Animal Reproduction最新文献

{"title":"L-Carnitine enhances porcine sperm quality, longevity, and zona pellucida binding in cooled semen.","authors":"Monique de Albuquerque Lagares, Nathalia Abreu Amaral, Joyce Junia Braga, Natalia de Castro Alves, Marina Morra Freitas, Rafael Romero Nicolino, Raphael Rocha Wenceslau, Fernanda da Rocha Anselmo, Marina Maria do Carmo Silva Oliveira, Eduardo Damasceno Costa, Fernanda Radicchi Campos Lobato de Almeida, Rubens Stahlberg","doi":"10.1590/1984-3143-AR2023-0143","DOIUrl":"10.1590/1984-3143-AR2023-0143","url":null,"abstract":"<p><p>Porcine breeding industries typically ensure the viability of boar artificial insemination doses during a 5-day liquid storage period at 17 °C. This study aimed to investigate whether the addition of L-carnitine (LC) to boar semen doses on different days of cooled storage could extend their usability. In experiment 1, LC was added to porcine semen doses on the fifth day (d5) of cooled storage performing five treatments control (no LC), 0.5, 1-, 5- and 10-mM LC. On d6 and d8 of storage, semen samples were evaluated for sperm motility and kinematic parameters, membrane functionality, and hydrogen peroxide and nitrite concentrations. In experiment 2, the number of sperm bound to the zona pellucida (ZP) was determined, as a way to investigate sperm penetration capability from boar insemination doses, with co-incubation with porcine oocytes. LC concentration that produced the most favorable outcomes in Experiment 1 was chosen to experiments 2 and 3, performing two treatments in the absence and with the LC. In Experiment 3, LC was added to cooled porcine semen doses after one day of storage (d1), and the same evaluations of experiment 1 were conducted on days 5, 7, 9, and 12, including sperm membrane integrity. The addition of 10 mM LC on d5 and d1 of storage improved sperm motility, which was extended up to 8 and 12 days of cooled storage, respectively. LC addition on d5 of storage increased sperm membrane functionality, while when added to semen on d1 of storage, it decreased NO₂ ^- concentration on d9. On d6 of cooled storage 10 mM LC increased the number of sperm bound to ZP compared to the control. In conclusion, adding 10 mM LC to porcine semen doses at 17 °C improved sperm characteristics and ZP binding, ultimately enhancing sperm viability for up to 12d.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20230143"},"PeriodicalIF":1.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864729/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143514376","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 exogenous GnRH administration at insemination on pregnancy rates of estrus-synchronized seven ewe populations during the breeding season.","authors":"Shuyuan Sun, Nana Yang, Jing Zhang, Xinglong Wu, Yiyong Liu, Xiangyun Li","doi":"10.1590/1984-3143-AR2024-0085","DOIUrl":"10.1590/1984-3143-AR2024-0085","url":null,"abstract":"<p><p>The objective of this study was to investigate the effects of GnRH at insemination on pregnancy and lambing in seven ewe populations during the breeding season. Estrus was synchronized in 1560 adult ewes using an intravaginal sponge impregnated with flurogestone acetate. The sponge was left in the vagina for 12 days followed by an injection of 330 IU of eCG at sponge removal. Each ewe was inseminated twice at 48 h and 60 h after sponge removal. The treatment group was intramuscularly injected at the first insemination with a dose of 16 μg GnRH and the control group with saline solution in each ewe population. The results showed that GnRH administration significantly decreased the pregnancy rate in three ewe populations, but had no effects in four ewe populations. Additionally, the litter size tended to increase in the treatment group compared to the control group in all seven ewe populations, but the difference was not significant. In conclusion, GnRH administration at insemination was not recommended for ewes undergoing a timed artificial insemination during the breeding season. The breed/population may be a critical determinant of the potential for exploiting GnRH application in sheep breeding programs.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20240085"},"PeriodicalIF":1.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864727/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143514375","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":"Anti-mullerian hormone (AMH) in pregnant buffaloes: maternal and fetal plasma concentrations and immunolocalization in the fetal gonads.","authors":"Nathalia Nogueira da Costa, Maria Auxiliadora Pantoja Ferreira, Priscilla do Carmo Azevedo Ramos, Alessandra Ximenes Santos, Marcela da Silva Cordeiro, Priscila di Paula Bessa Santana, Vanessa Cunha Brito, Thiago Velasco Guimarães Silva, Bruno Porpino Homobono, Eduardo Baia de Souza, William Allan King, Moyses Santos Miranda, Simone Socorro Damasceno Santos","doi":"10.1590/1984-3143-AR2023-0152","DOIUrl":"10.1590/1984-3143-AR2023-0152","url":null,"abstract":"<p><p>Anti-Müllerian Hormone (AMH), a member of the TGF-β superfamily, plays a critical role in mammalian fertility. This study aimed to investigate AMH concentrations in pregnant buffalo cows and their fetuses, and to characterize the cellular distribution and immunolocalization of AMH within fetal gonads. Gonads were collected from 12 male and 14 female buffalo fetuses, fixed in 10% buffered formalin, and processed for routine histological analysis and immunohistochemical localization of AMH. Blood samples were collected from 26 pregnant buffalo cows and their corresponding fetuses into EDTA-coated tubes. AMH levels in both maternal and fetal blood were quantified using a commercially available bovine AMH ELISA kit. Significant (p < 0.05) inter-individual variations in maternal and fetal AMH concentrations were observed. In males, fetal AMH concentrations increased significantly with gestational age, with levels substantially higher compared to females at all gestational ages (52-1222 times higher). Immunohistochemistry revealed intense AMH immunoreactivity in the cytoplasm of pre-Sertoli cells in male fetuses. In females, no significant correlation was found between fetal AMH concentrations and follicular populations, although intense AMH immunostaining was observed in the cytoplasm of oocytes within primordial follicles. These findings suggest that fetal AMH concentrations in buffaloes are influenced by gestational age and sex, and that fetal AMH likely does not readily cross the placental barrier. Further investigations are warranted to elucidate the intricate role of AMH in gonadal development and function in buffaloes.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20230152"},"PeriodicalIF":1.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864731/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143514368","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":"Beef cows with larger vulvar width have greater antral follicle count, viable oocytes, and higher circulating AMH.","authors":"Renata Maculan, Gisvani Lopez de Vasconcelos, Jesús Alfonso Sánchez Viafara, Gabriel Miranda Moreira, Cintia Vanin, Nathalia Alves, Marcos Brandão Dias Ferreira, José Camisão de Souza","doi":"10.1590/1984-3143-AR2024-0077","DOIUrl":"10.1590/1984-3143-AR2024-0077","url":null,"abstract":"<p><p>Owing to the low heritability of reproductive traits, the search for markers and their interrelationship that could indicate reproductively superior individuals is important in the selection process for bovine reproductive efficiency. This study aimed to investigate the possible interrelationships between the antral follicle count (AFC), vulvar-width (VW), anti-Müllerian hormone (AMH) concentrations, fertility in <i>Bos Taurus</i> and <i>Bos Indicus</i> females. Brahman (<i>Bos Taurus-Indicus</i>, <i>n =</i> 126) and Simmental and Angus (<i>Bos Taurus-Taurus</i>, <i>n =</i> 155) cows were classified as having large (≥86 mm) and small (<86 mm) VW. From each group, one blood sample per animal was collected to determine the AMH serum concentrations. The GLIMMIX procedure in SAS^® was used to determine whether vulva width (VW) and AMH classes, associated or not with breed, could influence the age at first calving (FCA), calving to first service interval (CFSI), calving interval (CI), number of services per pregnancy (SP), and number of viable oocytes (VO). Antral follicle count (AFC) (36.10 ± 1.90 vs. 22.78 ± 1.64, for large and small VW, respectively), AMH (1.17 ± 0.07 vs. 0.48 ± 0.007 ng/mL), and viable oocytes or VO (18.86 ± 1.76 vs. 10.15 ± 1.49) were greater (<i>P</i> < 0.05) in the large VW than in the small VW. Brahman cows had greater AFC (36.30 ± 1.34 vs. 22.09 ± 1.67), VW (106.94 ± 15.83 vs. 69.78 ± 14.11 mm), and AMH (1.18 ± 0.07 vs. 0.42 ± 0.05 ng/mL) compared to that of taurine cows. In conclusion, VW was an efficient predictor of AFC and AMH concentrations in both genetic groups, but under the conditions of this trial no link could be detected between these variables and the reproductive indices studied.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20240077"},"PeriodicalIF":1.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864730/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143514369","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":"Sperm vitrification <i>of Prochilodus brevis</i>: influence of diluent, stored volume and supplementation with sulfated polysaccharides of Nile tilapia (<i>Oreochromis niloticus</i>) skin.","authors":"Priscila Silva de Almeida-Monteiro, Romulo Roberto Ribeiro Pinheiro, Mayara Setúbal Oliveira-Araújo, Thais Maia Torres, Renata Vieira do Nascimento, Vanessa Alves Pereira, Yasmim Maia Ferreira, Yara Silvino Sales, Jéssica Sales Lobato, Ianna Wivianne Fernandes Araújo, José Ariévilo Gurgel Rodrigues, Assis Rubens Montenegro, Carminda Sandra Brito Salmito-Vanderley","doi":"10.1590/1984-3143-AR2024-0075","DOIUrl":"10.1590/1984-3143-AR2024-0075","url":null,"abstract":"<p><p>The aim of this study was to evaluate the influence of diluent, stored volume and the cryodiluent medium supplementation with sulfated polysaccharides (SP) extracted from Nile tilapia skin on <i>P. brevis</i> vitrified sperm. Six pools were diluted in 5% Glucose or Powder Coconut Water (ACP-104), supplemented or not with 0.5 mg/mL of SP, and submitted to vitrification. Subsequently, they were stored in cryotubes in two volumes (60 μL and 420 μL). After 15 days, the samples were devitrified and evaluated for kinetics, membrane integrity and sperm DNA integrity. ACP-104 proved to be the best diluent for <i>P. brevis</i> sperm vitrification. Membrane and DNA integrity rates were higher (P < 0.05) when stored in smaller and larger volume, respectively. Additionally, the best rates (P < 0.05) of these same parameters were obtained with supplemented medium. There was interaction (P < 0.05) between diluent and stored volume, with ACP-104 exceeding 5% Glucose for motility in both volumes, while for average path speed (VAP) and membrane integrity the same happened in the larger volume. 5% Glucose had higher VAP and membrane integrity when stored in smaller volume. There was a triple interaction (P < 0.05) for DNA integrity, and better results were obtained when semen was vitrified in ACP-104 and stored in the larger volume, regardless of supplementation, which influenced only the 5% Glucose medium in the smaller volume. It was concluded that ACP-104, supplemented with SP and stored in larger volume make up the best treatment for <i>P. brevis</i> sperm vitrification.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20240075"},"PeriodicalIF":1.6,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11813166/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143397980","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":"Reproductive traits and economic aspects on dairy cattle.","authors":"Jeferson Bello Dos Santos, Bruna Waddington de Freitas, Isaac Andres Mora Obando, Natan Dias de Oliveira, Jurandy Mauro Penitente-Filho, Marcus Vinicius Castro Moreira, André Navarro Lobato, José Domingos Guimarães","doi":"10.1590/1984-3143-AR2024-0050","DOIUrl":"10.1590/1984-3143-AR2024-0050","url":null,"abstract":"<p><p>This study aimed to characterize the reproductive parameters and economic indicators of dairy farms. Data were from technical assistance of the <i>Programa de Desenvolvimento em Pecuária Leiteira</i> (PDPL-UFV) including 26 farms, from September 2022 to August 2023, comprising an entire production cycle. The following economic indicators were selected as dependent variables: Unit Net Margin (UNM), Operating Profitability (OP) and Rate of Return on Capital (RRC). Reproductive parameters were used as explanatory variables in multiple linear regression analysis. A stepwise selection was performed and only variables significant at <i>p</i> < 0.10 were kept in the final model. Pregnancy rate of cows, number of inseminations per pregnant heifer, and replacement rate were the reproductive parameters with the greatest effect on the evaluated economic indices. The UNM and OP were positively affected by pregnancy rate of cows and number of inseminations per pregnant heifer, but replacement rate negatively affected both indices. Only the pregnancy rate of cows showed a significant and positive effect on RRC. Results suggest that the economic viability of a dairy farm is not only associated with cutting costs such as reducing the number of inseminations in heifers, or increasing revenue by selling animals, which increases the replacement rate.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20240050"},"PeriodicalIF":1.6,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11801145/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143363508","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":"Swine clones: potential application for animal production and animal models.","authors":"Thaís Naomi Gonçalves Nesiyama, Juliano Rodrigues Sangalli, Tiago Henrique Camara De Bem, Kaiana Recchia, Simone Maria Massami Kitamura Martins, André Furugen Cesar de Andrade, Juliana Germano Ferst, Gustavo Henrique Doná Rodrigues Almeida, Mariana Groke Marques, Renata Gebara Sampaio Dória, Adriano Bonfim Carregaro, Marcus Antônio Rossi Feliciano, Maria Angélica Miglino, Fabiana Fernandes Bressan, Felipe Perecin, Juliano Coelho da Silveira, Lawrence Charles Smith, Vilceu Bordignon, Flávio Vieira Meirelles","doi":"10.1590/1984-3143-AR2024-0037","DOIUrl":"10.1590/1984-3143-AR2024-0037","url":null,"abstract":"<p><p>Somatic cell nuclear transfer (SCNT), or cloning, is used to reprogram cells and generate genetically identical embryos and animals. However, the cloning process is inefficient, limiting its application to producing valuable animals. In swine, cloning is mainly utilized to produce genetically modified animals. Indeed, recombinant DNA technologies have evolved considerably in recent years, with homologous recombination and gene editing technologies becoming more efficient and capable of recombining both alleles in a single cell. The selection of appropriate cells and their use as nuclear donors for SCNT is the most common method for generating edited and genetically modified animals for commercial and research purposes. This article reviews current applications of swine cloning and shares our personal experiences with the procedure in this species.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20240037"},"PeriodicalIF":1.6,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758785/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143045022","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":"Reactive oxygen species attenuation improves the quality of vitrified-warmed bovine embryos.","authors":"Viviane Luzia da Silva Feuchard, Clara Slade Oliveira, Naiara Zoccal Saraiva, Carolina Capobiango Romano Quintão, Leticia Zoccolaro Oliveira","doi":"10.1590/1984-3143-AR2024-0035","DOIUrl":"10.1590/1984-3143-AR2024-0035","url":null,"abstract":"<p><p>The aim of this study was to investigate the effects of modulating reactive oxygen species (ROS) in vitrified bovine in vitro produced (IVP) embryos. In experiment I we compared ROS production in fresh and vitrified-warmed blastocysts. In experiment II we evaluated the effects of antioxidant supplementation (100 μM of 2-mercaptoethanol; BME; 0 h to 2 h during warming) on ROS levels in vitrified-warmed blastocysts, and in experiment III we compared the development of fresh and vitrified-warmed blastocysts in the presence (BME) or absence (Control) of antioxidant (100 μM BME; 0 h to 48 h during warming). Higher ROS production (Fresh: 68.48 ± 7.92 <i>vs</i> Vitrified: 123.53 ± 13.15; P<0.05) and lower cell number was observed in vitrified compared to fresh embryos (Fresh: 123.01 ± 5.67 <i>vs</i> Vitrified: 103.04 ± 4.25; P<0.05). Antioxidant supplementation reduced ROS levels (Vitrified: 38.24 ± 1.27 vs. Vitrified/BME: 33.54 ± 1.08; P<0.05) and increased cell number in treated embryos (Vitrified: 100.65 ± 3.98 <i>vs</i>. Vitrified/BME: 112.95 ± 3.72; P<0.05). No differences were observed in the re-expansion rates of vitrified embryos cultured in the absence and presence of BME at 0, 2, and 4 h after warming (P>0.05). The embryo hatching rate did not differ (P>0.05) among embryos from the fresh, vitrified and vitrified/BME groups. However, the total cell numbers were higher (P<0.05) in vitrified embryos supplemented with BME (143.02 ± 6.97) than in vitrified embryos without BME (113.25 ± 5.09) but similar (P>0.05) to that observed in fresh embryos cultured with (150.54 ± 8.99) and without BME (142.71 ± 13.60). It was concluded that the vitrification and warming processes increased ROS levels in blastocysts and its attenuation with BME antioxidant improved embryonic quality.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20240035"},"PeriodicalIF":1.6,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758786/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143045010","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":"The protective effect of zinc oxide nanoparticles on boar sperm during preservation at 17 °C.","authors":"Qimeng Hu","doi":"10.1590/1984-3143-AR2023-0013","DOIUrl":"10.1590/1984-3143-AR2023-0013","url":null,"abstract":"<p><p>More than 90% of spermatozoa of boars in pork producing countries is stored in liquid at 17 °C; however, the quality of these spermatozoa is affected by bacterial breeding and oxidative damage. This study analyzed sperm quality and sperm capacitation after storage to study the effects of the effects of ZnO nanoparticles (ZnO NPs) supplementation on seminal plasma (SP)-free sperm preservation. We investigated the effects of adding 20, 50, 100 and 200 μg/mL of ZnO NPs to a seminal free boar sperm diluent over a 7-day period at 17 °C to assess the changes in non-capacitated/capacitated sperm quality parameters, antioxidant capacity, ATP content and extent of protein tyrosine phosphorylation. The addition of different doses of ZnO NPs to stored sperm did not induce significant effects on the sperm motility and ATP content when compared to the sperm without ZnO NPs treatment. However, the addition of 50, 100, 200 μg/mL ZnO NPs to stored sperm improved total antioxidant capacity (T-AOC) and CuZn-superoxide dismutase (CuZn-SOD) (<i>p</i> < 0.05). ZnO NPs also reduced the malondialdehyde (MDA) content of the preserved sperm (<i>p</i> < 0.05). Moreover, our results indicate that the supplementation of 50 μg/mL ZnO NPs to preserved sperm improved the sperm membrane integrity (<i>p</i> < 0.05). ZnO NPs exerted protective effects on protein tyrosine phosphorylation, especially with regards to membrane proteins. Following incubation and capacitation, sperm exhibited good levels of protein tyrosine phosphorylation and ATP levels with high T-AOC and CuZn-SOD activity and low MDA content. ZnO NPs exerted protective capacity to a preservation extender used for SP-free boar sperm during storage at 17 °C. The optimal concentration of ZnO NPs for preservation extender was 50 μg/mL.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20230013"},"PeriodicalIF":1.6,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758902/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143045032","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":"Absence of mating behaviors in the female dogs neonatally treated with estrogen and progesterone.","authors":"ChanJin Park, Kayla Tando, Sandra Soto-Heras, Sherry Zhou, Po-Ching Lin, CheMyong Ko","doi":"10.1590/1984-3143-AR2024-0080","DOIUrl":"10.1590/1984-3143-AR2024-0080","url":null,"abstract":"<p><p>This study aimed to develop a non-surgical method to neutralize reproduction in female dogs. Female Beagle puppies, aged 6 days, were treated with pellets designed to release estradiol benzoate (EB; 1.0 mg) and progesterone (P4; 5.0 mg) over approximately 3 weeks. Their estrous cycles were monitored from 6 to 34 months of age by examining their vulvas daily and measuring their serum P4 levels once a month. Vulvar edema and discharge, followed by a serum P4 level above 5 ng/ml, indicated the potential estrus. Each time a dog showed these signs, breeding was attempted by housing with a proven male Beagle. All the treated dogs displayed cyclic progesterone surges with 5 to 6-month-long anestrous intervals. Surprisingly, none exhibited sexual behaviors, and no mating occurred (i.e., no intromission and copulatory tie), resulting in no pups being born. This phenomenon was further explored in laboratory animals. Neonatal female rats were treated with microspheres containing smaller doses of the same steroids (0.3 mg EB + 3.0 mg P4) at 1 or 2 days old. At 3 months old, the rats were ovariectomized, chemically stimulated to exhibit estrus behaviors using a standard protocol and tested for receptivity to proven male rats. Untreated control rats showed normal receptivity (i.e., lordosis) and allowed males to mate. However, rats treated with EB+P4 did not exhibit lordosis or allow mating. These results indicate that the combined use of estrogen and progesterone could be an effective non-surgical method for inhibiting mating behavior and, consequently, neutralizing female dog reproduction.</p>","PeriodicalId":7889,"journal":{"name":"Animal Reproduction","volume":"22 1","pages":"e20240080"},"PeriodicalIF":1.6,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758777/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143045544","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}