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1.
J Dairy Sci ; 104(4): 4549-4560, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33663863

RESUMEN

We developed a custom bovine leukemia virus (BLV) control program for the Alberta dairy industry, consisting of a risk assessment and a comprehensive list of best management practices (BMP) aimed at prevention of BLV transmission between cattle. This control program was implemented on 11 farms for approximately 1 yr. Blood samples were collected from all cattle ≥12 mo old, and serum was tested with a commercial ELISA. Risk assessments were performed on each farm, risk-connected on-farm management was identified, and management changes expected to prevent transmission of BLV between cattle were suggested by the first author and agreed upon with each farmer. Throughout the following year, all participating farmers were visited multiple times to identify and overcome barriers to implementation and to monitor progress. After approximately 1 yr of implementing BLV control, all cattle ≥12 mo old on farm with a negative or no previous test result were sampled, and the within-herd prevalence was determined. The median number of cattle on farm that were ≥12 mo was 195 (range 110-524). The initial prevalence averaged 39% (13-66%). On average, 5 BMP (3-7) were suggested to each farmer. On average, 4 BMP (1-7) were implemented. At the second sampling, the average within-herd prevalence of all animals that tested positive (including the previous sampling) was 36% (12-62%). Eight farms reduced their within-herd BLV prevalence, within-herd prevalence stayed constant on 1 farm, and it increased on 1 farm. The remaining farm terminated their participation before the second sampling. The number of seroconversions per farm ranged from 3 to 109, highlighting the success of some producers to minimize new infections. The risk assessment was proven to be a valuable tool to identify flaws in on-farm management, although risk assessment score was unrelated to the within-herd BLV prevalence. Finally, it appeared that implementation of BMP aimed at prevention of BLV transmission between cattle could reduce within-herd BLV prevalence when farmers committed to their implementation.


Asunto(s)
Enfermedades de los Bovinos , Leucosis Bovina Enzoótica , Virus de la Leucemia Bovina , Alberta/epidemiología , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/prevención & control , Industria Lechera , Leucosis Bovina Enzoótica/epidemiología , Leucosis Bovina Enzoótica/prevención & control , Granjas
2.
Animal ; 15(2): 100121, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33712212

RESUMEN

The work presented in this pilot study aimed to identify potential risk factors associated with bovine periodontitis development. Bovine periodontitis is a multifactorial polymicrobial infectious disease for which the aetiopathogenesis and risk factors are not fully understood. From cattle slaughtered in an abattoir in Scotland, 35 dental arcades with periodontal lesions and 40 periodontally healthy arcades were selected over seven visits for study. Multivariable logistic regression analysis was used to evaluate the association between periodontitis and the independent variables, gender, age and breed. For every increase in year of age, cattle were 1.5 times more likely to have periodontitis. A graphical analysis indicated that within the limits of this study, we could not detect any major influence of breed on the age-effect. Although logistic regression analysis demonstrated that periodontitis lesions are more prevalent with increasing age of cattle the underlying mechanisms remain unclear. It is likely that periodontitis is an important cause of oral pain in older cattle and can contribute to reduced productivity/performance. Further studies with a larger sample size are necessary to elucidate the associations between potential risk factors and periodontitis in cattle and to define its effects on animal welfare and productivity.


Asunto(s)
Enfermedades de los Bovinos , Periodontitis , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Periodontitis/epidemiología , Periodontitis/veterinaria , Proyectos Piloto , Factores de Riesgo , Escocia/epidemiología
3.
Rev Bras Parasitol Vet ; 30(1): e020820, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33533797

RESUMEN

Livestock in the Amazon has grown significantly and, although neosporosis in cattle has been reported worldwide, there is no information about N. caninum in production systems in the state of Amazonas. The objective of this study was to determine the prevalence of anti-Neospora caninum antibodies in cattle, their spatial distribution and the risk factors associated with N. caninum infection in the state of Amazonas. Questionnaires were applied to farmers to assess risk factors associated with N. caninum infection. Blood samples were collected from 1,073 animals on 47 farms in 33 municipalities in the four Amazonian subpopulations. IgG anti-N.caninum antibodies were detected by the indirect fluorescence test, with a general prevalence of 30.2%, being seropositive in 43 farms (91.5%), with prevalence ranging from 2.2% to 69.2%. The highest number of high density points was found in subpopulation 3 (municipality of Apuí and other municipalities on the Madeira River and affluent). It was concluded that N. caninum is present with high seroprevalence values, when compared to other cattle producing states in the Amazon region of Brazil. The identified factors can be used as risk indicators so that control measures can be implemented to prevent infection by N. caninum in these herds.


Asunto(s)
Anticuerpos Antiprotozoarios , Enfermedades de los Bovinos , Coccidiosis , Neospora , Animales , Anticuerpos Antiprotozoarios/sangre , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Coccidiosis/diagnóstico , Coccidiosis/epidemiología , Coccidiosis/veterinaria , Factores de Riesgo , Estudios Seroepidemiológicos
4.
Rev Bras Parasitol Vet ; 30(1): e022720, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33533798

RESUMEN

Slaughter condemnations are important sources of information on cattle health. The incidence of bovine parasitic diseases is still very high in Brazil. These diseases, in addition to causing harm to the animals health, are neglected zoonotic diseases in several parts of world. The study analysed not only the Carcass losses, but also the economic damage resulting from slaughter condemnations due to parasitic causes. Cattle slaughter data from the Brazilian Ministry of Agriculture, Livestock and Supply (MAPA), over the period of 2012 to 2015 and data from the Secretary of Livestock and Irrigation of the state of Rio Grande do Sul (SEAPI-RS) were analyzed between 2014 and 2018.The number of organs and carcasses condemned was multiplied by the respective values (in Brazilian Real) obtained from slaughterhouses and subsequently converted into dollars. Brazilian analysis in SIF (Federal Inspection System) establishments showed that more than 1.2 million organs (3,884,505 kg) and 20,000 carcasses (4,547,718 kg) were condemned only due to parasitic causes during post-mortem inspection. In Rio Grande do Sul, in state inspection establishments, more than 1.7 million organs (8,210,559 kg) and 5,000 carcasses (1,243,200 kg) were condemned. These data are alarming and support the need for public policies to control these parasitic diseases.


Asunto(s)
Mataderos , Enfermedades de los Bovinos , Enfermedades Parasitarias en Animales , Mataderos/estadística & datos numéricos , Animales , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/economía , Enfermedades de los Bovinos/epidemiología , Enfermedades Parasitarias en Animales/complicaciones , Enfermedades Parasitarias en Animales/epidemiología , Zoonosis/economía , Zoonosis/epidemiología
5.
J Anim Sci ; 99(1)2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33528019

RESUMEN

Trehalose, a nonreducing disaccharide consisting of d-glucose with α,α-1,1 linkage, was evaluated as a functional material to improve the gut environment in preweaned calves. In experiment 1, 173 calves were divided into two groups; the trehalose group was fed trehalose at 30 g/animal/d with milk replacer during the suckling period, and the control group was fed nonsupplemented milk replacer. Medication frequency was lower in the trehalose group (P < 0.05). In experiment 2, calves (n = 20) were divided into two groups (control group [n = 10] and trehalose group [n = 10]) based on their body weight and reared under the same feeding regimens as in experiment 1. Fresh feces were collected from individual animals at the beginning of the trial (average age 11 d), 3 wk after trehalose feeding (experimental day 22), and 1 d before weaning, and the fecal score was recorded daily. Fecal samples were analyzed for fermentation parameters and microbiota. The fecal score was significantly lower in the trehalose group than in the control group in the early stage (at an age of 14 to 18 d; P < 0.05) of the suckling period. Calves fed trehalose tended to have a higher proportion of fecal butyrate on day 22 than calves in the control group (P = 0.08). Population sizes of Clostridium spp. were significantly lower (P = 0.036), whereas those of Dialister spp. and Eubacterium spp. tended to be higher in the feces of calves in the trehalose group on day 22 (P = 0.060 and P = 0.083). These observations indicate that trehalose feeding modulated the gut environment and partially contributed to the reduction in medication frequency observed in experiment 1.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Diarrea/veterinaria , Heces/microbiología , Microbiota , Leche , Trehalosa/administración & dosificación , Alimentación Animal/análisis , Animales , Peso Corporal , Bovinos , Diarrea/epidemiología , Dieta/veterinaria , Suplementos Dietéticos , Incidencia , Destete
6.
Mem Inst Oswaldo Cruz ; 115: e200521, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33566940

RESUMEN

Outbreaks of a vesiculopustular disease in dairy cattle and milkers have been frequently reported in Brazil since 1999 when the vaccinia virus strain Cantagalo was first isolated in the State of Rio de Janeiro. However, the genomic diversity of the viral isolates associated with these outbreaks is not well known, particularly in the southeastern states that represent the focal point of virus spread to other regions. Here, we report the genomic sequences and an analysis of the polymorphic site profiles and genotypic diversity of four clinical isolates of vaccinia virus strain Cantagalo collected from 1999 to 2006 in southeastern Brazil.


Asunto(s)
Enfermedades de los Bovinos , Virus Vaccinia , Vaccinia , Animales , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Brotes de Enfermedades , Genómica , Filogenia , Vaccinia/epidemiología , Vaccinia/veterinaria , Virus Vaccinia/genética
7.
Rev Bras Parasitol Vet ; 30(1): e023020, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33605388

RESUMEN

Neospora caninum is considered to be one of the main causes of abortion among cattle. The present survey was conducted in the municipality of Rolim de Moura, Rondônia State, Brazil. A questionnaire that investigates the epidemiological aspects of neosporosis was used in the analysis of risk factors associated with the animal-level and herd-level prevalence in dairy cattle. A total of 416 bovine blood samples were collected from 30 farms, and N. caninum antibody levels were measured by Indirect Fluorescent Antibody Test (IFAT). Analysis of dairy cattle serum samples revealed the presence of anti-N. caninum antibodies to be 47.36% (n = 197). Risk factors associated with N. caninum infection were the management system and access locations of dogs. The results of the present survey indicated that infection of dairy cattle with N. caninum is widespread in the studied region of Western Amazon, which has implications for prevention and control of neosporosis in this region. Therefore, integrated control strategies and measures are recommended to prevent and control N. caninum infection in dairy cattle. In addition, direct contact between dairy cattle, dogs and wild animals, which can influence the epidemiology of neosporosis, should be investigated further.


Asunto(s)
Enfermedades de los Bovinos , Coccidiosis , Neospora , Animales , Anticuerpos Antiprotozoarios/sangre , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/transmisión , Coccidiosis/epidemiología , Coccidiosis/prevención & control , Coccidiosis/transmisión , Coccidiosis/veterinaria , Industria Lechera , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Perros , Análisis Factorial , Femenino , Neospora/inmunología , Embarazo , Factores de Riesgo , Estudios Seroepidemiológicos
8.
Exp Appl Acarol ; 83(3): 399-409, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33590359

RESUMEN

Tick infestations and tick-borne diseases are among the leading causes of economic losses in the cattle industry worldwide. Amitraz is one of the most commonly used chemical acaricides against the cattle tick Rhipicephalus (Boophilus) microplus. Resistance to amitraz has been reported in many countries but not in the Philippines. This study aimed to determine whether cattle ticks from provinces in northern and southern Luzon, Philippines, are resistant to amitraz. Engorged or nearly engorged female ticks were collected from 21 farms and allowed to lay eggs to produce larvae. Larval packet test (LPT) was performed using three concentrations of amitraz, as well as a negative control (diluent). Reverse-transcription polymerase chain reaction (RT-PCR) was also performed to amplify a fragment of the octopamine/tyramine receptor gene and was subjected to sequence analysis by multiple nucleotide and amino acid sequence alignments together with reference strain, amitraz-susceptible strain, and amitraz-resistant strain reported in other countries. LPT results suggest the absence of resistance in all of the tested populations. Interestingly, analysis of the octopamine/tyramine receptor amino acid sequence revealed four out of 14 larval pools having substitutions similar to that of the reported amitraz-resistant strains. Although no apparent resistance was observed in this study, prudent use of amitraz should be practiced as the development of resistance is still likely to occur in the future.


Asunto(s)
Acaricidas , Enfermedades de los Bovinos , Rhipicephalus , Infestaciones por Garrapatas , Acaricidas/farmacología , Animales , Bioensayo , Bovinos , Enfermedades de los Bovinos/epidemiología , Femenino , Resistencia a los Insecticidas/genética , Filipinas , Toluidinas
9.
Schweiz Arch Tierheilkd ; 163(2): 139-152, 2021 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-33528364

RESUMEN

INTRODUCTION: Herd medicine is a field of buiatrics characterized by regular and systematic visits by the veterinarian to improve the health and performance of the animals, the quality of animal products and finally the satisfaction of the farm staff. Internationally established key indicators, such as age at first calving, heat recognition rate or the percentage of cows with clinical mastitis per month (%),26 have been available for a long time in the areas of fertility and udder health. These key indicators help veterinarians to recognize and define health problems at herd level at an early stage and to work out measures for their improvement. Such key indicators are currently lacking in the field of claw health, hence making standardized identification of problem farms considerably more difficult. Considering the permanent negative influence of claw health problems on fertility, performance and overall animal welfare, it becomes clear how valuable claw health indicators will be in the future. The aim of this study was, therefore, to develop both primary and secondary indicators of claw health and to define corresponding limit values for Switzerland. Based on a literature search, several primary and secondary indicators were developed (1˚K: Herd problem Yes/No, 2˚K: Classification of the problem). These were discussed in an expert panel consisting of practicing veterinarians, staff of the Swiss bovine herd health service and university professors with regard to their possible practical implementation and relevance. Finally, 3 primary and 10 secondary indicators were judged to be suitable to assess a herd with regard to claw health. The primary key indicators were: proportion of cows leaving the herd due to a claw problem, proportion of lame cows of a herd, and proportion of cattle with at least one claw disease. The corresponding provisional limit values (exceeding the value = problem) for Switzerland were worked out by means of surveys among farmers, hoof trimmers, veterinary students and veterinarians. In addition, recommendations from the literature and current prevalence studies were used to adapt the defined limit values to the situation on Swiss farms. In the coming years, the claw health project «Gesunde Klauen - das Fundament für die Zukunft¼ will collect current prevalence values of claw diseases, and the limit values will then be adjusted and specified accordingly.


Asunto(s)
Enfermedades de los Bovinos/diagnóstico , Industria Lechera/métodos , Enfermedades del Pie/veterinaria , Pezuñas y Garras/patología , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades del Pie/diagnóstico , Enfermedades del Pie/epidemiología , Prevalencia , Suiza
10.
Animal ; 15(3): 100148, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33573952

RESUMEN

The use of anionic salts to prevent milk fever in dairy cattle has been an effective nutritional strategy; however, the degree of acidification that determines the most acceptable productive responses and well-being of the cow is still a controversial topic. The objective of this study was to assess urine pH in prepartum Holstein cows fed anionic diets and determine its association with plasma total Ca, Mg, P, ß-hydroxyl-butyrate (BHB) concentrations at parturition and the occurrence of peripartum disorders. This investigation consisted of 2 studies. Study 1 was conducted on a grazing dairy. Between February and May 2019, 60 prepartum multiparous cows were tested for urine pH and plasma metabolite concentration at parturition. Total Ca, P, Mg and BHB at day 1 in milk (DIM) were assessed and statistically analyzed by ANOVA (models for polynomial regression). Study 2 was conducted on a drylot dairy farm. Between July 2018 and January 2019, 203 cows were evaluated for urine pH and followed-up for 30 DIM to obtain the incidence of dystocia, stillbirths, milk fever, retained fetal membranes, metritis, clinical mastitis and ketosis. Cows were categorized based on their last urine pH as group 1: pH > 7.0 (n = 135); group 2: pH between 6.0 and 7.0 (n = 46) and group 3: pH < 6.0 (n = 22). A logistic regression model for each health event was conducted considering urine pH group as the main effect. Urine sample was collected at 2.71 ±â€¯2.84 days before parturition. In study 1, there was a quadratic effect of urine pH on total Ca. Total Ca concentration was higher between urine pH 6.0 and 7.0, while decreasing below pH 6.0 and above pH 7.0. There was a trend (P = 0.11) for a quadratic effect of urine pH on the concentration of plasma BHB at parturition. ß-Hydroxyl-butyrate was lower approximately between urine pH 6.5 and 7.5. In study 2, the odds for a stillborn in cows with urine pH < 6.0 was 2.39 (95% CI = 1.06-5.40) times the odds for a stillborn in cows with urine pH ≥ 7.0. There was no association between urine pH and the other diseases. In conclusion, cows with prepartum urine pH < 6.0 and >7.0 had lower concentration of plasma total Ca and tended to have a higher concentration of BHB. Cows with urine pH < 6.0 had a higher incidence of stillbirths than cows with urine pH > 7.0.


Asunto(s)
Enfermedades de los Bovinos , Lactancia , Animales , Calcio , Bovinos , Enfermedades de los Bovinos/epidemiología , Dieta , Femenino , Concentración de Iones de Hidrógeno , Leche , Plasma , Periodo Posparto , Embarazo
11.
Trop Anim Health Prod ; 53(1): 62, 2021 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-33389254

RESUMEN

Bovine rotavirus A (RVA) and bovine coronavirus (CoV) are the two main viral enteropathogens associated with neonatal calf diarrhea. The aim of the present work was to study the impact of group and individual housing systems in the epidemiology of RVA and CoV infection. Eleven calves reared in individual housing (FA) and nine calves in group housing (FB) were monitored during the first 7 weeks of life. Stool and serum samples were screened for RVA and CoV antigens by ELISA. IgG1 antibodies (Ab) to both antigens were also measured. From the 160 fecal samples collected, the proportion of positive samples to RVA and CoV was significantly higher in FB (23.6%) than in FA (9%) (p = 0.03). The geometric mean of colostral IgG1 Ab titers to CoV and RVA in FA (IgG1 anti-CoV 1024 and anti-RVA 1782.9) was lower than in FB (IgG1 anti-CoV 10,321.2 and anti-RVA 4096) at birth. Calves less than 2 weeks of life from FB had a higher risk of being infected by RVA (OR = 4.9; p = 0.01) and CoV (OR = 17.15; p = 0.01) than calves from FA. The obtained results showed that there was higher RVA and CoV shedding in group-housed calves than in individual-housed animals.


Asunto(s)
Enfermedades de los Bovinos/virología , Infecciones por Coronavirus/veterinaria , Vivienda para Animales , Infecciones por Rotavirus/veterinaria , Animales , Animales Recién Nacidos , Argentina , Bovinos , Enfermedades de los Bovinos/epidemiología , Calostro/inmunología , Infecciones por Coronavirus/virología , Coronavirus Bovino , Industria Lechera , Diarrea/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Heces/virología , Femenino , Inmunoglobulina G/inmunología , Estudios Longitudinales , Embarazo , Rotavirus , Infecciones por Rotavirus/virología , Esparcimiento de Virus
12.
Trop Anim Health Prod ; 53(1): 76, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33404940

RESUMEN

The aim of the present study was to evaluate the spatial distribution of the prevalence of T. gondii in cows using the indirect immunofluorescence assay and determine associated risk factors. Serum samples were collected from 2970 cows on 263 rural farms in 223 municipalities. A questionnaire was administered to herd owners to collect data for the evaluation of risk factors associated with this disease. Mean seroprevalence of T. gondii in cows was 8.48% (95% CI: 7.48 to 9.49). The microregions with the greatest likelihood (p ≤ 0.05) of having infected animals were Anápolis, Ceres, São Miguel do Araguaia, the Federal District, Anicuns, and Vão do Paraná. The purchase of females or males for reproductive/breeding purposes was significantly associated (p ≤ 0.05) with the prevalence of T. gondii in these regions. A positive correlation (0.7618; p = 0.047) was found between the prevalence of T. gondii and total area in hectares of forests in these regions, suggesting that wild cats may be disseminating T. gondii at these sites. The present results highlight the importance of considering the meat from these animals to be an important infection route for humans who eat raw or undercooked food.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Toxoplasma/aislamiento & purificación , Toxoplasmosis Animal/epidemiología , Animales , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/parasitología , Femenino , Técnica del Anticuerpo Fluorescente Indirecta/veterinaria , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos , Toxoplasmosis Animal/parasitología
13.
Trop Anim Health Prod ; 53(1): 92, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33415465

RESUMEN

West Nile fever (WNF) and Rift Valley fever (RVF) are emerging and re-emerging zoonotic diseases of veterinary and public health importance in Africa. Despite the existence of potential vectors and a wide range of hosts, the transmission of these diseases in domestic animals has not been well documented in the South Omo area of Ethiopia. This study aimed to estimate the sero-prevalence of IgG antibodies produced against West Nile virus (WNV) and Rift Valley fever virus (RVFV) infections among cattle in the South Omo area. Between May and June 2019, blood samples were collected from 397 cattle and screened for IgG antibodies against WNV and RVFV infections using enzyme-linked immunosorbent assay (ELISA). The overall sero-prevalence of IgG antibody to WNV infection was 4.8% (95% CI: 2.67-6.88%), while it was 5.0% to RVFV infection (95% CI: 2.87-7.18). Compared to 1-3 years old cattle, those in the age group ≥ 7 years had significantly higher odds of being positive for WNV (AOR = 6.82; 95% CI: 1.72-26.99) and RVFV (AOR = 4.38; 95% CI: 1.08-17.88) infections. The occurrence of WNV and RVFV infections in cattle population in the present study area indicates the risk of transmission to humans. Strengthening the surveillance system and conducting further studies to identify active cases in domestic and wild animals as well as in humans is crucial to reduce the risk of possible outbreaks.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Fiebre del Valle del Rift/epidemiología , Virus de la Fiebre del Valle del Rift/fisiología , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/fisiología , Crianza de Animales Domésticos , Animales , Bovinos , Enfermedades de los Bovinos/virología , Etiopía/epidemiología , Prevalencia , Fiebre del Valle del Rift/virología , Estudios Seroepidemiológicos , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/virología
14.
J Dairy Sci ; 104(3): 3123-3143, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33455766

RESUMEN

Johne's disease (JD), or paratuberculosis, is an infectious inflammatory disorder of the intestines primarily associated with domestic and wild ruminants including dairy cattle. The disease, caused by an infection with Mycobacterium avium subspecies paratuberculosis (MAP) bacteria, burdens both animals and producers through reduced milk production, premature culling, and reduced salvage values among MAP-infected animals. The economic losses associated with these burdens have been measured before, but not across a comprehensive selection of major dairy-producing regions within a single methodological framework. This study uses a Markov chain Monte Carlo approach to estimate the annual losses per cow within MAP-infected herds and the total regional losses due to JD by simulating the spread and economic impact of the disease with region-specific economic variables. It was estimated that approximately 1% of gross milk revenue, equivalent to US$33 per cow, is lost annually in MAP-infected dairy herds, with those losses primarily driven by reduced production and being higher in regions characterized by above-average farm-gate milk prices and production per cow. An estimated US$198 million is lost due to JD in dairy cattle in the United States annually, US$75 million in Germany, US$56 million in France, US$54 million in New Zealand, and between US$17 million and US$28 million in Canada, one of the smallest dairy-producing regions modeled.


Asunto(s)
Enfermedades de los Bovinos , Paratuberculosis , Animales , Canadá , Bovinos , Enfermedades de los Bovinos/epidemiología , Industria Lechera , Femenino , Francia , Alemania , Nueva Zelanda , Estados Unidos
15.
J Dairy Sci ; 104(4): 4575-4583, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33516551

RESUMEN

The objective of this study was to identify changes in prepartum behavior associated with the incidence of postpartum diseases in dairy cows. Multiparous Holstein cows (n = 489) were monitored with accelerometers for 3 wk prepartum. Accelerometers measured steps, time at the feed bunk, frequency of meals, lying bouts, and lying time. Postpartum health was monitored from 0 to 30 d in milk and cases of metritis, mastitis, retained placenta, displaced abomasum (DA), ketosis, and hypocalcemia were recorded. A multivariate linear mixed model was used to assess differences in behavior between diseased and not diagnosed diseased cows. A multivariate logistic regression was used to predict the occurrence of diseases. Predictors were selected using a manual backward stepwise selection process of variables until all remaining predictors had a P < 0.10. Models were submitted to a leave-one-out cross-validation process, and sensitivity, specificity, false discovery rate, and false omission rate were calculated. On average, over the 3-wk prepartum period, cows not diagnosed diseased (n = 345) took 1,613 ± 38 steps, spent 181 ± 7.1 min at the feed bunk, had 8.3 ± 0.17 meals, had 9.8 ± 0.32 lying bouts, and spent 742 ± 11.3 min lying per day. Behavior of diseased cows (n = 144) did not differ from those not diagnosed diseased. However, differences for specific diseases were observed, being significant in the week prepartum. When considering changes in behavior for only the week before calving, cows with metritis had more lying bouts (+21%), cows with DA had fewer meals (-24%) and tended to take fewer steps (-18%), and cows with ketosis had fewer meals (-22%) and spent less time at the feed bunk (-40%). Prediction models with the best outcomes were found for DA and ketosis using data of the prepartum week only. The model for DA included time at the feed bunk. Cross-validation resulted in a 80% sensitivity, 58.1% specificity, 59.2% accuracy, 91.2% false discovery rate, and 1.7% false omission rate. The model for ketosis included time at the feed bunk and number of meals. Cross-validation resulted in 64.3% sensitivity, 59.3% specificity, 59.5% accuracy, 93.0% false discovery rate, and 2.8% false omission rate. Prepartum behavior of cows affected with metritis, DA, and ketosis was different from that of cows not diagnosed with diseases. Prediction equations were able to classify cows at high or low risk of ketosis and DA and can be used in taking management decisions, but the high false discovery rates requires further refinement.


Asunto(s)
Enfermedades de los Bovinos , Cetosis , Trastornos Puerperales , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Femenino , Cetosis/epidemiología , Cetosis/veterinaria , Lactancia , Periodo Posparto , Embarazo , Trastornos Puerperales/veterinaria
16.
Animal ; 15(1): 100017, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33515993

RESUMEN

Hypocalcaemia is a common metabolic disorder of post-parturient dairy cows; enhancement of our knowledge regarding Ca dynamics would improve cow health and welfare. This study investigated the presence of time- and severity-related subclinical hypocalcaemia (SCHCa) patterns in Holstein cows after calving and their association with diseases during the first week of lactation. A total of 938 cows from nine herds were blood sampled on days 1, 2, 4 and 8 post-partum, and serum Ca concentration was measured with atomic absorption. Subclinical ketosis (serum ß-hydroxybutyrate≥1.2 mmol/L) and cases of retained foetal membranes, metritis (MET), mastitis, ketosis and displaced abomasum (DA) were recorded. Using receiver operating characteristic (ROC) analysis, the SCHCa cut-off was identified at serum Ca ≤ 2.09 mmol/L. Hierarchical and two-step cluster analysis classified cows to seven clusters based on test day cow Ca records and overall SCHCa status. Two clusters (NORM and HIGH) included 318 normocalcaemic cows and five clusters (SCH-1 to -5) those that were at least once subclinically hypocalcaemic (n = 620). A second ROC analysis was performed in order to distinguish mild from severe cases of SCHCa in these 620 cows; this cut-off was identified at 1.93 mmol/L. The associated risk of disease with Ca clustership was assessed with generalized linear mixed models. Overall incidence of SCHCa was 66.1%. Clusters SCH-1 and SCH-2 included cows with short-term SCHCa of day 1 and day 2, respectively, while SCH-3 included cows with severe and prolonged SCHCa extending to day 4 and beyond. Clusters SCH-4 and SCH-5 included cows with delayed SCHCa, which culminated on days 4 and 8, respectively. Compared to NORM cows in HIGH had lower risk of MET and no cases of DA. Cows in SCH-3 had higher risk of being diagnosed with retained foetal membranes, DA or any disease during the study period. Cows in SCH-5 had higher risk of being diagnosed with ketosis, subclinical ketosis or any disease. In conclusion, there are multiple normocalcaemic and hypocalcaemic patterns that are differently associated with disease risk.


Asunto(s)
Enfermedades de los Bovinos , Hipocalcemia , Cetosis , Ácido 3-Hidroxibutírico , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Femenino , Hipocalcemia/diagnóstico , Hipocalcemia/veterinaria , Cetosis/diagnóstico , Cetosis/veterinaria , Lactancia , Periodo Posparto , Embarazo
17.
J Dairy Sci ; 104(2): 2151-2163, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33309376

RESUMEN

The objective of this prospective cohort study was to investigate the effect of bovine coronavirus (BCoV), bovine rotavirus (BRoV), and Cryptosporidiumparvum on dairy calf health and performance and to determine the prevalence of these pathogens. A total of 198 male dairy calves housed at a grain-fed veal facility were examined from June 11, 2018, to October 9, 2018. Calves were fed milk replacer twice daily and housed individually until weaning at 56 d. Once weaned, calves were moved into groups of 5 until they were moved to a finishing facility at 77 d. At the grain-fed veal facility, calves were scored for fecal consistency for the first 28 d and had fecal samples taken on arrival and at 7 and 14 d. Fecal samples were frozen and submitted to a commercial laboratory, where they were tested for BCoV, C.parvum, and 2 groups of BRoV: group A (BRoV A) and group B (BRoV B). Calves were weighed on arrival and at 14, 49, 56, and 77 d using a digital body scale. Treatments for disease and mortalities that occurred over the 77 d were also recorded. Statistical models, including Cox proportional hazards and repeated measures models, were built to determine the effect of infection with 1 of the pathogens. Over the 3 sampling points, 151 (85.8%), 178 (94.2%), 3 (1.5%), and 97 (57.4%) calves tested positive at least once for BCoV, BRoV A, BRoV B, and C.parvum, respectively. The source of the calves and the level of serum total protein measured on arrival were associated with testing positive for a pathogen. Calves that tested positive for C.parvum had an increased proportion of days with diarrhea and severe diarrhea; calves that tested positive for BCoV and BRoV A had an increased proportion of days with severe diarrhea. In addition, calves that tested positive for C.parvum had a higher hazard of being treated for respiratory disease. With respect to body weight, calves that had diarrhea or severe diarrhea had lower body weight at 49, 56, and 77 d. Specifically, calves that had an increased proportion of days with diarrhea showed a reduction in weight gain of up to 15 kg compared to calves without diarrhea. Calves that tested positive for C.parvum had a lower body weight at 49, 56, and 77 d; calves that tested positive for BCoV had a lower body weight at 56 and 77 d. This study demonstrates that the prevalence of BCoV, BRoV A, and C.parvum infection is high in this population of calves and has significant effects on the occurrence of diarrhea and body weight gain. Future studies should evaluate approaches for minimizing the effect of infection with these pathogens to improve the welfare, health, and productivity of dairy calves.


Asunto(s)
Enfermedades de los Bovinos/fisiopatología , Infecciones por Coronavirus/veterinaria , Coronavirus Bovino , Criptosporidiosis/fisiopatología , Cryptosporidium parvum , Infecciones por Rotavirus/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/virología , Estudios de Cohortes , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/fisiopatología , Criptosporidiosis/parasitología , Diarrea/parasitología , Diarrea/veterinaria , Diarrea/virología , Heces/química , Heces/parasitología , Heces/virología , Masculino , Prevalencia , Estudios Prospectivos , Enfermedades Respiratorias/terapia , Enfermedades Respiratorias/veterinaria , Rotavirus , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/fisiopatología , Aumento de Peso
18.
J Dairy Sci ; 104(2): 2231-2242, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33309370

RESUMEN

The objective of this study was to investigate associations of freestall design and cleanliness with cow lying behavior, hygiene, lameness, and risk of new high somatic cell count (SCC). Cows from 18 commercial freestall dairy herds (22 ± 15 cows/farm; mean ± SD) in Ontario, Canada, were enrolled in a longitudinal study. Four hundred focal cows that were <120 d in milk, had no mastitis treatment in the last 3 mo, and had an SCC <100,000 cells/mL at their most recent milk test were selected for the study. Data on SCC were collected through Dairy Herd Improvement Association milk testing (at ~5-wk intervals). Each farm was visited 5 ± 3 d (mean ± SD) after each milk test until 3 tests were completed (~105 d), for a total of 3 observation periods per cow. Elevated SCC was used as an indicator of subclinical mastitis. An incident of new high SCC was defined as a cow having SCC >200,000 cells/mL at the end of an observation period, when SCC was <100,000 cells/mL at the beginning of that period. Lying behavior was recorded for 6 d after each milk sampling, using electronic data loggers. Cows were scored during each period for lameness (5-point scale, with scores ≥3 = lame), body condition score (BCS; 5-point scale; 1 = thin to 5 = fat), and hygiene (4-point scale). Stall cleanliness was assessed during each period with a 1.20 × 1.65-m metal grid, containing 88 squares. The grid was centered between stall partitions of every tenth stall on each farm, and the squares containing visible urine or fecal matter (or both) were counted. Cow lying time averaged 10.9 ± 1.9 h/d. On average, cows with low BCS (≤2.5) spent 37 ± 16.6 min/d less time lying down than high-BCS cows (≥4.0). On average, cows tended to spend 36 ± 18.3 min/d more time lying down in deep-bedded versus mattress-based stalls. Mean proportion of soiled squares per stall was 20.1 ± 0.50%. Across farms, cow lying time decreased as the proportion of soiled squares per stall increased. A difference in daily lying time of ~80 more min/d was modeled for cows housed in barns with the cleanest stalls compared with those with the dirtiest stalls. Higher neck rail height [for every 1 SD (10 cm) increase] increased the odds (odds ratio = 1.5) of cows having a dirty upper leg-flank and udder. The odds of a cow having a dirty upper leg-flank, udder, and lower legs were 1.5, 2.0, and 1.9 times greater, respectively, for cows housed with dirtier stalls. Also, cows housed on farms with dirtier stalls had 1.3 times greater odds of being lame at the time of observation. Over the study period, 50 new high-SCC cases were detected, resulting in an incidence rate of 0.45 cases of new high SCC per cow-year at risk. No measured factors were detected to be associated with risk of a new high SCC. Overall, our results confirm that cows lie down longer in cleaner and more comfortable environments. Further, these results highlight the need for improved stall cleanliness to optimize lying time and potentially reduce lameness.


Asunto(s)
Conducta Animal , Enfermedades de los Bovinos/prevención & control , Bovinos , Industria Lechera/métodos , Vivienda para Animales , Leche/citología , Animales , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/etiología , Recuento de Células/veterinaria , Femenino , Higiene , Cojera Animal/epidemiología , Cojera Animal/etiología , Cojera Animal/prevención & control , Estudios Longitudinales , Mastitis Bovina/etiología , Mastitis Bovina/prevención & control , Ontario/epidemiología , Postura
19.
J Dairy Sci ; 104(2): 2369-2383, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33309353

RESUMEN

The objective of the current study was to evaluate the relationship of body condition score (BCS) at 35 d in milk (DIM), milk production, diseases, and duration of the dry period with prevalence of anovulation at 49 DIM and then, specifically, with the prevalence of each anovular phenotype. We hypothesized that anovular follicular phenotypes, classified based on maximal size of the anovular follicle, have different etiologies. A total of 942 lactating Holstein cows (357 primiparous and 585 multiparous) from 1 herd had ovaries evaluated by ultrasonography at 35 ± 3 and 49 ± 3 DIM to detect the absence of a corpus luteum (CL), and to measure the diameter of the largest follicle. Cows were classified as cyclic at 49 DIM if a CL was observed in at least 1 of the 2 examinations, or anovular if no CL was observed at either examination. Cows considered anovular were divided into 3 groups based on the largest diameter of the largest follicle as follows: ranging from 8 to 13 mm, 14 to 17 mm, or ≥18 mm. Cows were evaluated for the following diseases: retained placenta, metritis, hyperketonemia, mastitis, lameness, respiratory problem, and digestive problem. At 35 DIM, BCS was determined, and milk yield for individual cows was recorded. A total of 28.5% (268/942) of cows were classified as anovular. Anovular cows had longer dry periods (90 vs. 71 d) and smaller BCS than cyclic cows (2.83 vs. 2.99). Cows with a single disease or multiple diseases had 2 and 3-fold increase in odds of being anovular, respectively. Anovular cows had follicles that ranged from 4 to 50 mm. The prevalence of anovular phenotype, among anovular cows, that had the diameter of the largest follicle ranging from 8 to 13 mm, 14 to 17 mm, and ≥18 mm was 29.9 (79/264), 37.5 (99/264), and 32.6% (86/264), respectively. Anovular cows with follicles of 8 to 13 mm had longer dry periods than those with follicles ≥18 mm (104 vs. 74 d), whereas anovular cows with medium size follicles had intermediate days dry (99 d). Cows with small and medium anovular follicles had smaller BCS and greater prevalence of multiple diseases than cyclic cows. For almost all risk factors, the cows with large anovular follicles (≥18 mm) were similar to cyclic cows and different from cows with smaller anovular follicles (8-13 mm). Thus, longer dry periods, less BCS at 35 DIM, and diseases were risk factors for anovulation. Moreover, the risk factors for the 3 distinct anovular follicle phenotypes differed.


Asunto(s)
Anovulación/veterinaria , Enfermedades de los Bovinos/epidemiología , Animales , Anovulación/epidemiología , Anovulación/etiología , Bovinos , Enfermedades de los Bovinos/etiología , Cuerpo Lúteo/anomalías , Femenino , Lactancia , Leche , Folículo Ovárico , Fenotipo , Embarazo , Prevalencia , Factores de Riesgo
20.
J Parasitol ; 106(6): 772-788, 2020 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-33326588

RESUMEN

Toxoplasma gondii infections are common in humans and animals worldwide. The ingestion of food or water contaminated with oocysts excreted by infected cats or ingesting uncooked or undercooked meat containing tissue cysts of T. gondii are the 2 major modes of transmission of T. gondii. Viable T. gondii is more prevalent in pork and lamb than in beef. In the past decade, there have been many articles on the high seroprevalence in cattle, particularly from China. There is a report of an outbreak of acute toxoplasmosis in humans suspected to be linked to the ingestion of Artisan fresh cheese from cow's milk. There are conflicting reports concerning the rate of congenital transmission of T. gondii in cattle, especially from Brazil. In a report from Brazil, viable T. gondii was isolated from the blood of 1 of 60 pregnant cows slaughtered at an abattoir and from 1 fetus. The role of beef in the epidemiology of T. gondii infections is still not clear. Here, we review prevalence, persistence of infection, clinical disease, epidemiology, and public health risks of T. gondii infections in cattle from beef and cow's milk worldwide for the past decade.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Salud Pública , Toxoplasmosis Animal/parasitología , Animales , Anticuerpos Antiprotozoarios/sangre , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/transmisión , Variación Genética , Genotipo , Salud Global , Humanos , Carne/parasitología , Leche/parasitología , Estudios Seroepidemiológicos , Toxoplasma/clasificación , Toxoplasma/genética , Toxoplasma/inmunología , Toxoplasmosis Animal/diagnóstico , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/transmisión , Toxoplasmosis Congénita/transmisión
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