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1.
J Appl Microbiol ; 129(5): 1173-1184, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32416023

RESUMO

AIMS: Campylobacter sp. are important causes of reproductive disease in ruminants worldwide. Although healthy bulls are well-known carriers for infection of cows, the role of rams as a potential source for infecting ewes is unclear. This study aimed to determine prevalence, species distribution, genetic diversity and antimicrobial susceptibility profiles of Campylobacter sp. isolated from the preputial cavity of healthy rams. METHODS AND RESULTS: The material of this prospective study comprised 191 swab samples taken from the preputial cavity of healthy rams. Enrichment and membrane filtration were employed for the isolation of Campylobacter. Presumptive isolates were confirmed as Campylobacter by phenotypic and molecular tests. 16S rRNA gene sequence analysis was used for the definitive identification of the isolates at species level, and genotyping was performed using pulsed-field gel electrophoresis (PFGE). The susceptibility of the Campylobacter sp. isolates to various antibiotics was determined by the disk diffusion test. In all, 27 of the 191 (14·13%) swab samples were found to be positive for Campylobacter sp. (28 isolates were recovered in total). Per phenotypic and genotypic analyses, one isolate was identified as Campylobacter mucosalis and the remaining 27 isolates were identified as Campylobacter sputorum bv. faecalis. The PFGE analysis of the C. sputorum biovar faecalis isolates produced 17 clusters and 24 different pulsotypes, indicating high genetic heterogeneity. All 28 isolates were found to be susceptible to all of the antibiotics tested. CONCLUSIONS: Healthy rams may be an important reservoir of different Campylobacter species in the preputium. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated for the first time that healthy rams can carry different Campylobacter sp. including genetically diverse C. sputorum bv. faecalis and C. mucosalis in the preputial cavity. Further investigation on the potential implication of this finding on sheep reproductive health (e.g. infectious infertility, and abortion) and overall epidemiology of Campylobacter may be warranted.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/veterinária , Campylobacter/efeitos dos fármacos , Campylobacter/genética , Doenças dos Ovinos/microbiologia , Animais , Campylobacter/classificação , Campylobacter/isolamento & purificação , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Portador Sadio/microbiologia , Portador Sadio/veterinária , Prepúcio do Pênis/microbiologia , Variação Genética , Masculino , Estudos Prospectivos , RNA Ribossômico 16S/genética , Ovinos , Doenças dos Ovinos/epidemiologia , Carneiro Doméstico , Turquia/epidemiologia
2.
J Dairy Sci ; 97(9): 5401-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24952780

RESUMO

Our objectives were to evaluate the efficacy of ampicillin trihydrate for the treatment of metritis in dairy cows compared with ceftiofur hydrochloride and the subsequent effects on pregnancy at first insemination (P/AI). Cows in the first 12 d in milk (DIM) with a uterine discharge score of 5 (watery, reddish or brownish discharge of foul smell) and rectal temperature <39.5°C were diagnosed with metritis based on the fetid discharge, and cows with metritis and rectal temperature ≥39.5°C were diagnosed as having puerperal metritis. Cows with metritis (n=528) were blocked by parity and type of metritis as fetid discharge or puerperal metritis and, within each block, assigned randomly to receive 11mg/kg of ampicillin (n=259) or 2.2mg/kg of ceftiofur (n=269) once daily for 5 d. Day of diagnosis of metritis was considered study d 1. A cohort of 268 cows without metritis was selected randomly at 12 DIM. Rectal temperature was measured in cows with metritis on study d 1 to 7, and 12, and vaginal discharge was scored on study d 5, 7, and 12. Metritis cure was characterized by vaginal discharge score of <5 or by vaginal discharge score of <5 and no fever. At 32±3 DIM, vaginal discharge was scored for diagnosis of purulent vaginal discharge. At 39±3 DIM, endometrial cytology was performed. At 53±3 and 67±3 DIM, ovaries were scanned to determine estrous cyclicity. Pregnancy was evaluated after the first AI. Cure of metritis based on vaginal discharge <5 was greater for ampicillin than ceftiofur on d 5 (37.1 vs. 25.2%) and 7 (57.2 vs. 46.3%), but not on d 12 (82.0 vs. 85.0%). Cure of metritis based on vaginal discharge <5 and no fever was greater for ampicillin than for ceftiofur only on d 7 (50.4 vs. 37.9%), but not on d 5 (23.1 vs. 17.6%) and 12 (66.1 vs. 67.4%). Cows with puerperal metritis had reduced cure compared with cows with fetid discharge on d 5 (30.5 vs. 12.8%), 7 (55.2 vs. 33.6%), and 12 (72.0 vs. 61.1%). The proportion of cows with fever on any day after therapy started did not differ between treatments. Fifty-three percent of cows with metritis based on fetid discharge developed fever after initiating antimicrobial therapy. Cows receiving ampicillin had less prevalence of purulent vaginal discharge than those treated with ceftiofur (57.7 vs. 67.8%), but they were both greater than cows without metritis (21.9%). Prevalence of cytological endometritis did not differ between ampicillin and ceftiofur (30.0 vs. 25.4%), but they were both greater than cows without metritis (14.5%). The proportion of estrous cyclic cows (75.0%) and P/AI did not differ among treatments (ampicillin=28.0% vs. ceftiofur=28.3% vs. without metritis=30.5%). Clinical cure was faster for ampicillin than for ceftiofur, but on study d 12 both treatments resulted in similar cure. Clinical cure was less for cows with puerperal metritis than for cows with fetid uterine discharge. Despite differences in uterine health, P/AI at the first insemination did not differ among treatments.


Assuntos
Ampicilina/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Cefalosporinas/uso terapêutico , Endometrite/tratamento farmacológico , Endometrite/veterinária , Fertilidade/efeitos dos fármacos , Animais , Antibacterianos/uso terapêutico , Temperatura Corporal , Bovinos/fisiologia , Doenças dos Bovinos/diagnóstico , Dieta/veterinária , Endometrite/diagnóstico , Feminino , Febre/tratamento farmacológico , Abrigo para Animais , Período Pós-Parto , Gravidez , Prevalência , Descarga Vaginal/tratamento farmacológico , Descarga Vaginal/veterinária
3.
Reprod Domest Anim ; 49(2): 333-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24467764

RESUMO

The aim of this study was to compare pregnancy per artificial insemination (P/AI) after timed AI with sex-sorted sperm (SS) or conventional semen (CS) in lactating dairy cows. Cyclic cows (n = 302) were synchronized by Ovsynch and randomly assigned into two groups at the time of AI. Cows with a follicle size between 12 and 18 mm and clear vaginal discharge at the time of AI were inseminated with either frozen-thawed SS (n = 148) or CS (n = 154) of the same bull. A shallow uterine insemination was performed into the uterine horn ipsilateral to the side of probable impending ovulation. Pregnancy per AI on Day 31 tended (p = 0.09) to be less for SS (31.8%) than CS (40.9%). Similarly, P/AI on Day 62 was less (p = 0.01) for cows inseminated with SS (25.7%) compared with CS (39.0%). The increased difference in fertility between treatments from Days 31 to 62 was caused by the greater (p = 0.02) pregnancy loss for cows receiving SS (19.2%) than CS (4.8%). Cow parity (p = 0.02) and season (p < 0.01) when AI was performed were additional factors affecting fertility. Primiparous cows had greater P/AI than multiparous cows both on Day 31 (41.7% vs 25.0% in SS and 53.0% vs 31.8% in CS groups) and on Day 62 (33.3% vs 20.5% in SS and 48.5% vs 31.8% in CS groups). During the hot season of the year, P/AI on Day 31 was reduced (p = 0.01) in the SS group (19.6%) when compared with the rates during the cool season (38.1%). In conclusion, sex-sorted sperm produced lower fertility results compared to conventional semen even after using some selection criteria to select most fertile cows.


Assuntos
Bovinos/fisiologia , Inseminação Artificial/veterinária , Pré-Seleção do Sexo/veterinária , Animais , Feminino , Gravidez , Taxa de Gravidez
4.
Artigo em Inglês | MEDLINE | ID: mdl-24326794

RESUMO

The detection of bovine viral diarrhea virus (BVDV) in a female Holstein calf presented with perosomus elumbis, a congenital anomaly, is reported here. A cow with dystocia was evaluated and an abnormal dead calf was detected during vaginal examination. The calf was retrieved via caesarean section and exhibited abnormalities characteristic of PE, such as vertebral and pelvic malformations. These abnormalities were further confirmed using radiographic and necropsy examinations. At necropsy cerebellar hypoplasia was an additional finding, which is a typical lesion associated with bovine virus diarrhea (BVD). Several tissue samples from the calf were tested for the presence of antigens of BVDV and bovine herpesvirus-1 (BHV-1) by ELISA. In addition, sera samples from the dam and calf were tested for the presence of antibodies against BVDV, BHV-1, and bluetongue disease virus (BTV) using a virus neutralization assay. Results indicated that the calf was congenitally infected with BVDV, whereas there was no evidence for the presence of BHV-1 and BTV. In the dam's serum no antibodies against BVDV, BHV-1, and BTV were detected. Even though the etiology of perosomus elumbis is unknown, BVDV, which causes fetal anomalies at early gestation in cows, may have been a contributing factor in this case.


Assuntos
Anormalidades Múltiplas/veterinária , Vírus da Diarreia Viral Bovina/isolamento & purificação , Doenças Musculoesqueléticas/veterinária , Anormalidades Múltiplas/virologia , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina , Bovinos , Feminino , Plexo Lombossacral/anormalidades , Doenças Musculoesqueléticas/congênito , Doenças Musculoesqueléticas/virologia , Gravidez , Medula Espinal/anormalidades , Coluna Vertebral/anormalidades , Natimorto/veterinária
5.
Acta Chir Belg ; 113(4): 281-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24224438

RESUMO

INTRODUCTION: Articles published in the English language report that 15-20% of the inguinal hernias in female children are sliding hernias. These studies do not specify the age at moment of surgery, neither the age distribution of sliding hernia. We retrospectively evaluated inguinal canal pathologies to answer these questions. MATERIAL AND METHOD: We retrospectively evaluated the records of the patients operated on at the Pediatric Surgery Clinics of the Ordu, Usak and Denizli State Hospitals and the Afyon Obstetrics and Gynecology Hospital. RESULTS: A total of 3105 cases had been operated on for an inguinal hernia between January 2008 and December 2010 and 673 (21.6%) were female. The most common age at surgery was between 0 and 1 years (26.5%). A sliding hernia was found in 22.4% (n = 151) of all cases. The sliding hernia rate was 45.8 (n = 82) and 14.9% (n = 69) in children younger and older than 1 year of age respectively (p < 0.05). The most frequently sliding organ in both groups was the ovary, followed by the fallopian tubes. CONCLUSION: A sliding hernia is more common in female children under the age of 1 year and surgical treatment should be planned within a short period once the diagnosis is made. In addition, this recent statistical value for subjects aged 0 to 1 year and over 1 year can be used in new clinical studies.


Assuntos
Hérnia Inguinal/epidemiologia , Herniorrafia/métodos , Canal Inguinal/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Hérnia Inguinal/patologia , Hérnia Inguinal/cirurgia , Humanos , Incidência , Canal Inguinal/cirurgia , Masculino , Prevalência , Estudos Retrospectivos , Fatores Sexuais , Resultado do Tratamento , Turquia/epidemiologia
6.
Clin Oncol (R Coll Radiol) ; 25(11): 647-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23948462

RESUMO

AIMS: The role of induction chemotherapy (ICT) for head and neck squamous cell carcinoma (HNSCC) is controversial. The aim of the study was to assess the benefit of ICT with docetaxel, cisplatin and 5-fluorouracil (5-FU) (TPF) when combined with concurrent cisplatin chemoradiotherapy (CRT) for HNSCC. MATERIALS AND METHODS: Patients with HNSCC treated between January 2005 and December 2010 with radical intent with either TPF or cisplatin and 5-FU (PF) ICT and documented intention to proceed with concurrent cisplatin CRT were identified retrospectively. The use and choice of ICT regimen was at the clinician's discretion. In total, 68 patients treated with TPF were identified and were matched for T and N stage and tumour site to 68 patients treated with PF. A survival analysis was carried out using Kaplan-Meier and the Cox proportional hazards model. RESULTS: The median follow-up was 29.9 versus 36.3 months for the TPF and PF groups, respectively. Three year locoregional relapse-free survival (RFS), distant RFS, RFS, cancer-specific survival and overall survival rates for the TPF and PF groups were 84.2, 91.6, 82.6, 81.3 and 74.9% versus 73.7, 84.9, 71.9, 72.1 and 62.9%, respectively. On multivariate analysis, treatment with TPF predicted for improved locoregional RFS (P = 0.03) and overall survival (P = 0.05). CONCLUSION: The addition of docetaxel to a cisplatin doublet ICT regimen before concurrent CRT may improve disease control for locally advanced HNSCC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Quimiorradioterapia , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Docetaxel , Feminino , Fluoruracila/administração & dosagem , Humanos , Quimioterapia de Indução , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Taxa de Sobrevida , Taxoides/administração & dosagem , Resultado do Tratamento
8.
J Dairy Sci ; 96(6): 3817-24, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23567055

RESUMO

The aim of this study was to test Ovsynch (OVS) versus modified OVS (decreasing the interval between first GnRH and PGF2α to 6d) protocols on pregnancy per artificial insemination (AI) and OVS outcomes in cyclic dairy cows. Cyclic cows (n=920) were assigned to 1 of 2 groups: the OVS7 group (n=459) received the OVS protocol [GnRH treatment, PGF2α treatment 7d later, a second GnRH (GnRH2) treatment 56 h later, and timed AI (TAI) 16 to 18 h after the GnRH2 treatment], and the OVS6 group (n=461) received a modified OVS protocol, in which the interval between the first GnRH and PGF2α was decreased to 6d (GnRH treatment, PGF2α treatment 6d later, GnRH2 treatment 56 h later, and TAI 16 to 18h after the GnRH2 treatment). The response to the first GnRH of OVS was similar between OVS7 (54.5%, 250/459) and OVS6 (54.2%, 250/461) groups. The ovulatory response to GnRH2 of OVS was higher in OVS6 (91.3%, 421/461) than OVS7 (84.5%, 388/459). The follicle size (mean ± standard error of the mean) at the time of TAI was smaller in OVS6 (15.23 ± 0.11 mm) than OVS7 (16.04 ± 0.11 mm). When all cows were evaluated, the pregnancy per AI at 31 d tended to be lower in OVS6 (38.0%, 175/461) than in OVS7 (43.8%, 201/459). Moreover, the pregnancy per AI at 31 d was lower in OVS6 (40.9%, 172/421) compared with OVS7 (50.3%, 195/388) in synchronized cows. In conclusion, although the modified OVS protocol decreased the follicle size at the time of AI and increased the ovulatory response to GnRH2 of OVS, it unexpectedly reduced fertility in cyclic lactating dairy cows.


Assuntos
Dinoprosta/administração & dosagem , Sincronização do Estro/métodos , Hormônio Liberador de Gonadotropina/administração & dosagem , Inseminação Artificial/veterinária , Indução da Ovulação/veterinária , Animais , Bovinos , Feminino , Lactação , Folículo Ovariano/diagnóstico por imagem , Gravidez , Progesterona/sangue , Fatores de Tempo , Ultrassonografia
9.
J Dairy Sci ; 95(12): 7186-94, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23021759

RESUMO

The aim of this study was to evaluate the efficiency of presynchronization with GnRH and PGF(2α) or with progesterone on overall Ovsynch (OVS) outcomes in noncyclic dairy cows. Cows were scanned 7 d apart with ultrasonography to determine cyclicity. Noncyclic cows (n=281; no corpus luteum on ovaries at both examinations) were randomly divided into 3 groups. In the GP group (n=108), the cows received GnRH and PGF(2α) (PGF) administrations 7 d apart, and OVS was started 11 d after PGF (GnRH-7 d-PGF-11 d-OVS). In the P4 group (n=90), the cows were treated for 7d with an intravaginal progesterone (P4) implant (PRID), and then OVS was started 11 d after removal of the implant (7d PRID-11 d-OVS). The control group (CON, n=83) did not receive any presynchronization, and OVS was started at the same time as in the other groups (18 d-OVS). The percentage of cows that became cyclic at the beginning of OVS was lower in the CON group (38.6%; 32/83) than in the presynchronization groups (66.7%, 72/108 in GP; 71.1%, 64/90 in P4). The response to the first GnRH of OVS did not differ among groups (63.9%, 53/83 in CON; 67.6%, 73/108 in GP; 63.3%; 57/90 in P4), and synchronization rates were similar among the groups (74-82%). The cows that responded to presynchronization treatments (GP or P4) had higher pregnancy per artificial insemination (P/AI) than did nonresponding cows. Pregnancy per AI at 31 d did not differ between groups (30.1%, 25/83 in CON; 43.5%, 47/108 in GP; and 35.6%, 32/90 in P4). However, CON cows (24.1%, 20/83) had lower P/AI at 62 d than GP cows (41.7%, 45/108). Embryonic loss was higher in CON (20%, 5/25) compared with the P4 group (3%, 1/32). The administration of GnRH followed by PGF or exogenous progesterone (PRID) similarly increased the percentage of cows that became cyclic before Ovsynch in noncyclic cows, but fertility did not improve. However, the cows that responded to presynchronization had higher fertility rates than the nonresponding cows.


Assuntos
Dinoprosta/farmacologia , Sincronização do Estro/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Progesterona/farmacologia , Animais , Bovinos/fisiologia , Corpo Lúteo/diagnóstico por imagem , Indústria de Laticínios/métodos , Estro/efeitos dos fármacos , Feminino , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Gravidez , Ultrassonografia
10.
Theriogenology ; 78(8): 1830-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22968033

RESUMO

The aim of this study was to evaluate the effect of presynchronization with or without the detection of estrus on first service pregnancy per artificial insemination (P/AI) and on Ovsynch outcome in lactating dairy cows. A total of 511 cows were divided randomly but unevenly into 3 treatment groups at 44 to 50 days in milk (DIM). Ovsynch was started at the same time (69 to 75 DIM) in all three groups. Cows in the Ovsynch group (CON, N = 126) received no presynchronization before Ovsynch, and all cows were bred by timed AI (TAI). Cows in the presynchronization with estrus detection (PED) and the presynchronization with only TAI (PTAI) groups received two doses of prostaglandin F(2α) (PGF) 14 days apart, starting at 44 to 50 DIM. Ovsynch was initiated 11 days after the second PGF treatment. Cows in the PED group (N = 267) received AI if estrus was detected after either PGF injection. Cows that were not determined to be in estrus after PGF injection received Ovsynch and TAI. Cows in the PTAI group (N = 118) were not inseminated to estrus, with all cows receiving TAI after Ovsynch. The ovulatory response to the first GnRH injection administered as part of Ovsynch differed (P = 0.002) among treatment groups (83.1% in PTAI, 72.6% in PED, and 62.7% in CON). However, the ovulatory response to the second injection of GnRH during Ovsynch did not differ among treatment groups. Of the 267 PED cows, a total of 132 (49.4%) exhibited estrus and were inseminated. The P/AI at the 31-day pregnancy diagnosis was similar between the cows in the PED group with AI after estrus detection (37.9%; 50/132) and those bred with TAI (34.1%; 46/135). The P/AI in the CON group (46.8%; 59/126) was greater (P < 0.05) than that in the PED group (36.0%; 96/267). In addition, the P/AI in the CON group was greater (P = 0.04) than that in the PED cows receiving TAI (34.1%; 46/135) but less than that in the PED cows bred to estrus (37.9%; 50/132) (P = 0.16). At the 31-day pregnancy diagnosis, the cows in the PTAI group had greater P/AI (55.9%; 66/118) than both those in the PED group (P < 0.01; either estrus or TAI) and those in the CON group (P = 0.08). Thus, presynchronization with PGF (PTAI) increased the ovulatory response to Ovsynch and improved P/AI in dairy cows. Interestingly, the breeding of cows to estrus during presynchronization reduced fertility to the TAI and overall fertility, including cows bred to estrus and TAI. These results indicate that maximal fertility is obtained when all cows receive TAI after the presynchronization protocol.


Assuntos
Bovinos/fisiologia , Sincronização do Estro/métodos , Fertilidade , Inseminação Artificial/veterinária , Lactação , Indução da Ovulação/veterinária , Animais , Cruzamento/métodos , Dinoprosta/administração & dosagem , Detecção do Estro , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Inseminação Artificial/métodos , Indução da Ovulação/métodos , Gravidez , Fatores de Tempo , Resultado do Tratamento
11.
Reprod Domest Anim ; 46 Suppl 3: 11-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21854457

RESUMO

Dry period and early post-partum management are decisive factors for fertility in lactating dairy cows. Previous studies have shown that decreased dry matter intake (DMI) and increased non-esterified fatty acids (NEFA) negatively affect fertility and subsequent milk production. The traditional dry period decreases DMI prior to parturition, resulting in a decrease in energy intake. A negative energy balance increases NEFA concentration, and increased NEFA may impair the immune system, especially by decreasing neutrophil function prior to parturition. Earlier studies have shown that post-partum health disorders, including retained placenta and metritis, were correlated with periparturient neutrophil function. In addition, decreased DMI is also linked to a reduced body condition score (BCS) in dairy cows. These events in the periparturient period negatively affect fertility. Some manipulation, such as shortening the dry period, may be a solution to increased DMI in the periparturient period, preventing post-partum disorders and subsequent fertility issues. This article aims to explain the effects of shortening the dry period on reproduction and early post-partum treatments to improve fertility. In addition, timed artificial insemination protocols will be discussed for use during the post-partum period to improve fertility in dairy cows.


Assuntos
Criação de Animais Domésticos/métodos , Bovinos/fisiologia , Fertilidade/fisiologia , Lactação/fisiologia , Período Pós-Parto/fisiologia , Animais , Feminino , Fertilidade/efeitos dos fármacos , Gravidez
12.
J Dairy Sci ; 94(4): 1784-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21426967

RESUMO

The Ovsynch protocol was designed to synchronize ovulation, thereby allowing timed artificial insemination (TAI) of all cows without detection of estrus. However, the effectiveness of Ovsynch in different breeds of dairy cows has not been previously compared. The aim of this study was to compare the response to Ovsynch in cycling lactating Holstein-Friesian (HF) and Swedish Red (SR) dairy cows. A total of 495 cyclic cows (n=347 HF, n=148 SR) were housed together and treated with Ovsynch (GnRH-7 d-PGF2α-56 h-GnRH-16 to 18 h-TAI). Ovulatory responses, synchronization rate, maximal follicle size at the time of AI, and percentage of pregnant cows per AI (P/AI at 31 and 62 d after AI) were compared between breeds. Ultrasonography was performed during Ovsynch at first GnRH, PGF2α, at time of AI, and 7 d after AI. Ovulatory response and synchronization rate were similar in HF versus SR cows (60.2 vs. 62.2%; 88.4 vs. 88.5%, respectively). Cows that ovulated to the first GnRH of Ovsynch had smaller follicle size at AI (15.9±0.1 vs. 16.4±0.2 mm). Maximal follicle size at AI was greater for HF (16.4±2.2 mm) than SR (15.5±2.3 mm) cows. The P/AI was greater for SR than HF cows at the 62-d pregnancy diagnosis (56.1 vs. 46.1%). In addition, pregnancy loss between 31 and 62 d of pregnancy was greater in HF (10.1%) than SR (3.5%) cows. Fertility was less in HF cows during the hot season (57.7 in cold vs. 38.1% in the hot season), whereas such a decrease was not observed in SR (60.0 in cold vs. 53.5% in the hot season) cows. Thus, although the GnRH treatments of Ovsynch were equally effective in SR and HF cows, pregnancy outcomes (P/AI at d 62 and pregnancy survival) were greater in SR than HF cows, and P/AI in SR cows was not compromised during the hot season as was found for HF cows.


Assuntos
Bovinos/fisiologia , Sincronização do Estro/métodos , Inseminação Artificial/veterinária , Animais , Ciclo Estral/fisiologia , Feminino , Inseminação Artificial/métodos , Lactação/fisiologia , Folículo Ovariano/anatomia & histologia , Ovulação/fisiologia , Gravidez , Taxa de Gravidez , Especificidade da Espécie
13.
Theriogenology ; 74(4): 602-7, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20494429

RESUMO

Ovulatory response to the first GnRH of Ovsynch is a very important factor for determining the outcome of a successful synchronization. The aim of the present study was to develop a protocol to increase the percentage of cows that ovulated in response to the first administration of Ovsynch. This study was designed to compare ovulation rates in response to GnRH or hCG at the beginning of Ovsynch and to evaluate the effects of this manipulation on pregnancy. Cows (n = 371) with corpus luteum (CL) and at least one follicle greater than 10 mm diameter size on either ovary were included in the study. Cows were divided into two groups. The Ovsynch protocol began with GnRH (10 mug) in the GPG group (n = 161; GnRH-7d-PGF2alpha-56h-GnRH-18h-AI), whereas in the HPG group, the first GnRH of the Ovsynch was replaced with 1500 IU hCG (n = 210; hCG-7d-PGF2alpha-56h-GnRH-18h-AI). Ovarian ultrasonography was performed at the times of GnRH or hCG and of PGF2alpha administration, at the time of artificial insemination (AI) and seven days after AI, to determine ovulation. Maximal follicle size at the beginning of the Ovsynch did not affect on response to the first GnRH/hCG treatment. Conception rate (31 d) was 0.6 times more likely to be higher (P < 0.001) in cows that responded to the first hormonal administration of Ovsynch than in those that did not respond (95% CI = 0.29-0.71). Conception rate was found to be different between the HPG (37.6%, 79/210) and the GPG groups (48.4%, 78/161). Thus, beginning of the Ovsynch protocol with hCG did not increase ovulation and conception rate in lactating dairy cows, suggesting that hCG is not a suitable replacement of the first GnRH of Ovsynch. However, our results do show that increasing the ovulation rate in response to the first hormonal administration of Ovsynch can have a significant effect on conception rate.


Assuntos
Bovinos/fisiologia , Gonadotropina Coriônica/farmacologia , Fertilização/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Ovulação/efeitos dos fármacos , Animais , Feminino , Lactação , Gravidez
15.
Chemosphere ; 66(1): 130-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16784768

RESUMO

Natural pumice particles were used as granular support media and coated with iron oxides to investigate their adsorptive natural organic matter (NOM) removal from waters. The impacts of natural pumice source, particle size fraction, pumice dose, pumice surface chemistry and specific surface area, and NOM source on the ultimate extent and rate of NOM removal were studied. All adsorption isotherm experiments were conducted employing the variable-dose completely mixed batch reactor bottle-point method. Iron oxide coating overwhelmed the surface electrical properties of the underlying pumice particles. Surface areas as high as 20.6m(2)g(-1) were achieved after iron coating of pumice samples, which are above than those of iron coated sand samples reported in the literature. For all particle size fractions, iron coating of natural pumices significantly increased their NOM uptakes both on an adsorbent mass- and surface area-basis. The smallest size fractions (<63 microm) of coated pumices generally exhibited the highest NOM uptakes. A strong linear correlation between the iron contents of coated pumices and their Freundlich affinity parameters (K(F)) indicated that the enhanced NOM uptake is due to iron oxides bound on pumice surfaces. Iron oxide coated pumice surfaces preferentially removed high UV-absorbing fractions of NOM, with UV absorbance reductions up to 90%. Control experiments indicated that iron oxide species bound on pumice surfaces are stable, and potential iron release to the solution is not a concern at pH values of typical natural waters. Based on high NOM adsorption capacities, iron oxide coated pumice may be a promising novel adsorbent in removing NOM from waters. Furthermore, due to preferential removal of high UV-absorbing NOM fractions, iron oxide coated pumice may also be effective in controlling the formation of disinfection by-products in drinking water treatment.


Assuntos
Ferro/química , Compostos Orgânicos/química , Silicatos/química , Adsorção , Microscopia Eletrônica de Varredura , Compostos Orgânicos/isolamento & purificação , Tamanho da Partícula , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos
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