower (P < 0.001) and CCA was smaller (P < 0.001) in pregnant group. Logistic regression analyses revealed that the best single predictor for pregnancy diagnosis was BFA on Days 17–20 (sensitivity = 69%–100% and specificity = 65%–91%). On Day 21, CL area or CL tissue area was the most accurate predictor (cutoff value = 267.78 mm2, sensitivity = 100%, and specificity = 100%). The best set of predictors for pregnancy diagnosis was specified as the BFA and [CCA × BFA] pair. Setting BFA cutoff value in the cattle without central cavity at 55.26 mm2 yielded the highest sensitivity (97%) and specificity (88%) on Days 18–20. The accuracy of pregnancy diagnosis using BFA or BFA and [CCA × BFA] pair on Day 17 was lower than those on and after Day 18. In conclusion, BFA and CCA are effective for early pregnancy diagnosis on Days 18–20 post-AI in JB cattle; however, it is inadequate on Day 17 owing to its low accuracy. Evaluating CL area or CL tissue area on Day 21 is the most accurate method of pregnancy diagnosis.

Effects of feed restriction during pregnancy on maternal reproductive outcome, foetal hepatic IGF gene expression and offspring performance in the rabbit

Primiparous female rabbits have high nutritional requirements and, while it is recommended that they are subjected to an extensive reproductive rhythm, this could lead to overweight, affecting reproductive outcomes. We hypothesised that restricting food intake during the less energetic period of gestation could improve reproductive outcome without impairing offspring viability. This study compares two groups of primiparous rabbit does in an extensive reproductive programme, one in which feed was restricted from Day 0 to Day 21 of gestation (R021), and another in which does were fed ad libitum (control) throughout pregnancy. The mother and offspring variables compared were (1) mother reproductive outcomes at the time points pre-implantation (Day 3 postartificial insemination [AI]), preterm (Day 28 post-AI) and birth; and (2) the prenatal offspring characteristic IGF system gene expression in foetal liver, liver fibrosis and foetus sex ratio, and postnatal factor viability and growth at birth, and survival and growth until weaning. Feed restriction did not affect the conception rate, embryo survival, or the number of morulae and blastocysts recovered at Day 3 post-AI. Preterm placenta size and efficiency were similar in the two groups. However, both implantation rate (P < 0.001) and the number of foetuses (P = 0.05) were higher in the R021 mothers than controls, while there was no difference in foetal viability. Foetal size and weight, the weights of most organs, organ weight/BW ratios and sex ratio were unaffected by feed restriction; these variables were only affected by uterine position (P < 0.05). Conversely, in the R021 does, foetal liver IGBP1 and IGF2 gene expression were dysregulated despite no liver fibrosis and a normal liver structure. No effects of restricted feed intake were produced on maternal fertility, prolificacy, or offspring birth weight, but control females weaned more kits. Litter weight and mortality rate during the lactation period were also unaffected. In conclusion, pre-implantation events and foetal development were unaffected by feed restriction. While some genes of the foetal hepatic IGF system were dysregulated during pregnancy, liver morphology appeared normal, and the growth of foetuses and kits until weaning was unmodified. This strategy of feed restriction in extensive reproductive rhythms seems to have no significant adverse effects on dam reproductive outcome or offspring growth and viability until weaning.

Adoption of scientifically recommended artificial insemination practices by paravets: a depiction of current scenario of four states in India.

The present investigation was done to assess the different practices followed by the AI technicians (paravets) while performing artificial insemination (AI). A total of 160 paravets were selected for the study having equal representation from 4 different states of India (Gujarat, Rajasthan, Telangana, and Odisha). Questionnaire and telephonic survey were used for collecting data. Several practices followed by paravets were assessed under three sub-groups, viz., practices followed prior to, during, and post-artificial insemination. In as many as seven practices, viz., gathering pre-AI information, storage of semen straw, time of performing AI, thawing container, wiping of semen straw, cutting of semen straw, and record keeping, the adoption gap was found to be nil. Maximum adoption gap (30.60%) was seen in "adopting basic sanitary measures," whereas about 13% of adoption gap was found in the case of "monitoring of heat post calving" followed by "checking of heat prior to AI" (8.00%). Hence, along with provision of necessary measures for water bath, apron, and gumboots by State Department of Animal Husbandry (SDAH), the paravets should be made aware about the importance of basic sanitary measures. Crystoscope availability should also be ensured as it is easy to use by paravets and farmers for heat detection.

Expression profiling of chemokines CCL8 and CXCL10 during peri-implantation period in Murrah buffaloes as a possible signature of embryonic implantation

The present investigation was aimed to evaluate novel implication of chemokine genes CXCL10 (C-X-C motif chemokine 10) and CCL 8 (C-C motif chemokine 8) genes for use as ideal pregnancy biomarker in dairy buffaloes. We studied expression profile of both these chemokine genes in whole blood of Murrah buffaloes on day 12, 15, 18 and 21 post artificial insemination (AI) using SYBR green chemistry based quantitative real time reverse transcription PCR. Our investigations revealed a consistent increase in transcriptional abundance of CCL8 and CXCL10 genes during this period, although the difference in expression level was not significant between day 15 and 18 post AI for CXCL10 gene. We also studied the effect of parity on the expression profile of these two genes and found that expression level of both these genes is independent of parity status of the animal. Based on the results, it can be concluded that these chemokine genes can be used as early pregnancy biomarker on any day between days 12 to 21 post artificial insemination in buffaloes irrespective of their parity status.

Influence of Different Regimes of Moderate Maternal Feed Restriction during Pregnancy of Primiparous Rabbit Does on Long-Term Metabolic Energy Homeostasis, Productive Performance and Welfare.

Simple SummaryIn rabbit farms, the main production costs come directly from food supplies. Although the reproductive outcomes in this species are acceptable, the results are worse when it comes to primiparous rabbits, so it is recommended that insemination be carried out post-weaning. By avoiding the overlap of the second gestation and the first lactation, better fertility results are expected. Still, despite this, the rabbits garner more adipose tissue than desired, and the productive efficiency deteriorates in the long term. The purpose of this study was to evaluate the influence of different periods of moderate feed restriction (one, two or three weeks) applied during the second pregnancy of primiparous does. We studied fetoplacental development, productive parameters, metabolism and possible stress indicators. Results showed that the voluntary feed intake of dams increased right after feed restriction. No permanent alterations were found in reproductive outcome, metabolism or welfare of does, meaning that this feeding strategy could be successfully applied in rabbit farms.In this study, a maternal feed restriction (MFR; 105 g/d) in primiparous rabbit does was applied from day 0 to 7 post artificial insemination (AI) (R07, n = 96), from day 7 to 21 post AI (R721, n = 92), from day 0 to 21 post AI (R021, n = 94) or fed ad libitum during whole pregnancy (Control, n= 92). Feed intake (FI) was measured after MFR was over. On day 28 of gestation, fetoplacental development was evaluated (n = 11/group) and the productive parameters of the remaining dams were analyzed. Plasma free tri-iodothyronine (T3) and thyroxine, glucose, insulin, non-esterified fatty acids (NEFA), and corticosterone were analyzed during gestation and lactation (n = 5/group). After MFR, all groups significantly increased their voluntary FI. The longer MFR was, the lower the weight and length of the fetuses, but no long-term effects over litter performance were observed. R021 groups had the lowest T3 and the highest NEFA concentrations during pregnancy and showed insulin resistance at the end of gestation, but during lactation, energy homeostasis was balanced in all groups. MFR did not affect corticosterone concentrations. In conclusion, the ration setting applied slightly involved the energy homeostasis and metabolism of the animals, but their overall metabolic condition, productive performance and welfare were not compromised.