Theriogenology最新文献

{"title":"The use of the serum progesterone strip test as a clinical tool for assessing reproductive status in replacement gilts.","authors":"Preechaphon Taechamaeteekul, Umaporn Pimpitak, Junpen Suwimonteerabutr, Wanwisa Poonlapdecha, Nutthiwut Khun-Arwut, Kittinan Komolpis, Sirirat Rengpipat, Kridtasak Sang-Gassanee, Hongyao Lin, Miquel Collell, Robert V Knox, Padet Tummaruk","doi":"10.1016/j.theriogenology.2025.117627","DOIUrl":"10.1016/j.theriogenology.2025.117627","url":null,"abstract":"<p><p>Identifying the reproductive status of replacement gilts at the appropriate age can improve mating efficiency and reduce non-productive days. This study aimed to evaluate the reproductive status of gilts and assess the accuracy of a serum progesterone strip test. A total of 112 Landrace × Yorkshire gilts, aged 196-238 days, were enrolled. Estrus detection was performed daily from 189 days of age using the back-pressure test with fence-line boar exposure. Blood samples were collected from all gilts, and serum progesterone levels were determined using both ELISA and a progesterone lateral flow assays (LFAs) strip test. Puberty was defined by an ELISA-based serum progesterone concentration ≥5.0 ng/ml. The LFAs employed a competitive assay using a monoclonal antibody against progesterone. A single test line indicated a 'positive' result (pubertal), while two lines indicated 'negative' (prepubertal). To perform the test, 2-3 drops of serum were applied to the strip, with results read after 15 min. Based on ELISA, 51.8 % of gilts were pubertal and 48.2 % were prepubertal. Pubertal gilts had significantly higher serum progesterone levels than prepubertal gilts (30.8 ± 11.4 vs. 0.8 ± 0.8 ng/ml; P < 0.001). The LFAs correctly identified 98.2 % of pubertal gilts and 94.4 % of prepubertal gilts, yielding a sensitivity of 98.2 % and specificity of 94.4 %. In conclusion, the progesterone strip test demonstrated high accuracy and shows strong potential for on-farm use in identifying pubertal gilts based on serum progesterone concentration.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"248 ","pages":"117627"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144804913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evidence of ineffectiveness of insulin-like growth factor 1 (IGF-1) on in vitro production of bovine embryos: systematic review and meta-analysis.","authors":"Giovana de Santi Phelippe Nunes, Alan Brunholi Giroto, Sarah Gomes Nunes, Edson Assunção Mareco, Beatriz Díaz-Fabregat, Anthony César de Souza Castilho","doi":"10.1016/j.theriogenology.2025.117626","DOIUrl":"10.1016/j.theriogenology.2025.117626","url":null,"abstract":"<p><p>Unsatisfactory results of in vitro maturation (IVM) impair the development, survival and implantation of the embryo. Insulin-like growth factor 1 (IGF-1) is widely used in IVM, but its efficacy is controversial and consistent evidence is lacking. To investigate the efficacy of IGF-1 in IVM, we conducted a systematic review and meta-analysis on bovine oocytes competence and subsequent embryonic development. We structured the research question according to the PICO model: \"Does IGF-1 enhance in vitro embryo production in cattle during maturation?\" We consulted scientific databases such as PubMed/MEDLINE, Embase and Scopus. The assessment of the methodological quality of the selected articles, the risk of bias, was performed with SYRCLE® by two reviewers. Data analysis was performed with R software, the \"META\" package for meta-analysis, using the metabin function to assess data proportions and estimate random effects, and the forest function for graphical representation. Of the 43 articles evaluated, eight were included in the statistical analysis. The results of the meta-analysis showed no significant effect of IGF-1 on cleavage rate (OR = 1.28 [0.96; 1.71]; p > 0.05) and on blastocyst yield (OR = 0.88 [0.64; 1.22]; p > 0.05). In conclusion, although IGF-1 is a key protein for cell differentiation, its addition during IVM does not promote blastocyst development. Therefore, we propose novel strategies to increase the bioavailability of IGF-1 during IVM in cattle to potentially improve embryonic outcomes.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"248 ","pages":"117626"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144817467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of e-learning training on technical performance for bovine sperm morphology analysis in a multi-laboratory setting.","authors":"Leonardo F C Brito, Clara González-Marín, Pablo J Ross","doi":"10.1016/j.theriogenology.2025.117687","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2025.117687","url":null,"abstract":"<p><p>Although sperm morphology analysis is a fundamental component of bovine semen evaluation, substantial variations in results within and across laboratories have been reported. The objective of the present study was to evaluate the effect of e-learning training to standardize morphology analysis in a multi-laboratory setting. In Experiment I, the performance of 40 technicians from 10 laboratories was evaluated using digital sperm images. Assessment score improved (P < 0.05) shortly after training (85.1 ± 1.3 %; mean ± SEM) when compared to pre-training baseline (78.3 ± 1.8 %) but was not significantly different from baseline eight months after training (83.8 ± 1.7 %). In Experiment II, the performance of eight technicians from six laboratories was evaluated using reference frozen-thawed semen samples. Overall intra-technician CV for normal sperm, and primary and secondary defects were 4.0 ± 4.3 %, 22.9 ± 25.2 %, and 16.8 ± 16.0 %, whereas intra-batch CV were 6.2 ± 4.4 %, 33.7 ± 19.8 %, and 24.0 ± 12.4 %, respectively. The intra-technician CV for normal sperm decreased shortly after training when compared to pre-training baseline and remained low six months after training. The intra-batch CV for normal sperm decreased shortly after training but was not significantly different from baseline six months after training. When Bland-Altman plots were evaluated, the mean difference of individual results from the overall mean was close to zero (-2.1 to 1 %) for all morphology classification categories during all test periods. In conclusion, e-learning training improved technician performance for bull sperm morphology analysis. Precise and accurate results for normal sperm morphology can be obtained with the use of standardized procedures when performed by trained and experienced technicians, but biannual re-training and assessment might be required to maintain optimal technical performance. In addition, simple sperm morphology classification systems (normal vs. abnormal) may be more robust than complex defect categorizations for quality control in semen processing centers.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"250 ","pages":"117687"},"PeriodicalIF":2.5,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145207624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"13-cis-retinoic acid modulates porcine ovarian granulosa cell differentiation via retinoic acid signaling-FoxA1 axis: Implications for ovarian follicular development and luteinization.","authors":"Hong-Liang Zhang, Hua-Biao Wang, Yi-Xuan Mi, Xia-Meng Wu, Li Bao, Ming Zhao, Li Ma, Shui-Lian Wang","doi":"10.1016/j.theriogenology.2025.117682","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2025.117682","url":null,"abstract":"<p><p>13-cis-Retinoic acid (13cRA), a vitamin A derivative clinically employed in cancer therapy, demonstrates novel regulatory effects on ovarian follicular development and luteinization through granulosa cell proliferation and differentiation in this study. Our murine model revealed that 13cRA administration significantly increased the number of primary follicle and corpus luteum by ovarian sectioning and follicle counting, indicating accelerated follicular maturation and ovulation competence. In porcine ovarian granulosa cell cultures, 13cRA treatment induced cell cycle progression (G1-S phase transition), and promoted cell proliferation while up-regulating differentiation markers luteinizing hormone receptor (LHR) and progesterone receptor (PGR). Cellular retinoic acid-binding protein CRABP2-mediated mechanisms were identified as pivotal through gain/loss-of-function experiments. Overexpression of CRABP2 amplified 13cRA-induced LHR and PGR expression, while knockdown of CRABP2 by specific siRNA resulted in the opposite effect. The retinoid acid signaling axis was further delineated through receptor-specific modulation. 13cRA promoted RARβ/RXRβ receptor heterodimer formation, with pharmacological activation (Adapalene) potentiating LHR and PGR expression and receptor knockdown diminishing their expression. RA metabolic regulation studies revealed that CRABP1 and CYP26 isoforms (CYP26A1 and CYP26B1) as functional antagonists of 13cRA activity were demonstrated through siRNA silencing or CYP26 inhibitor R115866 treatment experiments. Notably, we identified that FoxA1, as a negative regulator of granulosa cell proliferation and differentiation, mediated the effect of 13cRA on granulosa cell differentiation through siRNA transfection and FoxA1 recombinant protein treatment experiments. 13cRA-mediated FoxA1 expression suppression occurred through CRABP2-dependent nuclear shuttling and RARβ/RXRβ receptor heterodimer activating, with combinatorial modulation of CRABP1/CYP26 system components (CYP26A1 and CYP26B1) significantly altering FoxA1 regulatory dynamics. Finally, we conclude that 13cRA can inhibit FoxA1 expression through RA signaling molecules (CRABP2, RARβ/RXRβ heterodimer, CRABP1, CYP26A1 and CYP26B1) and thus promote the differentiation of porcine ovarian granulosa cells.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"250 ","pages":"117682"},"PeriodicalIF":2.5,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145201352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cyclic guanosine monophosphate (cGMP) improves freezing tolerance of sheep embryos by reducing lipid content.","authors":"Nan Zhang, Cun Zhao, Yupeng Sun, Yukun Song, Yaxin Guo, Wui Sun, Zhiying Wang, Jiaxin Zhang","doi":"10.1016/j.theriogenology.2025.117685","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2025.117685","url":null,"abstract":"<p><p>Embryos produced in vitro exhibit heightened cryosensitivity due to excessive lipid accumulation. Previous studies demonstrated that cyclic guanosine monophosphate (cGMP) modulates intracellular lipid metabolism through cGMP-dependent protein kinase (PKG) signaling in various cell types. This study investigated the effects of cGMP on (i) cryosurvival in sheep embryos, (ii) embryonic quality, and (iii)lipolysis-related parameters. Specifically, we quantified lipid droplet content, free fatty acid levels, and hormone-sensitive lipase (HSL) phosphorylation status as key indicators of lipolytic activity. The results showed that cGMP pretreatment (0.5 mM) for 10 min prior to slow freezing significantly improved post-thaw embryo recovery rates and upregulated the mRNA expression of key developmental genes (POU5F1, SOX2, CDX2, and NANOG). cGMP pretreatment significantly upregulated the expression of multiple lipid catabolism genes (ACSL4, HMGCR, HMGCS1, LIPE, LPL, LIPF, and PLIN2), with LIPE (encoding HSL) exhibiting the most pronounced induction (27.10-fold increase vs. control). Following cGMP pretreatment, PKG activation triggered significant increases in the intracellular Ca²⁺ level and Calcium/Calmodulin-dependent Protein Kinase II (CaMKII) phosphorylation. Given HSL's established sensitivity to calcium fluctuations, this cascade led to markedly enhanced HSL phosphorylation. Concurrently, blastocysts exhibited a significant reduction in lipid droplet content, while transient fatty acid accumulation was observed due to enhanced HSL activity. In summary, pretreating sheep blastocysts with cGMP prior to slow freezing notably elevates their cryotolerance. This enhancement is achieved by triggering the lipolytic activity of HSL via the PKG/CaMKII/Ca²⁺ signaling cascade. This pathway specificity underscores cGMP's potential as a targeted cryoprotectant adjuvant for assisted reproductive technologies, particularly for improving the cryosurvival of lipid-rich embryos.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"250 ","pages":"117685"},"PeriodicalIF":2.5,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145207708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fertility of high-producing multiparous lactating dairy cows inseminated with fresh or frozen sex-sorted Y-chromosome bearing semen from Angus bulls","authors":"P.D. Carvalho ,&nbsp;V.G. Santos ,&nbsp;E. Maia ,&nbsp;S. Westberry ,&nbsp;C. Gonzalez-Marin ,&nbsp;N. Deeb ,&nbsp;J. Moreno ,&nbsp;P.J. Ross","doi":"10.1016/j.theriogenology.2025.117683","DOIUrl":"10.1016/j.theriogenology.2025.117683","url":null,"abstract":"<div><div>The objective of the present study was to evaluate the effect of artificial insemination (AI) with fresh or frozen sex-sorted semen on pregnancies per AI (P/AI) in high producing dairy cows. Multiparous cows were submitted to a Presynch-Ovsynch protocol to receive their first postpartum AI or to an Ovsynch protocol to receive their second and greater service. On the day of AI, cows were randomly assigned to 1 of 3 treatment groups: 1) receive AI with frozen conventional semen (CONV), 2) receive AI with frozen sex-sorted Y-chromosome bearing semen (SS-Frozen), or 3) receive AI with fresh sex-sorted Y-chromosome bearing semen (SS-Fresh). Semen from Angus bulls was used. Conventional semen was used at a concentration of 25 × 10⁶ sperm cells per straw, while both sex-sorted treatments were prepared at 4 × 10⁶ sperm cells per straw. At 32 d after AI, P/AI did not differ between cows receiving AI with CONV and SS-Fresh but was less for cows receiving AI with SS-Frozen (41.2 % vs 39.7 % vs 32.6 %, respectively). Calving per AI followed a similar pattern of the P/AI at 32 d. The proportion of male calves at calving was greater for cows inseminated with sex-sorted semen (91.4 % and 92.3 % for SS-Fresh and SS-Frozen, respectively) compared to cows inseminated with CONV semen (57.4 %). In conclusion, insemination with fresh sex-sorted semen resulted in P/AI comparable to conventional frozen-thawed semen, while insemination with frozen sex-sorted semen resulted in reduced fertility. As expected, the use of sex-sorted Y-chromosome-bearing semen increased the proportion of male beef-on-dairy calves born.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"249 ","pages":"Article 117683"},"PeriodicalIF":2.5,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145117689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pioglitazone (PIO) enhances blastocyst vitrification outcomes via coordinated AQP3-mediated dehydration and antioxidant defense","authors":"Kai-Yan Zhang ,&nbsp;Cai-Yu Wang ,&nbsp;Jing Guo ,&nbsp;Chang-Guo Min ,&nbsp;Jun Wang ,&nbsp;Jing Zhao ,&nbsp;Yi Fang ,&nbsp;Hong-Yu Liu ,&nbsp;He Ding ,&nbsp;Yang Lyu ,&nbsp;Dian Wang ,&nbsp;Xin Ma ,&nbsp;Wen-Fa Lyu","doi":"10.1016/j.theriogenology.2025.117684","DOIUrl":"10.1016/j.theriogenology.2025.117684","url":null,"abstract":"<div><div>Blastocyst cryopreservation is a challenging process due to ice crystallization induced by blastocoel fluid. While aquaporin-3 (AQP3) overexpression improves cryotolerance, there is a lack of pharmacological regulators of AQP3 that can be easily applied in clinical settings. Notably the antidiabetic drug pioglitazone (PIO), despite its association with edema in patients, has been shown to potentially induce cellular dehydration through the modulation of AQP3. Here, we have demonstrated that PIO improves vitrification outcomes by orchestrating AQP3-mediated fluid expulsion and bolstering antioxidant defense mechanisms. Treatment of mouse blastocysts with 2 μM PIO in a hyperosmotic solution resulted in a notable contraction of blastocysts (reduced by 25.95 %, <em>P</em> &lt; 0.01), correlating with 2.6-fold AQP3 up-regulation, compared to the control. This rapid dehydration yielded 95 ± 3.60 % post-thaw survival (vs. 82.5 ± 3.51 % Control, <em>P</em> &lt; 0.001), while also reducing levels of Reactive oxygen species (ROS, <em>P</em> &lt; 0.05) and Dihydroethidium (DHE) (<em>P</em> &lt; 0.05) and increasing levels of glutathione (GSH, <em>P</em> &lt; 0.05) and mitochondrial membrane potential (ΔΨm, <em>P</em> &lt; 0.05) significantly. Mechanistically, PIO reduced DNA damage (γ-H2AX, <em>P</em> &lt; 0.01) while increasing P53 expression (<em>P</em> &lt; 0.01). Crucially, these effects were conserved in bovine Blastocysts, at the concentration of 4 μM, achieving 88.65 ± 8.31 % survival with PIO compared to 82.23 ± 7.48 % in the control group, highlighting the cross-species applicability of the findings Our findings position PIO as a dual-functional cryoadjuvant by coordinating rapid water efflux through AQP3 with antioxidant defense mechanisms. This repurposing approach, leveraging the anti-diabetic agent PIO as a cryo-adjuvant, offers an immediately implementable optimization pathway for the standardized enhancement of animal embryos vitrification protocols.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"250 ","pages":"Article 117684"},"PeriodicalIF":2.5,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145160062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interleukin 17A in the fibrotic-related processes in endometrosis in the mare","authors":"Agnieszka Sadowska ,&nbsp;Anna Wójtowicz ,&nbsp;Tomasz Molcan ,&nbsp;Ewa M. Drzewiecka ,&nbsp;Monika M. Kaczmarek ,&nbsp;Magda Słyszewska ,&nbsp;Graça Ferreira-Dias ,&nbsp;Anna Szóstek-Mioduchowska","doi":"10.1016/j.theriogenology.2025.117680","DOIUrl":"10.1016/j.theriogenology.2025.117680","url":null,"abstract":"<div><div>Equine endometrosis is a chronic degenerative condition with fibrosis being one of the most significant characteristics. A growing body of evidence indicates the critical role of interleukin (IL)-17 in fibrotic disorders. However, its exact role during equine endometrosis remains to be discovered and explained. The main aim of the current study was to establish the expression of IL-17A signaling components in equine endometria with and without endometrosis as well as the effects of IL-17A on the transcriptomic signature, cellular functional characteristics, expression of extracellular matrix (ECM)-associated factors and components of prostaglandin (PGs) signaling in fibroblasts derived from endometrium with and without endometrosis.</div><div>Protein abundance of IL-17 receptor subunit A was up-regulated in endometrium with endometrosis compared to the endometrium without endometrosis. RNA-sequencing results revealed that genes with IL-17A-affected expression in fibroblasts derived from endometrium without endometrosis are involved in e.g., monocyte chemotaxis and macrophage activation, while those with IL-17A-affected expression in fibroblasts derived from endometrium with endometrosis are involved in e.g., neutrophil activation and migration. Moreover, it was found that IL-17A affected the expression and activity of MMPs and TIMPs in the equine endometrial fibroblasts derived from both types of endometrium.</div><div>Interleukin 17A affects the immunomodulatory properties of equine endometrial fibroblasts and the balance between ECM deposition and degradation depending on the origin of fibroblasts - whether derived from endometrium with and without endometrosis.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"249 ","pages":"Article 117680"},"PeriodicalIF":2.5,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145157522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Injectable or non-injectable GnRH analogues for control of swine reproduction. A systematic review and meta-analysis","authors":"Ahm Musleh Uddin ,&nbsp;Gebremeskel Mamu Werid ,&nbsp;Thien D. Van ,&nbsp;Yunmei Song ,&nbsp;Sanjay Garg ,&nbsp;Roy N. Kirkwood ,&nbsp;Kiro R. Petrovski","doi":"10.1016/j.theriogenology.2025.117681","DOIUrl":"10.1016/j.theriogenology.2025.117681","url":null,"abstract":"<div><div>Gonadotropin-releasing hormone (GnRH) analogues are widely applied in swine production to synchronise ovulation and so facilitate fixed-time artificial insemination (FTAI). Both injectable and non-injectable formulations are available; however, their comparative effects on reproductive performance remain unclear. This systematic review and meta-analysis, conducted in accordance with PRISMA guidelines, evaluated the impact of GnRH analogues on conception rate (CR), farrowing rate (FR), weaning-to-estrus interval (WEI), piglets born per litter (PBL), and piglets born alive (PBAL). Random-effect models were used to estimate pooled mean differences (MDs) with 95 % confidence intervals (CIs). Heterogeneity was assessed using the I² statistic, and subgroup analyses compared injectable versus non-injectable regimens. The effect of a subgroup was analysed by administration route, insemination protocol, frequency, or AI method. Across the 27 included studies, GnRH analogue administration did not improve CR (MD = −0.00, 95 % CI: −0.05 to 0.05) or FR (MD = −0.02, 95 % CI: −0.06 to 0.01). Subgroup analyses showed no significant differences between injectable and non-injectable routes for any outcome, and heterogeneity remained low (I² = 0 %). A modest reduction in total PBL (MD = −0.33, 95 % CI –0.57 to −0.08) was evident without effect of subgroup. Although PBAL were slightly reduced (MD = −0.52, 95 % CI –0.82 to −0.22), particularly in subgroups by insemination protocol and insemination frequency there is no biological explanation for this finding. These findings suggest that while GnRH analogues are effective for synchronising ovulation, their influence on litter size is biologically modest. Importantly, non-injectable formulations demonstrated comparable outcomes to injectable approaches, supporting their potential as practical, less-invasive alternatives in commercial settings. To enable robust and parity-specific recommendations, further research should comprise adequately powered, parity-stratified randomised trials in gilts and primiparous (P1) sows. The effects of conventional and post-cervical routes on single FTAI should be assessed. Administration of standardised GnRH analogue dose and timing should be carried out to verify ovulation, control sperm numbers, and pre-specify outcomes (CR, FR, WEI, PBL, and PBAL).</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"250 ","pages":"Article 117681"},"PeriodicalIF":2.5,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145160060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative evaluation of a commercial Tritrichomonas foetus vaccine in infected and uninfected bulls and heifers during a 45-day natural breeding season","authors":"J.H. Koziol ,&nbsp;B.T. Johnson ,&nbsp;C.L. Armstrong","doi":"10.1016/j.theriogenology.2025.117678","DOIUrl":"10.1016/j.theriogenology.2025.117678","url":null,"abstract":"<div><div><em>Tritrichomonas foetus</em> is a venereal protozoan parasite that causes significant reproductive losses in cattle. Bulls act as asymptomatic carriers, transmitting the pathogen to susceptible cows, leading to infertility, embryonic or fetal loss, and other reproductive disorders. With no FDA-approved treatments available, vaccination has become a key control strategy. This study evaluated the reproductive effects of a commercially available killed, whole-cell vaccine (TrichGuard®) administered to both heifers and <em>T. foetus</em>-positive bulls in a natural mating system.</div><div>Heifers and bulls were randomly assigned to one of four vaccine treatment groups. Pregnancy status was monitored, and statistical models assessed pregnancy maintenance and loss. A significant treatment effect was observed on the probability of maintaining pregnancy (P = 0.03), with control (uninfected) heifers showing the highest odds of retention. Vaccinated and infected groups all showed reduced odds of maintaining pregnancy, though post hoc comparisons showed no significant differences amongst any of the vaccination protocols. Pregnancy loss did not differ significantly between groups (P = 0.22). Survival analysis revealed a treatment effect (P = 0.04), driven by the absence of pregnancy loss in the control group.</div><div>These findings suggest that vaccination with the commercially available vaccine Trichguard® may have variable efficacy in reducing reproductive losses in the face of natural infection.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"250 ","pages":"Article 117678"},"PeriodicalIF":2.5,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145134927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}