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1.
Animal ; 15(2): 100121, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33712212

RESUMO

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.


Assuntos
Doenças dos Bovinos , Periodontite , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Periodontite/epidemiologia , Periodontite/veterinária , Projetos Piloto , Fatores de Risco , Escócia/epidemiologia
2.
Animal ; 15(2): 100126, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33712215

RESUMO

Liver flukes (Fasciola spp.) are important helminth parasites of livestock globally and cause substantial reductions in health and productivity of beef cattle. Attempts to control fluke have been thwarted by the difficulty of vaccine design, the evolution of flukicide resistance and the need to control the intermediate snail host. Mechanisms to reduce the impact of parasites on animal performance have typically focused on promoting host resistance - defined as the ability of the host to kill and remove the parasite from its system - and such strategies include improving protein nutrition or selective breeding for resistance. Organisms, however, have another broad mechanism for mitigating the impact of parasites: they can show tolerance, defined as the ability to maintain health or performance under increasing parasite burden. Tolerance has been studied in the plant literature for over a century, but there are very few empirical studies of parasite tolerance in livestock. In this study, we used data collected from >90 000 beef cattle to estimate the impact of the severity of liver fluke infection on performance and variation in tolerance of fluke. Severity of liver fluke infection was estimated using liver "fibrosis score" on a scale of 0-3 and performance estimated as (1) age at slaughter and (2) daily dead weight gain. Animals with higher fibrosis scores were slaughtered around 2 weeks later than animals with no fluke and gained around 10 g less weight per day. There was also considerable variation in these effects of fibrosis score, such that animals from different producers and breeds varied in their tolerance of fluke infection. While breeds did not vary in the association between fibrosis and age at slaughter, there was considerable variation among producers: high fibrosis score delayed slaughter by up to 50 days in some producers, but not at all in others. Meanwhile, there was support for variation in the slope of daily dead weight gain on fibrosis score among both breeds and producers, with some unaffected by high fluke scores and some breeds and producers experiencing a 20 g/day lower weight gain under high fluke scores. Our results point to the potential for both environmental and genetic variation in tolerance of liver fluke in cattle, paving the way for quantitative genetic and nutritional research into the feasibility of promoting tolerance as a disease mitigation strategy.


Assuntos
Doenças dos Bovinos , Fasciola hepatica , Fasciolíase , Animais , Peso Corporal , Bovinos , Fasciolíase/veterinária , Ganho de Peso
3.
Sensors (Basel) ; 21(4)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671216

RESUMO

The prediction of health disorders is the goal of many sensor systems in dairy farming. Although mastitis and lameness are the most common health disorders in dairy cows, these diseases or treatments are a rare event related to a single day and cow. A number of studies already developed and evaluated models for classifying cows in need of treatment for mastitis and lameness with machine learning methods, but few have illustrated the effects of the positive predictive value (PPV) on practical application. The objective of this study was to investigate the importance of low-frequency treatments of mastitis or lameness for the applicability of these classification models in practice. Data from three German dairy farms contained animal individual sensor data (milkings, activity, feed intake) and were classified using machine learning models developed in a previous study. Subsequently, different risk criteria (previous treatments, information from milk recording, early lactation) were designed to isolate high-risk groups. Restricting selection to cows with previous mastitis or hoof treatment achieved the highest increase in PPV from 0.07 to 0.20 and 0.15, respectively. However, the known low daily risk of a treatment per cow remains the critical factor that prevents the reduction of daily false-positive alarms to a satisfactory level. Sensor systems should be seen as additional decision-support aid to the farmers' expert knowledge.


Assuntos
Criação de Animais Domésticos/instrumentação , Doenças dos Bovinos/diagnóstico , Indústria de Laticínios , Coxeadura Animal/diagnóstico , Mastite/diagnóstico , Animais , Bovinos , Fazendas , Feminino , Lactação , Leite
4.
Methods Mol Biol ; 2291: 19-86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704748

RESUMO

Cattle and other ruminants are primary reservoirs for Shiga toxin-producing Escherichia coli (STEC) strains which have a highly variable, but unpredictable, pathogenic potential for humans. Domestic swine can carry and shed STEC, but only STEC strains producing the Shiga toxin (Stx) 2e variant and causing edema disease in piglets are considered pathogens of veterinary medical interest. In this chapter, we present general diagnostic workflows for sampling livestock animals to assess STEC prevalence, magnitude, and duration of host colonization. This is followed by detailed method protocols for STEC detection and typing at genetic and phenotypic levels to assess the relative virulence exerted by the strains.


Assuntos
Doenças dos Bovinos , Infecções por Escherichia coli , Toxina Shiga II/metabolismo , Escherichia coli Shiga Toxigênica , Doenças dos Suínos , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/metabolismo , Escherichia coli Shiga Toxigênica/patogenicidade , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/metabolismo , Doenças dos Suínos/microbiologia
5.
Schweiz Arch Tierheilkd ; 163(3): 239-244, 2021 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-33650524

RESUMO

INTRODUCTION: Renal cysts are fluid-filled cavities with an epithelial lining that, depending on their size, can cause clinical symptoms and thus require conservative or surgical therapy. Nephrectomy is primarily used in cattle for simple kidney cysts while sclerotherapy is well established in humans and individual case reports have been published in small animal medicine. This case report describes the first successful treatment of a solitary, perirenal cyst using a right-sided laparotomy and intraluminal instillation of 96% ethanol solution in a Swiss Fleckvieh cow. Diagnostics, surgical procedures and aftercare are descripted and risks are compared to other methods. Sclerotherapy is an organ-preserving alternative to nephrectomy that is suitable for buiatric practice, the methodology should be confirmed in subsequent intervention studies.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/cirurgia , Etanol/administração & dosagem , Doenças Renais Císticas/veterinária , Laparotomia/veterinária , Escleroterapia/veterinária , Animais , Bovinos , Feminino , Doenças Renais Císticas/tratamento farmacológico , Doenças Renais Císticas/cirurgia , Escleroterapia/normas , Suíça , Resultado do Tratamento
6.
Schweiz Arch Tierheilkd ; 163(2): 139-152, 2021 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-33528364

RESUMO

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.


Assuntos
Doenças dos Bovinos/diagnóstico , Indústria de Laticínios/métodos , Doenças do Pé/veterinária , Casco e Garras/patologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças do Pé/diagnóstico , Doenças do Pé/epidemiologia , Prevalência , Suíça
7.
Animal ; 15(2): 100124, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33573946

RESUMO

Enterotoxigenic Escherichia coli (ETEC) K99 is one of the major pathogens associated with calf diarrhea. The induction of passive immunity in animals by immunoglobulin Y and using probiotics are inexpensive alternatives to antibiotics for the prevention and treatment of a number of bacterial infections, including diarrhea. Hence, the aim of this research was to evaluate the impact of dietary probiotics and ETEC K99-specific egg yolk antibody supplements, alone and in combination with each other, on health and growth parameters, diarrhea incidence and immune stimulation in newborn Holstein calves. One hundred and twenty neonatal calves were allocated randomly into 4 dietary groups (n = 30 per group) received colostrum/milk without any additives (control group), or supplemented with egg yolk powder contained E. coli K99-specific antibody (Ab group; 1 g/day), a commercial probiotic, Hypro-calves (Pro group; 3 g/day), and their combination (Ab+Pro group), from day (d) 1 to d28 of age. Analyses of the growth parameters, feed efficiency, fecal score, and microbiota and immune function were carried out on d0, 14, 21, and 28 of the experiment. Calves in Ab or Ab+Pro group had higher (P < 0.05) average daily gain compared to control and Pro groups during 0-14d. Feed efficiency of calves in Ab and Ab+Pro groups was significantly higher than that in control group during the period of 0-14d; however, no significant differences were observed in 0-28d period. Diarrhea prevalence and fecal score in Ab+Pro group were lower than control group (P < 0.05). Calves in Ab+Pro group had the lowest number of fecal E. coli in comparison to other groups on d28 (P < 0.05). Feeding Ab+Pro supplement increased (P < 0.05) concentrations of blood IgA and serum CD4 compared to the control group. Likewise, calves in Pro group had higher CD4 levels as compared to the control calves (P < 0.05). Serum concentration of interferon-gamma in control group was lower than other groups (P < 0.05). Overall, these data suggest that feeding a combination of probiotic and specific antibody against ETEC to neonate Holstein calves enhances feed efficiency, boosts immunity, and reduces diarrhea prevalence.


Assuntos
Doenças dos Bovinos , Probióticos , Animais , Animais Recém-Nascidos , Bovinos , Diarreia/prevenção & controle , Diarreia/veterinária , Feminino , Sistema Imunitário , Imunoglobulinas , Incidência , Óvulo , Gravidez
8.
Animal ; 15(2): 100093, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518489

RESUMO

Technological progress enables individual cow's temperatures to be measured in real time, using a bolus sensor inserted into the rumen (reticulorumen). However, current cooling systems often work at a constant schedule based on the ambient temperature and not on monitoring the animal itself. This study hypothesized that tailoring the cooling management to the cow's thermal reaction can mitigate heat stress. We propose a dynamic cooling system based on in vivo temperature sensors (boluses). Thus, cooling can be activated as needed and is thus most efficacious. A total of 30 lactating cows were randomly assigned to one of two groups; the groups received two different evaporative cooling regimes. A control group received cooling sessions on a preset time-based schedule, the method commonly used in farms; and an experimental group, which received the sensor-based (SB) cooling regime. Sensor-based was changed weekly according to the cow's reaction, as reflected in the changes in body temperatures from the previous week, as measured by reticulorumen boluses. The two treatment groups of cows had similar milk yields (44.7 kg/d), but those in the experimental group had higher milk fat (3.65 vs 3.43%), higher milk protein (3.23 vs 3.13%), higher energy corrected milk (ECM, 42.84 vs 41.48 kg/d), higher fat corrected milk 4%; (42.76 vs 41.34 kg/d), and shorter heat stress duration (5.03 vs 9.46 h/day) comparing to the control. Dry matter intake was higher in the experimental group. Daily visits to the feed trough were less frequent, with each visit lasting longer. The sensor-based cooling regime may be an effective tool to detect and ease heat stress in high-producing dairy cows during transitional seasons when heat load can become severe in arid and semi-arid zones.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Temperatura Baixa , Feminino , Transtornos de Estresse por Calor/prevenção & controle , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Temperatura Alta , Lactação , Leite
9.
Exp Appl Acarol ; 83(3): 399-409, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33590359

RESUMO

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.


Assuntos
Acaricidas , Doenças dos Bovinos , Rhipicephalus , Infestações por Carrapato , Acaricidas/farmacologia , Animais , Bioensaio , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Resistência a Inseticidas/genética , Filipinas , Toluidinas
10.
J Anim Sci ; 99(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33528019

RESUMO

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.


Assuntos
Doenças dos Bovinos/epidemiologia , Diarreia/veterinária , Fezes/microbiologia , Microbiota , Leite , Trealose/administração & dosagem , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Diarreia/epidemiologia , Dieta/veterinária , Suplementos Nutricionais , Incidência , Desmame
11.
Rev Bras Parasitol Vet ; 30(1): e020820, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533797

RESUMO

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.


Assuntos
Anticorpos Antiprotozoários , Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Coccidiose/veterinária , Fatores de Risco , Estudos Soroepidemiológicos
12.
Rev Bras Parasitol Vet ; 30(1): e022720, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533798

RESUMO

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.


Assuntos
Matadouros , Doenças dos Bovinos , Doenças Parasitárias em Animais , Matadouros/estatística & dados numéricos , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/economia , Doenças dos Bovinos/epidemiologia , Doenças Parasitárias em Animais/complicações , Doenças Parasitárias em Animais/epidemiologia , Zoonoses/economia , Zoonoses/epidemiologia
13.
Mem Inst Oswaldo Cruz ; 115: e200521, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33566940

RESUMO

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.


Assuntos
Doenças dos Bovinos , Vírus Vaccinia , Vaccinia , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Surtos de Doenças , Genômica , Filogenia , Vaccinia/epidemiologia , Vaccinia/veterinária , Vírus Vaccinia/genética
14.
Rev Bras Parasitol Vet ; 30(1): e023020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605388

RESUMO

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.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/transmissão , Coccidiose/epidemiologia , Coccidiose/prevenção & controle , Coccidiose/transmissão , Coccidiose/veterinária , Indústria de Laticínios , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Análise Fatorial , Feminino , Neospora/imunologia , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
15.
Rev Bras Parasitol Vet ; 30(1): e025220, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605390

RESUMO

Southern cattle tick resistance to pour-on and injectable acaricides has yet to be evaluated on a broader scope, and the paucity of information on the subject may hinder efforts to control this parasite. The objective of this study was to evaluate the resistance profile of ten populations of Rhipicephalus microplus to the acaricides fluazuron, fipronil and ivermectin in cattle herds in Mato Grosso do Sul, Brazil. The larval immersion test (LIT) was used to evaluate susceptibility to ivermectin and fipronil and the adult immersion test (AIT) was performed to evaluate fluazuron. Samples were randomly obtained in ten farms, and in general, we found resistance in five samples to fluazuron and in four samples to ivermectin and fipronil. Six samples showed incipient resistance to ivermectin and fipronil. Five of the ten evaluated samples showed resistance and/or incipient resistance to all the active ingredients, and the other five to two active ingredients. Among the samples classified as resistant, the average resistance ratio for ivermectin was 2.75 and 3.26 for fipronil. These results demonstrate the advanced status of resistance to the most modern chemical groups for the control of R. microplus in the state of Mato Grosso do Sul.


Assuntos
Acaricidas , Doenças dos Bovinos , Resistência a Medicamentos , Rhipicephalus , Infestações por Carrapato , Acaricidas/farmacologia , Animais , Brasil , Bovinos , Doenças dos Bovinos/parasitologia , Ivermectina/farmacologia , Compostos de Fenilureia/farmacologia , Pirazóis/farmacologia , Rhipicephalus/efeitos dos fármacos , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária
16.
Animal ; 15(3): 100148, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33573952

RESUMO

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.


Assuntos
Doenças dos Bovinos , Lactação , Animais , Cálcio , Bovinos , Doenças dos Bovinos/epidemiologia , Dieta , Feminino , Concentração de Íons de Hidrogênio , Leite , Plasma , Período Pós-Parto , Gravidez
17.
Trop Anim Health Prod ; 53(1): 66, 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33392887

RESUMO

The decline of milk production in crossbred cattle during the onset of summer was evaluated using lactation records of the cows (n = 48) maintained at the Livestock Research Station, Thiruvazhamkunnu, for the period between January 2019 and March 2019. Climate data were obtained from an automatic weather station maintained on the campus. The temperature-humidity index (THI) was used to assess the thermal stress on animals. Values varied between 70.78 and 83.93 during the study period, indicating that the cows were exposed to mild and moderate stress. Highly significant negative correlations (p < 0.01) were observed between the average temperature, THI, and milk production. Linear, logarithmic, power, and polynomial models linking milk production and THI were used to fit the data. The coefficient of determination (R2) in general exceeded 0.85 and these equations could be used to model the drop in milk production or predict production loss due to thermal stress. The rate of decline in daily milk production observed in the study was 2.13% per unit increase in THI. A general linear model that included THI, parity, and the stage of lactation as independent variables, and milk production as a response variable, was also tested. Parity and stages of lactation were observed to influence forenoon and afternoon milk production significantly (p < 0.01). The temperature-humidity index also had a significant effect on forenoon milk production (p < 0.05) and afternoon milk production (p < 0.01).


Assuntos
Indústria de Laticínios/estatística & dados numéricos , Resposta ao Choque Térmico/fisiologia , Lactação , Clima Tropical , Animais , Bovinos , Doenças dos Bovinos , Feminino , Temperatura Alta , Umidade , Modelos Lineares , Leite , Modelos Estatísticos , Dinâmica não Linear , Paridade , Gravidez , Estações do Ano , Temperatura , Tempo (Meteorologia)
18.
Animal ; 15(1): 100017, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33515993

RESUMO

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.


Assuntos
Doenças dos Bovinos , Hipocalcemia , Cetose , Ácido 3-Hidroxibutírico , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Hipocalcemia/diagnóstico , Hipocalcemia/veterinária , Cetose/diagnóstico , Cetose/veterinária , Lactação , Período Pós-Parto , Gravidez
19.
Animal ; 15(1): 100071, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33516029

RESUMO

The use of electronic devices to improve animal health, welfare and farm efficiency in precision livestock farming is a developing area of great scientific and commercial interest. In particular, the use of on-site dairy farm instruments to detect calving is a tool in reproduction livestock farming. The primary aim of this study was to validate the ability of the Moocall device (MD) to detect calving cows. In addition, behavioural changes in parturient dairy cows were evaluated using video-based observations. The MD was applied approximately 9 days before cow delivery. Observational sessions were conducted three times a day for each cow from the day before MD application to calving time. The sensitivity (Se) and specificity (Sp) at 3 and 24 h before calving were measured to test the effectiveness of the MD. In addition, behavioural changes were investigated before and after the MD application as well as before and during calving time. The 3 h Se and the 3 h Sp obtained were 95.2 and 71.4%, respectively. No false negatives were observed in the 24 h before delivery (24 h Se=100%) while the 3 h Se was 95.2%. The MD was well tolerated by the dairy cows since no change in behaviours was observed in this study among the cows with or without the MD, except for an increase in eating behaviour in the animals with the MD. As regards, the behavioural pattern during calving time (8 h before calving) in comparison with the previous phases, a significant increase in tail contraction frequency and raised tail position, and a decrease in eating behaviour and rumination time were observed. The first principal component (PC) was primarily explained by these variables, and calving cows best contributed to this PC. According to the results of the present study, the use of the MD can be a useful tool in detecting the moment of calving.


Assuntos
Doenças dos Bovinos , Parto , Animais , Bovinos , Fazendas , Comportamento Alimentar , Feminino , Lactação , Gravidez , Cauda
20.
Appl Environ Microbiol ; 87(6)2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33397699

RESUMO

Little is known about the drivers of critically important antibacterial resistance in species with zoonotic potential present on farms (e.g., CTX-M ß-lactamase-positive Escherichia coli). We collected samples monthly between January 2017 and December 2018 on 53 dairy farms in South West England, along with data for 610 variables concerning antibacterial usage, management practices, and meteorological factors. We detected E. coli resistant to amoxicillin, ciprofloxacin, streptomycin, and tetracycline in 2,754/4,145 (66%), 263/4,145 (6%), 1,475/4,145 (36%), and 2,874/4,145 (69%), respectively, of samples from fecally contaminated on-farm and near-farm sites. E. coli positive for bla CTX-M were detected in 224/4,145 (5.4%) of samples. Multilevel, multivariable logistic regression showed antibacterial dry cow therapeutic choice (including use of cefquinome or framycetin) to be associated with higher odds of bla CTX-M positivity. Low average monthly ambient temperature was associated with lower odds of bla CTX-M E. coli positivity in samples and with lower odds of finding E. coli resistant to each of the four test antibacterials. This was in addition to the effect of temperature on total E. coli density. Furthermore, samples collected close to calves had higher odds of having E. coli resistant to each antibacterial, as well as E. coli positive for bla CTX-M Samples collected on pastureland had lower odds of having E. coli resistant to amoxicillin or tetracycline, as well as lower odds of being positive for bla CTX-M IMPORTANCE Antibacterial resistance poses a significant threat to human and animal health and global food security. Surveillance for resistance on farms is important for many reasons, including tracking impacts of interventions aimed at reducing the prevalence of resistance. In this longitudinal survey of dairy farm antibacterial resistance, we showed that local temperature-as it changes over the course of a year-was associated with the prevalence of antibacterial-resistant E. coli We also showed that prevalence of resistant E. coli was lower on pastureland and higher in environments inhabited by young animals. These findings have profound implications for routine surveillance and for surveys carried out for research. They provide important evidence that sampling at a single time point and/or single location on a farm is unlikely to be adequate to accurately determine the status of the farm regarding the presence of samples containing resistant E. coli.


Assuntos
Farmacorresistência Bacteriana , Escherichia coli/genética , beta-Lactamases/genética , Envelhecimento , Amoxicilina/farmacologia , Animais , Antibacterianos/farmacologia , Bovinos , Doenças dos Bovinos/microbiologia , Ciprofloxacino/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Fazendas , Fezes/microbiologia , Estreptomicina/farmacologia , Temperatura , Tetraciclina/farmacologia
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