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de Toledo RB, de Faria OAC, Leme LO, Magnabosco CU, Guimarães R, Eifert EDC, Dos Santos IR, Oliveira RV, Dode MAN, Malaquias JV, Pivato I, Martins CF. Effect of food supplementation on in vitro embryo production and growth performance in prepubertal Nelore heifers. Anim Biotechnol 2023; 34:5087-5096. [PMID: 37975200 DOI: 10.1080/10495398.2023.2279612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
In vitro embryos production from prepubertal heifers can help contribute to breeding programs; however, strategies are necessary to increase their embryo production. The aim of this study was to investigate the effects of two nutritional plans on oocyte recovery, embryo production and growth performance of prepubertal Nelore heifers. Thirty-four Nelore heifers with age of 6.5 months were divided into two feeding treatments (NP1 and NP2). The NP1 diets served as the control and NP2 diets were formulated to contain an average of 1.22-fold more energy than NP1. After 3 months of supplementation, the animals underwent follicular aspiration (ovum pick-up, OPU) every 21 d for 3 months and embryos were produced in vitro. Wither height, chest depth, body weight and subcutaneous fat of animals were measured. The number of retrieved and viable oocytes per OPU were 1.49-fold and 1.42-fold greater in NP2 heifers (p = 0.018 and p = 0.049, respectively) than those in NP1 heifers. Heifers administered NP2 produced 29.7% blastocysts, a percentage higher than NP1 animals that produced 24.40% embryos (p < 0.05). Consequently, females in the NP2 treatment showed improved body development. These results indicate a positive effect of a higher energy diet on assisted reproduction and body development in prepubertal heifers.
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Affiliation(s)
- Ricardo Braz de Toledo
- Brazilian Agricultural Research Corporation (Embrapa Cerrados), Planaltina, Brazil
- University of Brasília, Brasília, Brazil
| | - Otávio Augusto Costa de Faria
- University of Brasília, Brasília, Brazil
- Brazilian Agricultural Research Corporation (Embrapa Recursos Genéticos e Biotecnologia), Brasília, Brazil
| | - Ligiane Oliveira Leme
- Brazilian Agricultural Research Corporation (Embrapa Recursos Genéticos e Biotecnologia), Brasília, Brazil
| | | | - Roberto Guimarães
- Brazilian Agricultural Research Corporation (Embrapa Cerrados), Planaltina, Brazil
| | | | | | | | - Margot Alves Nunes Dode
- Brazilian Agricultural Research Corporation (Embrapa Recursos Genéticos e Biotecnologia), Brasília, Brazil
| | | | - Ivo Pivato
- University of Brasília, Brasília, Brazil
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Marques JCS, Maciel JPO, Denis-Robichaud J, Conceicao RS, Bega AM, Moore S, Sirard MA, Baes CF, Cerri RLA. The effect of progesterone concentrations during superovulation of Holstein heifers in a randomized trial. J Dairy Sci 2023; 106:9677-9690. [PMID: 37641352 DOI: 10.3168/jds.2022-23065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 05/17/2023] [Indexed: 08/31/2023]
Abstract
The aim of this study was to evaluate the effect of different progesterone (P4) concentrations during the follicular growth on the intensity of estrous expression, ovarian response to the superovulatory treatment, and embryo production and quality in superovulated heifers. A total of 63 Holstein heifers were randomly assigned into 2 experimental groups: Low P4 (n = 31) and High P4 (n = 32). Animals received a pre-synchronization protocol followed by a protocol of superovulation that included the allocated P4 treatment. Activity was monitored continuously by an automated activity monitor, and estrus characteristics (maximum intensity and duration) were recorded. Embryo collection was performed 7 d post artificial insemination (AI). Embryos were counted and graded from good or excellent (1) to degenerated (4). The outcomes of interest were: number and diameter of follicles at the time of AI, ovulation success (confirmed 7 d post-AI), time to estrus event, maximum intensity and duration of estrus, number and quality of embryos. Data were analyzed according to the type of outcome variable using logistic, linear, or Poisson regression models. A total of 105 embryos (High P4: n = 42; Low P4: n = 63) were graded for quality. Different P4 levels did not affect the maximum intensity (High P4 = 497.8 ± 23.9%; Low P4 = 542.2 ± 23.5%) or the duration (High P4 = 13.5 ± 1.5 h; Low P4 = 14.3 ± 1.4 h) of estrus. Heifers in the High P4 treatment had greater number of follicles at time of AI (High P4 = 16.6 ± 1.6 follicles; Low P4 = 13.9 ± 1.2 follicles), but with smaller diameter (High P4 = 11.3 ± 0.1 mm; Low P4 = 12.0 ± 0.1 mm) compared with Low P4. High P4 heifers tended to have better embryo quality compared with Low P4 heifers (odds ratio = 1.98; 95% CI = 0.90-4.35). High P4 heifers had less embryos than Low P4 heifers, but this was modified by the CIDR (intravaginal implant of P4) removal to estrus interval (interval 0-21 h: mean ratio = 1.15, 95% CI = 0.42-1.87; interval 22-46 h: mean ratio = 0.58, 95% CI = 0.27-0.96). Although estrous expression was not associated with embryo quality, as the duration and the maximum intensity of estrous expression increased, the number of embryos recovered 7 d post-AI increased (duration: mean ratio = 1.04; 95% CI = 1.03-1.05; maximum intensity: mean ratio = 1.50; 95% CI = 1.42-1.58). In conclusion, P4 during the follicular growth, and intensity of estrus, are playing a role in regulating the quality and the number of embryos produced by superovulated heifers. This study was supported by contributions from Resilient Dairy Genome Project and the Natural Sciences and Engineering Research Council.
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Affiliation(s)
- J C S Marques
- Faculty of Land and Food Systems, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - J P O Maciel
- Faculty of Veterinary Medicine, Rural Federal University of Pernambuco, Recife 52171-900, Canada
| | - J Denis-Robichaud
- Faculty of Land and Food Systems, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - R S Conceicao
- Faculty of Land and Food Systems, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - A M Bega
- Faculty of Veterinary Medicine, São Paulo State University, Botucatu 18168-000, Canada
| | - S Moore
- Faculty of Land and Food Systems, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - M A Sirard
- Department of Animal Sciences, Laval University, Quebec G1K 7P4, Canada
| | - C F Baes
- Department of Animal Biosciences, University of Guelph, Ontario N1G 2W1, Canada
| | - R L A Cerri
- Faculty of Land and Food Systems, University of British Columbia, Vancouver V6T 1Z4, Canada.
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Rhoads ML. Review: Reproductive consequences of whole-body adaptations of dairy cattle to heat stress. Animal 2023; 17 Suppl 1:100847. [PMID: 37567679 DOI: 10.1016/j.animal.2023.100847] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 04/27/2023] [Accepted: 04/28/2023] [Indexed: 08/13/2023] Open
Abstract
Heat stress has far-reaching ramifications for agricultural production and the severity of its impact has increased alongside the growing threats of global warming. Climate change is exacerbating the already-severe consequences of seasonal heat stress and is predicted to cause additional losses in reproductive performance, milk production and overall productivity. Estimated and predicted losses are staggering, and without advancement in production practices during heat stress, these projected losses will threaten the human food supply. This is particularly concerning as the worldwide population and, thus, demand for animal products grows. As such, there is an urgent need for the development of technologies and management strategies capable of improving animal production capacity and efficiency during periods of heat stress. Reproduction is a major component of animal productivity, and subfertility during thermal stress is ultimately the result of both reproductive and whole-body physiological responses to heat stress. Improving reproductive performance during seasonal heat stress requires a thorough understanding of its effects on the reproductive system as well as other physiological systems involved in the whole-body response to elevated ambient temperature. To that end, this review will explore the reproductive repercussions of whole-body consequences of heat stress, including elevated body temperature, altered metabolism and circulating lipopolysaccharide. A comprehensive understanding of the physiological responses to heat stress is a prerequisite for improving fertility, and thus, the overall productivity of dairy cattle experiencing heat stress.
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Affiliation(s)
- M L Rhoads
- School of Animal Sciences, Virginia Tech, Blacksburg, VA 24061, USA.
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Bastos NM, Goulart RS, Bambil DB, Bridi A, Mazzarella R, Alves L, da Silva Rosa PM, Neto AL, Silva SL, de Almeida Santana MH, Negrão JA, Pugliesi G, Meirelles FV, Perecin F, da Silveira JC. High body energy reserve influences extracellular vesicles miRNA contents within the ovarian follicle. PLoS One 2023; 18:e0280195. [PMID: 36626404 PMCID: PMC9831338 DOI: 10.1371/journal.pone.0280195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 12/22/2022] [Indexed: 01/11/2023] Open
Abstract
Aiming to evaluate the effects of increased body energy reserve (BER) in Nellore cows' reproductive efficiency, cows were fed with different nutritional plans to obtain animals with high BER (HBER; Ad libitum diet) and moderate BER (MBER: cows fed 70% of HBER group ingestion). To evaluate the BER, cows were weekly weighted and evaluated for subcutaneous fat thickness and insulin serum concentration along the experimental period. At the end of the experimental period, animals were submitted to estrous synchronization and artificial insemination. Animals were slaughtered approximately 120 h after ovulation induction and the reproductive tracts were collected for embryo recovery and samples collection. Cumulus-oocyte-complexes (COC) and follicular fluid were collected from 3-6 mm in diameter ovarian follicles to perform miRNA analysis of cumulus cells (CC) and extracellular vesicles from follicular fluid (EV FF). As expected, differences were observed among MBER and HBER groups for body weight, fat thickness, and insulin serum concentration. HBER animals showed lower ovulation and embryo recovery rates compared to MBER animals. Different miRNAs were found among CC and EV FF within groups, suggesting that the BER may influence follicular communication. This suggests that small follicles (3-6 mm diameter) are already under BER effects, which may be greater on later stages of follicular development.
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Affiliation(s)
- Natália Marins Bastos
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Rodrigo Silva Goulart
- Department of Animal Science, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Danilo Brito Bambil
- Department of Animal Science, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Alessandra Bridi
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Rosane Mazzarella
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Luana Alves
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Paola Maria da Silva Rosa
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Adomar Laurindo Neto
- Department of Animal Reproduction, College of Veterinary Medicine and Animal Science, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Saulo Luz Silva
- Department of Animal Science, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | | | - João Alberto Negrão
- Department of Basic Science, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Guilherme Pugliesi
- Department of Animal Reproduction, College of Veterinary Medicine and Animal Science, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Flávio Vieira Meirelles
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Felipe Perecin
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
| | - Juliano Coelho da Silveira
- Department of Veterinary Medicine, College of Animal Science and Food Engineering, University of São Paulo, Pirassununga, São Paulo, Brazil
- * E-mail:
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Saleem M, Yousuf MR, Ghafoor A, Riaz A. Effect of three schemes of ovum pick-up on the follicular dynamics, gene expression, and in-vitro developmental competence of oocytes in Sahiwal cattle. Reprod Domest Anim 2022; 57:1230-1243. [PMID: 35771838 DOI: 10.1111/rda.14198] [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: 05/13/2022] [Revised: 06/16/2022] [Accepted: 06/28/2022] [Indexed: 12/31/2022]
Abstract
This study aimed to compare the effect of three schemes of ovum pick-up (OPU) on follicular dynamics, oocytes recovery, oocytes quality, gene expression, nuclear maturation and in-vitro developmental competence of oocytes in Sahiwal cattle. Considering the follicle population, all the cows were divided equally in a 3 × 3 cross over design, and each cow received one of the three treatments: (a) twice weekly (TW; n = 6), (b) once weekly (OW; n = 6) and (c) bi-weekly OPU (BW; n = 6) in three periods, with the first OPU conducted on 4, 7 and 14 days after second dominant follicle puncture (DFP) in the TW, OW and BW OPU interval groups, respectively. The collected cumulus oocytes complexes (COCs) were graded into A, B, C and D grades depending on the number of layers of cumulus cells and homogeneous nature of cytoplasm. Nuclear maturation was assessed by staining the oocytes with Hoechst 33342. The growth rate (mm/day) of dominant follicle (DF) (F1) (0.49 ± 0.21 vs. 0.71 ± 0.26 vs. 1.30 ± 0.27) and first subordinate follicle (F2) (0.85 ± 0.27 vs. 0.71 ± 0.25 vs. 1.06 ± 0.29) did not differ (p > .05) among all the three groups. The proportion of animals bearing a corpus luteum (CL) in the BW OPU interval group (53.3%) was significantly higher (p < .05) as compared to TW (13.3%) and OW (18.3%) OPU interval groups. The number of medium-sized follicles and oocyte with grade A and B were significantly higher (p < .05) in the TW (1.16 ± 0.21 and 33.88 ± 0.03) OPU interval group as compared to the OW (0.88 ± 0.22 and 21.54 ± 0.03) and BW (0.55 ± 0.21 and 21.89 ± 0.02) OPU interval groups. However, the number of degenerated oocytes in BW (0.85 ± 0.16) OPU interval group was significantly higher (p < .05) as compared to the TW (0.16 ± 0.15) and OW (0.44 ± 0.16) OPU interval groups. Expression level of growth differentiation factor 9 in TW OPU interval group was significantly higher (p < .05) as compared to the OW and BW OPU interval groups. Likewise, expression level of bone morphogenetic protein 15 (BMP15) in the TW and BW OPU interval groups was significantly higher (p < .05) as compared to the OW OPU interval group. The nuclear maturation rate was significantly higher in the TW (63.64 ± 0.07) and BW (59.26 ± 0.08) OPU groups as compared to OW (51.43 ± 0.06) OPU interval group. However, the cleavage rate (59.30 ± 0.06 vs. 44.29 ± 0.06 vs. 56.67 ± 0.06) did not differ (p > .05) among the three groups. Whereas, the blastocyst rate tended to be higher (p = .06) in the TW (29.07 ± 0.05) and BW (28.33 ± 0.04) OPU interval groups as compared to OW (18.57 ± 0.05) OPU interval group. Taken together, it can be concluded that TW OPU interval scheme enhances the medium-sized follicles resulting in good quality oocytes, regulates the oocyte-derived paracrine factors, leading to higher nuclear maturation rates and improved embryonic development in-vitro.
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Affiliation(s)
- Muhammad Saleem
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Rizwan Yousuf
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Aamir Ghafoor
- Department of Microbiology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Amjad Riaz
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
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Mikkola M, Hasler JF, Taponen J. Factors affecting embryo production in superovulated Bos taurus cattle. Reprod Fertil Dev 2020; 32:104-124. [PMID: 32188562 DOI: 10.1071/rd19279] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Despite a long history of bovine superovulation research, significant commercial applications did not start until the early 1970s. For some 20 years thereafter, superovulation represented the primary tool for the production of cattle embryos. In the early 1990s, commercial invitro production (IVP) was initiated in cattle. Although ovum pick-up and IVP are now commercially practiced on a wide scale, superovulation and embryo recovery by flushing remain a widespread and very effective approach to the production of cattle embryos. This review covers both the history and the effects of multiple factors on superovulation in Bos taurus cattle. There are three general protocols for suitable pre-FSH programming of donors so that gonadotrophin-responsive follicles are available. Superovulation protocols vary widely based on the FSH source, the diluent used, the number and timing of FSH injections and the timing and utilisation of various prostaglandins, controlled internal progesterone releasing devices, gonadotrophin-releasing hormone, and other means of controlling follicular development and ovulation. The number of oocytes that can be stimulated to grow and ovulate within any given donor can be estimated by either ultrasound-guided sonography or by measuring concentrations of anti-Müllerian hormone in the blood. Animal-related factors that can influence the efficacy of superovulation include cattle breed, age, parity, genetics, lactational status and reproductive history. In addition, nutrition, stress, season, climate, weather and several semen factors are discussed.
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Affiliation(s)
- M Mikkola
- Geno SA, Store Ree AI Station, Ekebergveien 54, 2335 Stange, Norway; and University of Helsinki, Department of Production Animal Medicine, FIN-04920 Saarentaus, Finland; and Corresponding author.
| | - J F Hasler
- Vetoquinol USA, 4250N Sylvania Avenue, Fort Worth, TX 76137, USA
| | - J Taponen
- University of Helsinki, Department of Production Animal Medicine, FIN-04920 Saarentaus, Finland
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Seneda MM, Zangirolamo AF, Bergamo LZ, Morotti F. Follicular wave synchronization prior to ovum pick-up. Theriogenology 2020; 150:180-185. [PMID: 31982155 DOI: 10.1016/j.theriogenology.2020.01.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 01/12/2020] [Indexed: 11/28/2022]
Abstract
Among the reproductive biotechnologies, in vitro embryo production (IVEP) is an important tool for multiplying genetic material of superior merit. Recently, the number of embryos produced and transferred in vitro became significantly higher than that produced in vivo worldwide. In this context, the enhancement was attributable to ovum pick-up (OPU). With the advent of genomic technology, shortened breeding intervals, and increased selection accuracy, IVEP has attracted increasing attention for commercial use. The IVEP technique is well-established, but the embryo production rate has reached a plateau at 30-40%. Despite constant advances, the OPU/IVEP programs face some challenges that hinder the efficient application of the technique. Previous studies have shown that the quantity and quality of aspirated oocytes are essential factors for successful IVEP. This paper presents a brief overview of alternatives that can be employed to improve the process-seeking methods that assist in the recovery of better-quality oocytes and higher competence in OPU to improve embryo production. These strategies include using follicular wave synchronization prior to OPU, employing the influence of antral follicle populations, using the pre-OPU gonadotrophic stimulus and applying non-hormonal methods for selecting female donors.
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Affiliation(s)
- Marcelo Marcondes Seneda
- Universidade Estadual de Londrina, Laboratório de Reprodução Animal, DCV-CCA-UEL, Londrina, Parana, Brazil; National Institute of Science and Technology for Dairy Production Chain (INCT-LEITE), Universidade Estadual de Londrina, Rodovia Celso Garcia Cid-Campus Universitário, PO Box 10011, Londrina, Parana, 86057-970, Brazil.
| | - Amanda Fonseca Zangirolamo
- Universidade Estadual de Londrina, Laboratório de Reprodução Animal, DCV-CCA-UEL, Londrina, Parana, Brazil; National Institute of Science and Technology for Dairy Production Chain (INCT-LEITE), Universidade Estadual de Londrina, Rodovia Celso Garcia Cid-Campus Universitário, PO Box 10011, Londrina, Parana, 86057-970, Brazil
| | - Larissa Zamparone Bergamo
- Universidade Estadual de Londrina, Laboratório de Reprodução Animal, DCV-CCA-UEL, Londrina, Parana, Brazil
| | - Fábio Morotti
- Universidade Estadual de Londrina, Laboratório de Reprodução Animal, DCV-CCA-UEL, Londrina, Parana, Brazil
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Effect of reproductive methods and GnRH administration on long-term protocol in Santa Ines ewes. Trop Anim Health Prod 2017; 49:1303-1308. [PMID: 28608308 DOI: 10.1007/s11250-017-1329-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 05/31/2017] [Indexed: 10/19/2022]
Abstract
This study aimed to determine whether reproductive performance of ewes submitted to laparoscopic timed artificial insemination (TAI) would be similar to ante meridiem (AM)/post meridiem (PM) rule and assisted natural mating (NM), and whether GnRH may enhance the pregnancy rate in TAI. In experiment I, 191 non-lactating ewes were synchronized, then TAI was performed either 48 h after progesterone (P4) removal (TAI-48 h) or 12 h after estrus detection (AM/PM); moreover, some ewes were submitted to NM (NM) as control treatment. In experiment II, 247 non-lactating ewes were allocated in five treatments, a control (no-GnRH on protocol) and four treatments arranged in a factorial design 2 × 2. The factors were time and dose of GnRH: ewes that received either 10 μg (TAI-10 μg-36 h) or 25 μg of GnRH (TAI-25 μg-36 h) 36 h after P4 removal and ewes that received either 10 μg (TAI-10 μg-48 h) or 25 μg of GnRH (TAI-25 μg-48 h) at time of insemination, 48 h after P4 removal. In experiment I, pregnancy rate in TAI-48 h was lower (P = 0.03) than AM/PM and NM. Moreover, the probability of pregnancy in TAI-48 h was higher (P = 0.06) in ewes detected in estrus early. In experiment II, the use of GnRH in TAI protocols increased (P < 0.01) pregnancy rate at synchronization, and TAI-25 μ-48 h and TAI-10 μg-36 h treatments increased (P = 0.02) pregnancy rate compered to TAI-10 μg-48 h. We conclude that TAI decreased pregnancy rate compered to NM and AM/PM, which may be improved by GnRH use in TAI to synchronize ovulation.
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Mollo MR, Monteiro PLJ, Surjus RS, Martins AC, Ramos AF, Mourão GB, Carrijo LHD, Lopes G, Rumpf R, Wiltbank MC, Sartori R. Embryo production in heifers with low or high dry matter intake submitted to superovulation. Theriogenology 2017; 92:30-35. [PMID: 28237339 DOI: 10.1016/j.theriogenology.2017.01.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 01/06/2017] [Accepted: 01/07/2017] [Indexed: 12/21/2022]
Abstract
This study investigated the influence of feed intake on superovulatory response and embryo production of Nelore heifers. Pubertal heifers were kept in a feedlot and were submitted to the same diets, but with different levels of feed consumption: High (1.7 M; n = 20) or Low (0.7 M; n = 19) feed intake. Heifers in the 1.7 M treatment consumed 170% (2.6% of body weight [BW] in dry matter) and the 0.7 M heifers ate 70% (1.1% of BW in dry matter) of a maintenance diet. After 7 wk on these diets, heifers were treated with eight decreasing doses of follicle-stimulating hormone (FSH) given every 12 h, totaling 133 mg Folltropin (Folltropin-V; Bioniche Animal Health, Canada) per heifer. Seven d after AI, heifers had their uteri flushed and embryos were recovered and graded according to the International Embryo Technology Society standards. Data were analyzed using the GLIMMIX procedure of SAS and results are presented as least-squares means ± SEM (P < 0.05). At the onset of the FSH treatment (Day 0 of the protocol), 1.7 M heifers had greater body condition score (BCS), BW and serum insulin concentrations than 0.7 M heifers (4.1 ± 0.1 vs. 3.0 ± 0.1; 462.5 ± 10.1 vs. 382.7 ± 10.4 kg; and 14.3 ± 1.7 vs. 3.5 ± 0.8 μIU/mL, respectively). The 0.7 M heifers had more follicles ≥6 mm at the time of the last FSH (Day 7; 47.9 ± 6.4 vs. 23.5 ± 4.3 follicles), related to a better follicle superstimulatory response to FSH. Similarly, 0.7 M heifers had more corpora lutea at the time of embryo collection (33.6 ± 1.4 vs. 15.7 ± 0.9) than the 1.7 M heifers, which resulted in greater number of recovered embryos and ova (9.9 ± 0.7 vs. 6.7 ± 0.6) and viable embryos (5.3 ± 0.5 vs. 3.8 ± 0.4), despite having similar proportions of viable embryos (∼62%). A negative correlation between circulating insulin and follicle superstimulatory response to FSH was observed (r = -0.68). Therefore, we conclude that high feed intake, for a long period of time, compromised the superovulatory response and embryo production potential of Bos indicus heifers possibly related to the elevation in circulating insulin.
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Affiliation(s)
- Marcos R Mollo
- National Water Agency (ANA), Brasília, Federal District, Brazil
| | - Pedro L J Monteiro
- Department of Animal Science, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| | - Ricardo S Surjus
- Department of Animal Science, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| | | | - Alexandre F Ramos
- Embrapa Genetic Resources and Biotechnology, Brasília, Federal District, Brazil
| | - Gerson B Mourão
- Department of Animal Science, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| | | | | | - Rodolfo Rumpf
- Geneal Genetics and Animal Biotechnology, Uberaba, Minas Gerais, Brazil
| | - Milo C Wiltbank
- Department of Dairy Science, University of Wisconsin-Madison, Madison, WI, USA
| | - Roberto Sartori
- Department of Animal Science, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil.
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