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1.
J Dairy Sci ; 103(3): 2743-2755, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882220

RESUMO

Our objectives were to test the efficacy of intravaginal (IVG) administration of PGF2α to induce corpus luteum (CL) regression, compare circulating progesterone (P4) profiles in cows receiving IVG versus intramuscular (IM) treatment with PGF2α, and evaluate reproductive outcomes. Lactating Holstein cows were synchronized using a Double-Ovsynch protocol [GnRH, 7 d later PGF2α, 3 d later GnRH, 7 d later GnRH, 7 d later PGF2α, 1 d later PGF2α, 32 h later GnRH, 16 to 20 h timed artificial insemination (TAI)] to receive TAI at 67 ± 3 d in milk. Seven days after the first GnRH treatment (time 0), cows with at least 1 visible CL ≥15 mm were blocked by parity and randomly assigned to a treatment that consisted of IM injection (IM-PGF; n = 201) or IVG instillation (IVG-PGF; n = 201) of PGF2α. Cows in IM-PGF received a single 25-mg dose of PGF2α (dinoprost tromethamine) intramuscularly. Cows in IVG-PGF received two 25-mg doses of PGF2α 12 h apart delivered through a catheter in the cranial portion of the vagina. Blood samples were collected at 0, 12, 48, and 72 h after treatment. Ovulation to the first GnRH of Double-Ovsynch was determined through transrectal ultrasonography. Only cows with P4 ≥1 ng/mL (functional CL) at time 0 (IM-PGF = 169; IVG-PGF = 179) were included in the analyses. Binary and quantitative data were analyzed by logistic regression and ANOVA with repeated measures, respectively. Results are presented as least squares means. Concentrations of P4 and the proportion of cows with a new CL at time 0 did not differ. Overall, the proportion of cows with CL regression using 1 ng of P4/mL (IM-PGF = 89.0%; IVG-PGF = 86.7%) or 0.5 ng of P4/mL (IM-PGF = 82.2%; IVG-PGF = 82.1%) as the cutoff did not differ. Concentrations of P4 were affected by treatment, time, and treatment × time interaction. Cows in IVG-PGF had greater mean P4 at 12 h than cows in IM-PGF. Mean P4 did not differ at 48 or 72 h after treatment. The proportion of cows with estrus recorded within 3 d of treatment (IM-PGF = 45.4%; IVG-PGF = 48.9%), ovulation risk after treatment (IM-PGF = 88.5%; IVG-PGF = 85.1%), and pregnancies per artificial insemination after TAI (IM-PGF = 51.5%; IVG-PGF = 57.8%) did not differ. We concluded that 2 IVG doses of 25 mg of PGF2α 12 h apart were as effective as a single 25-mg IM dose of PGF2α for inducing luteal regression in lactating dairy cattle.


Assuntos
Bovinos/fisiologia , Dinoprosta/análogos & derivados , Luteólise/efeitos dos fármacos , Ocitócicos/administração & dosagem , Reprodução , Administração Intravaginal , Animais , Dinoprosta/administração & dosagem , Estro/efeitos dos fármacos , Sincronização do Estro , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Injeções Intramusculares/veterinária , Inseminação Artificial/veterinária , Lactação , Ovulação/efeitos dos fármacos , Paridade , Gravidez , Progesterona/sangue , Distribuição Aleatória
2.
Reprod Biol Endocrinol ; 17(1): 95, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31744506

RESUMO

BACKGROUND: Polycystic ovary syndrome is characterized by hyperactivity of the ovarian sympathetic nervous system, increases in the content and release of norepinephrine, as well as decreases in the number of ß-adrenoreceptors. In the present study, ß-adrenoreceptors in the ovaries of rats with polycystic ovary syndrome were blocked and analyzed the resultant effects on ovulation, hormone secretion and the enzymes responsible for the synthesis of catecholamines. METHODS: At 60 days of age, vehicle or estradiol valerate-treated rats were injected with propranolol [10- 4 M] into the ovarian bursas on oestrus day. The animals were sacrificed on the next day of oestrus, and the ovulation response, the steroid hormone levels in the serum and the immunoreactivity of tyrosine hydroxylase and dopamine ß-hydroxylase in the ovaries were measured. RESULTS: In animals with the induction of polycystic ovary syndrome and ß-adrenoreceptor blocking, ovulation was restored in more than half of the animals and resulted in decreased hyperandrogenism with respect to the levels observed in the estradiol valerate-treated group. Tyrosine hydroxylase and dopamine ß-hydroxylase were present in the theca cells of the growing follicles and the interstitial gland. Injection of propranolol restored the tyrosine hydroxylase and ovarian dopamine ß-hydroxylase levels in rats with polycystic ovary syndrome induction. CONCLUSIONS: The results suggest that a single injection into the ovarian bursas of propranolol, a nonselective antagonist of ß-adrenoreceptor receptors, decreases the serum testosterone concentration and the formation of ovarian cysts, improving the ovulation rate that accompanies lower levels of tyrosine hydroxylase and dopamine ß-hydroxylase in the ovary.


Assuntos
Ovulação/efeitos dos fármacos , Síndrome do Ovário Policístico/metabolismo , Propranolol/farmacologia , Receptores Adrenérgicos beta/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Animais , Estradiol , Estro/efeitos dos fármacos , Estro/fisiologia , Feminino , Humanos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/fisiopatologia , Ratos , Testosterona/sangue , Tirosina 3-Mono-Oxigenase/metabolismo
3.
Anim Sci J ; 90(12): 1523-1529, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31646735

RESUMO

We aimed to define whether embryo collection carried out after pseudopregnancy was of similar outcome and quality as after artificial abortion. To induce pseudopregnancy, 30 gilts or sows were given 20 mg intramuscular estradiol dipropionate (EDP) 10-11 days after the onset of estrus. Ten additional pigs were inseminated artificially at natural estrus as a control group. Prostaglandin F2α (PGF2α ) was administered twice with a 24 hr interval beginning 15, 20, or 25 days after EDP-treatment (n = 10 per group) or between 23 and 39 days after artificial insemination in control pigs. Following this, all pigs were given 1,000 IU equine chorionic gonadotropin and 500 IU human chorionic gonadotropin (hCG) and then inseminated. Embryos were recovered 6 or 7 days after hCG treatment and outcome was recorded. There was no significant difference in the number of normal embryos collected from the pigs with PGF2α initiated at different time points or from the control group. Embryonic developmental stages 7 days after hCG treatment also did not differ among groups. These results indicate that the use of EDP to induce pseudopregnancy, followed by PGF2α administration to synchronize estrus for subsequent embryo harvest, is a suitable alternative to the artificial abortion method.


Assuntos
Estradiol/análogos & derivados , Estro/efeitos dos fármacos , Pseudogravidez , Criação de Embriões para Pesquisa/métodos , Sus scrofa , Animais , Gonadotropina Coriônica/administração & dosagem , Embrião de Mamíferos , Estradiol/administração & dosagem , Estradiol/farmacologia , Feminino , Prostaglandinas F/administração & dosagem , Prostaglandinas F/farmacocinética
4.
J Dairy Sci ; 102(12): 11730-11735, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629526

RESUMO

The objectives were to evaluate pregnancy per artificial insemination (AI), days to first AI, and proportion pregnant within 7 d of AI eligibility in dairy heifers subjected to presynchronization compared with dairy heifers not presynchronized. Thirty days before AI eligibility, Holstein heifers were assigned randomly to 1 of 3 groups: 14-d controlled internal drug release (CIDR; containing progesterone) presynchronization, PGF2α presynchronization, or control (no presynchronization). Heifers in the 14-d CIDR presynchronization treatment (n = 119) received a CIDR on d -30, which was removed on d -16, followed by an injection of PGF2α upon entry to the breeding program (d 0). Heifers in the PGF2α presynchronization treatment (n = 118) received an injection of PGF2α on d -11 and d 0. Control heifers (n = 121) were not presynchronized and received an injection of PGF2α on d 0. All heifers received tail paint on d 0 to facilitate once-daily detection of estrus (based on paint removal). Heifers detected in estrus received AI with conventional semen on the same morning as detected estrus. Generalized linear mixed models were used to assess mean treatment differences. Following PGF2α treatment on d 0, more heifers were detected in estrus in the first 7 d after eligibility in the 14-d CIDR group (95.8%) compared with the PGF2α (74.6%) and control (66.9%) groups. Days to first AI differed between treatments (14-d CIDR = 3.6 d vs. PGF2α = 5.0 d vs. control = 6.8 d). Pregnancy per AI for first AI within 7 d of eligibility was 71.9% (14-d CIDR), 58.0% (PGF2α), and 61.7% (control), and differed between 14-d CIDR and PGF2α heifers. Presynchronization with a 14-d CIDR increased the proportion of heifers pregnant in the first 7 d of eligibility (14-d CIDR = 68.9% vs. PGF2α = 43.2% vs. control = 41.3%). Projected days on feed (d 0 to projected calving date) were 295 (14-d CIDR), 302 (PGF2α), and 305 (control), and were different between the 14-d CIDR and control heifers. The potential economic benefit to the producer was $15.85 per heifer presynchronized with a 14-d CIDR protocol compared with the control group. Treatment of dairy heifers with a 14-d CIDR effectively presynchronized estrus, resulting in a greater proportion detected in estrus, reduced days to first AI, and an increased proportion of heifers pregnant within the first 7 d after breeding eligibility compared with heifers presynchronized with a single PGF2α injection and control heifers.


Assuntos
Bovinos/fisiologia , Sincronização do Estro/métodos , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Animais , Cruzamento , Dinoprosta/administração & dosagem , Estro/efeitos dos fármacos , Detecção do Estro , Feminino , Inseminação Artificial/veterinária , Gravidez , Taxa de Gravidez , Sêmen
5.
J Anim Sci ; 97(11): 4635-4646, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31563944

RESUMO

This study tested whether supplemental melatonin given to mimic the extended nighttime melatonin pattern observed in the higher fertility winter season could minimize infertility during summer and fall in swine. Exogenous melatonin was fed during periods coinciding with follicle selection, corpus luteum formation, pregnancy recognition, and early embryo survival. Experiments were conducted at a commercial farm in 12 sequential replicates. In Exp. 1a, mature gilts (n = 420) that had expressed a second estrus were assigned by weight to receive once daily oral Melatonin (MEL, 3 mg) or Control (CON, placebo) at 1400 h for 3 wk starting before insemination at third estrus. In Exp. 1b, parity 1 sows (n = 470) were randomly assigned by lactation length to receive MEL or CON for 3 wk, starting 2 d before weaning. Follicles, estrus, pregnancy, and farrowing data were analyzed for the main effects of treatment, season (4-wk periods), and their interaction. Environmental measures were also analyzed for reproductive responses. In Exp. 1a, there was no effect (P > 0.10) of MEL on age at third estrus (203 d), follicle size after 7 d of treatment (5.0 mm), estrous cycle length (22.6 d), return to service (9.2%), farrowing rate (FR, 80.0%), or total born pigs (TB, 13.6). However, there was an effect of season (P = 0.03) on number of follicles and on gilts expressing estrus within 23 d of the previous estrus (P < 0.005). In Exp. 1b, there was no effect of MEL (P > 0.10) on follicle measures, wean to estrous interval, FR (84.0%), or TB (13.0). But MEL (73.5%) reduced (P = 0.03) estrous expression within 7 d of weaning compared with CON (82.0%) and season (P = 0.001) decreased FR by ~14.0% during mid summer. Also, gilts and parity 1 sows exposed to low light intensity (<45 lx) during breeding had reduced conception (-8%) and farrowing (-15%) rates, compared with higher light intensity. Similarly, high temperatures (>25 °C) during breeding also reduced gilt conception rates by 7%. Although there was clear evidence of seasonal fertility failures in gilts and sows, MEL treatment did not improve fertility in gilts and reduced estrus in parity 1 sows. It is possible that differences in lighting and thermal environments before breeding could explain the differential response to MEL in sows and gilts.


Assuntos
Fertilidade/efeitos dos fármacos , Melatonina/administração & dosagem , Reprodução , Suínos/fisiologia , Animais , Cruzamento , Estro/efeitos dos fármacos , Feminino , Lactação/efeitos dos fármacos , Luz , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Paridade/efeitos dos fármacos , Gravidez , Estações do Ano
6.
J Vet Med Sci ; 81(11): 1685-1687, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31548470

RESUMO

We examined the effect of human chorionic gonadotropin (hCG) treatment on double ovulation rate of first-wave follicles five days after estrus in lactating dairy cows. Cows were divided into two groups: 1) Ipsilateral group (IG; n=35), in which the first-wave dominant follicle (DF) was ipsilateral to the corpus luteum (CL), and 2) Contralateral group (CG; n=30), in which the first-wave DF was contralateral to the CL five days after estrus, then 1,500 IU of hCG was administrated. Double ovulation rate was significantly higher in the CG (26.7%) than in the IG (2.9%). This study demonstrate that the double ovulation rate of first-wave follicles was higher in the first-wave DF located in the contralateral ovary to the CL.


Assuntos
Bovinos , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/fisiologia , Estro/fisiologia , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Animais , Estro/efeitos dos fármacos , Feminino , Lactação , Folículo Ovariano/fisiologia , Ovulação/fisiologia
7.
Theriogenology ; 140: 8-17, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421533

RESUMO

OBJECTIVES: were to determine effects of 1) injectable or transdermal flunixin meglumine (FM) at embryo transfer (ET) compared to an untreated control group on pregnancy per ET (P/ET; ∼35 d after ET); 2) embryo and recipient factors on P/ET; 3) FM on hormone concentrations; and 4) FM on returns to estrus. Angus-cross beef cows (n = 1145) at five locations were scored for body condition (BCS; 1-9) and temperament (0 or 1) and given Select-Synch + CIDR. Recipient cows with a corpus luteum (CL) ≥1.5 cm received a frozen-thawed embryo 7 d after estrus and were concurrently given 1.1 mg/kg injectable FM im (INJFM; n = 384), 3.3 mg/kg transdermal FM pour on (TDFM; n = 388), or nothing (CON group; n = 373). Blood samples were collected at ET and 7 d later (60 cows). Accounting for temperament (P < 0.05), ET difficulty score (1-3, easy to difficult; P < 0.01), treatment by temperament (P < 0.001) and treatment by embryo quality (P < 0.05), FM treatments affected P/ET (P < 0.05). The P/ET for cows given INJFM [62.8% (241/384)] or TDFM [58.7% (228/388)] were not different (P = 0.26), but they were greater (P = 0.01 and P = 0.04, respectively) than P/ET for controls [51.2% (191/373)]. The P/ET was greater for calm versus excitable cows, 60.2 (463/769) and 52.4% (197/376), respectively (P < 0.01) and was lower for difficulty score 3 [49.2% (156/317)] compared to score 1 [62.7% (254/405; P < 0.001) or score 2 [59.1% (250/423; P < 0.01)]. There was no effect (P > 0.1) of cow age, BCS, or stage of embryo development on P/ET. Pregnancy rates for embryo quality grade 1 (excellent/good) and grade 2 (fair) were 60.4% (314/520) and 55.4% (346/625), respectively (P > 0.05). Percentages of non-pregnant recipient cows in estrus from Days 18-26 did not differ among treatment groups (P > 0.1). Control cows had lower progesterone concentrations and greater substance-P, PGFM and 8-isoprostane PGF2α concentrations at 7 d after ET compared to FM-treated cows (P < 0.05). In conclusion, injectable or transdermal FM improved pregnancy rates in ET recipients, without affecting nonpregnant cows return to estrus.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Bovinos , Clonixina/análogos & derivados , Transferência Embrionária/veterinária , Animais , Anti-Inflamatórios não Esteroides/efeitos adversos , Clonixina/efeitos adversos , Clonixina/farmacologia , Transferência Embrionária/métodos , Estro/efeitos dos fármacos , Feminino , Hidrocortisona/sangue , Gravidez , Taxa de Gravidez , Progesterona/sangue , Prostaglandinas/sangue , Substância P/sangue
8.
J Reprod Dev ; 65(5): 451-457, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31406064

RESUMO

This study aimed at investigating the efficacy of two protocols of estrous synchronization on follicular changes and hemodynamics. Pluriparous Egyptian buffaloes (n = 36) were synchronized either with controlled internal drug release (CIDR)-PGF2α (7-days CIDR insert with PGF2α injected on the 6th day; n = 18) or Ovsynch-CIDR (Ovsynch protocol concurrent with 7-days CIDR insert; n = 18). Blood sampling and ovarian ultrasound examinations (Grayscale, color and power Doppler modes) were conducted on the Day of CIDR removal, estrus, and luteal phase. Mean follicle diameter (MFD), first (1st-LF) and second (2nd-LF) largest follicle diameters, and E2 levels significantly increased in the CIDR-PGF2α group at CIDR withdrawal. Ovsynch-CIDR markedly fortified higher follicle population, MFD, and 1st-LF diameter at estrus and corpus luteum (CL) volume at the luteal phase in concomitant with increases (P < 0.05) in E2 (at estrus) and P4 (at luteal phase). At CIDR removal, the blue pixels in the dominant follicle (DF) were higher (1.5 times; P = 0.054) in the Ovsynch-CIDR than in the CIDR-PGF2α. At estrus, total blood flow (TBF) and power Doppler pixels (PDP) to DF(s) were noticeably higher (seven and 1.6 times; respectively) in the Ovsynch-CIDR than in CIDR-PGF2α (5906 ± 237 vs. 830 ± 60 pixels, P < 0.01 and 5479 ± 322 vs. 3377 ± 19 pixels, P < 0.05; respectively). At the luteal phase, TBF and PDP to the CL increased in the Ovsynch-CIDR group than in the CIDR-PGF2α group (11060 ± 965 vs. 7963 ± 480 pixels, 1.4 times, P = 0.05 and 18900 ± 1350 vs. 13220 ± 568 pixels, 1.1 times, P = 0.005; respectively). In conclusion, based on the improvement in synchronized follicular activity and hemodynamics, the Ovsynch-CIDR regimen is persuaded in Egyptian buffaloes.


Assuntos
Dinoprosta/administração & dosagem , Sincronização do Estro/métodos , Inseminação Artificial/veterinária , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Animais , Cruzamento , Búfalos , Ciclo Estral/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Hemodinâmica , Fase Luteal/efeitos dos fármacos , Folículo Ovariano/diagnóstico por imagem , Esteroides/sangue , Ultrassonografia Doppler
9.
Reprod Domest Anim ; 54(11): 1489-1492, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31355955

RESUMO

The present study supports that 5-day short-term CIDR treatments without administration of eCG are equally effective for inducing oestrus behaviour, preovulatory LH discharge and ovulation in sheep than classical protocols based on 14-day treatments plus eCG at CIDR withdrawal. However, the implementation of a 5-day protocol without eCG for fixed-time artificial insemination would be adapted to a later timing of ovulation (p < .05).


Assuntos
Estro/efeitos dos fármacos , Gonadotropinas Equinas/farmacologia , Progesterona/farmacologia , Administração Intravaginal , Animais , Sincronização do Estro/metabolismo , Feminino , Gonadotropinas Equinas/administração & dosagem , Ovulação , Indução da Ovulação/métodos , Indução da Ovulação/veterinária , Progesterona/administração & dosagem , Ovinos
10.
J Anim Sci ; 97(9): 3617-3625, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31298271

RESUMO

Supplemental arginine (Arg) during gestation purportedly benefits fetal development. However, the benefits of a gestational Arg dietary strategy in commercial production are unclear. Therefore, the objectives of this study examined Arg supplementation during different gestational stages and the effects on gilt reproductive performance. Pubertal gilts (n = 548) were allocated into 4 treatment groups: Control (n = 143; 0% supplemental Arg) or 1 of 3 supplemental Arg (1% as fed) treatments: from 15 to 45 d of gestation (n = 138; Early-Arg); from 15 d of gestation until farrowing (n = 139; Full-Arg); or from 85 d of gestation until farrowing (n = 128; Late-Arg). At farrowing, the number of total born (TB), born alive (BA), stillborn piglets (SB), mummified fetuses (MM), and individual piglet birth weights (BiWt) were recorded. The wean-to-estrus interval (WEI) and subsequent sow reproductive performance (to third parity) were also monitored. No significant effect of supplemental Arg during any part of P0 gestation was observed for TB, BA, SB, or MM (P ≥ 0.29). Offspring BiWt and variation among individual piglet birth weights did not differ (P = 0.42 and 0.89, respectively) among treatment groups. Following weaning, the WEI was similar among treatments (average of 8.0 ± 0.8 d; P = 0.88). Litter performance over 3 parities revealed a decrease (P = 0.02) in BA for Early-Arg fed gilts compared with all other treatments, whereas TB and WEI were similar among treatments over 3 parities (P > 0.05). There was an increased proportion of sows with average size litters (12 to 16 TB) from the Full-Arg treatment sows (76.8% ± 3.7%) when compared with Control (58.7% ± 4.2%; P = 0.01); however, the proportion of sows with high (>16 TB) and low (<12 TB) litters was not different among treatments (P = 0.20). These results suggest that gestational Arg supplementation had a minimal impact on reproductive performance in first parity sows. These data underscore the complexity of AA supplementation and the need for continued research into understanding how and when utilizing a gestational dietary Arg strategy can optimize fetal development and sow performance.


Assuntos
Arginina/farmacologia , Suplementos Nutricionais , Reprodução , Suínos/fisiologia , Animais , Peso ao Nascer/efeitos dos fármacos , Dieta/veterinária , Estro/efeitos dos fármacos , Feminino , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Paridade/efeitos dos fármacos , Parto/efeitos dos fármacos , Gravidez , Desmame
11.
J Anim Sci ; 97(7): 2965-2971, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31119289

RESUMO

An experiment was conducted with 430 sows to evaluate the ideal standardized ileal digestible (SID) Val:Lys on sow and litter performance during an 18.6-d lactation period. The SID Val:Lys ratios measured were based on the previously published literature and then values above and below reported values. Sows were randomly allotted within parity block (parity 1, parity 2, and parity 3+) to one of five corn-soybean meal-based lactation diets formulated to contain different levels of SID Val:Lys (0.50, 0.62, 0.75, 0.88, and 1.00, respectively). All diets were formulated to be isocaloric (3.35 ME Mcal/kg) with 0.95% SID Lys and contained vitamins and minerals that exceeded recommendations (NRC, 2012). Experimental diets were given to sows from 112 d of pregnancy throughout the 23-d lactation period. Litters were standardized within 48 h after farrowing. Sows were fed with the Howema computerized feeding system that mixed the high and low diets to create the intermediate diets, weighed the feed for each sow and then delivered the feed to each individual feeding hopper to record daily sow feed intake during lactation. Data were analyzed as a randomized complete block design using the PROC MIXED procedure of SAS with sow as the experimental unit and treatment as a fixed effect and parity as the random effect. Results were considered significant at P ≤ 0.05 and considered a trend at P > 0.05 and P ≤ 0.10. Sow ADFI was not significantly different (5.2, 5.2, 5.2, 5.0, and 5.4 ± 0.15 kg/d, respectively). On average, sows consumed ~45 g of SID Lys per day. Sow wean to estrus (5.2, 4.7, 5.3, 5.5, and 4.5 ± 0.32 d, respectively) was not different as the Val:Lys ratio changed. Increasing the Val:Lys ratio resulted in no differences (2.66, 2.64, 2.76, 2.61, and 2.62 ± 0.08 kg; P > 0.10) in average daily litter gain. There were no differences in sow weight loss or subsequent total born across the dietary treatments. Overall, increasing levels of SID Val:Lys did not change sow reproductive performance or piglet growth rate.


Assuntos
Ração Animal/análise , Lisina/análise , Reprodução/efeitos dos fármacos , Valina/análise , Animais , Dieta/veterinária , Estro/efeitos dos fármacos , Feminino , Lactação/efeitos dos fármacos , Paridade/efeitos dos fármacos , Gravidez , Distribuição Aleatória , Soja , Suínos , Desmame
12.
Reprod Domest Anim ; 54(7): 1003-1009, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31058368

RESUMO

The efficacy of eight combinations of fluorogestone acetate (FGA, 20 or 40 mg as intravaginal device during 11 days), equine chorionic gonadotropin (eCG, 300 or 500 UI injected 48 hr before FGA removal) and prostaglandin F2α (cloprostenol, 0 or 50 µg injected 48 hr before FGA removal) aiming at induction and synchronization of oestrus and ovulation was evaluated during the anoestrus season in spring and during the breeding season in autumn in adult Beni Arouss goats. Oestrous behaviour was recorded between 12 and 60 hr after FGA removal. Blood samplings allowing to assess onset of the pre-ovulatory LH surge and increase of progesterone as sign of an active corpus luteum were performed, respectively, between 20 and 60 hr and 3, 5, 8 and 15 days after FGA removal. No season-related differences (spring vs. autumn) were observed for oestrous response (95% vs. 93%), pre-ovulatory LH surge (94% vs. 84%) and luteal response after 3-8 and 11-15 days post-treatment (respectively 92% vs. 66% and 92% vs. 98%). The onset of oestrus (21 [13-53] vs. 32 [12-54] hr) and LH surge (26 [20-60] vs. 38 [22-60] hr) occurred significantly later in autumn. FGA (40 vs. 20 mg) in autumn significantly delayed the onset of oestrus (36 [16-54] vs. 23 [12-47] hr) and LH surge (44 [26-58] vs. 33 [22-60] hr). Significant treatment-related differences were recorded for onset of LH surge (earliest for 20 mg FGA, 300 IU eCG, 50 µg PGF2α ) and onset of luteal phase (latest for 40 mg FGA, 300 IU eCG, 50 µg PGF2α ). In conclusion, the hormone combinations tested appeared equally effective in terms of oestrous and ovulation rates. Season has influenced significantly the onset of oestrus and LH surge, and the high dose regimen of FGA delayed the ovarian response in autumn.


Assuntos
Sincronização do Estro/efeitos dos fármacos , Cabras/fisiologia , Ovulação/efeitos dos fármacos , Animais , Cloprostenol/administração & dosagem , Estro/efeitos dos fármacos , Feminino , Acetato de Fluorogestona/administração & dosagem , Gonadotropinas Equinas/administração & dosagem , Hormônio Luteinizante/sangue , Luteolíticos/administração & dosagem , Progesterona/sangue , Progestinas/administração & dosagem , Estações do Ano
13.
Animal ; 13(10): 2305-2312, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30982488

RESUMO

Expression of estrus near timed artificial insemination (TAI) is associated with greater fertility, and estrus detection could improve TAI fertility or direct TAI management, although accurate estrus detection can be difficult and time-consuming using traditional methods. The aim of this study is to evaluate influence of estrus on pregnancy (artificial insemination pregnancy rates (P/AI)) and to validate an alternative method to classify estrus/heat expression using tail chalking (HEATSC) in postpartum Bos indicus cows subjected to TAI in progesterone-estrogen-based protocols. In experiment 1 (Exp. 1), cows (5491) were subjected to visual observation of estrus after progesterone device removal, before TAI, and P/AI was evaluated according to estrus and body condition score (BCS). Cows received a progesterone device and 2 mg estradiol benzoate (EB). After 8 days, the device was removed and 150 µg of d-cloprostenol and 300 IU equine chorionic gonadotrophin was given. Later, animals in Exp. 1 received 1 mg EB and TAI 44 to 48 h. In the Exp. 2 - 3830 cows using similar protocol, received different ovulation inducers: 1 mg EB (n=1624) or 1 mg estradiol cypionate (EC; n=2206) on day 8 (D8). Cows were then marked with chalk, and HEATSC evaluated at TAI on D10 (HEATSC1 - no chalk removal=no estrus expression; HEATSC2 - partial chalk removal=low estrus expression; HEATSC3 - near complete/complete chalk removal=high estrus expression). In Exp. 1, cows showing estrus presented greater P/AI (48.4% v. 40.2%, P<0.05). In Exp. 2, P/AI (HEATSC1 - 40.0%; HEATSC2 - 49.7%; HEATSC3 - 60.9%; P<0.001), and larger follicle timed artificial insemination (LFTAI) (<0.001) varied according to HEATSC. There was no difference in P/AI (P=0.41) or LFTAI (P=0.33) according to ovulation inducer. Cows with greater BCS showed greater P/AI in both experiments (P<0.05). Estrus presence and greater HEATSC improved P/AI, and EC v. EB used promoted differential estrus manifestation (cows showing HEATSC2 and HEATSC3: 79.5% with EB v. 69.98% with EC use, P<0.001), however, with similar P/AI. The use of HEATSC in B. indicus cows subjected to TAI is useful to identify cows with greater estrus expression and consequently improved pregnancy rates in TAI, allowing the cows with low HEATSC to be targeted for additional treatments aimed at improving P/AI.


Assuntos
Bovinos/fisiologia , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Progesterona/administração & dosagem , Reprodução/efeitos dos fármacos , Animais , Estro/efeitos dos fármacos , Detecção do Estro , Feminino , Fertilidade/efeitos dos fármacos , Temperatura Alta , Inseminação Artificial/veterinária , Folículo Ovariano/efeitos dos fármacos , Indução da Ovulação , Gravidez , Taxa de Gravidez
14.
Theriogenology ; 132: 113-117, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009915

RESUMO

In Jordan, the Arabian Oryx (Oryx leucoryx) is considered among the most important wild ungulates. The Arabian Oryx is listed as vulnerable species according to the International Union for Conservation of Nature (IUCN). Based on author's knowledge, estrus synchronization in the Arabian Oryx has never been investigated. Therefore, the current study aimed to validate a Controlled Internal Drug Release (CIDR) estrus synchronization technique for the first time in 7 Arabian Oryx females. Prior to CIDR application, animals were subjected to transabdominal ultrasonic examination twice, two weeks apart to exclude pregnancies. A single CIDR was inserted (Day 0) for a period of 7 days. At the time of CIDR removal (Day 7), animals were administered a single injection of prostaglandin F2α (PF2α) and equine chorionic gonadotropin (eCG). Blood samples were collected from all animals before, during and after CIDR removal for progesterone (P4) analysis. Animals were monitored for estrus behavior for 8 days starting 24 h after CIDR removal. All animals were considered to be anestrous at the start of the study as defined by having blood progesterone <1 ng/ml prior to insertion of the CIDR. All animals displayed estrous behavior between Day 1-3 after CIDR removal and the average interval from CIDR removal to estrus and length of estrus were 53.71 ±â€¯5.59 h and 55.43 ±â€¯6.19 h, respectively. On Day 14 (6 days after CIDR removal) P4 concentrations rose above 1 ng/ml indicated ovulation. It is possible to synchronize estrus in Arabian Oryx using CIDRs. The success of CIDR estrous synchronization in female Arabian Oryx, as described in the current study, opens new perspectives towards the possible application of assisted reproductive techniques for the propagation and conservation englishEnglishof this vulnerable species.


Assuntos
Antílopes/fisiologia , Gonadotropina Coriônica/farmacologia , Sincronização do Estro , Estro/efeitos dos fármacos , Administração Intravaginal , Animais , Gonadotropina Coriônica/administração & dosagem , Estro/fisiologia , Feminino , Progesterona/sangue
15.
J Dairy Sci ; 102(7): 6649-6659, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31030926

RESUMO

Dinoprost tromethamine (DIN), a molecule similar to endogenous PGF2α, has a half-life of approximately 9 min. Cloprostenol sodium (CLO), a synthetic analog of PGF2α, has a half-life of approximately 3 h. We hypothesized that treatment of Holstein heifers with CLO would improve estrous detection rate, estrous characteristics, service rate, and overall reproductive performance compared with DIN. Currently in the United States, heifers are largely inseminated based on signs of estrus, which is detected visually or with the aid of mounting detection devices (MD). Automated estrous detection devices (AED) are becoming more accessible to producers, but it is not clear whether they present advantages in the reproductive management of heifers. Therefore, we hypothesized that the use of an AED would improve service and pregnancy rates compared with detection of estrus with the aid of a MD. Holstein heifers (n = 1,019) were enrolled in the experiment at 10 to 11 mo of age, when they were fitted with a Heatime HR LD System (SCR Ltd., Netanya, Israel). At 12 mo of age, we paired heifers according to estrous cycle phase and randomly assigned them to treatments in a 2 × 2 design: PGF2α formulation (CLO vs. DIN) and estrous detection treatment (AED vs. MD). Heifers in the AED treatment were detected in estrus only by the Heatime HR LD System, whereas heifers in the MD treatment were detected in estrus only by the Kamar Heatmount Detector (Kamar Products Inc., Zionsville, IN). Treatments with the same PGF2α formulations were repeated 14 d after the first treatment if heifers had not been detected in estrus. A sub-group of heifers had blood sampled on the day of PGF2α treatment and within 24 h of onset of estrus to determine progesterone and estradiol concentrations. Treatment with CLO reduced the progesterone concentration within 24 h of onset of estrus compared with DIN (0.04 ± 0.01 vs. 0.11 ± 0.01 ng/mL). Among heifers in mid diestrus on the day of PGF2α treatment, CLO reduced the interval to estrus compared with DIN (72.0 ± 2.2 vs. 82.4 ± 2.4 h). Prostaglandin F2α formulation and estrous detection treatment did not affect pregnancy to the first service. The interval between the first and second services tended to be reduced for the AED treatment compared with the MD treatment (24.4 ± 0.5 vs. 25.7 ± 0.6 d). Prostaglandin F2α formulation and estrous detection treatment did not affect the hazard of pregnancy. Although CLO treatment may shorten the interval to estrus in heifers at mid diestrus compared with DIN, PGF2α formulation did not affect reproductive performance. In the current experiment, no advantages in reproductive performance were observed when estrous detection was based on an AED compared with a MD.


Assuntos
Bovinos/fisiologia , Cloprostenol/farmacologia , Detecção do Estro , Estro/efeitos dos fármacos , Taxa de Gravidez , Animais , Dinoprosta/análogos & derivados , Dinoprosta/farmacologia , Feminino , Inseminação Artificial/veterinária , Gravidez , Progesterona/sangue , Distribuição Aleatória , Reprodução
16.
Animal ; 13(10): 2313-2318, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30915942

RESUMO

The use of tail chalk and estrus/heat expression scores (HEATSC) evaluation is instrumental in identifying cows with greater estrus expression and greater artificial insemination pregnancy rates (P/AI) in cows submitted to timed artificial insemination (TAI), and cows with low or no estrus expression present lower P/AI. It was intended in this study to improve the pregnancy rates in TAI for Bos indicus beef cows, and gonadotrophin-releasing hormone (GnRH) injection was hypothesized to increase pregnancy rates in a TAI program for cows submitted to progesterone-estradiol-based protocols with low or no estrus expression, evaluated by HEATSC. Cows (n= 2284) received a progesterone device and 2 mg estradiol benzoate, after 8 days the device was removed and 1 mg estradiol cypionate, 150 µg of d-cloprostenol and 300 IU equine chorionic gonadotropin was administered. All cows were marked with chalk and HEATSC evaluated (scales 1 to 3) at TAI performed on day 10. Animals with HEATSC1 and HEATSC2 (n= 937) received 100 µg de gonadorelin (GNRH group; n= 470), or 1 ml saline (Control group; n= 467), and cows with HEATSC3 (named HEAT group; n= 1347) received no additional treatment. The larger dominant follicle, evaluated on day 8and at TAI (day 10), was greater in HEAT group (P= 0.0145 and P <0.001, respectively). Corpus luteum (CL) area and progesterone concentration was evaluated on day 17, and CL area was larger in HEAT group, intermediary in Control and lower in GnRH group (Control= 2.68 cm2, GnRH= 2.37 cm2, HEAT group= 3.07 cm2, P <0.001). Greater progesterone concentrations were found in HEAT group than in Control and GnRH groups (Control= 4.74 ng/ml, GnRH= 4.29 ng/ml, HEAT group= 6.08 ng/ml, P<0.001). There was a difference in ovulation rate, greater in HEAT group than GnRH and Control groups (Control= 72.5%; GnRH= 81.25%; HEAT group= 90.71%; P= 0.0024). Artificial insemination pregnancy rates was greater in HEAT group (57.09% (769/1347) than in Control and GNRH groups, with positive effect of GnRH injection at the time of TAI in P/AI (Control= 36.18% (169/467), GnRH= 45.95% (216/470); P<0.0001). In conclusion, GnRH application in cows with low HEATSC (1 and 2) is a simple strategy, requiring no changes in TAI management to increase pregnancy rates in postpartum beef cows submitted to progesterone-estradiol-based TAI protocols, without reaching, however, the pregnancy rates of cows that demonstrate high estrus expression at the TAI.


Assuntos
Bovinos/fisiologia , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Progesterona/administração & dosagem , Reprodução/efeitos dos fármacos , Animais , Corpo Lúteo/efeitos dos fármacos , Estro/efeitos dos fármacos , Detecção do Estro , Feminino , Fertilidade/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/administração & dosagem , Temperatura Alta , Inseminação Artificial/veterinária , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Indução da Ovulação , Gravidez , Taxa de Gravidez
17.
J Chin Med Assoc ; 82(3): 231-234, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30908416

RESUMO

BACKGROUND: This study was designed to evaluate the antifertility efficacy of eugenol (EUG) and Ocimum sanctum (OS) leaf extract in female albino rats. METHODS: The healthy female albino rats were administered with EUG (99% pure) at a dose of 0.4 ml/day/rat and OS Linn. (Tulsi) leaf extract at a dose of 500 mg/kg body weight/day/rat orally for 15 days. One-way ANOVA analysis with Dunnetts multiple comparison test is used for analyzing data. RESULTS: The total duration of estrous cycle was prolonged with EUG and no significant changes with OS leaf extract administration were observed. EUG elevated serum estradiol and progesterone levels but OS leaf extract elevates only progesterone levels. Elevated ovarian proteins were observed in both administrations. CONCLUSION: This study concludes that the administration of EUG and OS leaf extract significantly enhanced the serum estradiol and progesterone levels leading to reduced frequency of ovulation and results in the impairment of fertility.


Assuntos
Eugenol/farmacologia , Fertilidade/efeitos dos fármacos , Ocimum sanctum , Extratos Vegetais/farmacologia , Animais , Estradiol/sangue , Estro/efeitos dos fármacos , Feminino , Folhas de Planta , Progesterona/sangue , Ratos , Ratos Wistar
18.
Trop Anim Health Prod ; 51(6): 1763-1765, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30827002

RESUMO

The goal of this study was to assess the efficacy of the re-utilization of an ear implant impregnated with norgestomet on estrus synchronization response and pregnancy rates in sheep. Fifty-five Texel ewes were classified according to body condition (3.5) and live weight (65 kg), and randomly assigned to two experimental groups: NORN-new (n = 30) and NORU-used (n = 25). The dose of norgestomet used in the treatments was half of that recommended for bovine (1.5 mg). The synchronization protocol consisted of an ear implant inserted on day 0 (beginning of the experiment) and kept for 6 days. The removal of the implant on day 6 was followed by an injection of a prostaglandin analogue (0.263 mg) and eCG (250 IU). Rams with paint applied to their chest were used to facilitate estrus detection for 5 days following implant withdrawal. Estrus behavior was observed in 93.3% (28/30) and 90% for NORN and NORU, respectively. Pregnancy rates for NORN were 73.3% and for NORU were 68%. Estrus behavior and pregnancy rates between treatment groups did not differ statistically. Therefore, the re-utilization of ear implants impregnated with norgestomet, in addition to eCG and a prostaglandin analogue in short-term estrus synchronization protocols, allow acceptable estrus response and pregnancy rates in sheep.


Assuntos
Implantes de Medicamento/farmacologia , Sincronização do Estro/métodos , Estro/efeitos dos fármacos , Pregnenodionas/farmacologia , Ovinos , Animais , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/farmacologia , Implantes de Medicamento/administração & dosagem , Detecção do Estro , Feminino , Gravidez , Pregnenodionas/administração & dosagem , Progestinas/administração & dosagem , Progestinas/farmacologia , Prostaglandinas/administração & dosagem , Prostaglandinas/farmacologia , Distribuição Aleatória
19.
Am J Vet Res ; 80(3): 306-310, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30801209

RESUMO

OBJECTIVE To evaluate use of flunixin meglumine as a treatment to postpone ovulation in mares, mare fertility after flunixin meglumine treatment during estrous cycles, and effects of flunixin meglumine on function of the corpus luteum after ovulation. ANIMALS 13 healthy mares. PROCEDURES A single-blinded, placebo-controlled, crossover study was conducted. Flunixin meglumine (1.1 mg/kg, IV, q 24 h) or lactated Ringer solution (placebo treatment) was administered for 2 days to mares with a dominant follicle (≥ 35 mm in diameter) and behavioral signs of estrus. Mares then were bred by artificial insemination. Number of days to ovulation from initial detection of a follicle ≥ 30 mm in diameter, uterine edema score, and pregnancy were determined by ultrasonography; the examiner was unaware of the treatment of each mare. Serum progesterone concentrations were evaluated 5 and 12 days after ovulation by use of radioimmunoassay. RESULTS Data were available for 45 estrus cycles of the 13 mares. Number of days to ovulation from initial detection of a follicle ≥ 30 mm was not significantly affected by administration of flunixin meglumine versus the placebo. Per-cycle pregnancy rate was not significantly different between flunixin meglumine (20/24 [83%] breedings) and the placebo (13/19 [68%] breedings). Flunixin meglumine did not significantly affect behavioral signs of estrus, uterine edema, or serum progesterone concentrations. CONCLUSIONS AND CLINICAL RELEVANCE Findings did not support the use of flunixin meglumine to postpone ovulation in mares.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Clonixina/análogos & derivados , Cavalos , Ovulação/efeitos dos fármacos , Animais , Clonixina/farmacologia , Corpo Lúteo/efeitos dos fármacos , Estudos Cross-Over , Ciclo Estral/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Inseminação Artificial/veterinária , Gravidez , Progesterona , Método Simples-Cego
20.
J Anim Sci ; 97(4): 1456-1467, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30772895

RESUMO

Fescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue. The objective of this study was to evaluate the impact of the slick hair trait on physiological and reproductive parameters in heifers experiencing fescue toxicosis. Angus × Senepol heifers (n = 31) were blocked by weight (393.5 ± 17.3 kg) and phenotype relative to hair coat at birth, and randomly fed novel endophyte fescue (EN) or endophyte-infected fescue (EI) haylage in a total mixed ration for 91 d. Weekly measurements were collected to monitor heifer growth and response during ergot alkaloids exposure. Following 28 d of treatment, estrus was synchronized and heifers were inseminated. Ovary mapping and AI pregnancy rate were examined via transrectal ultrasonography. Blood samples were taken for genotyping: slick (S) or wildtype (W). Data were analyzed using repeated measures in PROC MIXED of SAS including fescue treatment (EN vs. EI), genotype (S vs. W), and sample collection time as main effects. Body condition scores were decreased for W heifers compared with S heifers (5.48 vs. 5.66, respectively; P < 0.0001). Surface temperature was greater for EI-W heifers (37.2 °C) compared with other groups (36.4, 36.6, 36.7 °C for EN-S, EN-W, EI-S, respectively; P < 0.05). Serum PRL concentrations were reduced for EI heifers compared with EN heifers (133.5 vs. 163.1 ng/mL, respectively; P < 0.05). The average number of 2 to 4 mm follicles were greater in EI-W heifers (13.8 follicles) compared with other groups (12.2, 10.6, and 11.1 for EN-S, EN-W, and EI-S, respectively; P < 0.0001). However, the average number of preovulatory follicles (≥9 mm) were reduced in EI-W heifers (0.52 follicles) compared with other heifer groups (0.94, 0.88, and 0.85 ± 0.04 for EN-S, EN-W, and EI-S, respectively; P < 0.05). Ovulatory follicle size was smaller in EI-W heifers compared with EN-W heifers (9.14 vs. 11.57 mm, respectively; P = 0.05). Corpus luteum area was reduced in EI-W heifers (235.1 mm2) compared with other heifer groups (297.2, 272.7, and 276.8 mm2 for EN-S, EN-W, and EI-S, respectively; P < 0.05). Concentrations of P4 were greater for EN heifers compared with EI heifers (2.7 vs. 1.8 ng/mL, respectively; P < 0.05). Pregnancy was not established in EI-W heifers (0%) compared with other heifer groups (37.5%, 57.1%, and 62.5% for EN-S, EN-W, and EI-S, respectively; P < 0.05). Overall, the slick hair mutation appears to aid in offsetting the physiological symptoms associated with fescue toxicosis and helps to improve reproductive performance.


Assuntos
Bovinos/fisiologia , Endófitos/fisiologia , Alcaloides de Claviceps/efeitos adversos , Festuca/microbiologia , Reprodução/efeitos dos fármacos , Ração Animal/análise , Animais , Peso Corporal/efeitos dos fármacos , Corpo Lúteo/fisiologia , Dieta/veterinária , Estro/efeitos dos fármacos , Feminino , Cabelo , Folículo Ovariano/fisiologia , Ovário/fisiologia , Fenótipo , Gravidez , Distribuição Aleatória
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