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1.
Reprod Domest Anim ; 53(2): 484-494, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29352501

RESUMEN

Two experiments were conducted to determine (i) factors influencing calf temperament at weaning, (ii) association between heifer-calf temperament at weaning and temperament at breeding and (iii) effect of heifer-calf temperament on pregnancy rate per artificial insemination (P/AI). In experiment 1, beef cows and their calves (n = 285) from three farms were used. Sire docility estimated progeny difference (EPD) score, birth type (normal or assisted), calf gender, calf behaviour (during 1st 4 weeks) and calf health status (until weaning) were recorded. Cows and calves were assigned a temperament score (0-calm; 1-excitable), and all cows were given a body condition score (BCS, 1-9; 1-emaciated; 9-obese) at weaning. Calf's illness (p < .05), low sire docility EPD score (p < .05), altered gait (p < .05), altered resting behaviour (p < .01), reduced/no play behaviour (p < .05) and cow excitable temperament (p < .001) increased calf excitable temperament at weaning. In experiment 2, replacement heifer-calves (n = 758) from 12 farms were assigned a temperament score at weaning and later at breeding. Blood from 40 calves at weaning and 31 heifers at initiation of synchronization (same animals) was collected by coccygeal venipuncture for determination of circulating cortisol and substance P concentrations. Heifers were assigned a BCS and reproductive tract score (RTS, 1-5; 1-immature, acyclic; 5-mature, cyclic), synchronized for fixed time AI, observed for oestrus and were artificially inseminated. Cortisol concentrations were increased in excitable heifer-calves compared to calm heifer-calves at weaning (p < .05), and substance P was increased in excitable compared to calm females both at weaning and breeding (p < .05). Low sire EPD docility score (p < .01), heifer-calf excitable temperament at weaning increased excitable temperament at breeding (p < .01). Controlling for BCS categories (p < .01), oestrous expression (p < .0001) and temperament at breeding by oestrous expression (p < .05), the calf's excitable temperament at weaning (p < .001) reduced P/AI (Calm, 62.7 (244/389) vs. Excitable, 53.4% (197/369); p < .01). In conclusion, selection of docile cows and sires with greater docility EPD score should be given consideration to reduce calf excitement. Temperament in beef female can be detected earlier in their life and could be used as a tool in the selection process and to improve their performances.


Asunto(s)
Conducta Animal/fisiología , Bovinos/fisiología , Temperamento/fisiología , Animales , Composición Corporal , Femenino , Hidrocortisona/sangre , Inseminación Artificial/veterinaria , Masculino , Embarazo , Índice de Embarazo , Sustancia P/sangre , Destete
2.
Reprod Domest Anim ; 52(1): 122-129, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27862440

RESUMEN

This study compared artificial insemination pregnancy rate (AI-PR) between 14-day CIDR-GnRH-PGF2α-GnRH and CIDR-PGF2α-GnRH synchronization protocol with two fixed AI times (56 or 72 hr after PGF2α). On day 0, heifers (n = 1311) from nine locations assigned body condition score (BCS: 1, emaciated; 9, obese), reproductive tract score (RTS: 1, immature, acyclic; 5, mature, cyclic) and temperament score (0, calm; and 1, excited) and fitted with a controlled internal drug release (CIDR, 1.38 g of progesterone) insert for 14 days. Within herd, heifers were randomly assigned either to no-GnRH group (n = 635) or to GnRH group (n = 676), and heifers in GnRH group received 100 µg of GnRH (gonadorelin hydrochloride, IM) on day 23. All heifers received 25 mg of PGF2α (dinoprost, IM) on day 30 and oestrous detection aids at the same time. Heifers were observed for oestrus thrice daily until AI. Within GnRH groups, heifers were randomly assigned to either AI-56 or AI-72 groups. Heifers in AI-56 group (n = 667) were inseminated at 56 hr (day 32 PM), and heifers in AI-72 group (n = 644) were inseminated at 72 hr (day 33 AM) after PGF2α administration. All heifers were given 100 µg of GnRH concurrently at the time AI. Controlling for BCS (p < .05), RTS (p < .05), oestrous expression (p < .001), temperament (p < .001) and GnRH treatment by time of insemination (p < .001), the AI-PR differed between GnRH treatment [GnRH (Yes - 60.9% (412/676) vs. No - 55.1% (350/635); p < .05)] and insemination time [AI-56 - 54.6% (364/667) vs. AI-72 - 61.8% (398/644); (p < .01)] groups. The GnRH treatment by AI time interaction influenced AI-PR (GnRH56 - 61.0% (208/341); GnRH72 - 60.9% (204/335); No-GnRH56 - 47.9% (156/326); No-GnRH72 - 62.8% (194/309); p < .001). In conclusion, 14-day CIDR synchronization protocol for FTAI required inclusion of GnRH on day 23 if inseminations were to be performed at 56 hr after PGF2α in order to achieve greater AI-PR.


Asunto(s)
Dinoprost/administración & dosificación , Sincronización del Estro/métodos , Estro/efectos de los fármacos , Fertilidad/efectos de los fármacos , Hormona Liberadora de Gonadotropina/administración & dosificación , Inseminación Artificial/veterinaria , Animales , Bovinos , Detección del Estro , Femenino , Embarazo , Índice de Embarazo
3.
Reprod Domest Anim ; 48(1): 171-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22712632

RESUMEN

The objective of the study was to elucidate mRNA expression of CYP26b1 (cytochrome P450, family 26, subfamily B, polypeptide 1) and signalling molecules ALDH1 (aldehyde dehydrogenase 1), CRABPII (cellular retinoic acid-binding protein II), RARα (retinoic acid receptor alpha) and STRA8 (stimulated by retinoic acid gene 8) in dog testis from different post-natal developmental ages. Testicular tissue samples were collected from medium-sized mixed breed dogs at different ages such as young (<4 months; N = 4), peripubertal (4-8 months; N = 3) and adult (>8 months; N = 4) were used to evaluate relative mRNA expression. Genes of RA-degrading enzyme CYP26b1, ALDH1 involved in RA synthesis and genes of carrier protein CRABPII involved in RA metabolism were turned on during the post-natal testicular development in dogs. Their expression pattern differs at different developmental ages (p < 0.05), and the levels of mRNA expression were compensated towards a normal developmental response for the sexual maturity and continuous spermatogenesis. The mRNA expression of RARα, one of the RA receptors participates in RA signalling in connection to spermatogenesis, was recorded in young and adult stages at varying degree. STRA8 is one of the responsive genes with regard to meiosis, and this functional gene product was expressed in all ages with the changing level (p < 0.01). In summary, the expression pattern of RA signalling molecules differed from young to adult ages, and it is expected that these changes are to compensate towards a normal developmental response for the sexual maturity and continuous spermatogenesis.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Perros/fisiología , Maduración Sexual/fisiología , Testículo/fisiología , Tretinoina/metabolismo , Animales , Sistema Enzimático del Citocromo P-450/genética , Masculino , Ácido Retinoico 4-Hidroxilasa , Transducción de Señal/fisiología
4.
Theriogenology ; 158: 39-49, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32927199

RESUMEN

Interferon-τ (IFNT), IFN stimulated genes (ISG15, CTSL1, RSAD2, SLC2A1, CXCL10, and SLC27A6), Peroxisome proliferator activated receptors (PPARA, D, and G), Retinoic acid receptors (RXRA, B, and G), and Mucin-1 (MUC1) play decisive roles in embryo elongation. The objective was to elucidate expressions of these genes in day 16 embryo [tubular (n = 4) vs. filamentous (n = 4)] and corresponding endometrium [without (n = 4) vs. with subclinical endometritis (SCE; n = 4)] of repeat breeder Holstein cows (2 × 2 factorial design). Results showed that the mRNA abundances (except PPARA and RXRB) were greater (P < 0.05) in filamentous embryo and endometrium without SCE compared with tubular embryo and endometrium with SCE, respectively. Overall, the mRNA abundances (except RSAD2, PPARA and RXRA) in filamentous embryo and corresponding endometrium of cows without SCE were greater (P < 0.05) than tubular embryo and corresponding endometrium of cows with SCE. Proteins IFNT, ISGs, PPARs and RXRs (except RXRB) were greater (P < 0.05) and protein MUC1 was lower (P < 0.01) in filamentous embryo and corresponding endometrium of cows without SCE compared to tubular embryo and corresponding endometrium of cows with SCE. On pairwise comparison, mRNA and protein abundances of MUC1 significantly differed between tubular embryo in uterus with or without SCE, and corresponding endometrium with or without SCE (P < 0.05). In conclusion, the mRNA and protein abundances of IFNT, ISG15, CXCL10, PPARG and MUC1 differed among filamentous and tubular conceptuses, and endometrium with or without SCE of repeat breeder cows on Day 16, indicating that these genes and their downstream signaling cascades play important roles in embryo elongation. Perhaps, interruptions in cross-talk between endometrium and conceptus impaired conceptus elongation in repeat breeder cows with SCE. In addition to disrupted signaling, the tubular conceptus (compared to filamentous conceptus) was unable to downregulate MUC1 (anti-adhesive glycocalyx) in repeat breeder cows with or without SCE, resulting in early embryonic demise.


Asunto(s)
Enfermedades de los Bovinos , Endometritis , Interferón Tipo I , Proteínas Gestacionales , Animales , Bovinos , Endometritis/veterinaria , Endometrio , Femenino , Mucina-1/genética
5.
Theriogenology ; 145: 39-47, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31986300

RESUMEN

Two experiments were conducted to determine effects of progesterone (P4) on cyclicity, estrus expression rate (EER) and artificial insemination pregnancy rate (AIPR) in beef heifers with various reproductive tract scores (RTS; 1 to 5; 1, immature, acyclic; 5, mature, cyclic). In Experiment 1, Angus-cross heifers (n = 100, 20 per RTS category; mean (±SEM) age, 15 ± 0.8 mo) were randomly assigned to receive a CIDR (Days -17 to -10) or no CIDR (untreated control), with weekly blood samples and ultrasonography (Days 0-85). Among heifers with RTS 2 to 4, median interval to cyclicity were shorter (P < 0.05) for heifers in CIDR versus control. In Experiment 2, Angus-cross heifers (n = 11,098) were assigned RTS, body condition score (BCS; 1 to 9; 1, emaciated; 9, obese) and temperament score (calm versus excitable). Heifers with RTS 2-5 (n = 10,569) were allocated to CO-Synch (n = 5099) or CO-Synch + CIDR (n = 5470). Estrus was detected until AI (72 h after PGF2α), with pregnancy diagnosis ∼70 d later. Controlling for RTS (P < 0.0001), BCS (P < 0.0001), temperament (P < 0.0001), age (P < 0.0001), treatment by RTS (P < 0.01), treatment by BCS (P < 0.01), and treatment by age, EER differed between CO-Synch and CO-Synch + CIDR (71.0 vs 75.9%, respectively, P < 0.0001). Accounting for RTS (P < 0.0001), BCS (P < 0.0001), temperament (P < 0.0001), age (P < 0.0001), heifers detected in estrus (P < 0.0001), RTS by treatment (P < 0.01), BCS by treatment (P < 0.01), and age by treatment, AIPR differed between CO-Synch versus CO-Synch + CIDR (55.3 vs 61.0%, P < 0.0001). In conclusion, exogenous P4 hastened cyclicity in pre- and peri-pubertal beef heifers. Further, it increased EER and AIPR. However, RTS, BCS and age influenced EER and AIPR. Among RTS 4 and 5, EER was greater for CO-Synch + CIDR vs CO-Synch. Among RTS 3 to 5, AIPR was greater for CO-Synch + CIDR versus CO-Synch. Progesterone status or supplementation at onset of synchronization protocols was critical to pregnancy outcomes, emphasizing heifer development for early puberty or progesterone supplementation.


Asunto(s)
Bovinos/fisiología , Estro/fisiología , Progesterona/farmacología , Administración Intravaginal , Animales , Dinoprost/farmacología , Sincronización del Estro/métodos , Femenino , Inseminación Artificial/veterinaria , Embarazo , Índice de Embarazo , Progesterona/administración & dosificación
6.
Theriogenology ; 126: 41-48, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30529997

RESUMEN

Sperm are highly specialized compartmentalized cells, with unique compositional, morphological and functional properties, including a plasma membrane that undergoes dynamic protein remodeling and surface modifications. Seminal plasma is a highly complex biological fluid containing proteins, amino acids, enzymes, fructose and other carbohydrates, lipids, major minerals and trace elements. Seminal plasma proteins are involved in regulation of osmotic pressure and pH of seminal plasma, transport of ions, lipid and hormones. The objective was to compare sperm and seminal plasma proteomes of bulls with differing fertility and to relate differences to biological processes. Semen was collected from bulls with high or low fertility (4 bulls in each category). Sperm and seminal plasma proteins were isolated, purified, subjected to 2-D gel electrophoresis, protein identification and ontology. In sperm and seminal plasma, binder of sperm proteins (BSP)-1, -3 and -5, and spermadhesin-1, ALB, TIMP, AKI and PEBP1 were higher for high-versus low-fertility bulls (P < 0.05), whereas proteins CLU, CCT5 and 8, ELSPbP1, and PSMA6 were more abundant in sperm and seminal plasma of low- versus high-fertility bulls (P < 0.05). Further, HSP90, ZFP34, IFNRF4, BCL62, NADHD, TUBB3 and Histone H1 were in greater abundance in sperm of high- compared with low-fertility bulls. The two key biological processes of proteins differentially expressed in high- and low-fertility bulls were metabolic processes and biological regulation. The most prominent molecular functions for proteins that differed are binding, catalytic and receptor activities. The main cellular components for proteins that differed are cellular, extracellular, and plasma membrane. Since protein content differed in high- versus low-fertility bulls, we inferred that the efficiency of associated sperm functions that are necessary for fertility may also differ between high- and low-fertility semen. In conclusion, differences between high- and low-fertility bulls regarding abundance of sperm and seminal plasma proteins likely contributed to differences in fertility.


Asunto(s)
Bovinos/fisiología , Fertilidad , Semen/metabolismo , Espermatozoides/metabolismo , Animales , Masculino , Proteoma , Proteómica , Análisis de Semen/veterinaria
7.
Theriogenology ; 107: 70-77, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29132037

RESUMEN

Objectives were to determine effects of: 1) handling temperament and administration of flunixin meglumine, an inhibitor of prostaglandin F2a (PGF2a) synthesis, given at the time of embryo transfer, on pregnancy rates in beef cattle embryo transfer recipients; 2) handling temperament and flunixin meglumine on peripheral concentrations of progesterone, cortisol, substance-P, prostaglandin F metabolites (PGFM, (13,14-dihydro-15-keto-PGF2a) and isoprostane 8-epi PGF2a; and 3) flunixin meglumine treatment on proportion of non-pregnant recipient cows returning to estrus within an expected interval. Angus cross beef cows (n = 710) at 7 locations were assigned a body condition score (BCS: 1, emaciated; 9, obese) and a temperament score [0, calm, slow chute exit; walk (n = 352), 1, excited, fast chute exit; jump, trot or run (n = 358)] and were synchronized with Select-Synch with a controlled internal drug release (CIDR) protocol. Estrus detection aids were applied at CIDR removal and cows were observed thrice daily for estrus until 72 h. Recipient cows that expressed estrus and had a corpus luteum received a frozen-thawed embryo on Day 7 after estrus. At the time of transfer, recipient cows were randomly allocated to receive 10 mL of flunixin meglumine im, immediately after transfer (n = 365) or served as an untreated control (n = 345). In a subset of cows (n = 80), ovarian ultrasonography was performed on the day of embryo transfer to determine corpus luteum volume and blood samples were collected twice, at the time of embryo transfer and 7 d later. All cows received estrus detection aids again on Day 14 (7 d after embryo transfer) and were observed for estrus twice daily until Day 24. Accounting for treatment (P > 0.1), embryo transfer difficulty score (P < 0.1), temperament by treatment interaction (P < 0.05), recipient cows with calm temperament had a higher pregnancy rate compared to those with an excited temperament [59.4 (209/352) vs 51.7% (185/358)]. The pregnancy rate for excitable cows without flunixin meglumine was lower (46.3% 81/175) compared to excitable cows that did received flunixin meglumine [56.8% (104/183)], and calm cows that did [59.3% (108/182)] or did not [59.4% (104/170)] receive flunixin meglumine. Proportions of non-pregnant recipient cows returning to estrus on Days 18-24 were not different between flunixin meglumine and control groups, 87.6% (134/153) and 84.0% (137/163), respectively (P > 0.1). At the time of embryo transfer and 7 d later, there were moderate to strong correlations among circulating concentrations of progesterone, cortisol, substance-P, PGFM and isoprostane 8-epi PGF2a. Among excitable cows, progesterone concentrations were lower and cortisol, substance-P, PGFM and isoprostane 8-epi PGF2a concentrations were greater for cows in the control group compared to cows that received flunixin meglumine. In conclusion, administration of flunixin meglumine improved pregnancy rates in excitable recipient cows following embryo transfer without affecting the proportion of non-pregnant cows returning to estrus.


Asunto(s)
Bovinos/fisiología , Clonixina/análogos & derivados , Transferencia de Embrión/veterinaria , Índice de Embarazo , Temperamento , Animales , Antiinflamatorios no Esteroideos/farmacología , Clonixina/farmacología , Femenino , Embarazo
8.
Theriogenology ; 89: 162-168, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28043347

RESUMEN

Mammalian sperm are exposed to a natural hypoosmotic environment during male-to-female reproductive tract transition; although this activates sperm motility in vivo, excessive swelling can harm sperm structure and function. Aquaporins (AQPs) is a family of membrane-channel proteins implicated in sperm osmoregulation. The objective was to determine associations among relative sperm volume shift, hypoosmotic swelling test (HOST), sperm aquaporin (AQP) 7 mRNA abundances, and sire conception rate (SCR; fertility estimate) in Holstein bulls at a commercial artificial insemination center. Three or four sires for each full point SCR score from -4 to +4 were included. Each SCR estimate for study bulls (N = 30) was based on > 500 services (mean ± SEM) of 725 ± 13 services/sire). Sperm from a single collection day (two ejaculates) from these commercial Holstein bulls were used. Relative mRNA expression of AQP7 in sperm was determined by polymerase chain reaction. Mean relative sperm volume shift and percentage of sperm reacted in a HOST (% HOST) were determined (400 sperm per bull) after incubating in isoosmotic (300 mOsm/kg) and hypoosmotic (100 mOsm/kg) solutions for 30 min. There was no correlation between %HOST and SCR (r = 0.28 P > 0.1). However, there was a positive correlation between relative sperm volume shift and SCR (r = 0.65, P < 0.05). Furthermore, AQP7 mRNA abundance was positively correlated to both relative volume shift (r = 0.73; P < 0.05) and to SCR (r = 0.67; P < 0.05). The mRNA expressions of AQP7 and relative sperm volume shift differed (P < 0.05) among low- (<2 SCR), average- (-2 to +2) and high- (>2) fertility sire groups. In conclusion, bulls with higher SCR had significantly greater AQP7 mRNA abundance in frozen-thawed sperm. This plausibly contributed to greater regulation of sperm volume shift, which apparently conferred protection from detrimental swelling and impaired functions.


Asunto(s)
Acuaporinas/metabolismo , Fertilidad , Análisis de Semen/veterinaria , Espermatozoides/metabolismo , Animales , Acuaporinas/genética , Bovinos , Inseminación Artificial/veterinaria , Masculino , Presión Osmótica , ARN Mensajero/metabolismo
9.
Theriogenology ; 102: 154-161, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28763634

RESUMEN

The objectives of the current experiment were to determine if delaying insemination by 8 h in a FTAI protocol would alter estrus expression and pregnancy rates in cows inseminated with sex-sorted semen, characterize bull variation in pregnancy rates to sex-sorted semen and examine the impact of repeated years of FTAI to sex-sorted semen on calving distribution. Over three breeding seasons, postpartum cows (n = 839) were estrous synchronized using the 5-day CO-Synch + CIDR system. Cows were given GnRH (100 µg i.m., Factrel) at time of insertion of a controlled internal drug releasing device (CIDR; Eazi-Breed CIDR). Five d later CIDR was removed and PGF2α (25 mg i.m., Lutalyse) was given at removal and 8 h later. Estrus detection aids were applied at CIDR removal. Cows were inseminated with X-sorted or Y-sorted sex-sorted semen at 72 h (NORM) or 80 h (DELAY) after CIDR removal, and GnRH was administered at AI. At insemination, estrus status was categorized as positive (YES), partial (QUES), unknown (NR) or negative (NO). Bulls were introduced to cows at 14 d and removed at 60 d after FTAI. Pregnancy diagnosis was performed by ultrasound at d 60 after FTAI and via palpation at 60 d after bull removal. There was no difference (P > 0.05) in pregnancy rates to sex-sorted semen or final pregnancy rates between NORM and DELAY cows. Pregnancy to sex-sorted semen averaged 35.2% whereas final pregnancy rates were 90.6%. More cows (P < 0.05) in the DELAY group expressed estrus before FTAI, but this increase did not alter pregnancy rates to sex-sorted semen. Expression of estrus before FTAI increased (P < 0.02) pregnancy rates to sex-sorted semen across treatments with differences being YES > QUES or NR > NO. There was considerable variation in pregnancy rate by bull (P < 0.05) with pregnancy rates ranging from 55.6% to 19.3%. Whole herd calving distribution was altered (P < 0.05) after 3 y of use of sex-sorted semen compared to the previous 3 y when conventional semen was used. We conclude that delaying insemination by 8 h in an FTAI protocol did not improve pregnancy rates to sex-sorted semen despite more cows exhibiting estrus before FTAI. In addition, a high bull to bull variation in pregnancy rates to sex-sorted semen is a limitation in FTAI systems. Further research into FTAI strategies for use with sex-sorted semen is warranted.


Asunto(s)
Bovinos/fisiología , Inseminación Artificial/veterinaria , Índice de Embarazo , Preselección del Sexo/veterinaria , Animales , Sincronización del Estro/métodos , Femenino , Masculino , Embarazo , Semen , Espermatozoides , Factores de Tiempo
10.
J Anim Sci ; 95(11): 5105-5111, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29293737

RESUMEN

Our objective was to determine which of 2 split-time AI programs applied to suckled beef cows would result in greater pregnancy risk. Suckled beef cows (n = 1,062) at 12 locations in 4 states (CO, KS, MY, and WA) were enrolled. Cows were treated on d -7 with a progesterone insert concurrent with 100 µg GnRH and on d 0 with 25 mg PGF plus removal of the insert. Estrus-detection patches were affixed to cows at insert removal. The study was designed as a completely randomized experiment of 2 treatment combinations. Within location and balanced for parity (primiparous vs. multiparous), cows were assigned randomly to 2 treatment times (55 vs. 65 h after CIDR insert removal) at which time estrus-detection patches were assessed. Estrus was defined to have occurred when an estrus-detection patch was > 50% colored (activated). Cows determined to be in estrus were inseminated at either 55 or 65 h, whereas the residual nonestrous cows in both treatment times received GnRH at 55 or 65 h but were inseminated 20 h later at 75 or 85 h, respectively. Pregnancy outcomes were determined at 36 d after AI and at the end of the breeding season. Thus, pregnancy outcomes of interest were compared between the 55 + 75-h treatment combination and that of the 65+85-h combination. Expression of estrus was greater ( = 0.001) by 65 h after PGF than by 55 h (62.0% vs. 41.9%), respectively, and this proportion was influenced by parity (time x parity interaction; = 0.006). As a result, proportionally more ( < 0.001) cows received the timed AI at 75 than 85 h (59.4% vs. 40.6%). Similar proportions of cows not in estrus by 55 or 65 h were detected in estrus by 75 or 85 h (40.1% vs. 39.3%), respectively. The cumulative proportion of cows in estrus by 75 h was less ( < 0.001) than that by 85 h (66.7% vs. 76.7%), respectively. Pregnancy risks at 36 d differed among treatments, with cows detected in estrus and inseminated at 55 or 65 h having greater pregnancy risks than their time-inseminated herd mates at 75 or 85 h (62.3% vs.49.7%), respectively. Overall pregnancy risk for cows in the 65+85-h treatment combination was greater at 36 d than for cows in the 55 + 75-h treatment combination (61.0% vs. 51.4%), respectively. We conclude that the 65 + 85-h treatment combination produced more pregnancies than the 55 + 75-h combination, but its implementation may be somewhat less convenient in terms of cow handling times.


Asunto(s)
Bovinos/fisiología , Hormona Liberadora de Gonadotropina/administración & dosificación , Inseminación Artificial/veterinaria , Resultado del Embarazo/veterinaria , Progesterona/administración & dosificación , Animales , Estro , Detección del Estro , Femenino , Paridad , Embarazo , Riesgo , Factores de Tiempo
11.
Theriogenology ; 100: 72-79, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28708536

RESUMEN

The objectives of this study were 1. to determine the associations among circulating anti-Mullerian hormone (AMH), insulin like growth factor 1 (IGF1) and cadmium (Cd) concentrations of lactating Holstein cows at the time of superovulation and 2. to determine the effect of circulating AMH, IGF1 and Cd concentrations on the superovulatory response in Holstein dairy cows. Holstein cows (n = 30) were milked thrice daily and housed and fed in free stall barn as a separate group. All animals were synchronized for superovulation and flushed. Three blood samples for AMH, IGF1 and Cd analysis were collected prior to superovulation, at estrus and at the time of embryo collection. The concentrations of blood makers prior to superovulation were highly correlated to superovulatory response. Circulating concentrations of AMH, IGF1 prior to superovulation were negatively correlated to Cd concentrations (P < 0.05). There was no correlation between circulating concentrations of AMH and IGF1. The number of corpus luteum (r = 0.71), total embryo (r = 0.67), total transferable embryo (r = 0.51) and total grade 1 embryo (r = 0.5) were positively correlated to AMH concentrations (P < 0.05). There was a trend for negative correlation found between circulating cadmium concentrations and total grade 1 embryo yield (P < 0.1). When cows were classified into quartiles (Q) of circulating AMH concentration, number of corpus luteum, and total embryos, total transferable embryos and total grade 1 embryos yield was significantly different for AMH quartiles. The superovulatory response parameters evaluated were increased with increased AMH concentrations; particularly we observed a >2-fold difference between first and fourth AMH quartiles in total transferable embryo yield and total grade 1 embryo yield. In conclusion, circulating AMH concentration was strongly associated with superovulatory response. Measuring AMH before enrolling cows in superovulation programs will likely allow practitioners to improve numbers of embryos produced and, thereby, reduce costs per embryo produced.


Asunto(s)
Hormona Antimülleriana/sangre , Cadmio/sangre , Bovinos/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Superovulación/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Cloprostenol/administración & dosificación , Cloprostenol/farmacología , Transferencia de Embrión , Femenino , Hormona Folículo Estimulante/administración & dosificación , Hormona Folículo Estimulante/farmacología , Factor I del Crecimiento Similar a la Insulina/genética , Recolección de Tejidos y Órganos
12.
Theriogenology ; 85(2): 173-9, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26534827

RESUMEN

Reckless use of antibiotics and/or development of biofilm are the rationale for the development of multidrug resistance (MDR) of pathogenic bacteria. The objective of the present study was to detect MDR genes in Trueperella pyogenes and to detect biofilm virulence factor (VF) genes in Escherichia coli isolated from the uterus of postpartum dairy cows. Uterine secretions from different parity postpartum Holstein cows (n = 40) were collected using cytobrush technique after a sterile procedure from cows with varying degree of uterine inflammatory conditions. The cytobrush was stored in a specimen collector, placed in a cooler with ice, and transported to the laboratory within 2 hours. The pathogens were isolated and were identified initially by their colony morphology and biochemical characteristics. To further identify and classify the single species, and to determine the presence of MDR and VF genes, the genes fragments were amplified using the respective primers by either singleplex or multiplex polymerase chain reaction protocol, and amplicons were detected by electrophoresis method. T pyogenes was isolated in 17 of 40 (42.5%) cows in the study population as recognized by the 16S rRNA gene. Of the positive T pyogenes samples, 8 of 17 (42.1%) were positive for integron type 1 (intI I), and none were positive for integron type 2 (intI II). Of those 8 positive for intI I, six of eight (66.7%) were positive for amplicons aadA5 and aadA24-ORF1 at 1048 and 1608 bp, respectively, associated with specific drug resistance. Presence of addA5 indicated resistance to sulfadiazine, bacitracin, florfenicol, and ceftiofur. Presence of addA24-ORF1 indicated resistant to sulfadiazine, bacitracin, penicillin, clindamycin, and erythromycin. E coli was isolated in 18 of 40 (45.0%) cows in the study population. The genes for VF, Agn43a, and Agn43 b, associated with biofilm production, were found in 6 of 18 (33.3%) of the positive isolates. Both T pyogenes MDR gene and E coli biofilm VF existed in more severe form of uterine diseases than subclinical endometritis. In conclusion, 35% of T pyogenes isolates found were positive for a gene cassette associated with antibiotic resistance, and 33% of the E coli isolates contained genes for the VF associated with biofilm production.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Bovinos/microbiología , Resistencia a Múltiples Medicamentos/genética , Periodo Posparto , Útero/microbiología , Factores de Virulencia/genética , Actinomycetaceae/genética , Actinomycetaceae/aislamiento & purificación , Infecciones por Actinomycetales/veterinaria , Animales , Enfermedades de los Bovinos/microbiología , Farmacorresistencia Bacteriana/genética , Endometritis/microbiología , Endometritis/veterinaria , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/veterinaria , Femenino , ARN Ribosómico 16S/análisis , Enfermedades Uterinas/microbiología , Enfermedades Uterinas/veterinaria
13.
Theriogenology ; 81(6): 797-804, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24485555

RESUMEN

The objectives were (1) to determine the effects of gonadorelin hydrochloride (GnRH) injection at controlled internal drug release (CIDR) insertion on Day 0 and the number of PGF2α doses at CIDR removal on Day 5 in a 5-day CO-Synch + CIDR program on pregnancy rate (PR) to artificial insemination (AI) in heifers; (2) to examine how the effect of systemic concentration of progesterone and size of follicles influenced treatment outcome. Angus cross beef heifers (n = 1018) at eight locations and Holstein dairy heifers (n = 1137) at 15 locations were included in this study. On Day 0, heifers were body condition scored (BCS), and received a CIDR. Within farms, heifers were randomly divided into two groups: at the time of CIDR insertion, the GnRH group received 100 µg of GnRH and No-GnRH group received none. On Day 5, all heifers received 25 mg of PGF2α at the time of CIDR insert removal. The GnRH and No-GnRH groups were further divided into 1PGF and 2PGF groups. The heifers in 2PGF group received a second dose of PGF2α 6 hours after the administration of the first dose. Beef heifers underwent AI at 56 hours and dairy heifers at 72 hours after CIDR removal and received 100 µg of GnRH at the time of AI. Pregnancy was determined approximately at 35 and/or 70 days after AI. Controlling for herd effect (P < 0.06), the treatments had significant effect on AI pregnancy in beef heifers (P = 0.03). The AI-PRs were 50.3%, 50.2%, 59.7%, and 58.3% for No-GnRH + PGF + GnRH, No-GnRH + 2PGF + GnRH, GnRH + PGF + GnRH, and GnRH + 2PGF + GnRH groups, respectively. The AI-PRs were ranged from 50% to 62.4% between herds. Controlling for herd effects (P < 0.01) and for BCS (P < 0.05), the AI pregnancy was not different among the treatment groups in dairy heifers (P > 0.05). The AI-PRs were 51.2%, 51.9%, 53.9%, and 54.5% for No-GnRH + PGF + GnRH, No-GnRH + 2PGF + GnRH, GnRH + PGF + GnRH, and GnRH + 2PGF + GnRH groups, respectively. The AI-PR varied among locations from 48.3% to 75.0%. The AI-PR was 43.5%, 50.4%, and 64.2% for 2.5 or less, 2.75 to 3.5, and greater than 3.5 BCS categories. Numerically higher AI-PRs were observed in beef and dairy heifers that exhibited high progesterone concentrations at the time of CIDR insertion (>1 ng/mL, with a CL). In addition, numerically higher AI-PRs were also observed in heifers receiving CIDR + GnRH with both high and low progesterone concentration (<1 ng/mL) initially compared with heifers receiving a CIDR only with low progesterone. In dairy heifers, there were no differences in the pregnancy loss between 35 and 70 days post-AI among the treatment groups (P > 0.1). In conclusion, GnRH administration at the time of CIDR insertion is advantageous in beef heifers, but not in dairy heifers, to improve AI-PR in the 5-day CIDR + CO-Synch protocol. In addition, in this study, both dairy heifers that received either one or two PGF2α doses at CIDR removal resulted in similar AI-PR in this study regardless of whether they received GnRH at CIDR insertion.


Asunto(s)
Dinoprost/farmacología , Sincronización del Estro/métodos , Hormona Liberadora de Gonadotropina/farmacología , Animales , Bovinos , Femenino , Inseminación Artificial/veterinaria , Embarazo
14.
Cent Asian J Glob Health ; 2(2): 76, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-29755885

RESUMEN

Most emerging infectious diseases are zoonoses, which could severely hamper reaching the targets of millennium development goals (MDG). Five out of the total eight MDG's are strongly associated with the Emerging Infectious Diseases (EIDs). Recent emergence and dissemination of drug-resistant pathogens has accelerated and prevent reaching the targets of MDG, with shrinking of therapeutic arsenal, mostly due to antimicrobial resistance (AMR). World Health Organization (WHO has identified AMR as 1 of the 3 greatest threats to global health. Until now, methicillin-resistant staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) have been observed in hospital-acquired infections. In India, within a span of three years, New Delhi metallo-ß-lactamase prevalence has risen from three percent in hospitals to twenty- fifty percent and is found to be colistin resistant as well. Routine use of antimicrobials in animal husbandry accounts for more than 50% in tonnage of all antimicrobial production to promote growth and prophylaxis. This has consequences to human health and environmental contamination with a profound impact on the environmental microbiome, resulting in resistance. Antibiotic development is now considered a global health crisis. The average time required to receive regulatory approval is 7.2 years. Moreover, the clinical approval success is only 16%. To overcome resistance in antimicrobials, intersectoral partnerships among medical, veterinary, and environmental disciplines, with specific epidemiological, diagnostic, and therapeutic approaches are needed. Joint efforts under "One Health", beyond individual professional boundaries are required to stop antimicrobial resistance against zoonoses (EID) and reach the MDG.

15.
Theriogenology ; 76(3): 482-91, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21550107

RESUMEN

The objectives were to determine the effects of tocopherol on serum concentrations of 8-epi-prostaglandin F2 alpha (isoprostane) and adiponectin, and to determine mRNA expression of peroxisome proliferator-activated receptor gamma (PPARγ), adiponectin (ADIPQ), and related genes in the uterus and placentome of tocopherol-supplemented ewes during late pregnancy. Pregnant ewes were individually given daily oral supplements of 500 mg of alpha-tocopherol (aT; N=6), 1000 mg of gamma-tocopherol (gT; N=7), or placebo (CON; N=5) from 107 to 137 d post breeding. Serum and tissue samples were collected weekly and at the end of the study, respectively. At the end of the study, in the aT, gT and CON groups, serum concentrations were 251.7 ± 12.3, 232.5 ± 6.8, and 285.8 ± 9.4 ηg/µL, respectively, for isoprostane, and were 341.7 ± 9.3, 358.7 ± 11.5, and 305.2 ± 2.8 ηg/µL for adiponectin (significantly different for aT and gT versus CON). The mRNA abundance for PPARγ in the cotyledon and caruncle were similar in aT and gT ewes. The PPARγ, ADIPQ and LEP mRNA expressions were reduced (P < 0.05) in the cotyledon and caruncle in aT versus CON ewes. However, associations of PPARγ mRNA expression with ADIPQ and LEP mRNA expressions were negatively related in cotyledons, positively related in the caruncle, and positively downregulated in the uterus in gT supplemented ewes accounting for CON. The IGF-1 mRNA expression was downregulated in the cotyledon, caruncle and uterus in aT supplemented ewes. Expression of IGF-2 mRNA was upregulated in the cotyledon and caruncle, and downregulated in the uterus in gT supplemented ewes. In conclusion, oral supplementation of tocopherol during late gestation in ewes decreased isoprostane concentrations and increased adiponectin concentrations in the serum, and significantly affected PPARγ- and ADIPQ-related genes in the utero-placental network. Perhaps the pro-angiogenic tocopherol effect in the placental vascular network was via PPARγ-mediated regulation of genes responsible for metabolism of glucose and fatty acid, as well as for angiogenesis.


Asunto(s)
Placenta/efectos de los fármacos , Ovinos/genética , Tocoferoles/farmacología , Útero/efectos de los fármacos , Adiponectina/sangre , Animales , Dinoprost/análogos & derivados , Dinoprost/sangre , Femenino , Regulación del Desarrollo de la Expresión Génica , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/metabolismo , PPAR gamma/genética , PPAR gamma/metabolismo , Placenta/metabolismo , Embarazo , ARN Mensajero/metabolismo , Ovinos/metabolismo , Útero/metabolismo
16.
Theriogenology ; 76(3): 570-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21529916

RESUMEN

The objective was to determine the association of mRNA expression of cystine rich secretary protein 2 (CRISP2), chaperonin containing T-complex protein 1, subunit 8 (CCT8), and phosphatidylethanolamine-binding protein 1 (PEBP1), in sperm of Holstein bulls with Sire Conception Rate (SCR) scores between -4 and +4. These proteins were involved in sperm capacitation and sperm-egg fusion. Samples of sperm obtained on a single day from Holstein bulls (N = 34) in a commercial AI centre were used to evaluate relative mRNA expression of CRISP2, CCT8, and PEBP1. The mRNA abundance of CRISP2 was positively correlated (r = 0.88; P < 0.002), CCT8 was negatively correlated (r = -0.87; P < 0.002), and PEBP1 was positively correlated (r = 0.83; P < 0.006) with SCR-scores. The means of CRISP2 mRNA abundance was greater among positive SCR-score bulls (2.5 to 8 fold), the means of CCT8 mRNA abundance was greater among the negative SCR-score bulls (9.5 to 3.5 fold), and the means of PEBP1 mRNA abundance was greater for the positive SCR-score bulls (5.4 to 7.7 fold). In multivariate regression models predicting SCR-scores, mRNA abundance of CCT8 was significantly associated with SCR-score in all models. In the presence of CRISP2 mRNA abundance in the model, the SCR score's predictability of PEBP1 was insignificant. However, in the absence of CRISP2 mRNA abundance in the model, the SCR-score's predictability of PEBP1 was significant. In multivariate regression models, CRISP2 and CCT8 mRNA expression in sperm accounted for 95% of the variance in Holstein bull's SCR-scores. In conclusion, Holstein bulls with greater CRISP2 and lower CCT8 mRNA expression in sperm had higher probabilities of siring calves.


Asunto(s)
Bovinos/genética , Chaperonina con TCP-1/genética , Fertilización/genética , Glicoproteínas/genética , Proteínas de Unión a Fosfatidiletanolamina/genética , ARN Mensajero/metabolismo , Espermatozoides/fisiología , Animales , Bovinos/metabolismo , Chaperonina con TCP-1/metabolismo , Chaperonina con TCP-1/fisiología , Femenino , Fertilidad/genética , Glicoproteínas/metabolismo , Glicoproteínas/fisiología , Masculino , Análisis Multivariante , Proteínas de Unión a Fosfatidiletanolamina/metabolismo , Proteínas de Unión a Fosfatidiletanolamina/fisiología , Análisis de Regresión , Interacciones Espermatozoide-Óvulo/genética
17.
Theriogenology ; 74(6): 1002-9, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20580078

RESUMEN

The objective was to compare the timed AI pregnancy rate of Angus-cross beef cows synchronized with a 5-d CO-Synch + CIDR (a progesterone-releasing intravaginal insert) protocol and given two doses of PGF(2 alpha) (PGF), with the first dose in conjunction with CIDR withdrawal on Day 5, and the second dose given either early or late relative to the first dose. All cows (N = 1782) at 16 locations received 100 microg of GnRH + CIDR on Day 0. Cows received 25 mg of PGF concurrent with removal of the CIDR on Day 5, and were randomly allocated within locations to receive a second PGF either early (N = 881; from 0.5 to 3.9 h) or late (N = 901; from 4.5 to 8.15 h) relative to the first PGF treatment. On Day 8 (72 h after CIDR removal), all cows were inseminated and concurrently given 100 microg of GnRH. Cows were fitted with a pressure-sensitive mount detection device (Kamar) at CIDR removal. Cows were observed twice daily through Day 7 and at the time of AI on Day 8 for estrus and Kamar status (estrus - red, partial and lost Kamar versus no estrus - white Kamar) was recorded. Accounting for location, season, AI sire, cow observed in estrus or not at or before timed AI, and treatment by cows observed in estrus interaction, timed AI pregnancy rates were greater for the late (6.45 +/- 0.03 h) than the early (2.25 +/- 0.05 h) interval, 57.2 vs. 52.7%, respectively (P < 0.05). In conclusion, cows that received the second PGF late after the first PGF on the day of CIDR removal in a 5 d CO-Synch + CIDR synchronization protocol had significantly higher timed AI pregnancy rates than those receiving the second PGF early after the first PGF.


Asunto(s)
Bovinos , Dinoprost/administración & dosificación , Sincronización del Estro/métodos , Inseminación Artificial , Índice de Embarazo , Progesterona/administración & dosificación , Algoritmos , Animales , Bovinos/fisiología , Esquema de Medicación , Femenino , Inseminación Artificial/métodos , Inseminación Artificial/veterinaria , Masculino , Embarazo , Factores de Tiempo
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