Animal Reproduction最新文献

{"title":"Impact of lauric acid supplementation on bovine oocyte maturation, IVF embryo development, and stress protection during IVM.","authors":"Nguyen Duc Truong, Do Thi Kim Lanh, Nguyen Thi Ngoc Anh, Nguyen Hoai Nam, Bui Van Dung, Nguyen Van Thanh","doi":"10.1590/1984-3143-AR2025-0095","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0095","url":null,"abstract":"<p><p>This study investigated the effects of lauric acid (LA) supplementation during <i>in vitro</i> maturation (IVM) of bovine oocytes on nuclear maturation and subsequent embryonic development. Cumulus-oocyte complexes (COCs) were matured in medium containing LA at concentrations of 50, 100, 150, 200, or 300 µM, or without LA (control). Embryo development following <i>in vitro</i> fertilization (IVF) and culture (IVC) was assessed. Based on optimal outcomes in the first experiment (A total of 1,558 oocytes were used across 6 - 8 replicates per treatment group),200 µM LA was selected to evaluate its protective role under cellular stress. Oocytes (n = 1,255; five replicates) were matured with or without 200 µM LA and exposed to heat stress (41 °C) or oxidative stress (1 mM H₂O₂). LA supplementation significantly improved blastocyst rates, with 100 - 200 µM groups showing higher formation rates (≥ 37.1%) compared to control (21.3%) (p < 0.05). Blastocyst quality, based on A-B grade embryos, was also enhanced in the 200 µM (51.1%) and 300 µM (56.5%) groups versus control (19.2%) and 50 µM (16.9%) (p < 0.05). Stress exposure reduced maturation and blastocyst rates. Oxidative stress significantly decreased maturation (OS: 44.9%) and blastocyst development (18.6%) compared to control (72.3% and 28.4%, respectively), while LA treatment improved these outcomes (OS-LA: 51.5% and 31.5%) (p < 0.05). Under heat stress, LA showed a non-significant trend toward higher blastocyst rates (24.8%) compared to stress alone (16.2%). Under normal conditions, 200 µM LA significantly enhanced blastocyst yield (44.2%) versus control (28.4%) (p < 0.05). Data were analyzed using ANOVA with post-hoc tests, and differences were considered significant at p < 0.05. These results indicate that LA supplementation during IVM enhances bovine embryo developmental competence and partially mitigates oxidative stress-induced impairment.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250095"},"PeriodicalIF":2.1,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13142084/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Infectious causes of pregnancy loss in cattle: a review of loss intensity and major reproductive pathogens involved.","authors":"Rodrigo de Morais, Giovanna Meireles Borges, Moyses Dos Santos Miranda, Luiz Francisco Machado Pfeifer, Rinaldo Batista Viana, Bruno Moura Monteiro","doi":"10.1590/1984-3143-AR2025-0064","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0064","url":null,"abstract":"<p><p>Pregnancy losses represent one of the main economic problems in cattle farming, where up to half of these losses can be associated with infectious diseases. Early identification of risk factors is essential to prevent reproductive and improve productivity in both beef and dairy systems. However, there are still a few studies in literature that relate etiological agents and the moment of gestation in which these reproductive failures occur. Embryonic and fetal losses vary widely across studies due to differences in diagnostic methods, herd management, pathogen exposure, and environmental conditions. This review summarizes the current scientific evidence on the intensity of pregnancy loss in cattle caused by infectious agents, relating to the most affected gestational stages and the most relevant pathogens. The main etiological agents identified were <i>Neospora caninum</i>, bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1 (BoHV-1), <i>Leptospira</i> spp. and <i>Campylobacter fetus</i>. These infections compromise the reproductive efficiency of herds, causing infertility, embryonic mortality and abortions. <i>Neospora caninum</i> was the main agent associated with pregnancy losses, with abortions reported between the third and ninth months of gestation. BVDV was the second most frequently associated agent. Most pregnancy losses occurred between the second and third thirds of gestation, which makes early diagnosis of reproductive failures and the adoption of effective preventive measures difficult. The intensity and frequency of losses varied according to the agent involved, the geographic region and the type of production system. The findings of this review reinforce the need for continuous reproductive monitoring, especially with the use of pregnancy diagnostics at the end of the breeding season, in addition to the implementation of efficient biosecurity programs on properties.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250064"},"PeriodicalIF":2.1,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13142087/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustained multi-year contraceptive efficacy of single-dose GonaCon in synanthropic female capybaras.","authors":"Derek Andrew Rosenfield, Cristiane Schilbach Pizzutto","doi":"10.1590/1984-3143-AR2025-0142","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0142","url":null,"abstract":"<p><p>Capybaras (<i>Hydrochoerus hydrochaeris</i>) are increasingly synanthropic throughout South America, where their rapid population growth in human-altered landscapes heightens conflicts and, critically, elevates the public health risk of Brazilian Spotted Fever (BSF), a lethal <i>Rickettsia rickettsii</i> zoonosis transmitted by <i>Amblyomma sculptum</i> ticks. Since capybara density is tightly coupled with pathogen circulation, non-lethal, scalable management strategies are essential. We evaluated the long-term efficacy and safety of the single-dose GonaCon™ immunocontraceptive vaccine in free-living, sexually mature female capybaras (n=6 treated, n=3 control) ~ 33 months. All treated females demonstrated sustained reproductive suppression (absence of parturition or estrus behavior; <i>p</i> < 0.01). Efficacy was confirmed by multi-modal evidence: plasma progesterone (P4) and estradiol (E2) concentrations were significantly suppressed, showing reductions of 41% and 36% by Day 27 post-vaccination, respectively (<i>p</i> < 0.005; Cohen's <i>d</i> > 1.5). Histological analysis validated HPG axis disruption, revealing significantly lower ovarian weights (<i>p</i>=0.002) and suppressed folliculogenesis, with treated ovaries possessing drastically fewer antral follicles (mean 2.3 ± 0.5 vs. 12.7 ± 1.2 in controls; <i>p</i><0.001). The treatment was safe, with the only adverse effect being a transient, localized swelling in 4/6 animals that resolved within two weeks. Importantly, treated females maintained critical social behaviors, including alloparental care. These findings provide strong evidence for the sustained, multi-year efficacy of GonaCon in a large wild rodent, supporting its use as a humane, non-surgical tool for density management and BSF risk mitigation under the One Conservation Paradigm.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250142"},"PeriodicalIF":2.1,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13142086/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cryopreservation toxicity and morphological outcomes in <i>Piaractus brachypomus</i> oocytes and embryos.","authors":"Melanie Digmayer, Darci Carlos Fornari, Lis Santos Marques, Jayme Aparecido Povh, Ricardo Pereira Ribeiro, Eduardo Thomé Nicoleti, Leonardo Queiroz Alencar, Louise Nex Spica, Tiantian Zhang, Danilo Pedro Streit","doi":"10.1590/1984-3143-AR2025-0080","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0080","url":null,"abstract":"<p><p>This study evaluated the toxicity of cryoprotectants and the performance of low-rate freezing protocols for oocytes and embryos of <i>Piaractus brachypomus</i>, a Neotropical fish of increasing relevant for Brazilian aquaculture and genetic conservation. Eight cryoprotectant solutions based on methanol (MeOH) or dimethyl sulfoxide (Me₂SO), combined with 0.25 M sucrose in L-15 or HBSS media, were tested for oocytes toxicity at 28 °C and post-freezing viability. In spite of histological and scanning electron microscopy (SEM) analyses indicated preservation of gross morphological features, none of the cryopreserved oocytes supported embryonic development, indicating loss of functional viability following cryoprotectant exposure and freezing. For embryos, two low-rate freezing protocols were evaluated: Protocol 1 (P1E), based on gradual cooling to -13 °C, and Protocol 2 (P2E), involving linear cooling to -60 °C followed by storage in liquid nitrogen. In P1E, eight treatments using 3.1 M MeOH combined with different concentrations of polyvinylpyrrolidone (PVP) or sucrose were tested. The highest proportion of morphologically viable embryos (15.3%) was obtained with MeOT + 0.45 M sucrose (SC5), which different significantly from the other treatments. In contrast, no morphologically viable embryos were recovered after P2E, likely due to inadequate dehydration and intracellular ice formation. Overall, high concentrations of permeant cryoprotectants and prolonged equilibration times were detrimental to oocyte and embryo viability, while sucrose showed better cryoprotective performance than PVP. Even though protocols tested were insufficient to ensure consistent post-thaw viability, the partial success observed in P1E under MeOH and sucrose combinations provides a relevant experimental basis for future refinement of conservation strategies and contributes to development of <i>ex situ</i> germoplasm conservation approaches for <i>P. brachypomus</i> and other Neotropical species.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250080"},"PeriodicalIF":2.1,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13142085/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of donor breed and season of year on <i>in vitro</i> beef embryo production and recipient pregnancy rate.","authors":"Brenda Matos Fernandes, Gustavo Pereira Cadima, Natani Silva Reis, Ricarda Maria Dos Santos","doi":"10.1590/1984-3143-AR2025-0042","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0042","url":null,"abstract":"<p><p>Approximately 85% of embryos produced in Brazil are <i>in vitro</i> (IVP). However, the success of IVP is still quite diverse, and several factors need to be coordinated to obtain a live calf from an oocyte. This study aims to evaluate the influence of the donor breed (Nellore <i>vs</i>. Senepol) and the seasons of year (Dry <i>vs</i>. Rainy) at the time of follicular aspiration (OPU) on the number of viable oocytes and embryos produced, and the recipients pregnancy rate per embryo transfer (P/ET). Data from 368 donors was evaluated, 198 Senepol and 170 Nellore, resulting in a total of 21,758 oocytes collected by OPU. During the period a total of 4,740 embryos were produced (2,135 Senepol and 2,605 Nellore) and 2,124 fresh embryo transfers were analyzed. A negative effect of dry season was observed on number of total and viable oocytes for Nellore. The embryo production rate was lower for Senepol in both periods. Nellore breed had lower embryo production rate in the rainy period. The P/TE was lower for embryos from Senepol donors during dry season, while the P/TE of embryos from Nellore donors was not affected by season. In conclusion, the dry season negatively influences total and viable oocyte collection in Nellore donors, while in Senepol donors remained constant throughout the year. The embryo production of Nellore donors is negatively influenced by rainy season, although it remains higher than the Senepol donors throughout the year, and P/TE of the embryos of Senepol donors is reduced during the dry season.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250042"},"PeriodicalIF":2.1,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13075774/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147687888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Follicular dynamics and hormonal profile in Prepubertal nelore and Murrah heifers subjected to fixed-time artificial insemination (FTAI).","authors":"Isabella de Oliveira Bêta, Larissa de Paiva Nunes Gonçalves, Aline Pacheco, Yana Eliza Feitosa de Almeida, Alisson Jordão Prado, Pietro Sampaio Baruselli, Kedson Alessandri Lobo Neves, Antonio Humberto Hamad Minervino","doi":"10.1590/1984-3143-AR2025-0010","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0010","url":null,"abstract":"<p><p>We aimed to evaluate puberty induction, follicular dynamics, and hormonal profiles of progesterone (P4) and estradiol (E2) in prepubertal Nelore and Murrah heifers subjected to synchronization for fixed-time artificial insemination (FTAI). Six Nelore heifers (14 to 17 months old; 320 to 350 kg) and six Murrah heifers (14 to 17 months old; 422 to 523 kg) confirmed as prepubertal by ultrasonography due to the absence of a corpus luteum were used. The protocol included an intravaginal P4 device (0.5 mg) on D0, along with the administration of estradiol benzoate (EB) and prostaglandin F2α. In Nelore, the device was removed on D7, followed by the administration of estradiol cypionate, prostaglandin F2α, and eCG, with insemination occurring 48-56 hours after intravaginal device removal (D9). In Murrah, the device was removed on D9, followed by prostaglandin F2α and Ecg administration, with insemination on D12 after GnRH administration (D11). Blood samples were collected (Nelore: D7 and D9; Murrah: D9 and D12) to measure hormone levels, and ultrasonography monitored follicular dynamics and ovulation. The ovulatory follicle diameter was 7.83 ± 2.25 mm (Nelore) and 7.7 ± 1.63 mm (Murrah), with no significant differences (P > 0.05). The dominant follicle diameter at P4 device removal was 6.5 ± 1.59 mm (Nelore) and 6.9 ± 4.97 mm (Murrah). The mean P4 levels were 0.76 ng/mL (Nelore) and 1.42 ng/mL (Murrah) at P4 device removal, and 1.00 ng/mL and 0.52 ng/mL at the moment of FTAI. The mean E2 levels were 9.28 pg/mL (Nelore) and 26.75 pg/mL (Murrah) at the P4 device removal, and 11.20 pg/mL and 11.59 pg/mL at the moment of FTAI. Ovulation rates were 100% in Nelore and 50% in Murrah. These results highlight the importance of tailoring FTAI protocols to the specific reproductive characteristics of each breed.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250010"},"PeriodicalIF":2.1,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13142083/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147832062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emerging imaging modalities for the diagnosis of malignant lesions of the male reproductive tract in companion animals.","authors":"Diego Rodrigues Gomes, Anna Carolina Mazeto Ercolin, Gabriela Castro Lopes Evangelista, Felipe Farias Pereira da Câmara Barros, Camila Silveira Stanquini, Camila Debastiani, Fredderico Garcia, Marcus Antônio Rossi Feliciano","doi":"10.1590/1984-3143-AR2025-0124","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0124","url":null,"abstract":"<p><p>Understanding diseases that affect the male reproductive system of dogs and cats is important for improving their health and quality of life. Imaging techniques, such as ultrasound and X-rays, play a fundamental role in the evaluation of this system. They help veterinarians detect problems in the testicles, prostate, and other reproductive organs of dogs and cats. In recent years, advanced ultrasound methods, such as Doppler, elastography, and contrast-enhanced ultrasound, have become more accessible and allow earlier and more accurate diagnosis. Although definitive diagnosis of neoplastic lesions depends on cytological or histopathological examinations, radiography and advanced ultrasonography contribute significantly to early detection and malignancy characterization. This literature review explores the main imaging techniques used in the investigation of malignant lesions in the male reproductive tract of dogs and cats, namely radiography, B-mode and Doppler ultrasonography, elastography, and contrast-enhanced ultrasonography (CEUS). The goal is to help veterinarians make better decisions and improve care for their patients. The integration of these modalities has become well established in human medicine and shows growing applicability in veterinary practice, allowing for real-time, non-invasive assessment of the testes, prostate, penis, and scrotal structures. The compiled data highlight the potential of combining different imaging modalities to improve diagnostic accuracy and provide clinical and surgical support in the management of malignant lesions affecting the male reproductive tract in dogs and cats.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250124"},"PeriodicalIF":2.1,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13075779/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147687870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative evaluation of sperm parameters in Italian (<i>Apis mellifera ligustica</i>) and Africanized (<i>Apis mellifera</i>) honeybee drones from the Caatinga biome.","authors":"Lilian Leal Dantas, Andréia Maria da Silva, Leandro Alves da Silva, Pedro Augusto Pinheiro Brito, Yuri Gonçalves Matos, Romário Parente Santos, Kátia Peres Gramacho, Alexandre Rodrigues Silva","doi":"10.1590/1984-3143-AR2025-0113","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0113","url":null,"abstract":"<p><p>Bees are essential pollinators with species differing morphologically and physiologically. Understanding the variations in reproductive parameters between phenotypes is crucial. This study compares the sperm characteristics of Italian (<i>Apis mellifera ligustica</i>) and Africanized drones (<i>Apis mellifera L.</i>) raised in the Caatinga biome. Nine sexually mature Italian drones and sixteen Africanized drones from different colonies were used. Semen was collected using the endophallus eversion technique and diluted in saline solution (1:20). The parameters analyzed included: motility (optical microscopy), sperm viability (Hoechst 33342; propidium iodide), functional integrity of the plasma membrane (hypo-osmotic test), morphology and morphometry (Rose Bengal), and scanning electron microscopy. The results were expressed as mean ± standard error. Statistical analyses included the Shapiro-Wilk test to the normality of residuals and the Bartlett test to verify homoscedasticity. Comparisons between groups were performed using the Mann-Whitney and Student's t-tests (P < 0.05). Both phenotypes presented 90% sperm motility with viability of 82.4 ± 2.5% for Italians and 81.1 ± 2.4% for Africanized ones; the functional integrity of the plasma membrane was 93.4 ± 1.8% and 91.6 ± 1.5%, respectively. Regarding morphology, the percentage of normal sperm was 10.89 ± 1.66% for Italian and 12.06 ± 1.01% for Africanized, with the curled tail being the most predominant feature of sperm morphology. No statistically significant differences (P > 0.05) were observed for the above-mentioned parameters. Sperm head morphometry was significantly larger (P < 0.05) in Italian (10.04 ± 0.03 µm) compared to Africanized (9.33 ± 0.04 µm). Scanning electron microscopy analysis revealed no ultrastructural differences between phenotypes. In conclusion, there is a high degree of similarity in sperm parameters of both phenotypes under the same environmental conditions, indicating the feasibility of applying similar reproductive strategies.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250113"},"PeriodicalIF":2.1,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13075775/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147687811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tricaine methanesulfonate and eugenol during semen collection do not affect fertilization and hatching rates on <i>Rhamdia quelen</i>.","authors":"Nathalia Dos Santos Teixeira, Lis Santos Marques, Rômulo Batista Rodrigues, Thales de Souza França, Jhony Lisbôa Benato, Maritza Pérez Atehortúa, Darlan Gusso, Itamar Cossina Gomes, Thaiza Rodrigues de Freitas, Henrique Mautone Gomes, Helen Tais Rosa-Silva, Alexandre Kleber Silveira, José Claudio Fonseca Moreira, Danilo Pedro Streit","doi":"10.1590/1984-3143-AR2024-0107","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2024-0107","url":null,"abstract":"<p><p>The reproduction of some fish species in captivity is only possible by imposing artificial reproductive procedures, and the manipulation of fish for these purposes is a stressor. Thus, anesthesia can reduce stress during handling. However, it is necessary to investigate the possible side effects on breeding and the general health of the animal. Therefore, we aimed to investigate the impact of tricaine methanesulfonate (MS-222) and eugenol (EUG) at concentrations of 300 mg L^-1 and 40 mg L^-1, respectively, on several stress- and reproductive-related parameters in <i>Rhamdia quelen</i> anesthetized before semen collection. After hormonal induction, 24 sexually mature males (534.4 ± 259 g) were randomly assigned to treatment groups and semen and blood samples were collected. Anesthesia recovery and induction time were extended in fish anesthetized with EUG; however, plasma cortisol concentrations did not differ among the treatment groups. EUG caused higher DNA fragmentation in blood cells than in the control group (without anesthesia). EUG increased the monocyte count compared to the other experimental groups. MS-222 showed a lower sulfhydryl group (SH) quantitation than the other experimental groups. The anesthetics used before semen collection in this study had no adverse effects on the fertilization or hatching capacity of anesthetized <i>R. quelen</i>. MS-222 (300 mg L^-1) and EUG (40 mg L^-1), despite being related to hematological and semen changes, did not negatively affect the reproductive capacity of <i>R. quelen</i> males. Thus, anesthesia is recommended for <i>R. quelen</i> during semen collection, considering reproductive parameters and animal welfare.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20240107"},"PeriodicalIF":2.1,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13075778/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147687865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gilts not detected in estrus in a batch farrowing breeding herd: a hormonal strategy to improve gilt utilization.","authors":"Monike Willemin Quirino, Michele Dezordi Franz, Arthur Martelli, Thomaz Lucia, Fabiana Moreira, Vanessa Peripolli, Bernardo Garziera Gasperin, Rafael da Rosa Ulguim, Ivan Bianchi","doi":"10.1590/1984-3143-AR2025-0131","DOIUrl":"https://doi.org/10.1590/1984-3143-AR2025-0131","url":null,"abstract":"<p><p>This study evaluated reproductive performance of gilts classified as in anestrus in a batch farrowing system. Thirty-three gilts not expressing estrus within 40 days post-arrival were treated with chorionic gonadotropins, with blood collected for progesterone (P4) analysis on the same day. Thirteen gilts expressed estrus within 7 days, and 12 were inseminated (232.8 ± 2.1 days old), with 11 farrowing (91.7%; 14.2 ± 0.83 total piglets). Nineteen gilts had P4 ≤ 2.6 ng/mL at treatment; among the 20 non-responders, 10 had P4 > 2.6 ng/mL. A strong association was observed between P4 levels (≤ 2.6; > 2.6 and < 19; ≥ 19 ng/mL) and the responsiveness of gilts to gonadotropin treatment (<i>P</i> < 0.01; Cramér's V = 0.63), with greater responsiveness in gilts with P4 levels ≤ 2.6 ng/mL. Non-responsive gilts (<i>n</i> = 20) received Altrenogest for 10 - 11 days, with 17 showing estrus within 10 days and 15 farrowing (88.2%; 14.3 ± 0.84 total piglets). Estrus detection failures and silent heat likely caused misdiagnosis. Gonadotropin, with or without Altrenogest, reduced culling ~8-fold, allowing 41-58% of gilts to reach at least the 3^rd farrowing.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"23 2","pages":"e20250131"},"PeriodicalIF":2.1,"publicationDate":"2026-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13004552/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147497387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}