Animal Reproduction (AR)
https://animal-reproduction.org/article/doi/10.1590/1984-3143-AR2023-0118
Animal Reproduction (AR)
REVIEW ARTICLE

Use of chorionic gonadotropins during lactation to optimize postpartum sow reproductive performance: a review

Monike Willemin Quirino; Carolini Schultz; Michele dos Passos Dezordi Franz; Thomaz Lucia Jr; Arthur Martelli; Paulo Bayard Dias Gonçalves; Rafael da Rosa Ulguim; Bernardo Garziera Gasperin; Ivan Bianchi

Downloads: 1
Views: 220

Abstract

Treating lactating sows with chorionic gonadotropins may allow controlling their post-weaning reproductive function, despite the occurrence of anestrous during lactation. This article reviews the potential effectiveness of treatment with both equine and human chorionic gonadotropins (eCG and hCG, respectively) during lactation on the control of estrus expression and ovulation in weaned sows. The use of 1,000 IU hCG at 24 and 48 h postpartum may induce ovulation in the treated sows, but the ovulation rate may be variable. Pregnancy rates may be improved with combined treatment after the second week of lactation with both chorionic gonadotropins: 1,500 IU eCG plus 500 – 1,000 hCG; or 1,000 IU eCG plus 1,000 IU hCG. Treatment with eCG (1,000 – 2,000 IU) at the end of lactation may result in acceptable estrus expression and ovulation rates, although with marginal benefit for pregnancy rates. The subsequent response to treatments with chorionic gonadotropins during lactation is likely influenced by the treatment period, the suckling frequency during lactation, and the boar exposure during the weaning-to-estrus interval. A better understanding of the efficiency of such steroid-free treatments is increasingly relevant due to the constraints of the use of steroid hormones in livestock reproductive management.

Keywords

hormone therapy, lactation, estrus, ovulation, sows

References

Almeida FRCL, Dias ALNA. Pregnancy in pigs: the journey of an early life. Domest Anim Endocrinol. 2022;78:106656. http://doi.org/10.1016/j.domaniend.2021.106656. PMid:34474228.

Am-in N, Techakumphu M, Kirkwood R. Effect of altering the ratio of exogenous gonadotropins on reproductive performance of primiparous sows during the seasonal infertility period. Can J Anim Sci. 2018;99(1):202-5. http://doi.org/10.1139/cjas-2018-0060.

Armstrong JD, Esbenshade KL, Coffey MT, Heimer E, Campbell R, Mowles T, Felix A. Opioid control of growth hormone in the suckled sow is primarily mediated through growth hormone releasing factor. Domest Anim Endocrinol. 1990;7(2):191-8. http://doi.org/10.1016/0739-7240(90)90025-U. PMid:2114957.

Armstrong JD, Kraeling R, Britt J. Effects of naloxone or transient weaning on secretion of LH and prolactin in lactating sows. J Reprod Fertil. 1988;83(1):301-8. http://doi.org/10.1530/jrf.0.0830301. PMid:3397944.

Armstrong TA, Flowers WL, Britt JH. Control of the weaning-to-estrus interval in sows using gonadotropins and prostaglandins during lactation. J Anim Sci. 1999;77(9):2533-9. http://doi.org/10.2527/1999.7792533x. PMid:10492462.

Barb CR, Chang WJ, Leshin LS, Rampacek GB, Kraeling RR. Opioid modulation of gonadotropin releasing hormone release from the hypothalamic preoptic area in the pig. Domest Anim Endocrinol. 1994;11(4):375-82. http://doi.org/10.1016/0739-7240(94)90009-4. PMid:7828431.

Barb CR, Kraeling RR, Rampacek GB, Scott Whisnant C. Opioid inhibition of luteinizing hormone secretion in the postpartum lactating sow. Biol Reprod. 1986;35(2):368-71. http://doi.org/10.1095/biolreprod35.2.368. PMid:3533168.

Basini G, Baioni L, Bussolati S, Grolli S, Grasselli F. Prolactin is a potential physiological modulator of swine ovarian follicle function. Regul Pept. 2014;189:22-30. http://doi.org/10.1016/j.regpep.2014.01.003. PMid:24530842.

Bogacka I, Siawrys G, Okrasa S, Kaminski T, Przala J. The influence of GnRH, oxitocin and vasoactive intestinal peptide on LH and PRL secretion by porcine pituitary cells in vitro. J Physiol Pharmacol. 2002;53(3):439-51. PMid:12369740.

Bown P. Advantages and disadvantages of batch farrowing. In Pract. 2006;28(2):94-6. http://doi.org/10.1136/inpract.28.2.94.

Britt JH. Improving sow productivity through management during gestation, lactation and after weaning. J Anim Sci. 1986;63(4):1288-96. http://doi.org/10.2527/jas1986.6341288x. PMid:3771407.

Campbell RK. Molecular pharmacology of gonadotropins. Endocrine. 2005;26(3):291-6. http://doi.org/10.1385/ENDO:26:3:291. PMid:16034184.

Cole HH, Hughes EH. Induction of estrus in lactating sows with equine gonadotropin. J Anim Sci. 1946;5(1):25-9. http://doi.org/10.2527/jas1946.5125. PMid:21015591.

Cole LA. Biological functions of hCG and hCG-related molecules. Reprod Biol Endocrinol. 2010;8:102. http://doi.org/10.1186/1477-7827-8-102. PMid:20735820.

Corezzolla JL, Ulguim RR, Gasperin BG, Rauber LP, Bianchi I. Altrenogest treatment effects on the reproductive performance of sows during transition to batch farrowing. Ciênc Rural. 2020;50(9):e20190806. https://doi.org/10.1590/0103-8478cr20190806.

Costermans NG, Soede NM, Middelkoop A, Laurenssen BF, Koopmanschap RE, Zak L, Knol EF, Keijer J, Teerds KJ, Kemp B. Influence of the metabolic state during lactation on milk production in modern sows. Animal. 2020a;14(12):2543-53. http://doi.org/10.1017/S1751731120001536. PMid:32580816.

Costermans NG, Soede NM, van Tricht F, Blokland M, Kemp B, Keijer J, Teerds KJ. Follicular fluid steroid profile in sows: relationship to follicle size and oocyte quality. Biol Reprod. 2020b;102(3):740-9. http://doi.org/10.1093/biolre/ioz217. PMid:31786607.

Costermans NG, Teerds KJ, Middelkoop A, Roelen BA, Schoevers EJ, van Tol HT, Laurenssen B, Koopmanschap RE, Zhao Y, Blokland M, van Tricht F, Zak L, Keijer J, Kemp B, Soede NM. Consequences of negative energy balance on follicular development and oocyte quality in primiparous sows. Biol Reprod. 2020c;102(2):388-98. http://doi.org/10.1093/biolre/ioz175. PMid:31504218.

Crighton D. The induction of pregnancy during lactation in the sow: the effects of a treatment imposed at 21 days of lactation. Anim Sci. 1970;12(4):611-7. http://doi.org/10.1017/S0003356100029251.

De Rensis F, Hunter MG, Foxcroft G. Suckling-induced inhibition of luteinizing hormone secretion and follicular development in the early postpartum sow. Biol Reprod. 1993;48(5):964-9. http://doi.org/10.1095/biolreprod48.5.964. PMid:8481483.

De Rensis F, Kirkwood R. Control of estrus and ovulation: fertility to timed insemination of gilts and sows. Theriogenology. 2016;86(6):1460-6. http://doi.org/10.1016/j.theriogenology.2016.04.089. PMid:27287469.

De Rensis F, Quintavalla F, Foxcroft G. Treatment of lactating sows with the dopamine agonist Cabergoline: effects on LH and prolactin secretion and responses to challenges with naloxone and morphine. Anim Reprod Sci. 1998;51(3):233-47. http://doi.org/10.1016/S0378-4320(98)00066-9. PMid:9675405.

Dial G, Marsh W, Polso nD, Vaillancourt JP. Reproductive failure: differential diagnosis. In: Leman AD, Straw BE, Mengeling WL, D’Allaire S, Taylor DJ, editors. Diseases of swine. 7th ed. Ames: Iowa State University Press; 1992. pp. 88-137.

Diaz FJ, Wiltbank MC. Acquisition of luteolytic capacity involves differential regulation by prostaglandin F2α of genes involved in progesterone biosynthesis in the porcine corpus luteum. Domest Anim Endocrinol. 2005;28(2):172-89. http://doi.org/10.1016/j.domaniend.2004.08.002. PMid:15713365.

Driancourt MA, Locatelli A, Prunier A. Effects of gonadotrophin deprivation on follicular growth in gilts. Reprod Nutr Dev. 1995;35(6):663-73. http://doi.org/10.1051/rnd:19950606. PMid:8534360.

Estill CT. Current concepts in estrus synchronization in swine. J Anim Sci. 2000;77(Suppl E):1-9. http://doi.org/10.2527/jas2000.77E-Suppl1m.

European Union. L 262, 14/10/2003. Directive 2003/74/EC of the European Parliament and of the Council on 22 September 2003 amending Council Directive 96/22/EC concerning the prohibition on the use in stockfarming of certain substances having a hormonal or thyristatic action and of beta-agonist. Official Journal of the European Union; Brussels; 2003 [cited 2023 Aug 6]. Available from: https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2003:262:0017:0021:EN:PDF

Ezcurra D, Humaidan P. A review of luteinising hormone and human chorionic gonadotropin when used in assisted reproductive technology. Reprod Biol Endocrinol. 2014;12:95. http://doi.org/10.1186/1477-7827-12-95. PMid:25280580.

Faccin JEG, Laskoski F, Hernig LF, Kummer R, Lima GFR, Orlando UAD, Gonçalves MAD, Mellagi APG, Ulguim RR, Bortolozzo FP. Impact of increasing weaning age on pig performance and belly nosing prevalence in a commercial multisite production system. J Anim Sci. 2020;98(4):skaa031. http://doi.org/10.1093/jas/skaa031. PMid:32034395.

Fiúza ATL, De Conti ER, Walter MP, Quirino M, Dos Santos JT, da Rosa Ulguim R, Wentz I, Mellagi APG, Bernardi ML, Bortolozzo FP. Intravaginal devices impregnated with medroxyprogesterone acetate avoid early parturition and synchronize farrowing in sows. Theriogenology. 2023;195:192-8. http://doi.org/10.1016/j.theriogenology.2022.10.029. PMid:36335723.

Food and Drug Administration - FDA. Steroid hormone implants used for growth in food-producing animals. Rome: FDA; 2021 [cited 2023 Aug 6]. Available from: https://www.fda.gov/animal-veterinary/product-safety-information/fda-provides-list-currently-approved-and-currently-marketed-implants-available-beef-cattle-target

Freling GF, Gasperin BG, Ferreira R, Cesaro MP, Oliveira JF, Bordignon V, Gonçalves PBD. Delaying farrowing using intravaginal devices impregnated with progestagen does not affect the proportion of piglets born alive. Cienc Rural. 2013;43(7):1258-64. http://doi.org/10.1590/S0103-84782013005000077.

Fuentes-Hernández VO, Bernal-Canseco A, Castro MLF, Hernández JRO. The effect of naloxone on reproductive behavior and plasma prolactin levels after weaning in third lactation sows. Rev Cient (Maracaibo). 2011;21(4):293-7.

Gasperin BG, Freling GF, Ferreira R, Oliveira JFC, Bordignon V, Gonçalves PBD. Intravaginal progestagen for estrus and parturition control in sows. Pesq Agropec Bras. 2011;46(8):961-4. https://doi.org/10.1590/S0100-204X2011000800024.

Gianluppi RDF, Lucca MS, Quirino M, Mellagi APG, Ulguim RR, Bortolozzo FP. Altrenogest treatment during the last week of lactation on ovarian traits and subsequent reproductive performance of primiparous and multiparous sows. Theriogenology. 2021;176:122-7. http://doi.org/10.1016/j.theriogenology.2021.09.027. PMid:34601236.

Haas CS, Santos MQ, Rovani MT, Santos JT, Mellagi APG, Bortolozzo FP, Gasperin BG, Gonçalves PBD. Prepartum progestagen supplementation in swine: a strategy to facilitate piglet care and prevent early parturition. Ciência Rural. 2017;47(11):e20170380. https://doi.org/10.1590/0103-8478cr20170380.

Hallast P, Saarela J, Palotie A, Laan M. High divergence in primate-specific duplicated regions: human and chimpanzee chorionic gonadotropin beta genes. BMC Evol Biol. 2008;8:195. http://doi.org/10.1186/1471-2148-8-195. PMid:18606016.

Hansen AV, Strathe AB, Kebreab E, France J, Theil PK. Predicting milk yield and composition in lactating sows: a Bayesian approach. J Anim Sci. 2012;90(7):2285-98. http://doi.org/10.2527/jas.2011-4788. PMid:22307478.

Hausler C, Hodson H Jr, Kuo D, Kinney T, Rauwolf V, Strack L. Induced ovulation and conception in lactating sows. J Anim Sci. 1980;50(5):773-8. http://doi.org/10.2527/jas1980.505773x. PMid:7390937.

Henke A, Gromoll J. New insights into the evolution of chorionic gonadotrophin. Mol Cell Endocrinol. 2008;291(1-2):11-9. http://doi.org/10.1016/j.mce.2008.05.009. PMid:18599193.

Hidalgo DM, Friendship RM, Greiner L, Manjarin R, Amezcua MR, Dominguez JC, Kirkwood RN. Influence of lactation length and gonadotrophins administered at weaning on fertility of primiparous sows. Anim Reprod Sci. 2014;149(3-4):245-8. http://doi.org/10.1016/j.anireprosci.2014.06.034. PMid:25064560.

Hodson H Jr, Hausler C, Snyder D, Wilkens M, Arthur R. Effect of gonadotropin dose and postpartum status on induced ovulation and pregnancy in lactating sows. J Anim Sci. 1981;52(4):688-95. http://doi.org/10.2527/jas1981.524688x. PMid:7263533.

Hoving LL, Soede NM, Feitsma H, Kemp B. Lactation weight loss in primiparous sows: consequences for embryo survival and progesterone and relations with metabolic profiles. Reprod Domest Anim. 2012;47(6):1009-16. http://doi.org/10.1111/j.1439-0531.2012.02007.x. PMid:22420822.

Innamma N, Roongsitthichai A. Reproductive effects of PG600 in female pigs. Wetchasan Sattawaphaet. 2015;45(4):493-8. http://doi.org/10.56808/2985-1130.2678.

Karg H, Vogt K. Control of hormone treatment in animals and residues in meat: regulatory aspects and approaches in methodology. J Assoc Off Anal Chem. 1978;61(5):1201-8. http://doi.org/10.1093/jaoac/61.5.1201. PMid:721733.

Kemp B, Da Silva CL, Soede NM. Recent advances in pig reproduction: focus on impact of genetic selection for female fertility. Reprod Domest Anim. 2018;53(Suppl 2):28-36. http://doi.org/10.1111/rda.13264. PMid:30238653.

Kim SW, Gormley A, Jang KB, Duarte ME. Current status of global pig production: an overview and research trends. Anim. Biosci. 2024;37(4):719-29. http://doi.org/10.5713/ab.23.0367. PMid:37946421.

Kirkwood RN, Henry SC, Tokach LM, Foxcroft GR. Human chorionic gonadotropin at parturition fails to consistently induce ovulation in sows. J Swine Health Prod. 1999;7:69-72.

Kirkwood RN, Thacker PA. Induced estrus and breeding during lactation: effects on sow and litter performance. J Swine Health Prod. 1998;6(3):95-8.

Knox RV. Artificial insemination in pigs today. Theriogenology. 2016;85(1):83-93. http://doi.org/10.1016/j.theriogenology.2015.07.009. PMid:26253434.

Knox RV. Recent advancements in the hormonal stimulation of ovulation in swine. Vet Med Res Rep. 2015;(3):309-20. http://doi.org/10.2147/VMRR.S68960. PMid:30101116.

Lane EA, Austin EJ, Crowe MA. Oestrous synchronisation in cattle - Current options following the EU regulations restricting use of oestrogenic compounds in food-producing animals: a review. Anim Reprod Sci. 2008;109(1-4):1-16. http://doi.org/10.1016/j.anireprosci.2008.08.009. PMid:18786787.

Levis DG. Effect of early weaning on sow reproductive performance - A review. Nebraska Swine Reports. V. 204. Lincoln: Animal Science Department, University of Nebraska - Lincoln; 1997.

Lopes TP, Bolarín A, Martínez EA, Roca J. Altrenogest treatment before weaning improves litter size in sows. Reprod Domest Anim. 2017;52(Suppl 4):75-7. http://doi.org/10.1111/rda.13063. PMid:29052320.

Lopes TP, Padilla L, Bolarin A, Rodriguez-Martinez H, Roca J. Ovarian follicle growth during lactation determines the reproductive performance of weaned sows. Animals (Basel). 2020;10(6):1012. http://doi.org/10.3390/ani10061012. PMid:32532102.

López-Vergé S, Gasa J, Coma J, Bonet J, Solà-Oriol D. Effect of lactation length caused by the management production system on piglet performance until slaughter. Livest Sci. 2019;224:26-30. http://doi.org/10.1016/j.livsci.2019.04.003.

Lucy MC, Liu J, Boyd CK, Bracken CJ. Ovarian follicular growth in sows. Reprod Suppl. 2001;58:31-45. http://doi.org/10.1530/biosciprocs.16.0003. PMid:11980199.

Lucy MC. Functional differences in the growth hormone and insulin‐like growth factor axis in cattle and pigs: implications for post‐partum nutrition and reproduction. Reprod Domest Anim. 2008;43(Suppl 2):31-9. http://doi.org/10.1111/j.1439-0531.2008.01140.x. PMid:18638098.

MacLeod M, Gerber P, Mottet A, Tempio G, Falcucci A, Opio C, Vellinga T, Henderson B, Steinfeld H. Greenhouse gas emissions from pig and chicken supply chains – A global life cycle assessment. Rome: Food and Agriculture Organization of the United Nations (FAO); 2013 [cited 2024 Apr 2]. Available from: https://www.fao.org/3/i3460e/i3460e00.htm

Martinat-Botte F. Induction of gestation during lactation in the sow. In: Proceedings of Biologie Animale Biochimie Biophysique; 1975; Les Ulis. Les Ulis: EDP Sciences; 1975. pp. 369-74.

Meile A, Nathues H, Kauffold J, Grahofer A. Ultrasonographic examination of postpartum uterine involution in sows. Anim Reprod Sci. 2020;219:106540. http://doi.org/10.1016/j.anireprosci.2020.106540. PMid:32828414.

Ming D, Wang W, Huang C, Wang Z, Shi C, Ding J, Liu H, Wang F. Effects of weaning age at 21 and 28 days on growth performance, intestinal morphology and redox status in piglets. Animals (Basel). 2021;11(8):2169. http://doi.org/10.3390/ani11082169. PMid:34438627.

Murphy B. Equine chorionic gonadotropin: an enigmatic but essential tool. Anim Reprod. 2018;9(3):223-30.

Porter MB, Brumsted JR, Sites CK. Effect of prolactin on follicle-stimulating hormone receptor binding and progesterone production in cultured porcine granulosa cells. Fertil Steril. 2000;73(1):99-105. http://doi.org/10.1016/S0015-0282(99)00463-X. PMid:10632421.

Przygrodzka E, Lopinska M, Ziecik AJ. Precision-cut luteal slices: a promising approach for studying luteal function in pigs. Reprod Biol. 2014;14(3):243-7. http://doi.org/10.1016/j.repbio.2014.04.001. PMid:25152524.

Quesnel H. Nutritional and lactational effects on follicular development in the pig. Soc Reprod Fertil Suppl. 2009:66:121-34. PMid:19848276.

Quirino M, Pinheiro ARA, Santos JT, Ulguim RR, Mellagi APG, Bortolozzo FP. Reproductive performance of fixed-time artificial insemination in swine and factors for the technology success. Ciência Rural. 2019;49. https://doi.org/10.1590/0103-8478cr20180712.

Quirino M, Ulguim RR, Bernardi ML, Pereira VN, Magoga J, Gianluppi RDF, Mellagi APG, Gasperin BG, Bortolozzo FP. Follicular dynamic and reproductive performance of gilts submitted to estrous cycle synchronization using two different progestogen sources. Theriogenology. 2020;158:31-8. http://doi.org/10.1016/j.theriogenology.2020.08.035. PMid:32927198.

Rabelo S, Faria B, Rocha L, Pereira B, Chaves B, Pontelo T, Pereira L, Zangeronimo M. Incidence of the second parity syndrome in sows from a commercial farm. Arq Bras Med Vet Zootec. 2016;68(4):1085-9. http://doi.org/10.1590/1678-4162-8651.

Schams D, Kraetzl W-D, Brem G, Graf F. Secretory pattern of metabolic hormones in the lactating sow. Exp Clin Endocrinol. 1994;102(6):439-47. http://doi.org/10.1055/s-0029-1211316. PMid:7890020.

Segura Correa JC, Alzina-López A, Santos-Ricalde RH. Risk factors associated with the occurrence of the second-litter syndrome in sows in southeastern Mexico. ScientificWorldJournal. 2013;2013:969620. http://doi.org/10.1155/2013/969620. PMid:24288517.

Senger P. Pathways to pregnancy and parturition. 3rd ed. Redmond: Current Conceptions; 2012. p. 273-291.

Sesti LA, Britt JH. Secretion of gonadotropins and estimated releasable pools of gonadotropin-releasing hormone and gonadotropins during establishment of suckling-induced inhibition of gonadotropin secretion in the sow. Biol Reprod. 1994;50(5):1078-86. http://doi.org/10.1095/biolreprod50.5.1078. PMid:8025164.

Słomczyńska M, Gregoraszczuk E, Kochman K, Stoklosowa S. Prolactin binding analysis and immunohistochemical localization of prolactin receptor in porcine ovarian cells. Endocr J. 2001;48(1):71-80. http://doi.org/10.1507/endocrj.48.71. PMid:11403105.

Terry R, Kind K, Lines D, Kennett T, Hughes P, van Wettere W. Lactation estrus induction in multi-and primiparous sows in an Australian commercial pork production system. J Anim Sci. 2014;92(5):2265-74. http://doi.org/10.2527/jas.2013-7475. PMid:24663189.

Ulguim RR, Mallmann AL, Gasperin BG, Bernardi ML, Wentz I, Mellagi APG, Bortolozzo FP. Effects of intravaginal devices containing different dosages of medroxyprogesterone acetate for the control of the estrous cycle in gilts. Anim Reprod Sci. 2019;210:106200. http://doi.org/10.1016/j.anireprosci.2019.106200. PMid:31635772.

Valros A, Rundgren M, Špinka M, Saloniemi H, Hultén F, Uvnäs-Moberg K, Tománek M, Krejcı P, Algers B. Oxytocin, prolactin and somatostatin in lactating sows: associations with mobilisation of body resources and maternal behaviour. Livest Prod Sci. 2004;85(1):3-13. http://doi.org/10.1016/S0301-6226(03)00114-3.

Valros AE, Rundgren M, Špinka M, Saloniemi H, Rydhmer L, Algers B. Nursing behaviour of sows during 5 weeks lactation and effects on piglet growth. Appl Anim Behav Sci. 2002;76(2):93-104. http://doi.org/10.1016/S0168-1591(02)00006-0.

Van den Brand H, Dieleman SJ, Soede NM, Kemp B. Dietary energy source at two feeding levels during lactation of primiparous sows: I. Effects on glucose, insulin, and luteinizing hormone and on follicle development, weaning-to-estrus interval, and ovulation rate. J Anim Sci. 2000;78(2):396-404. http://doi.org/10.2527/2000.782396x. PMid:10709931.

Van Wettere W, Kaisler-Smith C, Terry R, Weaver A, Herde P, Kennaway D, Hughes P, Kind K. Boar contact is an effective stimulant of ovulation during early lactation. Livest Sci. 2013;155(2-3):454-8. http://doi.org/10.1016/j.livsci.2013.04.017.

Van Wettere WH, Weaver AC, Greenwood EC, Terry R, Hughes PE, Kind KL. Controlling lactation oestrus: the final frontier for breeding herd management. Mol Reprod Dev. 2017;84(9):883-96. http://doi.org/10.1002/mrd.22838. PMid:28628264.

Wood CM, Kornegay ET, Shipley CF. Efficacy of altrenogest in synchronizing estrus in two swine breeding programs and effects on subsequent reproductive performance of sows. J Anim Sci. 1992;70(5):1357-64. http://doi.org/10.2527/1992.7051357x. PMid:1526904.

Wylot B, Tworus K, Okrasa S. The effects of mu-, delta-and kappa-opioid receptor activation on luteinizing and folliclestimulating hormone secretion from porcine pituitary cells. J Physiol Pharmacol. 2013;64(4):505-11. PMid:24101398.

Yuan W, Lucy M. Messenger ribonucleic acid expression for growth hormone receptor, luteinizing hormone receptor, and steroidogenic enzymes during the estrous cycle and pregnancy in porcine and bovine corpora lutea. Domest Anim Endocrinol. 1996;13(5):431-44. http://doi.org/10.1016/0739-7240(96)00073-2. PMid:8886596.

Yun J, Swan K-M, Farmer C, Oliviero C, Peltoniemi O, Valros A. Prepartum nest-building has an impact on postpartum nursing performance and maternal behaviour in early lactating sows. Appl Anim Behav Sci. 2014;160:31-7. http://doi.org/10.1016/j.applanim.2014.08.011.

Zemitis J, Bouwman EG, Langendijk P, van Wettere W, Kirkwood R. Postpartum injection of human chorionic gonadotrophin: effects on sow ovarian follicles. J Swine Health Prod. 2015;23(3):137-9.

Ziecik AJ, Klos J, Gromadzka-Hliwa K, Dietrich MA, Slowinska M, Likszo P, Knapczyk-Stwora K, Gajewski Z, Kaczmarek MM. Endocrine and molecular milieus of ovarian follicles are diversely affected by human chorionic gonadotropin and gonadotropin-releasing hormone in prepubertal and mature gilts. Sci Rep. 2021;11(1):13465. http://doi.org/10.1038/s41598-021-91434-6. PMid:34188064.

Ziecik AJ, Przygrodzka E, Jalali BM, Kaczmarek MM. Regulation of the porcine corpus luteum during pregnancy. Reproduction. 2018;156(3):R57-67. http://doi.org/10.1530/REP-17-0662. PMid:29794023.
 


Submitted date:
08/10/2023

Accepted date:
05/27/2024

6695722da95395212f522413 animreprod Articles
Links & Downloads

Anim Reprod

Share this page
Page Sections