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García-Casillas AC, Prado-Rebolledo OF, Carrillo-Díaz MI, Zepeda-Batista JL, Barajas-Saucedo CE, Hernández-Rivera JA. Reproductive Activity of Socorro Island Merino Ewes and Their Crosses with Pelibuey under Heat Stress Conditions. Animals (Basel) 2024; 14:1405. [PMID: 38791623 PMCID: PMC11117342 DOI: 10.3390/ani14101405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 04/25/2024] [Accepted: 05/04/2024] [Indexed: 05/26/2024] Open
Abstract
An experiment was carried out to evaluate the effect of spring and autumn seasons on the reproductive activity of Merino Socorro Island ewes and their crosses with Pelibuey under heat stress (HS) conditions in the tropics. All ewes (n = 80) were randomly assigned to one of two breeds during the first and second periods, respectively: (1) Twenty Socorro Island Merino ewes (SIM) and (2) 20 Pelibuey Crossbred ewes (PBC). Animals were fed the same diet and given water ad libitum. All statistical analyses were performed using SAS statistical software 9.12 procedures. In both seasons, a mean of more than 80 U of maximum THI was obtained, while in spring and autumn, the minimum THI exceeded 30 and 40 U, respectively. All animals were in oestrus and ovulated in both seasons. The frequency of animals in spring during the first 48 h of oestrus expression was greater (p < 0.05) than 48-55 h but similar (p > 0.05) than 55-65 h; in autumn during the first 48 h and 48-55 h were similar (p > 0.05), but different (p < 0.05) than 55-65 h. The duration of oestrus expression was longer in the spring than in the autumn (p < 0.05). The frequency of animals was higher (p < 0.05) in SIM than in PBC ewes during the first oestrus cycle (1-17 d) and was also higher (p < 0.05) in PBC than in SIM ewes during the second oestrus cycle (18-35 d). The SIM ewes produced more (p < 0.05) progesterone (P4) than the PBC ewes. During the sampling days of the oestrus cycle, more P4 was created in autumn than in spring (p < 0.05). Both breeds showed severe HS. In the future, ewes treated under assisted reproductive programs in the tropics may improve reproductive efficiency.
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Affiliation(s)
- Arturo César García-Casillas
- Faculty of Veterinary Medicine and Animal Husbandry, University of Colima, Tecoman 28930, Colima, Mexico; (A.C.G.-C.); (O.F.P.-R.); (M.I.C.-D.); (J.L.Z.-B.)
| | - Omar Francisco Prado-Rebolledo
- Faculty of Veterinary Medicine and Animal Husbandry, University of Colima, Tecoman 28930, Colima, Mexico; (A.C.G.-C.); (O.F.P.-R.); (M.I.C.-D.); (J.L.Z.-B.)
| | - María Isabel Carrillo-Díaz
- Faculty of Veterinary Medicine and Animal Husbandry, University of Colima, Tecoman 28930, Colima, Mexico; (A.C.G.-C.); (O.F.P.-R.); (M.I.C.-D.); (J.L.Z.-B.)
| | - José Luis Zepeda-Batista
- Faculty of Veterinary Medicine and Animal Husbandry, University of Colima, Tecoman 28930, Colima, Mexico; (A.C.G.-C.); (O.F.P.-R.); (M.I.C.-D.); (J.L.Z.-B.)
| | | | - Juan Augusto Hernández-Rivera
- Faculty of Veterinary Medicine and Animal Husbandry, University of Colima, Tecoman 28930, Colima, Mexico; (A.C.G.-C.); (O.F.P.-R.); (M.I.C.-D.); (J.L.Z.-B.)
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McEvoy MJ, McAfee M, Hession JA, Creedon L. A Mathematical Model of Estradiol Production from Ultrasound Data for Bovine Ovarian Follicles. Cells 2022; 11:cells11233908. [PMID: 36497167 PMCID: PMC9739503 DOI: 10.3390/cells11233908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 10/29/2022] [Accepted: 11/03/2022] [Indexed: 12/12/2022] Open
Abstract
In this paper, we present a new way to assess the concentration of estradiol (E2) and Insulin Growth Factor-1 (IGF) based on the results from ultrasound scans combined with mathematical models. The IGF1 model is based on the progesterone (P4) concentration, which can be estimated with models calculating P4 level based on the size/volume of corpus luteum (CL) measured during ultrasound scans. At this moment little is known about the underlying reasons for double ovulation and silent heat occurrences. Both of these are linked to the level of IGF1: double ovulations are linked to higher IGF1 levels and and silent heat is linked to lower E2 to P4 ratio. These models can help to improve understanding of the related concentrations of E2 and IGF1. Currently, it is known that diet and genetic factors have an impact on ovulation rates and silent heat. In this study, we also examine the decline of the production of E2 in vivo by atretic follicles throughout the process of atresia. This is the first recorded quantitative description of this decline.
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Nosratpour S, Ndiaye K. Ankyrin-repeat and SOCS box-containing protein 9 (ASB9) regulates ovarian granulosa cells function and MAPK signaling. Mol Reprod Dev 2021; 88:830-843. [PMID: 34476862 DOI: 10.1002/mrd.23532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 08/03/2021] [Accepted: 08/24/2021] [Indexed: 11/05/2022]
Abstract
Ankyrin-repeat and SOCS box-containing proteins (ASB) interact with the elongin B-C adapter via their SOCS box domain and with the cullin and ring box proteins to form E3 ubiquitin ligase complexes within the protein ubiquitination pathway. ASB9 in particular is a differentially expressed gene in ovulatory follicles (OFs) induced by the luteinizing hormone (LH) surge or hCG injection in ovarian granulosa cells (GC) while downregulated in growing dominant follicles. Although ASB9 has been involved in biological processes such as protein modification, the signaling network associated with ASB9 in GC is yet to be fully defined. We previously identified and reported ASB9 interactions and binding partners in GC including PAR1, TAOK1, and TNFAIP6/TSG6. Here, we further investigate ASB9 effects on target binding partners regulation and signaling in GC. CRISPR/Cas9-induced inhibition of ASB9 revealed that ASB9 regulates PAR1, TAOK1, TNFAIP6 as well as genes associated with proliferation and cell cycle progression such as PCNA, CCND2, and CCNE2 while CCNA2 was not affected. Inhibition of ASB9 was also associated with increased GC number and decreased caspase3/7 activity, CASP3 expression, and BAX/BCL2 ratio. Furthermore, ASB9 induction in OF in vivo 24 h post-hCG is concomitant with a significant decrease in phosphorylation levels of MAPK3/1 while pMAPK3/1 levels increased following ASB9 inhibition in GC in vitro. Together, these results provide strong evidence for ASB9 as a regulator of GC activity and function by modulating MAPK signaling likely through specific binding partners such as PAR1, therefore controlling GC proliferation and contributing to GC differentiation into luteal cells.
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Affiliation(s)
- Soma Nosratpour
- Centre de Recherche en Reproduction et Fertilité (CRRF), Veterinary Biomedicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Kalidou Ndiaye
- Centre de Recherche en Reproduction et Fertilité (CRRF), Veterinary Biomedicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
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Paul V, Krishnan G, Deori S, Bam J, Chakravarty P, Sarkar M. Body status and blood metabolites profiles during resumption of postpartum ovarian activity in yak (Poephagus grunniens). Reprod Domest Anim 2021; 56:1377-1386. [PMID: 34378257 DOI: 10.1111/rda.14002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 08/09/2021] [Indexed: 11/28/2022]
Abstract
We examined the changes in body weight (BW), back-fat thickness (BFT) and blood metabolites in relation to postpartum (PP) ovarian activity status in twenty female yaks raised under semi-intensive system. BFT and ovarian activities, like follicle development, ovulation (OV) and corpus luteum (CL) development, were monitored from 4 to 15 weeks (wk) PP using ultrasonography. Resumption of ovarian activity was confirmed with ovulation of dominant follicle (DF) and subsequent CL development, and >1 ng/ml progesterone concentration in blood plasma sample after 1week of ovulation. Yaks were further classified as cyclic (with CL), acyclic (without CL), and cystic (with >25 mm follicular cyst; FC). Within 20 weeks PP, 60% yaks resumed cyclic ovarian activity, while 25% failed to initiate cycling activity, and 15% developed follicular cysts. In all categories of yak, BW gradually decreased (p < .05) till nadir; however, nadir reached earlier (p < .05) in acyclic yaks. BFT differed (p < .05) among the yak groups, but it tended to be higher in cyclic yaks as compared to acyclic and cystic. No difference (p > .05) in non-esterified fatty acids (NEFA) values was found among the different categories of yaks, whereas, beta-hydroxy butyrate (BHB) levels were higher in cystic animals as compared to acyclic and cyclic. Blood glucose levels decreased in all yaks during initial 2 weeks after calving. Our findings suggest that yaks with low BW, BFT and glucose levels, and higher BHB values were at risk of delayed resumption of ovarian activity and concomitant development of follicular cysts.
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Affiliation(s)
- Vijay Paul
- ICAR-National Research Centre on Yak, Arunachal Pradesh, India
| | - G Krishnan
- ICAR-National Research Centre on Yak, Arunachal Pradesh, India.,ICAR-National Institute of Animal Nutrition and Physiology, Bengaluru, India
| | - S Deori
- ICAR-National Research Centre on Yak, Arunachal Pradesh, India.,ICAR-Research Complex for NEH region, Meghalaya, India
| | - Joken Bam
- ICAR-National Research Centre on Yak, Arunachal Pradesh, India
| | - P Chakravarty
- ICAR-National Research Centre on Yak, Arunachal Pradesh, India
| | - M Sarkar
- ICAR-National Research Centre on Yak, Arunachal Pradesh, India
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Smulski S, Gehrke M, Libera K, Cieslak A, Huang H, Patra AK, Szumacher-Strabel M. Effects of various mastitis treatments on the reproductive performance of cows. BMC Vet Res 2020; 16:99. [PMID: 32228579 PMCID: PMC7106650 DOI: 10.1186/s12917-020-02305-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 03/04/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The purpose of the study described here was to evaluate the effects of different supportive treatments - such as antioxidants, immunomodulators, and nonsteroidal anti-inflammatory drugs (NSAIDs) - in mastitic cows treated with intramammary antibiotics on the efficacy of mastitis therapy and fertility indices. Fertility indices, including time to first insemination, conception rate, time between calving and conception (open days), and number of services per conception (insemination index), were evaluated for 300 dairy cows. Sixty cows without apparent clinical signs of mastitis were assigned 100 days after calving to a Control group. Another 240 cows with clinical mastitis were systematically divided into four experimental groups (I-IV) of 60 cows each. All mastitic cows were treated with approved intramammary antibiotics in recommended doses. Cows in Group I were treated with intramammary antibiotics only. Cows in Groups II, III, and IV, received intramammary antibiotic therapy and a single injection with antioxidants, an immunomodulator (lysozyme dimer), or an NSAID (flunixin meglumine), respectively. RESULTS The lowest treatment efficacy of mastitic quarters and cows was noted in Group I (51.6 and 53.3%; p > 0.05). The best recovery rate was noted in Group II (63.3 and 66.7%; p > 0.05), followed by Group III (58.3 and 60.9%) and Group IV (58.3 and 58.0%; p > 0.05). The above data did not differ statistically (p > 0.05). The animals with mastitis (Groups I-IV) showed prolonged time to first insemination, more open days, higher insemination index, and lower conception rate than the control cows (p < 0.05). The conception rate of healthy cows and of successfully treated cows was insignificantly lower than that of cows required prolonged antibiotic therapy. Supportive treatments improved the mastitis recovery rate compared with intramammary antibiotics only. The efficacy of mastitis treatments affected the reproduction indices: in cows requiring prolonged treatment with antioxidants, a shorter time to first insemination was needed than in other groups (p < 0.05). Fewer days open were observed between the group with antioxidants and the control group (p < 0.05). CONCLUSIONS Clinical mastitis negatively affects reproductive indices (days open, pregnancy rate after first AI, NSC) in dairy cows. Different types of supportive medicine, such as antioxidants (vitamin C and E, and β-carotene), lysozyme dimer, or NSAID can be useful in improving fertility in mastitis cows treated with antibiotic only. It has been proven that each supportive treatment improved antibiotics efficiency and the antibiotic combined with the antioxidants was the most effective treatment.
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Affiliation(s)
- Sebastian Smulski
- Department of Internal Diseases and Diagnosis, Faculty of Veterinary Medicine and Animal Science, Poznań University of Life Sciences, Poznań, Poland
| | - Marek Gehrke
- Veterinary Centre, Nicolaus Copernicus University, Torun, Poland
| | - Kacper Libera
- Department of Preclinical Sciences and Infectious Diseases, Faculty of Veterinary Medicine and Animal Science, Poznań University of Life Sciences, Wolynska 35, 60-637, Poznan, Poland.
| | - Adam Cieslak
- Department of Animal Nutrition, Faculty of Veterinary Medicine and Animal Science, Poznań University of Life Sciences, Poznań, Poland
| | - Haihao Huang
- Department of Animal Nutrition, Faculty of Veterinary Medicine and Animal Science, Poznań University of Life Sciences, Poznań, Poland
| | - Amlan Kumar Patra
- Department of Animal Nutrition, West Bengal University of Animal and Fishery Sciences, Kolkata, India
| | - Malgorzata Szumacher-Strabel
- Department of Animal Nutrition, Faculty of Veterinary Medicine and Animal Science, Poznań University of Life Sciences, Poznań, Poland
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Uterine hemodynamics during a short-term progesterone synchronization protocol in ewes. Trop Anim Health Prod 2019; 52:503-509. [PMID: 31392554 DOI: 10.1007/s11250-019-02035-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/29/2019] [Indexed: 10/26/2022]
Abstract
Twenty-eight pluriparous and non-lactating Santa Inês sheep were synchronized with vaginal sponge and an intramuscular (IM) injection of 37.5 μg of cloprostenol on random days of the estrous cycle (D0); day 6 (D6), at 7:00 am, the devices were removed, and after 24 h (D7), GnRH analog (25 μg of lecirelin) was administrated. Fixed-time artificial insemination (FTAI) with cervical traction by the transcervical route was performed 52 to 58 h after sponge removal. Doppler velocimetry of both uterine arteries was performed on D0, D2, D4, and the morning of D6 (every 48 h), and then every 12 h from D6 to D8 (7:00 a.m. and 7:00 p.m.). We analyzed the peak systolic velocity (PSV), end-diastolic velocity (EVD), time-averaged maximum and mean velocity (TAMAX, TAMEAN), pulsatility index (PI), resistance index (RI), systolic/diastolic ratio (S/D), arterial diameter (AD), and blood flow volume (BFV), with the objective of evaluating the hemodynamic behavior of blood flow velocity parameters of the uterine artery during a short-term progesterone synchronization protocol in ewes. With respect to phases, we noted increases in the means of TAMAX and TAMEAN and decreases of EDV, PI, and RI (P < 0.05). S/D, EDV, TAMEAN, PI, RI, SD, AD, and BFV showed differences between the time of progesterone insertion and the estimated time of ovulation (which was considered the last evaluation) (P < 0.05). The PI and RI values were different when comparing the times of insertion and withdrawal of the progesterone device (PI 2.53-1.54 and RI 0.76-0.68) (P < 0.05). The PI was different with respect to side (P < 0.001), but no side effect was seen in the RI. In conclusion, the two uterine arteries behave differently under the effect of progesterone (intravaginal sponges) and the effect of estradiol during the follicular phase, and estrous phase was responsible for increasing uterine blood flow.
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Effect of breed and other animal-related factors on conception rate to artificial insemination with frozen semen in mares in Ethiopia. Trop Anim Health Prod 2019; 51:1173-1178. [PMID: 30659458 DOI: 10.1007/s11250-019-01804-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 01/06/2019] [Indexed: 10/27/2022]
Abstract
Equine reproduction is unique by having long behavioral estrus and differences in time of breeding between breeds and individuals of mares. An experimental study was conducted at the Balderas Sport Horses and Recreational Center, Addis Ababa, Ethiopia, from January to June, 2018, to evaluate conception rate to frozen semen in local and exotic crossbreed mares. Mares were teased to characterize estrus behavior and examined by ultrasound in determining imminent ovulation. Inseminations were done post ovulation within an average of 6-9 h using frozen-thawed semen. The overall conception rate to frozen semen was 15/21 (71.43%) with 8/11 (72.73%) in crossbreed and 7/10 (70%) in local breed mares. Age and body condition score (BCS) of animals had no significant effect on conception rate to AI with frozen semen. A slightly higher conception rate was obtained when ovulation was from the right ovary than when ovulated from the left ovary. A higher conception rate was obtained when the diameter of the preovulatory follicle was ≤ 45 mm than above diameter. The conception rate increased significantly with increased number of services/conception with an overall mean ± (SEM) of 2.2 ± 0.2 services/conception. A more number of services/conception were required for local breed (2.7 ± 0.2) than crossbreed mares (1.8 ± 0.3) and again for lower body condition scores than higher condition scores of mares. In conclusion, the increased number of services improved the conception rate with significant difference between breed of mares, whereas good management of mares for improved body conditions could be required to decrease the number of services per conception.
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Are female camels capital breeders? Influence of seasons, age, and body condition on reproduction in an extremely arid region. Mamm Biol 2018. [DOI: 10.1016/j.mambio.2018.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Smith MF, Geisert RD, Parrish JJ. Reproduction in domestic ruminants during the past 50 yr: discovery to application. J Anim Sci 2018; 96:2952-2970. [PMID: 29684167 PMCID: PMC6095338 DOI: 10.1093/jas/sky139] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 04/18/2018] [Indexed: 12/18/2022] Open
Abstract
The study of reproductive physiology in domestic ruminants has progressed from the whole animal to the molecular level in an amazingly short period of time. The volume of information on this subject is enormous; therefore, we have focused on domestic ruminants, with an emphasis on cattle. To date, artificial insemination (AI) is perhaps the most powerful technique that reproductive physiologists and geneticists have provided the livestock industry for genetic improvement. Early efforts to establish AI as a tool were initiated in Russia around 1899 and since that time major advances in methods of semen collection, evaluation of male fertility, cryopreservation of sperm, sex-sorted semen, and estrous cycle control have occurred. The preceding advances not only led to the widespread use of AI, but also contributed to our fundamental understanding of ovulation control, timing of insemination, gamete biology, and cryopreservation. In regards to anestrus, our understanding of the concept of neuroendocrine control of the pituitary gland and the role of steroid feedback led to the Gonadostat Theory, which proposes that onset of puberty is due to a decrease in the negative feedback of gonadal steroids over time. Subsequent studies in prepuberal and postpartum sheep and cattle established that a short luteal phase frequently precedes the first normal length cycle that is accompanied by estrous expression. This observation led to the common practice of treating prepuberal heifers and anestrous postpartum cows with a short-term progestin treatment (e.g., Controlled Internal Drug Release) to induce normal estrous cycles. In domestic ruminants, fertilization rate is high (85% to 95%); however, significant embryonic mortality before or around the time of maternal recognition of pregnancy (MRP) reduces the pregnancy rate to a single breeding. Significant effort has been directed at determining the time of MRP, the signal for MRP, as well as elucidating the physiological, cellular, and molecular dialogue between the conceptus and uterine environment. Advancements have now led us to the ability to edit the genome to alleviate disease and possibly improve production traits. In summary, major advancements in our understanding of reproductive biology have stemmed from efforts to establish the AI and embryo transfer technique and reduce the negative impact of anestrus and embryonic mortality in domestic ruminants.
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Affiliation(s)
- Michael F Smith
- Division of Animal Science, University of Missouri, Columbia, MO
| | - Rodney D Geisert
- Division of Animal Science, University of Missouri, Columbia, MO
| | - John J Parrish
- Department of Animal Science, University of Wisconsin, Madison, WI
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Beck K, Singh J, Dar MA, Anzar M. Short-term culture of adult bovine ovarian tissues: chorioallantoic membrane (CAM) vs. traditional in vitro culture systems. Reprod Biol Endocrinol 2018; 16:21. [PMID: 29523152 PMCID: PMC5845211 DOI: 10.1186/s12958-018-0337-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 02/28/2018] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND A suitable culture system is important for follicle growth in adult bovine ovarian tissue. This study aimed to assess the avian chorioallantoic membrane (CAM) for short-term culture of adult bovine ovarian tissues compared with a traditional in vitro culture system. METHODS Ovarian cortical tissues (1-2 mm3), collected from slaughtered adult cows, were randomly assigned to control, CAM or in vitro culture groups. In the control group, ovarian tissues were fixed with paraformaldehyde without culture. In CAM and in vitro culture groups, the ovarian tissues were cultured for up to 5 days and then fixed. Ovarian tissues were examined on culture days 0, 1, 3 and 5 for angiogenesis, follicle morphology and growth. In all groups, primordial and growing (healthy and atretic) follicle densities were determined. RESULTS In the CAM culture, the avian blood vessel density increased (p < 0.01) over time with a decline (p < 0.001) in the bovine blood vessel density. Healthy primordial, atretic primordial and healthy growing follicle densities were higher (p < 0.05) in CAM-cultured ovarian tissues than in vitro-cultured tissues. Regardless of the culture system, the density of healthy primordial follicles decreased (p < 0.001) over time with an increase in healthy growing follicles on day 3 (p < 0.01) and an increase in atretic (primordial and growing) follicles during the 5-day culture period (p < 0.001). The proportions of healthy primordial and atretic growing follicles were also affected by culture day (p < 0.001). CONCLUSIONS The CAM culture in chick embryos supported the bovine ovarian tissue grafts for 3 days demonstrating that CAM can be used as a satisfactory short-term culture system to assess ovarian tissue health, and to study follicle activation and development.
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Affiliation(s)
- Kylie Beck
- Agriculture and Agri-Food Canada, Saskatoon Research and Development Center, Canadian Animal Genetic Resource Program, S7N OX2, Saskatoon, SK Canada
- Departmnet of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4 Canada
| | - Jaswant Singh
- Departmnet of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4 Canada
| | - Mohammad Arshud Dar
- Vaccination and Infectious Disease Organization, University Saskatchewan, Saskatoon, S7N 5E3 Canada
| | - Muhammad Anzar
- Agriculture and Agri-Food Canada, Saskatoon Research and Development Center, Canadian Animal Genetic Resource Program, S7N OX2, Saskatoon, SK Canada
- Departmnet of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4 Canada
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Ballantyne K, Anderson ST, Pyne M, Nicolson V, Mucci A, Lisle A, Johnston SD. Use of the gonadotrophin-releasing hormone antagonist azaline B to control the oestrous cycle in the koala (Phascolarctos cinereus). Reprod Fertil Dev 2015; 28:RD14349. [PMID: 25929179 DOI: 10.1071/rd14349] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 03/25/2015] [Indexed: 02/28/2024] Open
Abstract
The present study examined the effectiveness of the gonadotrophin-releasing hormone (GnRH) antagonist azaline B to suppress plasma LH and 17β-oestradiol concentrations in koalas and its potential application for oestrous synchronisation. In Experiment 1, single subcutaneous injections of azaline B successfully blocked the LH response to exogenous mammalian (m) GnRH in a dose-dependent manner; specifically, 0 mg (n = 4) did not suppress the LH response, 1 mg azaline B (n = 6) suppressed the LH response for 24 h (P < 0.05), 3.3 mg azaline B (n = 8) suppressed the LH response significantly in all animals only for 3 h (P < 0.05), although in half the animals LH remained suppressed for up to 3 days, and 10 mg azaline B (n = 4) suppressed the LH response for 7 days (P < 0.05). In Experiment 2, daily 1 mg, s.c., injections of azaline B over a 10-day period during seasonal anoestrus (June-July; n = 6) suppressed (P < 0.01) the LH response to mGnRH consecutively over the 10-day treatment period and, 4 days after cessation of treatment, the LH response had not recovered. Experiment 3 was designed to test the efficacy of daily 1 mg, s.c., azaline B over 10 days to suppress plasma LH and 17β-oestradiol concentrations and ultimately synchronise timed return to oestrus during the breeding season. Although azaline B treatment did not suppress basal LH or 17β-oestradiol, oestrus was delayed in all treated females by 24.2 days, but with high variability (range 9-39 days). Overall, the present study demonstrates that the GnRH antagonist azaline B is able to inhibit the LH response in koalas to exogenous mGnRH and successfully delay the return to oestrus. However, although azaline B clearly disrupts folliculogenesis, it has not been able to effectively synchronise return to oestrus in the koala.
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Baddela VS, Baufeld A, Yenuganti VR, Vanselow J, Singh D. Suitable housekeeping genes for normalization of transcript abundance analysis by real-time RT-PCR in cultured bovine granulosa cells during hypoxia and differential cell plating density. Reprod Biol Endocrinol 2014; 12:118. [PMID: 25430436 PMCID: PMC4280684 DOI: 10.1186/1477-7827-12-118] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 11/19/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Bovine granulosa cell culture models are important to understand molecular mechanisms of ovarian function. Folliculogenesis and luteinization are associated with increasing density of cells and local hypoxic conditions. The current study identified two reliable housekeeping genes useful for gene normalization in granulosa cells under different in vitro conditions. METHODS During the current experiments cells were subjected to different biological and physical stimuli, follicle stimulating hormone, different initial cell plating density and hypoxia. Transcript abundance of seven housekeeping genes was quantified by real-time RT-PCR with co-amplification of the respective external standard. RESULTS Three of the genes, GAPDH, HMBS, and HPRT1 were found to be regulated by initial cell plating density, five of them, GAPDH, HMBS, HPRT1, RPLP0 and RPS18 under hypoxic conditions, but none of them after FSH stimulation. In detail, GAPDH was up regulated, but HPRT1 and HMBS were down regulated at high density and under hypoxia. Expression of RPLP0 and RPS18 was inconsistent, but was significantly down-regulated in particular at high cell density combined with hypoxia. In contrast, TBP and B2M genes were neither regulated under different plating density conditions nor by hypoxia as they showed similar expression levels under all conditions analyzed. CONCLUSIONS The present data indicate that TBP and B2M are appropriate housekeeping genes for normalization of transcript abundance measured by real-time RT-PCR in granulosa cells subjected to different plating densities, oxygen concentrations and FSH stimulation.
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Affiliation(s)
- Vijay S Baddela
- Animal Biochemistry Division, National Dairy Research Institute, Karnal, 132001 Haryana India
| | - Anja Baufeld
- Reproductive Biology, Leibniz Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Vengala R Yenuganti
- Reproductive Biology, Leibniz Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Jens Vanselow
- Reproductive Biology, Leibniz Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Dheer Singh
- Animal Biochemistry Division, National Dairy Research Institute, Karnal, 132001 Haryana India
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14
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Characterization of follicle and CL development in beef heifers using high resolution three-dimensional ultrasonography. Theriogenology 2014; 81:407-18. [DOI: 10.1016/j.theriogenology.2013.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 10/01/2013] [Accepted: 10/11/2013] [Indexed: 11/19/2022]
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15
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Naniwa Y, Nakatsukasa K, Setsuda S, Oishi S, Fujii N, Matsuda F, Uenoyama Y, Tsukamura H, Maeda KI, Ohkura S. Effects of full-length kisspeptin administration on follicular development in Japanese Black beef cows. J Reprod Dev 2013; 59:588-94. [PMID: 24107742 PMCID: PMC3934150 DOI: 10.1262/jrd.2013-064] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Kisspeptin is a key molecule that stimulates gonadotropin secretion via release of gonadotropin-releasing hormone (GnRH). In the present study, our aim was to investigate whether kisspeptin has stimulatory effects on follicular development via GnRH/gonadotropin secretion in cows. Japanese Black beef cows were intravenously injected with full-length bovine kisspeptin [Kp-53 (0.2 or 2 nmol/kg)] or vehicle 5 days after they exhibited standing estrus (Day 0). In cows injected with Kp-53 at 2 nmol/kg, the follicular sizes of the first dominant follicles increased on Day 6 and thereafter. Ovulation of the first dominant follicle occurred in 1 out of 4 cows treated with Kp-53 at 2 nmol/kg. Injection of Kp-53 at 2 nmol/kg increased the concentration of plasma luteinizing hormone (LH) but not follicle-stimulating hormone, over a 4-h period following injection in all cows. The present study suggests that administration of full-length kisspeptin causes LH secretion, which is sustained for a few hours, and it is capable of stimulating follicular development and/or ovulation.
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Affiliation(s)
- Yousuke Naniwa
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
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16
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Iber D, Geyter CD. Computational modelling of bovine ovarian follicle development. BMC SYSTEMS BIOLOGY 2013; 7:60. [PMID: 23856357 PMCID: PMC3726369 DOI: 10.1186/1752-0509-7-60] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Accepted: 07/11/2013] [Indexed: 11/23/2022]
Abstract
Background The development of ovarian follicles hinges on the timely exposure to the appropriate combination of hormones. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) are both produced in the pituitary gland and are transported via the blood circulation to the thecal layer surrounding the follicle. From there both hormones are transported into the follicle by diffusion. FSH-receptors are expressed mainly in the granulosa while LH-receptors are expressed in a gradient with highest expression in the theca. How this spatial organization is achieved is not known. Equally it is not understood whether LH and FSH trigger distinct signalling programs or whether the distinct spatial localization of their G-protein coupled receptors is sufficient to convey their distinct biological function. Results We have developed a data-based computational model of the spatio-temporal signalling processes within the follicle and (i) predict that FSH and LH form a gradient inside the follicle, (ii) show that the spatial distribution of FSH- and LH-receptors can arise from the well known regulatory interactions, and (iii) find that the differential activity of FSH and LH may well result from the distinct spatial localisation of their receptors, even when both receptors respond with the same intracellular signalling cascade to their ligand. Conclusion The model integrates the large amount of published data into a consistent framework that can now be used to better understand how observed defects translate into failed follicle maturation.
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Affiliation(s)
- Dagmar Iber
- Department for Biosystems Science and Engineering-D-BSSE, ETH Zurich, Swiss Institute of Bioinformatics, Basel, Switzerland.
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17
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Chasombat J, Nagai T, Parnpai R, Vongpralub T. Ovarian Follicular Dynamics, Ovarian Follicular Growth, Oocyte Yield, In vitro Embryo Production and Repeated Oocyte Pick Up in Thai Native Heifers Undergoing Superstimulation. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2013; 26:488-500. [PMID: 25049814 PMCID: PMC4093380 DOI: 10.5713/ajas.2012.12519] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 01/09/2013] [Accepted: 12/26/2012] [Indexed: 11/27/2022]
Abstract
The objective of this study was to compare the effectiveness of the protocols for superstimulation of follicular growth in Thai native heifers. Heifers (n = 20) were randomly divided into four groups of five heifers/group. Heifers were given a single dose by i.m. administration of 100 mg Follicle Stimulating Hormone dissolved in polyvinylpyrrolidone (FSHp) at 24 h. Ovum pick up (OPU) occurred at 72 h (F24O72 protocol; Group 1) or 96 h (F24O96 protocol; Group 2), and at 36 h and OPU at 72 h (F36O72 protocol; Group 3) or 96 h (F36O96 protocol; Group 4) after follicular ablation. The dynamics of ovarian follicular growth were monitored by twice-daily ultrasonographic examinations. Blood sample collections were performed every 12 h after initiation of treatment for assessment of FSH, E2 and P4 profiles. All heifers were subjected to eight repeated sequential sessions of OPU. The follicular deviation commenced 24±5.32 h after follicular ablation in all groups. The circulatory FSH surged quickly from 24 to 36 h (>0.8 ng/ml) after follicular ablation and circulatory estrogen levels steadily increased from 36 h until OPU in all groups. At the end of the OPU sessions, the mean number of aspirated follicles/heifer/session in F36O72 protocol (Group 3) and F36O96 protocol (Group 4) were higher than in the two other groups (p<0.05). The number of cumulus-oocyte complexes (COCs), cleaved and day 8 blastocysts rates in the F36O72 protocol (Group 3) were higher than in the other groups (p<0.05). It can be concluded that a single dose i.m. administration of 100 mg FSHp at 36 h and OPU at 72 h after follicular ablation (F36O72 protocol; Group 3) was the most effective protocol for superstimulation of follicular growth for repeated OPU and subsequent in vitro embryo production in Thai native heifers.
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Affiliation(s)
- J. Chasombat
- Department of Animal Science, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002,
Thailand
| | | | | | - T. Vongpralub
- Department of Animal Science, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002,
Thailand
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18
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Cummins S, Lonergan P, Evans A, Butler S. Genetic merit for fertility traits in Holstein cows: II. Ovarian follicular and corpus luteum dynamics, reproductive hormones, and estrus behavior. J Dairy Sci 2012; 95:3698-710. [DOI: 10.3168/jds.2011-4976] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 02/27/2012] [Indexed: 11/19/2022]
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19
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Walsh SW, Matthews D, Browne JA, Forde N, Crowe MA, Mihm M, Diskin M, Evans ACO. Acute dietary restriction in heifers alters expression of genes regulating exposure and response to gonadotrophins and IGF in dominant follicles. Anim Reprod Sci 2012; 133:43-51. [PMID: 22771244 DOI: 10.1016/j.anireprosci.2012.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 06/07/2012] [Accepted: 06/15/2012] [Indexed: 10/28/2022]
Abstract
Dietary restriction in growing cattle and severe negative energy balance in lactating cows have been associated with altered gonadotropin secretion, reduced follicle diameter, reduced circulating oestradiol concentrations and anovulation. Therefore, we hypothesised that acute dietary restriction would influence the fate and function of the dominant follicle by altering the expression for genes regulating gonadotrophin and IGF response in ovarian follicles. Newly selected dominant follicles were collected 7-8 days after prostaglandin F(2α) (PGF) administration from heifers (n=25) that were individually fed a diet supplying 1.2 maintenance (M; control, n=8) or 0.4 M (restricted, n=17) for a total duration of 18-19 days. Heifers within 0.4 M were ovulatory (n=11) or anovulatory (n=6) depending on whether the dominant follicle present at PGF ovulated or became atretic following luteolysis. Control animals were all ovulatory. Acute dietary restriction decreased IGF-I (P<0.001) and insulin (P<0.05) in circulation; oestradiol (P<0.01) and IGF-I (P<0.01) in follicular fluid; and mRNA for FSHR (P<0.01) in granulosa cells but increased mRNA for IGFBP2 (P<0.05) in theca cells of the newly selected dominant follicle. However, this only led to anovulation when dietary restriction also decreased mRNA for CYP19A1 (P<0.05), IGF2 (P<0.01) and IGF1R (P<0.05) in granulosa cells and LHCGR (P<0.05) in theca cells of follicles collected from heifers fed 0.4 M. These results suggest that the catabolic environment induced by dietary restriction may ultimately cause anovulation by reducing oestradiol synthesis, FSH-responsiveness and IGF signaling in granulosa, and LH-responsiveness in theca cells of dominant follicles.
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Affiliation(s)
- S W Walsh
- School of Agriculture and Food Science, University College Dublin, Belfield, Ireland
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20
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Cox JF, Allende R, Lara E, Leiva A, Díaz T, Dorado J, Saravia F. Follicular dynamics, interval to ovulation and fertility after AI in short-term progesterone and PGF2α oestrous synchronization protocol in sheep. Reprod Domest Anim 2012; 47:946-51. [PMID: 22471421 DOI: 10.1111/j.1439-0531.2012.01996.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The study was aimed to assess the influence that short-term progesterone treatments have on follicular dynamics, oestrus and ovulation in sheep. The treatment was tested thereafter in a field trial to assess its fertility after AI with fresh semen. In a first experiment, 12 ewes without CL were grouped to receive a new (n = 6) or used CIDR (n = 6) for 7 days and blood samples were obtained to follow plasma progesterone profiles. In a second experiment, 39 cycling ewes were synchronized by a 7-day P4+PGF2α protocol using a new (n = 20) or a 7-day used CIDR (n = 19). Half of both groups received 400 IU eCG and half remained untreated as controls. Ultrasound ovarian examination and oestrous detection were used to compare follicular dynamics, oestrus and ovulation in both groups. In a third experiment, 288 ewes in 3 farms were synchronized by the short-term P4+PGF2α+eCG protocol and ewes were AI with fresh semen 24 h after oestrous detection. Lambing performance was used to test the fertility of the treatment. In Experiment 1, ewes with new inserts presented higher P4 concentration than ewes with used inserts throughout the sampling period (p < 0.05) and exhibited a P4 peak at days 1-2 of the treatment that was not observed in ewes with used inserts. In Experiment 2, ewes treated with new and used inserts show similar ovarian and behavioral traits (p > 0.10). However, ewes treated with eCG show shorter interval to oestrus (p = 0.004) and tend to have larger mature CL (p = 0.06). In Experiment 3, oestrous presentation and lambing performance after AI with fresh semen was considered normal compared to published results. Results suggest that the oestrous synchronization protocol based on P4+PGF2α allows little control of follicular dynamics without compromising fertility after AI with fresh semen provided that eCG is added at the end of the treatment.
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Affiliation(s)
- J F Cox
- Department of Animal Sciences, Faculty of Veterinary Sciences, Universidad de Concepción, Chillán, Chile.
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21
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Ultrasonographic and endocrine aspects of follicle deviation, and acquisition of ovulatory capacity in buffalo (Bubalus bubalis) heifers. Anim Reprod Sci 2010; 123:175-9. [PMID: 21256685 DOI: 10.1016/j.anireprosci.2010.12.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 11/21/2010] [Accepted: 12/10/2010] [Indexed: 11/20/2022]
Abstract
The objectives of this study were to determine the interval from ovulation to deviation and the diameter of the dominant (DF) and largest subordinate (SF) follicles at deviation in buffalo (Bubalus bubalis) heifers. Two methods of evaluation (observed vs. calculated) were used. FSH and LH profiles encompassing follicle deviation (Experiment 1), and the follicular diameter when the DF acquired ovulatory capacity (Experiment 2) were also determined. The time of deviation and the diameter of the DF and the largest SF at deviation did not differ between observed and calculated methods. Overall, follicle deviation occurred 2.6 ± 0.2d (mean ± SEM) after ovulation, and the diameters of the DF and SF at deviation were 7.2 ± 0.2 and 6.4 ± 0.2mm, respectively. No changes in plasma levels of FSH or LH were observed (P=0.32 and P=0.96, respectively). Experiment 2 was conducted in two phases according to the diameter of the DF during the first wave of follicular development at the time of LH challenge (25mg of pLH). In the first phase, follicles ranging from 5.0 to 6.0mm (n=7), 6.1 to 7.0mm (n=11), or 7.1 to 8.0mm (n=9) were used, and in the second phase, follicles ranging from 7.0 to 8.4mm (n=10), 8.5 to 10.0mm (n=10), or 10.1 to 12.0mm (n=9) of diameter were used. After the pLH treatment, the DF was monitored by ultrasonography every 12h for 48h. No ovulations occurred in heifers in the first phase. However, in the second phase, an effect of follicular diameter was observed on ovulation rate [7.0-8.4mm (0.0%, 0/10), 8.5-10.0mm (50.0%, 5/10), and 10.0-12.0mm (55.6%, 5/9)]. In summary, follicle deviation occurred 2.6d after ovulation in buffalo (B. bubalis) heifers, when the diameters of the DF and SF were 7.2 and 6.4mm, respectively. No significant changes in plasma concentrations of FSH or LH were detected. Finally, the acquisition of ovulatory capacity occurred when the DF reached 8.5mm in diameter.
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Green J, Okamura C, Mathew D, Newsom E, Lucy M. Hot topic: Successful fixed-time insemination within 21 d after first insemination by combining chemical pregnancy diagnosis on d 18 with a rapid resynchronization program. J Dairy Sci 2010; 93:5668-72. [DOI: 10.3168/jds.2010-3395] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 09/20/2010] [Indexed: 11/19/2022]
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Abstract
The oestrous cycle in cattle lasts for 18-24 days. It consists of a luteal phase (14-18 days) and a follicular phase (4-6 days). During the cycle there are generally two (dairy cows) or three (heifers and beef cows) waves of ovarian follicle growth. Each wave of follicle growth consists of a period of emergence of a cohort of follicles, selection of a dominant follicle and either atresia or ovulation of the dominant follicle. These waves of follicle growth, initially established during the early pre-pubertal period of development occur throughout the entire cycle, with only the dominant follicle (DF) of the final wave coinciding with the follicular phase that undergoes final maturation and ovulation. Ovarian functions (follicle growth, ovulation, luteinisation and luteolysis) are regulated by the endocrine hormones of the hypothalamus (gonadotrophin-releasing hormone), anterior pituitary (follicle-stimulating hormone and luteinising hormone), ovaries (progesterone, oestradiol and inhibins) and the uterus (prostaglandin F2α). In postpartum cows resumption of regular oestrous cycles (in addition to uterine involution) is fundamental for re-establishment of pregnancy.
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24
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Green J, Okamura C, Poock S, Lucy M. Measurement of interferon-tau (IFN-τ) stimulated gene expression in blood leukocytes for pregnancy diagnosis within 18–20d after insemination in dairy cattle. Anim Reprod Sci 2010; 121:24-33. [DOI: 10.1016/j.anireprosci.2010.05.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 04/28/2010] [Accepted: 05/12/2010] [Indexed: 10/19/2022]
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25
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Peter A, Levine H, Drost M, Bergfelt D. Compilation of classical and contemporary terminology used to describe morphological aspects of ovarian dynamics in cattle. Theriogenology 2009; 71:1343-57. [DOI: 10.1016/j.theriogenology.2008.12.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 01/09/2009] [Accepted: 12/20/2008] [Indexed: 12/31/2022]
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26
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Small J, Colazo M, Kastelic J, Mapletoft R. Effects of progesterone presynchronization and eCG on pregnancy rates to GnRH-based, timed-AI in beef cattle. Theriogenology 2009; 71:698-706. [DOI: 10.1016/j.theriogenology.2008.09.045] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2008] [Revised: 06/12/2008] [Accepted: 09/12/2008] [Indexed: 11/30/2022]
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27
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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. [DOI: 10.1111/j.1439-0531.2008.01140.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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