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1.
J Dairy Sci ; 106(2): 1301-1314, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36460510

RESUMO

On-farm euthanasia is complicated in that farmers have to make the decision to end the life of an animal they are caring for. Studies have shown that some culling decisions are made too late, which results in animal welfare issues. However, information about on-farm euthanasia methods and the decision process leading to the euthanasia of an animal is limited. Additionally, emotions and feelings are involved in the decision and the act of euthanasia. The objectives of this study were to describe current practices related to on-farm euthanasia performed by Canadian dairy farmers and to assess the emotions and complex feelings surrounding the act. A cross-sectional study design was used to gather this information through an online questionnaire completed exclusively by Canadian dairy farmers. Data were analyzed descriptively using frequencies, and associations between the participants' characteristics and their practices and emotions regarding on-farm euthanasia were assessed using logistic regression models. A total of 479 dairy farmers from 5 provinces answered the survey. The most commonly used primary method of on-farm euthanasia was a firearm (>70%). Unacceptable euthanasia methods, such as standard 0.22-caliber long rifle for adult cows or no adjunct method following the use of captive bolt, were used by 25%, 18%, and 58% of the participants for calves, replacement animals, and dairy cows, respectively. Ninety-four percent of the participants reported that the farm owner was the person who always or often made the euthanasia decisions. In addition, 32% of the participants reported that the veterinarian always examined the animal before performing euthanasia, 51% reported at least one person received training to perform euthanasia, and 16% reported having a decision tree for euthanasia. Some participants (17%) were troubled with the responsibility for ending the life of their animals, and 19% perceived other people on the farm to be uncomfortable with performing euthanasia. Half of the participants reported that people performing euthanasia on the farm felt at least one related painful emotion or complex feeling, and half reported they had at least one reason to feel anxiety or unease concerning euthanasia. The results of this study showed gaps such as the limited use of acceptable euthanasia methods and decision trees by Canadian dairy farmers, low availability of on-farm training for euthanasia, and variable involvement of veterinarians.


Assuntos
Indústria de Laticínios , Fazendeiros , Feminino , Animais , Bovinos , Humanos , Fazendeiros/psicologia , Fazendas , Canadá , Estudos Transversais , Indústria de Laticínios/métodos , Eutanásia Animal , Emoções
2.
J Dairy Sci ; 97(6): 3364-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24657085

RESUMO

The objectives of this study were (1) to determine the correlations between blood ß-hydroxybutyrate (BHBA) and milk components [BHBA, acetone, fat, protein, and fat:protein (F:P) ratio], and (2) to establish optimal thresholds for milk components to predict hyperketonemia in dairy cows. Data on 163 cows from 37 herds were used in this cross-sectional study. Herds were visited once during the study period, and cows between 2 and 90 d in milk were blood sampled within 4h of milk sampling for the Dairy Herd Improvement test. Blood BHBA concentrations were measured using a cow-side electronic meter, Precision Xtra, which was considered the gold standard test in this study. Milk BHBA and acetone concentrations were measured in Dairy Herd Improvement milk samples by flow-injection analysis; whereas, milk fat and protein were tested using Fourier transform infrared spectroscopy. Hyperketonemia was defined by a blood BHBA concentration ≥ 1.4 mmol/L. The prevalence of hyperketonemia (based on blood BHBA values) in this study population was 21.0%. Pearson correlation coefficients between blood BHBA and milk BHBA, acetone, fat, protein, and F:P ratio were 0.89, 0.73, 0.21, 0.04, and 0.17, respectively. Receiver operating characteristic curves were generated and thresholds for each individual milk component were determined based on the maximal sum of sensitivity and specificity. Optimal threshold values for hyperketonemia were milk BHBA ≥ 0.20 mmol/L, acetone ≥ 0.08 mmol/L, fat ≥ 4.2%, and F:P ratio ≥ 1.3. Based on these thresholds, milk BHBA and acetone had greater sensitivity (84 and 87%, respectively) and greater specificity (96 and 95%, respectively) than the other milk components (fat, protein, and F:P). Series and parallel testing slightly improved the accuracy of milk BHBA and acetone values to predict hyperketonemia. A multivariable model that accounted for milk BHBA and milk acetone values simultaneously had the highest accuracy of all tested models for predicting hyperketonemia. These results support that milk BHBA and milk acetone values from flow-injection analysis are accurate diagnostic tools for hyperketonemia in dairy cows and could potentially be used for herd-level hyperketonemia surveillance programs.


Assuntos
Doenças dos Bovinos/diagnóstico , Corpos Cetônicos/análise , Cetose/veterinária , Leite/química , Ácido 3-Hidroxibutírico/sangue , Acetona/análise , Animais , Bovinos , Doenças dos Bovinos/sangue , Estudos Transversais , Gorduras na Dieta/análise , Feminino , Cetose/sangue , Cetose/diagnóstico , Modelos Logísticos , Proteínas do Leite/análise , Análise Multivariada , Sensibilidade e Especificidade , Espectroscopia de Infravermelho com Transformada de Fourier/veterinária
3.
J Dairy Sci ; 95(6): 3110-24, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22612947

RESUMO

Objectives of this study were to identify the manageable risk factors associated with the lactational incidence, elimination, and prevalence of coagulase-negative staphylococci (CNS) intramammary infections (IMI) while taking into account the difficulties inherent to their diagnosis. A second objective was to evaluate the effect of CNS IMI misclassification in mastitis research. A cohort of 90 Canadian dairy herds was followed throughout 2007 to 2008. In each herd, series of quarter milk samples were collected from a subsample of cows and bacteriological culture was performed to identify prevalent, incident, and eliminated CNS IMI. Practices used on farms were captured using direct observations and a validated questionnaire. The relationships between herd CNS IMI prevalence and herd incidence and elimination rates were explored using linear regression. Manageable risk factors associated with the prevalence, incidence, or elimination of CNS IMI were identified via Bayesian analyses using a latent class model approach, allowing adjustment of the estimates for the imperfect sensitivity and specificity of bacteriological culture. After adjustment for the diagnostic test limitations, a mean CNS IMI quarter prevalence of 42.7% [95% confidence interval (CI): 34.7, 50.1] and incidence and elimination rates of 0.29 new IMI/quarter-month (95% CI: 0.21, 0.37) and 0.79 eliminated IMI/quarter-month (95% CI: 0.66, 0.91), respectively, were observed. Considerable biases of the estimates were observed when CNS IMI misclassification was ignored. These biases were important for measures of association with risk factors, were almost always toward the null value, and led to both type I and type II errors. Coagulase-negative staphylococci IMI incidence appeared to be a stronger determinant of herd IMI prevalence than IMI elimination rate. The majority of herds followed were already using blanket dry cow treatment and postmilking teat disinfection. A holistic approach considering associations with all 3 outcomes was used to interpret associations between manageable risk factors and CNS IMI. Sand and wood-based product bedding showed desirable associations with CNS IMI compared with straw bedding. Quarters of cows that had access to pasture during the sampling period had lower odds of acquiring a new CNS IMI and of having a prevalent CNS IMI. Many practices showed an association with only one of the CNS outcomes and should, therefore, be considered with caution.


Assuntos
Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/classificação , Animais , Canadá/epidemiologia , Bovinos , Feminino , Incidência , Estudos Longitudinais , Mastite Bovina/diagnóstico , Mastite Bovina/epidemiologia , Leite/microbiologia , Prevalência , Sorotipagem , Infecções Estafilocócicas/microbiologia
4.
J Dairy Sci ; 95(3): 1283-300, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22365211

RESUMO

Staphylococcus aureus intramammary infections (IMI) are a major cause of mastitis on farms worldwide. Incidence and elimination rates are the key determinants of prevalence of Staph. aureus, and risk factors associated with these rates must be identified, prioritized, and controlled to obtain long-term reduction in prevalence. The objectives of this study were to identify manageable risk factors associated with the lactational incidence, elimination, and prevalence of Staph. aureus IMI. A cohort of 90 Canadian dairy farms was recruited and followed in 2007 and 2008. Quarter milk samples were collected repeatedly from a selection of cows, and bacteriological culture was realized to assess incidence, elimination, and prevalence of Staph. aureus IMI. Practices used on farms were measured using direct observations and a validated questionnaire. A linear regression model was used to explore the relationship between herd IMI prevalence and incidence and elimination rates. Multilevel logistic regression models were used to compute measures of associations between practices used on farms and IMI incidence, elimination, and prevalence. The herd incidence rate was the most important predictor of herd IMI prevalence: a reduction of the incidence rate equivalent to its interquartile range (0.011 new IMI/quarter-month) was associated with a prevalence reduction of 2.2 percentage points; in comparison, an equivalent increase of the elimination rate by its interquartile range (0.36 eliminated IMI/quarter-month) resulted in a prevalence reduction of 0.4 percentage points. Postmilking teat disinfection and blanket dry-cow therapy were already implemented by most herds. Most of the practices associated with Staph. aureus IMI incidence were related to milking procedures. Among these, wearing gloves during milking showed desirable associations with IMI incidence, elimination, and prevalence. Similarly, adequate teat-end condition and use of premilking teat disinfection were associated with lower IMI incidence and prevalence. The initial herd prevalence of Staph. aureus IMI was positively associated with subsequent IMI incidence. This indicates that, in some situations, an initial reduction of the pool of infected quarters could be justified. Some housing practices were associated with IMI incidence, elimination, or prevalence. The effects of these latter practices, however, were often influenced by specific cow characteristics such as parity or days in milk. These results highlight the importance of good milking practices to prevent Staph. aureus IMI acquisition and, therefore, reduce their prevalence.


Assuntos
Mastite Bovina/epidemiologia , Infecções Estafilocócicas/veterinária , Animais , Bovinos , Indústria de Laticínios/métodos , Feminino , Incidência , Mastite Bovina/prevenção & controle , Paridade , Prevalência , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle
5.
J Dairy Sci ; 92(2): 777-81, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19164691

RESUMO

This field trial evaluated the effects of dietary supplementation with 16 mg/kg (based on total dry matter intake) of monensin sodium on bulk tank milk fat percentage (MFP) of commercial dairy herds. Interactions between monensin and nutritional factors on MFP were studied. The trial was conducted in 47 Holstein dairy herds in Québec, Canada, between November 2005 and May 2006. The herd was the unit of interest. Enrolled herds were followed for a 7-mo period. Monensin treatment was randomly allocated in a crossover design where monensin was supplemented to the lactating dairy cow diet for a consecutive 12-wk period. Twenty-four herds were allocated to monensin treatment for the first period of trial, and 23 herds were allocated for the second period. Diet composition and ration physically effective particle level were collected every 8 wk. Milk fat percentage data were retrieved from weekly bulk tank measures. Data were analyzed in linear mixed models using repeated measures within herd where MFP was considered the outcome variable. In addition to the main effect of monensin treatment, the following covariates were forced a priori into all statistical models: treatment period, weekly herd mean parity, and weekly herd mean days in milk. The majority of herds were fed a total mixed ration (n = 29) and were housed in tie-stalls (n = 42). Monensin significantly decreased bulk tank MFP by 0.12 percentage points. The reduction of MFP associated with monensin was larger for herds having a diet high (>39.7%) in nonfiber carbohydrates, having a low level of physically effective particles in ration (>45.0%; >or=8 mm), and not feeding dry hay as first meal in the morning. Significant interactions between monensin and nutritional factors on bulk tank MFP were related to nonfiber carbohydrate and fiber concentrations in the diet.


Assuntos
Bovinos/fisiologia , Dieta/veterinária , Suplementos Nutricionais , Gorduras/análise , Leite/química , Leite/efeitos dos fármacos , Monensin/farmacologia , Animais , Estudos Cross-Over , Indústria de Laticínios , Feminino , Análise dos Mínimos Quadrados , Distribuição Aleatória
6.
Theriogenology ; 89: 305-317, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28043367

RESUMO

The objective of this study was to assess the efficacy of cephapirin intrauterine treatment preceding a timed artificial insemination protocol in lactating dairy cows with purulent vaginal discharges (PVDs). Holstein dairy cows (n = 1247) from 18 herds were enrolled in a controlled randomized clinical trial. At 34 days in milk (DIM; ±7 days), cows had a genital examination (transrectal palpation, vaginoscopy, and uterine bacteriology). They were randomly assigned to either the control group (CONT, no treatment) or the treatment group (CEPH) consisting of 1 intrauterine infusion of 500-mg cephapirin benzathine (RCL) (Metricure, Merck Animal Health, Montreal, Canada) regardless of the uterine health status. All cows were systematically enrolled in a presynch-ovsynch protocol for the first insemination. A second genital examination was made 2 weeks later. Cows that received any systemic or local antibiotics 10 days prior sampling to the end of the synchronization protocol were excluded from the study. Reproductive data of cows were collected for at least 300 DIM, entered in a databank, and validated (health record management software, DSAHR). Pregnancy diagnosis was done by transrectal palpation at the routinely scheduled veterinarian visits. On the basis of the highest sum of sensibility and specificity for pregnancy status at 120 DIM, the optimal cutoff for vaginal discharge score was determined as the presence of cloudy discharge with or without purulent material (PVD+, score 2). With a prevalence of 21.6% at 34 DIM, PVD+ was detrimental to the first-service conception rate (FSCR; PVD+: 26 ± 5%; PVD-: 40 ± 3%; P = 0.02). The negative effect of PVD+ was indicated by a hazard ratio of 0.72 (chi-square = 8.58; P < 0.01; 95% confidence interval = 0.56-0.91). Treatment with cephapirin was associated with a significant improvement of the FSCR in PVD+ cows (PVD+ CEPH: 36 ± 5%, PVD+ CONT: 23 ± 5%; P < 0.05), although it did not produce a considerable clinical cure based on the second examination. Thus, a longer period of time following treatment may be needed to properly assess the efficacy of intrauterine treatment in PVD+ cows. In conclusion, cephapirin intrauterine treatment in PVD+ cows at 34 DIM considerably improves reproductive performance compared with untreated PVD+ cows.


Assuntos
Antibacterianos/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Cefapirina/uso terapêutico , Doenças Uterinas/veterinária , Descarga Vaginal/veterinária , Animais , Bovinos , Feminino , Doenças Uterinas/tratamento farmacológico , Útero/microbiologia , Descarga Vaginal/tratamento farmacológico
7.
Prev Vet Med ; 75(3-4): 267-79, 2006 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-16769141

RESUMO

The objective of this study was to investigate if treatment of cows with eprinomectin around calving had any beneficial effects on the calving to first artificial insemination interval, calving to conception interval, and number of services per conception in totally- and semi-confined dairy herds. In totally-confined herds lactating- and dry-cows were housed throughout the summer and had no access to pasture. In semi-confined herds lactating- and dry-cows had limited outdoor exposure to a small pasture or paddock but were still fed a ration that met all their nutritional requirements. The study was carried out between February 2002 and February 2003 in 35 herds (2381 cows) located in Quebec, Ontario and Minnesota (USA) participating in a larger clinical trial. The herds kept electronic reproduction records. Cows were randomly allocated to receive eprinomectin or a placebo, with treatment being administered on or close to the day of calving. Monthly bulk tank milk samples from each farm were tested with an indirect ELISA using a crude Ostertagia ostertagi antigen and these data were averaged over the study year. The optical density ratio (ODR) values were then dichotomized into high and low using a cut-point of 0.50. Treatment effects were analyzed using Cox proportional hazards survival models with herd frailty effects for calving to conception and calving to first service intervals. Aalen's linear hazards model was used to investigate time-varying effects in the Cox models. A random effects poisson regression model was used to model the number of services per conception. Other predictor variables tested in the models were lactation number, calving season, study site, peak milk production, ODR and the lactating- and dry-cow housing variables. Overall, there was no significant effect of treatment on the three indices of reproductive performance. The effect of season of calving depended on how much time had passed since calving. Presumably this effect reflected a seasonal effect at the time of breeding. Hazard of conception in younger cows was higher than in older cows. Early bred cows tended to have a higher number of inseminations per conception than those bred late. The results of the study suggested that eprinomectin treatment at calving was not beneficial to reproduction.


Assuntos
Criação de Animais Domésticos/métodos , Anti-Helmínticos/uso terapêutico , Bovinos/fisiologia , Ivermectina/análogos & derivados , Reprodução , Animais , Anti-Helmínticos/administração & dosagem , Antígenos de Helmintos/análise , Feminino , Ivermectina/administração & dosagem , Ivermectina/uso terapêutico , Lactação/fisiologia , Leite/imunologia , Leite/metabolismo , Ostertagia/imunologia , Poaceae , Gravidez , Modelos de Riscos Proporcionais , Distribuição Aleatória , Reprodução/efeitos dos fármacos , Reprodução/fisiologia , Fatores de Tempo
8.
Vet Parasitol ; 98(4): 309-14, 2001 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-11423188

RESUMO

This field trial was conducted to test the effect of treatment with a sustained-release ivermectin bolus on first lactation milk production (projected to 305 days) and milk composition (percent fat and protein) in breeding-aged Holstein heifers. From 12 herds, 96 heifers were randomly allocated at turnout to treatment with a commercially available ivermectin bolus (n=49) or untreated control (n=47) groups. Animals were weighed at turnout, mid-season, and at the end of the grazing season. Fecal samples were taken and nematode eggs counted. Projected 305 days milk production, fat and protein content were retrieved from PATLQ reports (Quebec DHI records) for heifers that calved during the subsequent 10 months. The heifers had a mean weight of 409 and 404 kg at turnout, respectively, for control and treated groups. Nematode egg excretion was relatively low (mean of 10 egg/g (EPG) for controls at housing) throughout the pasture season. The average daily gain (ADG) and total weight gain (TWG) over the entire pasture season was found to be higher in treated heifers compared to controls (ADG: difference=0.08 kg per day, P=0.010; TWG: difference=12.82 kg, P=0.013). Taking into account a possible farm effect, the 305 days milk production for IVOMEC SR bolus-treated heifers was significantly higher than for untreated animals (mean+/-S.D.; 348+/-476 kg; t-test=2.31, P<0.05). Overall, 8 of the 10 remaining farms in the study demonstrated a positive milk production difference in treated (n=34) versus control heifers (n=33). The results of this study suggest that preventive treatment of breeding-aged, grazing dairy heifers with a sustained-release ivermectin bolus provides a significant weight-gain which may translate to a significant milk production advantage, even in situations with commercial utilization of moderately contaminated pastures.


Assuntos
Antiprotozoários/uso terapêutico , Doenças dos Bovinos/prevenção & controle , Bovinos/parasitologia , Controle de Doenças Transmissíveis , Ivermectina/uso terapêutico , Lactação , Animais , Antiprotozoários/administração & dosagem , Peso Corporal , Cruzamento , Controle de Doenças Transmissíveis/métodos , Preparações de Ação Retardada , Feminino , Ivermectina/administração & dosagem
9.
Prev Vet Med ; 56(2): 165-77, 2002 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-12450687

RESUMO

A clinical trial was carried out in two provinces of Canada to investigate the effect of treatment with eprinomectin at calving on production parameters in adult dairy cattle in 1999-2000. One of the objectives of this study was to evaluate the impact of treatment on reproductive performance as measured by: calving-to-conception interval, calving-to-first service interval and number of services per conception. The ability of an indirect ELISA using a crude adult Ostertagia ostertagi antigen to predict response to treatment also was evaluated. All lactating cows in 20 dairy herds were allocated randomly to receive either eprinomectin pour-on or placebo at calving. Information on reproductive parameters was obtained from computerised cow records. Survival models were used to evaluate the effect of treatment on the two intervals and a Poisson model was used to evaluate the number of services to conception. A total of 549 cows were included in these analyses. A marginally significant treatment effect on calving-to-conception interval was observed (hazard ratio=1.24, P=0.06) but not on calving-to-first service interval. A significant reduction in the number of breedings to conception for treated animals also was observed with a longer effect in cows with short interval to first service. Milk samples from a subset of 109 late-lactation cows were tested for antibodies against O. ostertagi. The ELISA optical-density ratio (ODR) values obtained between 120 days before calving and drying off were categorised as high ODR (>or=0.5) and low ODR (<0.5). Among untreated animals, the hazard of conception was lower (hazard ratio=0.38, 95% CI=[0.19,0.75]) for high-ODR cows compared to low ODR cows suggesting that higher parasite burdens had an adverse effect on reproductive performance. Treated high-ODR cows had a hazard of conception equivalent to the hazard for all cows in the low-ODR group (indicating that treatment prevented the negative effect associated with these higher parasite burdens).


Assuntos
Anti-Helmínticos/farmacologia , Bovinos/crescimento & desenvolvimento , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Ostertagia/patogenicidade , Ostertagíase/prevenção & controle , Reprodução , Animais , Anti-Helmínticos/administração & dosagem , Antígenos de Helmintos/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Ivermectina/administração & dosagem , Ostertagia/imunologia , Ostertagia/isolamento & purificação , Ostertagíase/complicações , Gravidez , Sobrevida
10.
Can J Vet Res ; 55(1): 5-10, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1884284

RESUMO

The purpose of the study was to determine whether there were circadian variations in serum osteocalcin in normal horses and to determine whether it was important to regulate the time of blood sampling in clinical investigations. Osteocalcin or bone Gla-protein (BGP), alkaline phosphatase, total calcium, phosphate and total protein were studied over a 24 h period. Blood samples were taken every 60 min from nine adult Standardbred horses. There was a correlation between serum levels of alkaline phosphatase (r = 0.3, p less than 0.01), phosphate (r = 0.42, p less than 0.01) and serum osteocalcin levels. There was a very marked individual effect on serum levels of osteocalcin and alkaline phosphatase (p less than 0.01). This effect was present for phosphate levels but not significant for total calcium. The individual effect was lower and time effect was higher for serum osteocalcin if the subjects were divided into two age groups, one of horses of five years or less (n = 4) and a second group older than five years (n = 5). In both groups a circadian rhythmicity was observed. Serum osteocalcin showed a biphasic pattern. Levels were constant during daytime (light period) and underwent significant variations during the night (dark period), going through a nadir at 2000 h and through a maximum peak at 0500 h. It was concluded that in normal horses the blood osteocalcin level follows a circadian variation. Also daytime (light period) seems to be the more appropriate period for blood sampling.


Assuntos
Ritmo Circadiano , Cavalos/sangue , Osteocalcina/sangue , Prenhez/sangue , Fosfatase Alcalina/sangue , Animais , Proteínas Sanguíneas/análise , Cálcio/sangue , Feminino , Masculino , Fosfatos/sangue , Gravidez , Valores de Referência
11.
Can J Vet Res ; 67(4): 241-51, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14620860

RESUMO

This manuscript presents the results of a review of the effects of recombinant bovine somatotropin (rBST) on milk production, milk composition, dry matter intake, and body condition score that was carried out by an expert panel established by the Canadian Veterinary Medical Association (CVMA). The panel was established by the CVMA in response to a request from Health Canada in 1998 and their report was made public in 1999. A series of meta-analyses was used to combine data on production and nutrition related parameters that were extracted from all randomized clinical trials, which had been published in peer-reviewed journals or which were provided by Health Canada, from the submission by Monsanto for registration of rBST in Canada. A companion paper will present the results of the effects of the drug on measures of health, reproductive performance, and culling parameters. Recombinant bovine somatotropin was found to increase milk production by 11.3% in primiparous cows and 15.6% in multiparous cows; although there was considerable variation from study to study. While some statistically significant effects on milk composition (% butterfat, protein, and lactose) were found, they were all very small. Treatment increased dry matter intake by an average 1.5 kg/day during the treatment period and dry matter intake remained elevated on into the first 60 days of the subsequent lactation. Despite the increase in dry matter intake, treated animals had lower body condition scores at the end of the treatment period, and the reduced scores persisted through until the start of the subsequent lactation.


Assuntos
Bovinos/fisiologia , Ingestão de Alimentos/efeitos dos fármacos , Hormônio do Crescimento/farmacologia , Leite/efeitos dos fármacos , Animais , Composição Corporal/efeitos dos fármacos , Constituição Corporal , Canadá , Feminino , Lactação , Leite/química , Leite/metabolismo , Paridade
12.
Can J Vet Res ; 67(4): 252-64, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14620861

RESUMO

This manuscript presents the results of a review of the effects of recombinant bovine somatotropin (rBST) on dairy cattle health, reproductive performance, and culling, that was carried out by an expert panel established by the Canadian Veterinary Medical Association (CVMA). The panel was established by the CVMA in response to a request from Health Canada in 1998 and their report was made public in 1999. A series of meta-analyses was used to combine data on health-related parameters that were extracted from all randomized clinical trials that had been published in peer-reviewed journals or which were provided by Health Canada from the submission by Monsanto for registration of rBST in Canada. A companion paper (1) presents the estimates of the effect of the drug on production parameters. Recombinant bovine somatotropin was found to increase the risk of clinical mastitis by approximately 25% during the treatment period but there was insufficient data to draw firm conclusions about the effects of the drug on the prevalence of subclinical intra-mammary infections. Use of rBST increased the risk of a cow failing to conceive by approximately 40%. For cows which did conceive, there was no effect on services per conception and only a small increase in average days open (5 days). Use of the drug had no effect on gestation length, but the information about a possible effect on the risk of twinning was equivocal. Cows treated with rBST had an estimated 55% increase in the risk of developing clinical signs of lameness. Few studies reported data on culling, but based on those that did, there appeared to be an increase risk of culling evident in multiparous cows. Use of the drug in 1 lactation period appeared to reduce the risk of metabolic diseases (particularly ketosis) in the early period of the subsequent lactation.


Assuntos
Bovinos/fisiologia , Hormônio do Crescimento/farmacologia , Coxeadura Animal/epidemiologia , Mastite Bovina/epidemiologia , Reprodução/efeitos dos fármacos , Animais , Feminino , Cetose/prevenção & controle , Cetose/veterinária , Paridade , Prevalência , Fatores de Risco
13.
Can Vet J ; 30(6): 501-3, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17423347

RESUMO

GRANULOSA CELL TUMOR IN A HEIFER: CLINICAL, ENDOCRINOLOGICAL AND POSTMORTEM OBSERVATIONS A benign granulosa cell tumor was diagnosed in a 19 month old Holstein heifer. Granulosa cell tumors are the most common of the ovarian tumors in cattle. This animal showed no signs of nymphomania or virilism. The principal clinical signs were anestrus and mammary gland hypertrophy. Diagnosis was made by transrectal exam and later confirmed by post-mortem examination. High levels of estrogen and testosterone were present in the plasma and might explain the clinical signs observed in this heifer. The endocrine changes associated with granulosa cell tumors and possible clinical approaches are briefly discussed.

14.
Can Vet J ; 39(11): 701-5, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9818136

RESUMO

This field trial was designed to test the effect of treatment with a sustained-release ivermectin bolus on average daily and total weight gain in breeding age Holstein heifers under commercial pasture conditions in southern Quebec. One hundred and twelve heifers from 12 herds were randomly assigned at turnout either to treatment with a commercially-available ivermectin bolus or to remain as untreated controls. Ninety-six heifers, 49 treated animals and 47 controls, completed the trial. Animals were weighed at turnout, midseason, and at the end of the grazing season. Fecal samples were collected at each of these times and nematode eggs counted. Nematode egg excretion was relatively low throughout the pasture season, which was abnormally warm and dry until midsummer. Over the entire pasture season, average daily weight gain was higher in treated than in control animals (difference = 0.08 kg/day, P = 0.010). Total weight gain was also higher in treated animals than in control animals (difference = 12.82 kg, P = 0.013). The results of this study suggest that preventive treatment of breeding age, grazing dairy heifers with a sustained-release ivermectin bolus provides a significant weight gain advantage, in situations with moderate utilization of moderately contaminated pastures.


Assuntos
Antinematódeos/uso terapêutico , Ivermectina/uso terapêutico , Aumento de Peso/efeitos dos fármacos , Criação de Animais Domésticos , Animais , Bovinos , Preparações de Ação Retardada , Feminino , Quebeque , Estações do Ano
15.
Can Vet J ; 42(1): 38-44, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11195520

RESUMO

Two different deworming strategies based on the use of moxidectin, a broad spectrum endectocide with persistency against Ostertagia ostertagi, were evaluated in grazing dairy heifers. Eighty-four heifers unexposed to parasitic infection were randomly allocated to 3 different groups: untreated (Group 1), treated at 3 and 10 weeks after turnout with 0.5 mg/kg/body weight (BW) of topical moxidectin (Group 2), or treated at turnout and 10 weeks later with 0.5 mg/kg/BW of topical moxidectin (Group 3). The heifers were turned out on June 6 (Day 0) to a naturally contaminated pasture divided into 3 sections by an electrical fence. Each group of heifers was put on a different section of pasture. The trial ended when they were housed on October 29 (Day 143). The results of this experiment confirmed the beneficial effect of 2 strategic treatments with moxidectin pour-on under field conditions in Quebec. The parasitological parameters showed a statistical difference in terms of mean fecal egg counts between treated and control groups (ANOVA, P < or = 0.006). After turnout, pasture larval counts were consistently higher for Group 1 compared with counts for Group 2 or 3. All heifer groups gained weight during the trial period, but the weight gain profile of both treated groups was significantly higher than that of the untreated controls (ANOVA, P < 0.03). During the trial period, Group 2 and Group 3 gained 77.7 kg BW and 73.2 kg BW, respectively, while Group 1 gained only 57.9 kg BW, despite the fact that heifers of Group 1 received a greater quantity of supplementary feed while on pasture.


Assuntos
Antibacterianos/farmacologia , Antinematódeos/farmacologia , Doenças dos Bovinos/tratamento farmacológico , Ostertagia/efeitos dos fármacos , Ostertagíase/veterinária , Abomaso/parasitologia , Análise de Variância , Animais , Antibacterianos/uso terapêutico , Antinematódeos/uso terapêutico , Bovinos , Doenças dos Bovinos/prevenção & controle , Fezes/parasitologia , Feminino , Macrolídeos , Ostertagíase/tratamento farmacológico , Ostertagíase/prevenção & controle , Fatores de Tempo , Aumento de Peso/efeitos dos fármacos
16.
Sante Ment Que ; 9(1): 111-7, 1984.
Artigo em Francês | MEDLINE | ID: mdl-17093806

RESUMO

This article deals with the treatment of pre-orgasmic women. Following a short description of the evolution of therapies, the authors define pre-orgasm and its treatment. The authors then present the sequence of treatment sessions and the results obtained in relation to the following aspects: respect for rules and assiduity, age groups, reactions to exercises, relation to partner, methods of undermining, group climate, use of personal creativity and, finally, the effects of therapy on the life of the couple. In conclusion, the authors underline the generalizing effect, produced by improvement in sexual relations on several other aspects of the lives of participants, and on their couple relationship.

17.
J Dairy Sci ; 88(3): 929-37, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15738227

RESUMO

The objective of this study was to determine the effect of anthelmintic treatment at calving in herds that were totally or semiconfined during the summer. In totally confined herds, lactating and dry cows were housed throughout the summer and had no access to pasture. In semiconfined herds, lactating and dry cows had limited outdoor exposure to a small pasture or paddock but were still fed a ration that met all their nutritional requirements. The study was carried out between February 2002 and February 2003 in 65 herds enrolled with DHI and distributed in 4 regions in Canada and 1 state in the United States. Cows were randomly allocated to receive eprinomectin or a placebo, with treatment being administered on or close to day of calving. In May and June 2002, 8 fecal samples were collected from each farm and fecal egg counts (FEC) were determined. Monthly bulk tank milk samples from each farm were tested with an indirect ELISA using a crude Ostertagia ostertagi antigen. Monthly test-day milk production data were recorded for 200 d after calving. In general, FEC were very low (mean = 1 egg per gram, range = 0 to 27). Mean herd bulk milk ELISA optical density ratio (ODR) values for the whole year ranged between 0.22 and 0.80. The ODR values were dichotomized into high and low using a threshold of 0.5. Treatment effects were analyzed using a linear mixed model with herd and cow as random effects. The analysis was restricted to 4789 cows (23,956 test-day records) treated between 21 d before and 7 d after calving. Overall, there was no significant effect of treatment. However, there was a tendency for an interaction between treatment and ODR, as illustrated by a larger numerical difference in treated vs. untreated cows in high-ODR herds than in low-ODR herds. However, the confidence intervals for the treatment effects (kg/d of milk per cow) in high-ODR herds (-0.33 to 1.10) and in low-ODR herds (-0.53 to 0.14) were wide and included zero. Therefore, this study failed to show a beneficial effect of eprinomectin treatment in these totally or semiconfined herds.


Assuntos
Anti-Helmínticos/farmacologia , Bovinos/fisiologia , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Lactação/efeitos dos fármacos , Criação de Animais Domésticos/métodos , Animais , Antígenos de Helmintos/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/parasitologia , Feminino , Lactação/fisiologia , Leite/imunologia , Leite/metabolismo , Infestações por Ácaros/epidemiologia , Infestações por Ácaros/veterinária , Contagem de Ovos de Parasitas/veterinária , Doenças Parasitárias em Animais/tratamento farmacológico , Doenças Parasitárias em Animais/prevenção & controle , Poaceae , Gravidez
18.
J Dairy Sci ; 85(2): 397-405, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11913700

RESUMO

A total of 1317 Holstein cows from 45 farms in the Canadian provinces of Quebec, Prince Edward Island (PEI) and Ontario were enrolled in a randomized trial during 1998 and 1999 to further confirm the efficacy of a monensin controlled release capsule in preventing periparturient disease in lactating dairy cows. Cows were randomized on the farms to receive either a monensin controlled release capsule (CRC) 2 to 4 wk before expected calving or to serve as negative controls. Health data were collected for 90 d postcalving and were analyzed with logistic regression accounting for the intraherd correlation with generalized estimating equations. Monensin CRC significantly reduced the incidence of both clinical ketosis and abomasal displacement post-calving. There was a numerical but nonsignificant decrease in the incidence of retained placenta in cows receiving a monensin CRC. A pooled analysis of two separate but similar studies (conducted in 1995 and 1998) demonstrated a strengthened association between monensin CRC administration precalving and reduced periparturient disease. A 40% reduction in both abomasal displacement and clinical ketosis was observed with precalving administration of a monensin CRC. In addition, the larger dataset highlighted a trend for a 25% reduction in the incidence of retained placenta in monensin-treated cows. Improved energy metabolism as a result of monensin treatment is likely the mechanism for the reduction in incidence of all three of these diseases. Thus the term "energy associated disease" was created to assess the combined impact of the precalving monensin treatment on the incidence of retained placenta, displaced abomasum, and clinical ketosis. The monensin controlled release capsule reduced the incidence of energy associated disease by 30%.


Assuntos
Doenças dos Bovinos/prevenção & controle , Metabolismo Energético/efeitos dos fármacos , Ionóforos/administração & dosagem , Monensin/administração & dosagem , Abomaso/efeitos dos fármacos , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Ionóforos/uso terapêutico , Cetose/epidemiologia , Cetose/prevenção & controle , Cetose/veterinária , Modelos Logísticos , Monensin/uso terapêutico , Placenta Retida/epidemiologia , Placenta Retida/prevenção & controle , Placenta Retida/veterinária , Período Pós-Parto , Gravidez , Distribuição Aleatória , Fatores de Risco , Gastropatias/epidemiologia , Gastropatias/prevenção & controle , Gastropatias/veterinária
19.
J Dairy Sci ; 86(1): 159-68, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12613861

RESUMO

The objective ofthis study was to evaluate the efficacy of intramammary tilmicosin, administered at drying-off, for eliminating Staphylococcus aureus infection, and to identify risk factors for S. aureus cure during the dry period. A total of 219 naturally infected cows, representing 308 quarters, were randomized to receive either one of two treatments at drying-off. Cows received either an intramammary infusion of 500 mg of benzathine cloxacillin, or a sterile solution containing 1,500 mg of tilmicosin. All cows had quarter milk samples taken aseptically three times before dry-off, and at wk 1, 2, and 4 of the subsequent lactation. Overall, 62% of cows and 67.5% of quarters infected with S. aureus cured during the dry period. The cure following administraton of tilmicosin was 67.3 and 72.5% for cows and quarters, respectively. By comparison, the cure achieved with cloxacillin was 56.9 and 62.9% of cows and quarters. Cows receiving tilmicosin were 2.1 times more likely to cure. The cure rate for cows decreased as the linear score on the last DHI test increased, and as the amount of S. aureus being shed increased. Quarters that cultured positive multiple times before drying-off were less likely to cure. Staphylococcus aureus infections located in front quarters of the udder were 2 times more likely to cure than those in hind quarters. Results of this study demonstrate that intramammary tilmicosin at drying-off is efficacious in curing existing S. aureus during the dry period. Risk factors associated with the cure of S. aureus were identified.


Assuntos
Antibacterianos/uso terapêutico , Cloxacilina/análogos & derivados , Macrolídeos , Mastite Bovina/tratamento farmacológico , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Tilosina/análogos & derivados , Tilosina/uso terapêutico , Animais , Antibacterianos/farmacologia , Bovinos , Cloxacilina/farmacologia , Cloxacilina/uso terapêutico , Contagem de Colônia Microbiana/veterinária , Feminino , Lactação , Modelos Logísticos , Glândulas Mamárias Animais/microbiologia , Paridade , Distribuição Aleatória , Fatores de Risco , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Resultado do Tratamento , Tilosina/farmacologia
20.
J Dairy Sci ; 85(12): 3250-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12512598

RESUMO

The objective of this study was to compare the efficacy of an intramammary infusion, containing tilmicosin phosphate, to an infusion of a negative control intramammary placebo for preventing new intramammary infections (IMI) during the dry period. Cows were enrolled from 24 dairy herds from three geographical regions of Canada. Data from 248 cows and 938 bacteriologically negative quarters at drying-off are summarized. Overall, the rate of new IMI during the dry period was 16.7% of quarters. The new infection rates for quarters that received intramammary tilmicosin compared with the intramammary placebo were 14.4 and 19.4%, respectively. The majority of new IMI was caused by coagulase-negative staphylococci (49%) and environmental streptococcal organisms (26.8%). The probability for quarters to develop new IMI in the dry period was significantly increased when cows had higher milk production before drying-off (P = 0.04), when cows had longer dry periods (P = 0.02), and when dry cows were housed in tie-stall barns (P = 0.002). Higher parity cows and those that had a linear score somatic cell count (SCC) above 4 on the last DHI test were also at increased risk for new IMI (P < 0.10). Administration of intramammary tilmicosin appears to be an efficacious therapy for prevention of new IMI; however, there is currently no approved intramammary formulation of this product available. Use of blanket dry cow antibiotic therapy compared to selective dry cow therapy, as well as the importance of identifying risk factors and managing the environment of dry cows are discussed.


Assuntos
Antibacterianos/uso terapêutico , Lactação , Macrolídeos , Glândulas Mamárias Animais/efeitos dos fármacos , Mastite Bovina/prevenção & controle , Tilosina/análogos & derivados , Tilosina/uso terapêutico , Animais , Antibacterianos/administração & dosagem , Canadá , Bovinos , Contagem de Células , Infecções por Escherichia coli/prevenção & controle , Feminino , Infecções por Klebsiella/prevenção & controle , Modelos Logísticos , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/microbiologia , Leite/citologia , Paridade , Placebos , Fatores de Risco , Infecções Estafilocócicas/prevenção & controle , Infecções Estreptocócicas/prevenção & controle , Tilosina/administração & dosagem
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