17PREVENTION OF ANESTRUS USING AN INTRAVAGINAL PROGESTAGEN DEVICE COMBINED WITH 17²-ESTRADIOL, GNRH, AND PGF2± AT 60 DAYS POSTPARTUM IN DUAL PURPOSE CROSSBRED ZEBU COWS

2004 ◽  
Vol 16 (2) ◽  
pp. 131 ◽  
Author(s):  
R. Palomares-Naveda ◽  
F. Perea-Ganchou ◽  
H.J. Hernandez-Fonseca ◽  
J. Sandoval-Martinez ◽  
A. De Ondiz-Sanchez ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Reproductive Performance ◽  
Group Treatment ◽  
Body Condition Score ◽  
Control Group ◽  
Chi Square ◽  
Dual Purpose ◽  
T1 And T2 ◽  
Intravaginal Device ◽  
Zebu Cows

In order to study the effect of an intravaginal device (sponge) impregnated with Medroxyprogesterone acetate (MAP) on estrus induction and fertility, an assay was carried out on a commercial farm located in Zulia state, Venezuela. Eighty-four noncyclic (milk progesterone level <0.5ng/mL) suckled crossbred cows (B. taurus×B. indicus) at 60 days postpartum and 3–3.5 body condition score (scale 1–5) were randomly allotted to one of the following treatments: T1 (n=22), intravaginal device impregnated with 250mg of MAP during 7 days+50mg of MAP and 5mg of 17β-estradiol (17β-E) i.m. on the day of device insertion (Day 0) and 1.5mg of 17β-E i.m. on Day 8 (Pregnaheat-E®; VIATECA, Venezuela); T2 (n=28), 17β-E given at Day 0 was replaced by 20μg of busereline (Conceptal® Hoescht, A. Germany)+injection of 25mg of dinoprost (Lutalyse® Pharmacia Upjohn, Kalamazoo, MI, USA) on Day 7 and 1.5mg of 17β-E 12h after device removal (Day 8); T3 (control group; n=34), without treatment. Animals detected in heat were inseminated in the uterine body 9 to 12 hours later in routine AM-PM. Pregnancy diagnose was carried out at 60days after AI by transrectal examination. Studied variables were: estrus rate (ER), pregnancy rate (PR), anoestrus rate (AR), and partum-conception interval (PCI). Variables were analyzed by frequency procedures and chi-square test of Statistical Analysis System (SAS). PCI was analyzed by variance model (PROC GLM) and compared by Ls means. Results are shown in Table 1. T1 and T2 showed higher ER and PR (P<0.05) than T3. AR was lower (P<0.05) in T1 and T2 than T3. PCI was significantly reduced (P<0.05) in T1, but not in T2 versus T3. The cows treated with MAP showed greater estrus and pregnancy rate, shorter partum-conception interval and lower anoestrus rate than the control group. Treatment with the intravaginal device was effective to prevent postpartum anoestrus and to improve reproductive performance in dual purpose zebu crossbred suckled cows. Table 1. Effect of an intravaginal progestagen device on reproductive performance in crossbred Zebu cows

116 PREGNANCY RATES AFTER ADMINISTRATION OF EQUINE CHORIONIC GONADOTROPIN (eCG) AT PROGESTERONE INTRAVAGINAL DEVICE REMOVAL AND 14 DAYS AFTER FIXED-TIME AI IN BEEF CATTLE

2011 ◽  
Vol 23 (1) ◽  
pp. 163 ◽  
Author(s):  
R. Núñez ◽  
T. de Castro ◽  
L. Cutaia ◽  
G. Bó ◽  
A. Menchaca
Keyword(s):  
Beef Cattle ◽  
Pregnancy Rate ◽  
Body Condition Score ◽  
Fetal Loss ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Control Group ◽  
Device Removal ◽  
Embryo Survival ◽  
Intravaginal Device

An important proportion of embryonic deaths in cattle occur during the critical period of embryo development and maternal recognition of pregnancy. High serum progesterone concentrations during this period are associated to higher embryo survival, and the use of eCG could enhance luteal activity. Two experiments were carried out to evaluate the effect of administering eCG at the time of removal of a progesterone-releasing device and 14 days after fixed-time artificial insemination (FTAI) in beef cattle. Multiparous suckled cows between 60 and 90 days postpartum (n = 297; Exp. 1), and two-year old prepuberal heifers (n = 689; Exp. 2) with a body condition score (BCS) between 3.5 and 5 (1 to 8 scale) were used. At the beginning of the experiments, none of females used had a corpus luteum detected by ultrasonography. Females received an intravaginal device containing 0.5 g progesterone (DIB 0.5, Syntex, Buenos Aires, Argentina) and 2 mg oestradiol benzoate i.m. (Benzoato de Oestradiol, Syntex). Eight days later, 500 μg of cloprostenol (Ciclase DL, Syntex) and 0.5 mg oestradiol cypionate (Cipiosyn, Syntex) were given i.m. and devices were removed; FTAI was performed 52 to 56 h after DIB removal. At the time of device removal, the animals were randomly allocated to 4 groups, to receive 400 IU of eCG i.m. (Novormon, Syntex) or placebo at device removal and/or 14 days after FTAI, in a 2 × 2 factorial design. Control group did not receive eCG. In Exp. 1, nose plates were placed on calves on the day of DIB insertion and left for 10 days in order to prevent suckling. Pregnancy diagnosis was performed by ultrasonography at 30 and 60 days after FTAI. Data were analysed by logistic regression. Pregnancy rate at 30 days after FTAI was affected by treatment (P < 0.05; Table 1). Late embryonic/fetal loss rates (non-pregnant females at 60 days after FTAI over those pregnant at 30 days) were 1.6% (3/182) for cows in Exp. 1 and 4.8% (14/292) for heifers in Exp. 2; no differences were detected among groups. In conclusion, administration of 400 IU of eCG at device removal increases pregnancy rate, both in anestrus cows and heifers. However, the administration of a second dose of eCG 14 days after FTAI suggests a possible effect on embryo survival within the first 30 days of pregnancy in cows but not in heifers. Further studies are required to confirm these results. Table 1.Pregnancy rates after administration of eCG at time of progesterone device removal and/or 14 days after insemination in beef cattle Supported by Syntex.

13 USE OF A NEW INTRAVAGINAL DEVICE TO RELEASE PROGESTERONE IN FIXED-TIMED ARTIFICIAL INSEMINATION IN NELLORE COWS (BOS TAURUS INDICUS)

2010 ◽  
Vol 22 (1) ◽  
pp. 164
Author(s):  
F. A. Braga ◽  
F. J. D. Pardo ◽  
P. H. Miguez ◽  
A. Kehrle ◽  
J. R. V. Pimentel ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Artificial Insemination ◽  
Body Condition Score ◽  
Estradiol Benzoate ◽  
Sao Paulo ◽  
Pregnancy Rates ◽  
Control Group ◽  
São Paulo ◽  
Effect Of Treatment ◽  
Intravaginal Device

Artificial insemination results can be improved using fixed-timed AI (FTAI). Currently, progesterone release devices, indispensable in FTAI procedures, such as DIB® (Schering-Plough, Kenilworth, NJ, USA), are made of silicone, a nonbiodegradable biocompatible polymer. Recently, biodegradable progesterone (P4)-releasing devices made of poly(3-hydroxy)butyrate-valerate copolymer (PHB-V) and poly-ϵ-caprolactona (PCL) have been developed. To investigate the efficiency on pregnancy rate of FTAI programs using a new intravaginal device made of PHB-V (Progestar®, Innovare, São Paulo, Brazil), 240 Nellore (Bos indicus) cows, between 3 and 8 years of age, were randomly assigned to 2 experiments. In experiment 1, new P4 devices DIB (control group, DIB1; n = 60) were compared with PHB-V (Progestar1; n = 76); in experiment 2, previously used DIB (DIB2; n = 52) and PHB-V (Progestar2; n = 52) devices were compared. All groups were treated with 2 mg of estradiol benzoate i.m. (Innovare) and received the intravaginal device according to group (Day 0). Together with P4 device withdrawal (Day 8) all animals received 300IU of eCG i.m. (Novormon®, Schering-Plough) and 150 μg i.m. of D-cloprostenol (Croniben®, Biogenesis-Bagó, Buenos Aires, Argentina). On Day 9, all cows were treated with 1 mg of estradiol benzoate and the FTAI was performed 30 h later. The data were submitted to ANOVA (PROC GLM of SAS, SAS Institute, Cary, NC, USA), separating as causes of variance the effect of treatment, postpartum period (PPP1-45 until 70 days and PPP2-71 until 90 days), body condition score (BCS4, BCS5, and BCS6 using a 1 to 9 scale), cyclicity (cycling and noncycling) and clean-up bulls (5 bulls nominated with numbers 1 to 5). Significant differences were considered to have P < 0.05. In experiment 1, interactions were not significant, there was no effect of treatment on FTAI (DIB1: 66.7% v. Progestar1: 65.8%) or breeding season pregnancy rates (BSPR; DIB1: 95.0% v. Progestar1: 94.7%) and no effect of other variables on FTAI pregnancy rates (FTAIPR) and BSPR. In experiment 2 there was no effect of treatment on FTAIPR (DIB2: 61.6% v. Progestar2: 55.8%) and BSPR (DIB2: 94.2% v. Progestar2: 88.5%). As ANOVA indicated a significant effect of clean-up bulls on BSPR, Tukey test was used to split it up. A bull of the Progestar2 group had lower performance (41.7%) causing the difference (albeit nonsignificant) on BSPR. This experiment showed that Progestar and DIB had the same efficiency on pregnancy rate and both treatments have the potential to produce FTAIPR >50% and BSPR >90%. Fapesp-Fundação de Amparo à Pesquisa do Estado de São Paulo. CNPq-Conselho Nacional de Desenvolvimento Científico e Tecnológico.

scholarly journals 19POSTPARTUM ANESTROUS TREATMENT WITH INTRA-VAGINAL PROGESTERONE DEVICE OR CALF REMOVAL FOR 120 HOURS IN SUCKLED CROSSBRED DUAL PURPOSE COWS

2004 ◽  
Vol 16 (2) ◽  
pp. 132 ◽  
Author(s):  
F. Perea-Ganchou ◽  
E. Soto-Belloso ◽  
R. Palomares-Naveda ◽  
A. De Ondiz ◽  
H.J. Hernandez-Fonseca ◽  
...  
Keyword(s):  
Bos Taurus ◽  
Body Condition Score ◽  
Bos Indicus ◽  
Least Square ◽  
Control Group ◽  
Chi Square ◽  
Dual Purpose ◽  
Tropical Conditions ◽  
Calf Removal ◽  
Chi Square Analysis

Postpartum anestrus is the main reproductive problem that affects crossbred cattle production in Venezuela. (Soto et al., 2002 Theriogenology 57, 1503–1510; Soto et al., 2000 Revista Científica FCV-LUZ 10, 391–398). In order to reduce the postpartum anestrus and lower the calving to conception interval, 167 crossbred (Bos indicus×Bos taurus) anestrous cows between 90 and 130 days postpartum with body condition score 3 (scale 1–5) were randomly allotted to one the following treatments: 1) PH (n=59), intravaginal sponge (IS) impregnated with 250mg of medroxyprogesterone acetate (MAP) during 7 days+50mg of MAP and 5mg of 17β-estradiol (17β-E) i.m. at the day of sponge insertion (Day 0), plus 500 IU of eCG i.m. at Day 5 and1.5mg of 17β-E i.m. at Day 8 (PREGNAHEAT-E, VIATECA, Villa del Rosario, Venezuela); 2) CR (n=57), 120-h temporary calf removal; and 3) CG (n=20), control group. Work was performed in a commercial farm located in a subhumid tropical forrest region. Estrus, first service conception and pregnancy rate were analyzed by chi-square analysis. The intervals to conception were analyzed using analysis of variance (GLM) and the means was compared by least square means method. To evaluate the treatment effect, the interval to conception of each pregnant cow during the first 100 days were considered for the analysis. This interval (days) was significantly (P≤0.05) higher in the PH treatment (155.9±7.3) compared to control (174.4±8.1) but no differences were shown between PH and CR (161.0±7.8). Other results are shown in Table 1. PH treatment improved the estrus and pregnancy rates and shorten the interval to conception indicating that this is a promising anestrous treatment for suckled crossbred dual purpose cows under tropical conditions. Table 1. Reproductive performance of postpartum anestrous suckled cows treated with intravaginal progesterone or temporary calf removal

Effect of active or passive immunization against steroids on reproductive performance of ewes in different levels of body condition at mating

1986 ◽  
Vol 43 (2) ◽  
pp. 285-292 ◽  
Author(s):  
S. M. Rhind ◽  
B. A. Morris ◽  
Jill Clayton ◽  
J. M. Doney ◽  
R. G. Gunn ◽  
...  
Keyword(s):  
Body Condition ◽  
Reproductive Performance ◽  
Body Condition Score ◽  
Passive Immunization ◽  
Treated Group ◽  
Ovulation Rate ◽  
Control Group ◽  
Absolute Increase ◽  
Wide Range ◽  
Antibody Titres

ABSTRACTBorder Leicester × Scottish Blackface (Greyface) ewes of three groups, each comprising 118 animals in a wide range of body condition scores, were mated at a synchronized oestrus in mid October. The ewes were passively immunized against testosterone (group P), actively immunized against androstenedione (group F), or not treated (group C). All ewes were slaughtered at return to service or at 35 to 45 days of pregnancy and ovulation rates and numbers of embryos present were determined. Mean ovulation rates of ewes in group P were higher than in those in group C (P < 0·05) and this difference was evident at most levels of body condition. The absolute increase in ovulation rate, compared with the control group, was similar at all condition scores. Mean ovulation rates of ewes in group F were higher than those in group C (P < 0·001) and the magnitude of the increase was greater in ewes in higher condition scores. The incidence of ova wastage was variable but differences between treatments in mean ovulation rate were generally reflected in mean litter size. The conception rates of immunized ewes were depressed compared with those of control animals, particularly in ewes with a body condition score less than 3·0 at mating. Consequently, there was no improvement in the potential lambing rate of immunized ewes following only one cycle of mating. Circulating antibody titres were not related to conception rate or body condition at mating and were related to ovulation rate only in group F ewes. It is concluded that immunization against steroids, using either passive or active techniques, can improve the reproductive performance of individual ewes but improvement in the performance of the flock as a whole may only be achieved under optimal conditions of nutrition and season.

scholarly journals Comparison of the effects of Presynch-Ovsynch, Presynch- Ovsynch+CIDR, and G6G protocols on the reproductive performance of lactating Holstein cows in the postpartum period

2021 ◽  
Vol 53 (4) ◽  
Author(s):  
Hesam Kohsari ◽  
Khatereh Berenjian
Keyword(s):  
Serum Concentration ◽  
Pregnancy Rate ◽  
Reproductive Performance ◽  
Body Condition Score ◽  
Dairy Farm ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Holstein Cows ◽  
Treatment Protocols ◽  
Ovulatory Follicle

This study was performed on an industrial dairy farm near Tehran province, Iran, on 666 lactating Holstein cows from September 2019 to June 2020 in order to eliminate the harmful effects of heat stress on the reproductive performance of the cows. The hypothesis of the recent study was that by increasing the serum concentration of progesterone (P4) in the luteal phase before insemination in the form of Presynch-Ovsynch+CIDR (POC) and G6G protocols, the pregnancy rate of cows would be increased compared to the Presynch-Ovsynch (PO) protocol. The aim of the present study was to evaluate the effects of Presynch-Ovsynch (PGF2α-14d- PGF2α-12d-Ovsynch (OVS: GnRH(GnRH1)- 7d-PGF2α(PG)-2d-GnRH)-18h-Fixed-time artificial insemination (FTAI), n=212), Presynch-Ovsynch+CIDR (similar to the PO protocol, plus the use of a CIDR for 7 days, from the start of the OVS+FTAI protocol to the time of PG injection, n=230), and G6G (PGF2α- 2d-GnRH-6d-OVS+FTAI, n=224) protocols on the reproductive performance and pregnancy rate of lactating Holstein cows. The average body condition score (BCS) for the cows was about 2.5 at the time of the onset of the OVS+FTAI program. The average daily milk production for cows at the time of the start of the OVS+FTAI program was 38.3 kg/day. On average, the studied cows were inseminated 86 days postpartum. Implementation of the G6G protocol in comparison to the PO and POC protocols increased the serum concentration of P4 at GnRH1 (P=0.04). The cows that received the G6G protocol had a greater number of corpuses luteum (CL) on their ovaries at PG in comparison to the cows in the PO and POC protocols (P=0.03 and P=0.05, respectively). For all treatment protocols, the pregnancy rate of cows with &gt;2 CLs on their ovaries at PG was significantly higher than for cows with ≤2 CLs on their ovaries at this time. The overall pregnancy rate for all cows studied was 42%. Separately, pregnancy rates for cows in PO, POC, and G6G protocols were calculated at 36.7%, 41.7%, and 47.3% respectively. The highest and the lowest pregnancy rates were obtained in the G6G and PO protocols, respectively (P=0.03). It can be concluded that the G6G protocol increased the pregnancy rate of cows in comparison to the PO but not to the POC protocol. This result can be attributed to the increase in serum concentration of P4 at GnRH1 and the greater number of CLs at PG following implementation of the G6G compared to the PO protocol. Although CIDR administration in the POC protocol led to an increase in the pregnancy rate of cows compared to the PO protocol, possibly by increasing the synchrony rate and the quality of the ovulatory follicle, this increase was not statistically significant (P=0.09).

scholarly journals AVALIAÇÃO DO DESEMPENHO REPRODUTIVO DE VACAS NA REGIÃO DO PANTANAL SUL-MATO-GROSSENSE SUBMETIDAS A IATF Com Aplicação De GnRH

Nativa ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 281-285
Author(s):  
Gabriel Rodrigo Hass Perucchi ◽  
Gabriela de Souza Sartori ◽  
Richarlla Aparecida Buscariol Silva ◽  
Murilo da Silva Garcia ◽  
Rodrigo José Delgado Jardim ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Pregnancy Rate ◽  
Reproductive Performance ◽  
Artificial Insemination ◽  
Body Condition Score ◽  
The Body ◽  
Mato Grosso ◽  
Condition Score ◽  
Timed Artificial Insemination ◽  
Mato Grosso Do Sul

A Inseminação artificial em tempo fixo (IATF) está se difundindo no Brasil, pois contribui para o aumento da produtividade. O objetivo neste trabalho foi avaliar o uso do GnRH em protocolos de IATF de vacas criadas no pantanal Sul-mato-grossense. Participaram da pesquisa 531 vacas paridas da raça Nelore, que foram avaliadas de acordo com o escore de condição corporal (ECC), submetidas a três tipos de protocolos de IATF (lote 1, 2 e 3). Após 40 dias da inseminação artificial foi realizado diagnóstico de gestação. As matrizes que não receberam GnRH no lote 1 (estro aparente), lote 2 (estro parcial) e lote 3 (sem apresentação de estro) apresentaram, respectivamente 55,4%, 19,2% e 25,9% de prenhez, enquanto as que receberam o fármaco apresentaram 48,6%, 37,2% e 38,8%. Relacionado ao ECC, pode-se observar que a maior taxa de prenhez ocorreu em animais com ECC 3. Primíparas apresentaram melhor taxa de prenhez quando receberam GnRH independente do ECC. Concluiu-se que o uso de GnRH mostrou-se eficiente para melhoria da taxa de prenhez principalmente em primíparas, assim como nos animais que não apresentaram estro ou apresentaram estro parcial, e que matrizes com ECC 3 apresentaram melhores taxas de prenhez que vacas com escore inferior. Palavras-chave: bovino de corte; inseminação artificial em tempo fixo; produtividade; GnRH; Nelore.   Evaluation of cow reproductive performance in the region of Mato Grosso do Sul swamp submitted to TAI with GnRH application   ABSTRACT: The technique of timed artificial insemination (TAI) is spreading in Brazil, as it contributes to the increase of productivity. The objective of this work was to evaluate the use of GnRH in TAI protocols of cows raised in the swamp of Mato Grosso do Sul. 531 Nelore breed calved cows participate in the survey, which were evaluated according to the body condition score (BCS), and then performed three types of TAI protocols (batch 1, 2 and 3). After 40 days of the insemination, a pregnancy diagnosis was made. The matrices that did not receive GnRH in batch 1 (apparent oestrus), batch 2 (partial oestrus) and batch 3 (no oestrus presentation) presented respectively 55.4%, 19.2% and 25.9% of pregnancy, while those receiving the drug showed 48.6%, 37.2% and 38.8%. Related to BCS, it can be observed that the highest pregnancy rate occurred in animals with BCS 3. Primiparous had a better pregnancy rate when receiving GnRH regardless of BCS. It was concluded that the use of GnRH was efficient to improve the pregnancy rate mainly in primiparous as well as animals that showed no oestrus or partial oestrus, and matrices with BCS 3 had better pregnancy rates than cows with lower scores. Keywords: beef cattle; timed artificial insemination; productivity; GnRH; Nelore.

scholarly journals Studies on Factors Affecting Pregnancy Rate after Treatment of Anestrus Buffaloes in Chitwan District

2019 ◽  
Vol 7 (2) ◽  
pp. 248-256
Author(s):  
Navaraj Chapagain ◽  
Bhuminandan Devkota ◽  
Gokarna Gautam ◽  
Shyam Kishor Sah ◽  
Dinesh Bhattarai
Keyword(s):  
Pregnancy Rate ◽  
Body Condition Score ◽  
Parasitic Infection ◽  
Fixed Time ◽  
Feeding Practice ◽  
Chi Square ◽  
Mean Values ◽  
Factors Affecting ◽  
Exact Test ◽  
Nutritional Parameters

This study was designed to determine the effects of age, parity, feeding practice, Body Condition Score (BCS), blood nutritional parameters, types of anoestrus, and length of anoestrus on pregnancy rate of anoestrus buffaloes after their treatment with ovsynch protocol followed by fixed time artificial insemination. Blood samples were collected on the day ovsynch protocol and analyzed. The mean values of the nutritional parameters between different groups were compared by Students t test and pregnancy rate was compared by Fisher’s exact test or Chi-square test. The overall pregnancy rate in buffaloes was 28.6%, when checked on day 41 and 64.3% on day 102 of FTAI. Blood glucose, cholesterol, calcium and phosphorus level was found to be significantly higher (p<0.05) in pregnant than in non-pregnant buffaloes. Pregnancy rate was higher in silent estrus buffaloes. Buffaloes with BCS ≥3 had higher pregnancy rate than those with BCS < 3. Similarly, pregnancy rate was higher in lactating than in non-lactating buffaloes. While young buffaloes of age <10 year responded better than old buffaloes of age ≥10 year. Buffaloes which were free from gastrointestinal parasitic infection had higher pregnancy rate. In conclusion, ovsynch protocol produces a good pregnancy in anoestrus buffaloes; however, state of true anoestrus, older age and poor BCS with poor nutritional management adversely affect the pregnancy outcome. The role of blood nutritional parameters requires further clarification. Int. J. Appl. Sci. Biotechnol. Vol 7(2): 248-256  

10 INFLUENCE OF ADMINISTRATION OF HUMAN CHORIONIC GONADOTROPIN ON DAY 4 AFTER FIXED-TIME AI ON CORPUS LUTEUM SIZE, FUNCTION, AND PREGNANCY RATE IN BEEF COWS

2014 ◽  
Vol 26 (1) ◽  
pp. 119
Author(s):  
J. B. S. Borges ◽  
D. X. Thedy
Keyword(s):  
Corpus Luteum ◽  
Pregnancy Rate ◽  
Fixed Time ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Control Group ◽  
Chi Square ◽  
Prostaglandin F2a ◽  
Successful Establishment ◽  
Early Rise

Successful establishment of pregnancy in the cow depends on early rise of progesterone (P4) to improve embryo development. The present study was carried out to determine the corpus luteum (CL) function and pregnancy rate following the administration of 1.500 IU of hCG in suckled beef cows on Day 4 after fixed-time AI (FTAI). Crossbred Angus cows (n = 429), 40 to 70 days postpartum, were synchronized using 2 mg of oestradiol benzoate (EB) i.m. and an intravaginal progesterone-releasing device containing 1 g of P4 for 7 days. At device removal, prostaglandin F2a (150 mg of D-cloprostenol) was injected i.m.; 24 h later, 1 mg of EB was given and the FTAI were done 30 to 36 h after EB using semen of just 1 bull. Cows were assigned alternatively to receive 1.500 IU of hCG i.m. (n = 200) or 1 mL of saline i.m. (n = 229) on Day 4 after FTAI. Ovaries were examined by transrectal ultrasonography (n = 71) on Days 4 and 7 to detect the presence and to measure the area of CL. Blood samples were collected on Days 4, 7, 10, 14, and 30 post-oestrus to determine P4 concentration by RIA. Pregnancy diagnoses were done 30 days after FTAI. The effects of treatments on CL area and serum P4 levels were analysed by ANOVA (Proc GLM, SAS Institute Inc., Cary, NC, USA) and pregnancy rates compared by chi-square (Proc CATMOT, SAS). The induction of accessory CL determined on Day 7 was 44% in cows treated with hCG and not observed in the control group. The area of the CL on Day 7 was significantly higher (P < 0.01; 3.37 ± 2.56 v. 2.56 ± 0.22 cm2) in the hCG group. Despite the increase in CL size, the mean levels of P4 on Days 4, 7, 10, 14, and 30 post-AI indicated no difference (P > 0.05) in CL function between control and hCG-treated cows. On Day 30, pregnancy rates were not different (P = 0.08), at 46.7 and 55% for control and hCG-treated cows, respectively. In conclusion, administration of 1.500 IU of hCG on Day 4 post-FTAI did not improve pregnancy rate in suckled beef cows.

13 THE RELATIONSHIP BETWEEN EARLIER POSTPARTUM CYCLICITY AND SUBSEQUENT REPRODUCTIVE PERFORMANCE IN DAIRY COWS: A FIELD TRIAL

2011 ◽  
Vol 23 (1) ◽  
pp. 113
Author(s):  
I. H. Kim ◽  
H. C. Lee ◽  
H. G. Kang
Keyword(s):  
Dairy Cows ◽  
Body Condition ◽  
Reproductive Performance ◽  
Body Condition Score ◽  
Post Partum ◽  
Management Program ◽  
Breeding Period ◽  
Chi Square ◽  
Logistic Analysis ◽  
The Relationship

Earlier postpartum cyclicity based on hormonal analysis was related to the subsequent fertility, although it has not been clarified under field conditions. This field study examined the relationship between the detection of corpus luteum (CL) at the first post partum month and subsequent reproductive performance in dairy cows. Holstein dairy cows underwent ultrasonography (Sonoace 600 with 7.5 MHz linear-array transducer; Medison Co. Ltd., Korea) at 30 (±7) days postpartum to determine the existence of CL in ovaries and then divided into 2 groups based on the existence of CL; the CL group (n = 156) or the non-CL group (n = 281). At the same time of ultrasonography, all cows were scored for body condition. Cows received the normal herd reproductive management program including oestrous detection or synchronization, or synchronization of ovulation in the breeding period. Pregnancy was determined per rectum 60 days after artificial insemination by both ultrasonography and palpation. Reproductive performance data were collected for a minimum of 210 days postpartum. Reproduction data between the CL and non-CL groups were evaluated by t-test, chi-square test, or logistic regression using an SAS program (Version 9.1: SAS Institute, Inc., Cary, NC, USA). The proportion of cows with CL in ovaries at 30 (±7) days postpartum was 35.7% of all cows. The number of days to first insemination after calving was more delayed (P < 0.0001) in the non-CL group (100.1 ± 2.7 days) than in the CL group (80.9 ± 2.9 days), while the pregnancy rate to first insemination did not differ (P > 0.05) between the CL group (44.2%) and the non-CL group (45.9%). The CL group had higher pregnancy proportions (PP) within 60 (odds ratio, OR = 2.3; P = 0.0063), 90 (OR = 1.6; P = 0.04), and 120 days (OR = 1.5; P = 0.05) postpartum than the non-CL group; however, the PP within 150 or 210 days postpartum did not differ between the 2 groups (P > 0.05). Besides, logistic analysis revealed that cows with body condition score (BCS) ≥3.00 were more likely to have CL (OR = 1.8; P = 0.015) compared with cows with BCS ≤ 2.75, while primiparous cows were less likely to have CL (OR = 0.6; P = 0.0085) compared with multiparous cows. In addition, cows that underwent ultrasonography later than 30 days postpartum were more likely to have CL (OR = 1.6; P = 0.0192) compared with cows that underwent ultrasonography earlier. In conclusion, the earlier cyclicity based on the detection of CL using ultrasonography at the first postpartum month, which might be in part due to a higher BCS, predicts an enhanced reproductive performance in dairy cows, particularly during the early and early-mid lactations. This work was supported by the research grant of the Chungbuk National University in 2010.

Effect of vitamin E on reproductive function in the mice treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin*

2008 ◽  
Vol 24 (9) ◽  
pp. 595-601 ◽  
Author(s):  
JP Xu ◽  
YP Yin ◽  
XQ Zhou
Keyword(s):  
Body Weight ◽  
Vitamin E ◽  
Survival Rate ◽  
Sex Ratio ◽  
Pregnancy Rate ◽  
Reproductive Performance ◽  
Control Group ◽  
Group Iii ◽  
Group I ◽  
Experimental Group

The study was conducted to determine the effects of vitamin E on reproductive performance in mice treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The 75 female and 40 male mice were randomly assigned into five groups. The levels of both TCDD and vitamin E given by gavage were 0 and 0 (Control group), 100 and 0 (experimental group I), 100 and 20 (experimental group II), 100 and 100 (experimental group III), and 100 ng/kg/day and 500 mg/kg/day (experimental group IV), respectively. Males and females were mixed to mate at the ratio of 1:2 after 4-week experiment. The gavage treatments were continued until the end of gestation in female mice after mating. The results showed that the litter number, survival rate, and body weight at birth of offspring in experimental group I had significantly decreased, and the females’ pregnancy rate and pup sex ratio in experimental group I had the decreasing tendencies when compared with the control group. The litter number in experimental group III, survival rate in experimental group II and III, body weight at birth in experimental group III and IV exhibited significant increase compared with experimental group I. The female pregnancy rate in both experimental group III and IV recovered to 100%, but there were no significant differences when compared with experimental group I. The pups’ sex ratio had a gradually increasing tendency with increase of vitamin E level, but there was no significant difference among experimental group I–IV. The results suggest that TCDD could induce reproductive toxicity in mice, whereas vitamin E alleviated adverse effects on reproductive performance in mice caused by TCDD.

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