Consulta: subjectFacets:"Pregnancy rate"
Registros recuperados: 12
Data/hora: 10/06/2024 11:05:50

Reproductive biology of the coypu, Myocastor coypus (Rodentia: Myocastoridae) in western Japan
Provedor de dados: 103
Autores: Runami,Iori; Gunji,Yousuke; Hishinuma,Mitsugu; Nagano,Masashi; Takada,Tatsuyuki; Higaki,Shogo.
We describe the reproductive biology of the coypu, Myocastor coypus (Molina, 1782), in western Japan, as an attempt to contribute to an efficient population control program of the coypu population. A total of 212 specimens (113 males and 99 females) were collected in the Tottori prefecture from February 2010 to January 2012. From the age estimation based on body weight and molar eruption pattern, we determined that both males and females reach sexual maturity at 4-6 months of age. Of the 72 mature females examined, 60 (83.3%) were pregnant, with a mean litter size of 6.5 ± 2.4 (mean ± SE). The onset of sexual maturity in the western Japanese population was relatively earlier when compared with indigenous and other introduced populations. Furthermore, the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Litter size; Pregnancy rate; Sexual maturity.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702013000200002

Effects of GnRH administration on ovulation and fertility in ewes subjected to estrous synchronization
Provedor de dados: 96
Autores: Cavalcanti,Amanda dos Santos; Brandão,Felipe Zandonadi; Nogueira,Luiz Altamiro Garcia; Fonseca,Jeferson Ferreira da.
The objective of this study was to verify the effects of GnRH on ovulation and pregnancy of ewes subjected to a short-term synchronization of estrus. Santa Inês and crossbred Santa Inês/Dorper ewes received 60 mg MAP sponges during 6 days plus 300 IU eCG and 30 µg d-cloprostenol 24 h prior to sponge withdrawal (SW). Ewes were assigned to receive 0.9% NaCl solution (Tcontrol; n = 32) or 25 µg GnRH (licerelin, T GnRH; n = 34) 24 hours after SW. Each group was assigned to intrauterine insemination by laparoscopy (n = 25) or to natural mating (n = 41). Artificial insemination was performed with a single dose of fresh semen. For controlled mating, females were exposed to males 12, 24, 36 and 48 hours after SW. Ten females per treatment were subjected to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Artificial insemination; Intravaginal progesterone insert; Ovulation; Pregnancy rate; Sheep.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012000600014

Pre- and post-calving forage systems and reproductive performance of primiparous cows
Provedor de dados: 96
Autores: Lobato,José Fernando Piva; Menegaz,André Luís; Pereira,Antonio Carlos Gonçalves.
During pre and post calving periods, it was evaluated the influence of the following forage systems on reproductive performance of primiparous cows: natural pasture during pre and post-calving periods; natural pastures during pre-calving period and improved pastures during post-calving period; improved pastures during pre-calving and natural pasture during post-calving; improved pasture during pre- and post-calving periods. The lowest body weights and body condition scores were observed on cows kept on natural pastures pre-calving (384.3 kg and 3.31; 391.4 kg and 3.60), followed by those on improved pastures during pre-calving and on natural pasture during post-calving period (424.4 kg and 3.60), finally, cows on improved pasture during pre- and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Body condition; Brangus; Improved pastures; Natural pastures; Pregnancy rate; Weights.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010000900029

Calving sub-season and reproductive efficiency of beef cows
Provedor de dados: 96
Autores: Reinher,Cristiane; Barcellos,Júlio Otávio Jardim; Peripolli,Vanessa; Prates,Ênio Rosa; Canozzi,Maria Eugênia Andrighetto.
It was evaluated in this work the effect of calving sub-season on the pregnancy rate of 7,726 multiparous Hereford beef cows grazing on natural pastures in southern Brazil, from 1994 to 2007. Calving sub-season periods were divided in 20-day intervals from August 12th to 31st; from September 1st to 20th; from September 21st to October 10th; from October 11th to 31st; from November 1st to 20th. Calving in each sub-season and pregnancy rate (PR) were analyzed by the Chi-square test. Overall means of each sub-season were 92.7% (from August 12th to 31st), 90.6% (from September 1st to 20th), 82.1% (from September 21st to October 10th), 77.7% (from October 11th to 31st), and 70.6% (from November 1st to 20th). Calving sub-season significantly influenced pregnancy...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Calving date; Cow-calf; Multiparous; Pregnancy rate.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010001000012

Development and reproductive performance of Hereford heifers of different frame sizes up to mating at 14-15 months of age
Provedor de dados: 96
Autores: Silva,Maurício Dallmann da; Lobato,José Fernando Piva; Vaz,Ricardo Zambarda; Eloy,Lidiane Raquel; Vaz,Márcia Bitencourt.
ABSTRACT Body development and reproductive performance of a hundred forty-two 14 to 15-month-old heifers, classified at weaning according to frame size as small, medium, and large, were evaluated. The parameters evaluated were: body weight, hip height, body condition score, weight gain, ovarian activity, and pregnancy rate. At weaning, body weight and hip height were significantly different among frame scores, (small – 133.0 kg, 92.2 cm; medium – 158.5 kg, 96.6 cm; and large – 185.2 kg; 100.2 cm). After weaning, heifers grazed together on natural pastures during the autumn and on ryegrass (Lolium multiflorum La.) during the winter and spring. Frame score differences remained until the beginning of the breeding season (BS), starting on average at 14 months...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Age at conception; Average daily gain; Body condition score; Hip height; Ovarian activity; Pregnancy rate.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982018000100400

Influence of weaning age on the reproductive efficiency of primiparous cows
Provedor de dados: 96
Autores: Vaz,Ricardo Zambarda; Lobato,José Fernando Piva; Restle,João.
The effects of weaning age (90 days or 156 days) of female beef calves were evaluated on their subsequent performance from the beginning of the first pregnancy and the end of the second breeding season, at 22/24 months of age. During pregnancy, heifers were managed as a single group on Brachiaria brizantha cv. Marandu pasture; after calving, on bristle oats (Avena strigosa Schreb) and ryegrass (Lolium multiflorum Lam.); and on Brachiaria humidicula pasture during the second reproductive period. The characteristics studied were not influenced by calf weaning age. Heifers submitted to early or conventional weaning weighed 354.5 and 351.9 kg in the post-calving, and 363.4 and 359.2 kg when they weaned their calves. Average daily gain during the breeding...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Body condition; Early weaning; Heifers; Pregnancy rate; Weaning age; Weight gain.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010000200011

Natural and improved natural pastures on the reproductive performance of first-calf beef cows
Provedor de dados: 96
Autores: Tanure,Soraya; Pötter,Bernardo Augusto Albornoz; Lobato,José Fernando Piva.
This work evaluated the reproductive performance of first-calf cows at three years of age, submitted or not to protein supplementation at yearling on natural pastures. After calving, cows were managed on natural or improved pastures. The feeding managements were the following: on natural pastures as yearlings and during pregnancy, post-calving period and breeding season; on natural pastures with protein supplement as yearlings and only natural pasture during pregnancy, post-calving and breeding season; on natural pastures as yearlings and during pregnancy and on improved natural pastures (Lolium multiflorum L., Trifolium repens cv. Yi and Lotus corniculatus cv. São Gabriel) during the post-calving period and breeding season; on natural pastures with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Body condition score; Body weight variation; Braford; Post-calving; Pregnancy rate.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000300030

Economic evaluation of puberty induction of nulliparian Nellore heifers using intravaginal device and melengestrol acetate
Provedor de dados: 109
Autores: Pereira,Luiz Carlos; de Souza Ferreira,Renan; Fujii Gongalves,Rony; Vinhas Ítavo,Luís Carlos; Signor Kohl,Endyara; Menezes Dias,Alexandre; Barbosa Ferreira,Marcos; Espínala Carvalho,Cristiano Marcelo; Gongalves Mateus,Rodrigo.
Abstract The present study evaluates the economic viability of puberty induction in nulliparous Bos taurus indicus Nellore breed heifers using an intravaginal device of fourth-use and melengestrol acetate (MGA®). The experiment was undertaken in the Nossa Senhora Aparecida Farm, Terenos city, Mato Grosso do Sul, Brazil, and was utilized a completely randomized experimental design in a 2 x 3 factorial scheme. Two age classes were included in the study, which were divided into 348 precocious (early-cycle) heifers, aging 16-18 months, weighting an average of 264.6 kg and 543 conventional-cycle heifers aging 24-26 months averaging 346.8 kg. The three treatments were as follows: control without the induction of follicle formation (treatment 1); treatment 2:...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Estrus induction; Fertility; Reproductive efficiency; Economic return; Pregnancy rate.
Ano: 2019
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122019000300205

Bovine semen thermoresistance tests and their correlation with pregnancy rates after fixed-time artificial insemination
Provedor de dados: 45
Autores: Talini,R.; Kozicki,L.E.; Gaievski,F.R.; Polo,G.; Lima,L.G.F.; Santiago,J.; Segui,M.S.; Weiss,R.R.; Galan,T.G.B.
ABSTRACT The objective of the study was to determine whether or not there is a correlation between thermoresistance tests (TT) after semen thawing and pregnancy rate (PR) after fixed-time artificial insemination (FTAI). Four different TT were performed on ten samples used for AI; a rapid test (RTT) (30min / 46°C) and three slow tests (STT): STT1 (60min/38°C), STT2 (180min/38°C), and STT3 (300min/38°C). Two hundred and fifteen multiparous crossbred cows were submitted to FTAI under the following protocol: on day zero (d0) the animals received a P4 device +EB; on d7 PGF2α; on d8 P4 was removed and eCG+EC were administered; IATF was performed on d10. Three gestational diagnoses (G D) were performed on d40, d70 and d120. The mean sperm motility (%) in RTT and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sperm motility; Casa; Pregnancy rate; Beef cows; Semen thermoresistance test.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352019000602085

Probability of pregnancy in beef heifers
Provedor de dados: 45
Autores: Faria,D.P.; Costa,M. D. da; Raidan,F. S. S.; Ruas,J. R. M.; Júnior,V. R. R.; Toral,F. L. B.; Aspiazú,I.
This study aimed to evaluate the influence of initial weight, initial age, average daily gain in initial weight, average daily gain in total weight and genetic group on the probability of pregnancy in primiparous females of the Nellore, 1/2 Simmental + 1/2 Nellore, and 3/4 Nellore + 1/4 Simmental genetic groups. Data were collected from the livestock file of the Farpal Farm, located in the municipality of Jaíba, Minas Gerais State, Brazil. The pregnancy diagnosis results (success = 1 and failure = 0) were used to determine the probability of pregnancy that was modeled using logistic regression by the Proc Logistic procedure available on SAS (Statistical..., 2004) software, from the regressor variables initial weight, average daily gain in initial weight,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Average daily gain; Beef cattle; Breeding season; Pregnancy rate.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352014000601795

Extended culture up to the blastocyst stage: a strategy to avoid multiple pregnancies in assisted reproductive technologies
Provedor de dados: 48
Autores: Sepúlveda,Soledad J; Portella,Jimmy R; Noriega,Luis P; Escudero,Ernesto L; Noriega,Luis H.
The aim of this study was to review the experience and outcomes of assisted reproduction cycles with embryos grown up to day 5 of development, comparing different parameters according to the ages of the patients. We retrospectively studied 1,874 assisted reproduction cycles where embryo culture was extended up to the fifth or sixth day of development. All IVF and ICSI cycles were included, comparing, according to patient age, the following rates: blastocyst formation, pregnancy, implantation and abortion. As control, we analyzed cycles with donated oocytes from young donors (OD). The number of embryos reaching the blastocyst stage is similar in all groups of patients. Only the OD group was different in terms of blastocyst formation, pregnancy and...
Tipo: Journal article
Palavras-chave: Blastocyst; Long-term culture; Pregnancy rate; Implantation rate.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000200012

Reproductive performance of Nellore heifers raised in extensive system undergoing different vaccination protocols in fixed-time artificial insemination (FTAI)
Provedor de dados: 65
Autores: Schillings Neto,Ernest; Nogueira,Eriklis; Jardim,Rodrigo; Abreu,Urbano Gomes Pinto de; Sterza,Fabiana Andrade de Melo; Pellegrin,Aiesca Oliveira; Juliano,Raquel Soares.
ABSTRACT:  This study evaluated the reproductive performance of Nellore heifers without previous vaccination undergoing fixed-time artificial insemination (FTAI) and subsequent natural breeding under different vaccination protocols against infectious bovine herpesvirus 1 (BHV-1), bovine viral diarrhea virus (BVDV), and bovine leptospirosis (BL). A total of 763 animals were included; the group assignment was as follows: T1, control without vaccination; T2, vaccination against BL; T3, vaccination against BHV-1and BVDV; T4,vaccination against combination of BL + BHV-1and BVDV. Vaccination was started 30 days before FTAI (D-40), and a booster dose was administered at D-10. Serological tests were used to verify the occurrence rate of natural infection by BL,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Beef cattle; Immunization; Leptospirosis; Pregnancy rate; Viral diseases.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019001100701