This study had the objective of elucidating factors involved in the causation of canine transmiss... more This study had the objective of elucidating factors involved in the causation of canine transmissible venereal tumour. Five hundred and two dogs brought to the animal clinic at Sokoine University of Agriculture were examined. Clinical examination and exfoliative cytology were used to distinguish dogs with (n = 173) and without (n = 329) the disease. Comparison was made between diseased and non-diseased dogs in terms of age, breed, sex, type of dog (use), and other extrinsic factors related to location and management. Management methods that allowed dogs to be in contact with each other predisposed them to the disease. Thus, guard dogs were noted to be at a higher risk of the disease than pets (odds ratio (OR) = 4.46). Dogs kept in high-density areas and in areas with high populations of stray dogs were more likely to contract canine transmissible venereal tumour compared to those raised in low-density areas and areas relatively free from stray dogs (OR = 6.13 and 6.78, respectively). It was concluded that management practices that allow unsupervised contact between dogs are among the important risk factors for canine transmissible venereal tumour.
Dairy herds from three counties in Denmark (n=2144) were monitored for a 1-year period to measure... more Dairy herds from three counties in Denmark (n=2144) were monitored for a 1-year period to measure the incidence rate (incidence-density) of clinical mastitis. Two different screening methods were evaluated to remove herds from the database for which the herdsman and veterinarian were suspected of under-reporting the mastitis cases which had occurred. One method was based upon agreement between clinical mastitis reports and measures of somatic cell counts of >1 million cells per ml. A second method was based upon agreement between cases reported through the regular disease-reporting system and cases reported on a management questionnaire. Depending upon the method of calculation and screening method used, rates of clinical mastitis varied between 36 and 48 cases per 100 cow-years at risk. The exclusion of herds because of documented non-reporting behavior (screening) resulted in a preponderance of herds with zero or very low incidence of mastitis being removed from the database. Following screening, the frequency distribution of herd mastitis incidence rates became decidedly more symmetrically and normally distributed.
This paper presents the second part of a questionnaire survey carried out in 2148 Danish dairy he... more This paper presents the second part of a questionnaire survey carried out in 2148 Danish dairy herds during 1994, as well as results from a similar survey carried out in 1983. The welfare status and trends during the 11 year period are discussed with respect to cattle housing systems and grazing procedures. Generally speaking, the results show that Danish dairy farmers in 1994 followed the common recommendations, i.e. 1) there are partitions between stalls in almost all tie stall houses, 2) feeding cubicles are seldom seen in cubicle houses, 3) bedding is provided for most cows, 4) saw dust as bedding for cows is not commonly used, and 5) the majority of cows and heifers are pastured during summer. However, adjustments in the following areas would be appropriate: 1) tie systems which restrict the cow's natural rising and lying should be phased out, and 2) loose housed heifers in boxes should have access to a bedded resting area.
Cotyledons (n=170) from dairy cattle were analysed for Coxiella burnetii by real-time (rt) PCR ta... more Cotyledons (n=170) from dairy cattle were analysed for Coxiella burnetii by real-time (rt) PCR targeting the IS1111a and icd genes. Positive cases (n=90) and a random selection of negative cases (n=20) were examined by histology, immunohistochemistry and, if infection level was high, by fluorescence in situ hybridisation. PCR results were compared to bulk tank milk (BTM) antibody levels. Placental infection was detected in cows from herds at all BTM antibody levels. However the likelihood of placental infection was generally higher in herds with intermediate or high BMT antibody levels than in herds with low antibody levels. Histological examination revealed a range of mostly mild cotyledonary changes; C. burnetii infection was only rarely associated with inflammation. This may explain why bovine Q fever is usually not clinically apparent. Nevertheless, infected cattle will shed C. burnetii at calving and this can occur even in herds without BTM antibodies.
... In general, the models behind these studies are not formulated for a clear defined production... more ... In general, the models behind these studies are not formulated for a clear defined production function (Fourichon et al., 1999 and Fourichon et al., 2000). ... Dairy farm efficiency studies by Bravo-Ureta (1986); Battese and Coelli (1988); Bailey et al. ...
A group of 152 Danish dairy herds infected with Streptococcus agalactiae during 1992 was compared... more A group of 152 Danish dairy herds infected with Streptococcus agalactiae during 1992 was compared with 177 randomly selected control herds in order to identify factors of importance for the transmission of this bacteria between herds. The diagnosis was based on a laboratory microbiological test on a bulk tank milk sample, and management information was collected by telephone interviews with the farmers. Results from logistic regression clearly indicate that purchase of cows or heifers increases the risk of a new Streptococcus agalactiae herd infection. Hygiene management risk factors inside the farm were also identified.
Additional file 1. Results of bivariate analysis of associations between farm status for pre-wean... more Additional file 1. Results of bivariate analysis of associations between farm status for pre-weaning diarrhea in mink and explanatory variables.
Treatment of mink kits with pre-weaning diarrhea (PWD) can be time-consuming and expensive for th... more Treatment of mink kits with pre-weaning diarrhea (PWD) can be time-consuming and expensive for the farmer, and the efficacy of the treatment procedure may be questioned. Evidence-based treatment protocols for application on affected animals at farms with outbreaks of PWD are lacking. In Denmark, the dams are sometimes treated with amoxicillin, however, it is unknown if it is passed on to the mink kits via the milk. The aim of the present study was to investigate if amoxicillin is transferred via the milk to the kits after oral (PO) and intramuscular (IM) treatment, respectively, of the dam. Moreover, we estimated the concentrations of amoxicillin continuously in serum from the kits up to 8 h after administration. The concentration of amoxicillin was not affected by the route of administration (P = .64) and serum reached the highest level after 8 h (34 ng/mL, CI 95% = [24.3-47.7]). The serum concentrations of amoxicillin in the mink kits achieved within 8 h were judged too low to exert antimicrobial impact on relevant bacterial species.
Finland's cold loose housing systems (CLH) for dairy cows have been compared to the more traditio... more Finland's cold loose housing systems (CLH) for dairy cows have been compared to the more traditional warm loose housing systems (WLH) in regard to the incidences of udder and ovarial disorders, ketosis, parturient paresis and metritis. For both systems approximately 10,000 calvings on 210 farms during the years 1996 and 1997 were modelled using survival analysis and two-level logistic regression in an observational cohort study. The results of the different multivariable models, the modelling process, model diagnostics and sample size and confidence limit analysis were combined in an attempt to estimate an unbiased risk ratio. The estimated risk ratios show that there are some differences in the incidence of production diseases between the 2 farming systems. It could be seen from the diagnostics that they were influenced considerably by the modelling process and some 'influential farms'. Even though some disease incidences differed statistically significantly, the observed differences were small so that we concluded that they should not influence the farmers decision making about whether or not to build a CLH in Finland.
Histological evaluation of bruises. Presence/absence (1/0) of: hyper-leukocytosis, leukocytes and... more Histological evaluation of bruises. Presence/absence (1/0) of: hyper-leukocytosis, leukocytes and hemorrhage in the dermis; neutrophils, hyper-leukocytosis, macrophages and hemorrhage in the subcutis; necrosis, neutrophils, macrophages, leukocytes in the interstitial space, leukocytes present intramuscularly, hyper-leukocytosis and hemorrhage in the muscle tissue. (XLSX 17 kb)
This study had the objective of elucidating factors involved in the causation of canine transmiss... more This study had the objective of elucidating factors involved in the causation of canine transmissible venereal tumour. Five hundred and two dogs brought to the animal clinic at Sokoine University of Agriculture were examined. Clinical examination and exfoliative cytology were used to distinguish dogs with (n = 173) and without (n = 329) the disease. Comparison was made between diseased and non-diseased dogs in terms of age, breed, sex, type of dog (use), and other extrinsic factors related to location and management. Management methods that allowed dogs to be in contact with each other predisposed them to the disease. Thus, guard dogs were noted to be at a higher risk of the disease than pets (odds ratio (OR) = 4.46). Dogs kept in high-density areas and in areas with high populations of stray dogs were more likely to contract canine transmissible venereal tumour compared to those raised in low-density areas and areas relatively free from stray dogs (OR = 6.13 and 6.78, respectively). It was concluded that management practices that allow unsupervised contact between dogs are among the important risk factors for canine transmissible venereal tumour.
Dairy herds from three counties in Denmark (n=2144) were monitored for a 1-year period to measure... more Dairy herds from three counties in Denmark (n=2144) were monitored for a 1-year period to measure the incidence rate (incidence-density) of clinical mastitis. Two different screening methods were evaluated to remove herds from the database for which the herdsman and veterinarian were suspected of under-reporting the mastitis cases which had occurred. One method was based upon agreement between clinical mastitis reports and measures of somatic cell counts of >1 million cells per ml. A second method was based upon agreement between cases reported through the regular disease-reporting system and cases reported on a management questionnaire. Depending upon the method of calculation and screening method used, rates of clinical mastitis varied between 36 and 48 cases per 100 cow-years at risk. The exclusion of herds because of documented non-reporting behavior (screening) resulted in a preponderance of herds with zero or very low incidence of mastitis being removed from the database. Following screening, the frequency distribution of herd mastitis incidence rates became decidedly more symmetrically and normally distributed.
This paper presents the second part of a questionnaire survey carried out in 2148 Danish dairy he... more This paper presents the second part of a questionnaire survey carried out in 2148 Danish dairy herds during 1994, as well as results from a similar survey carried out in 1983. The welfare status and trends during the 11 year period are discussed with respect to cattle housing systems and grazing procedures. Generally speaking, the results show that Danish dairy farmers in 1994 followed the common recommendations, i.e. 1) there are partitions between stalls in almost all tie stall houses, 2) feeding cubicles are seldom seen in cubicle houses, 3) bedding is provided for most cows, 4) saw dust as bedding for cows is not commonly used, and 5) the majority of cows and heifers are pastured during summer. However, adjustments in the following areas would be appropriate: 1) tie systems which restrict the cow's natural rising and lying should be phased out, and 2) loose housed heifers in boxes should have access to a bedded resting area.
Cotyledons (n=170) from dairy cattle were analysed for Coxiella burnetii by real-time (rt) PCR ta... more Cotyledons (n=170) from dairy cattle were analysed for Coxiella burnetii by real-time (rt) PCR targeting the IS1111a and icd genes. Positive cases (n=90) and a random selection of negative cases (n=20) were examined by histology, immunohistochemistry and, if infection level was high, by fluorescence in situ hybridisation. PCR results were compared to bulk tank milk (BTM) antibody levels. Placental infection was detected in cows from herds at all BTM antibody levels. However the likelihood of placental infection was generally higher in herds with intermediate or high BMT antibody levels than in herds with low antibody levels. Histological examination revealed a range of mostly mild cotyledonary changes; C. burnetii infection was only rarely associated with inflammation. This may explain why bovine Q fever is usually not clinically apparent. Nevertheless, infected cattle will shed C. burnetii at calving and this can occur even in herds without BTM antibodies.
... In general, the models behind these studies are not formulated for a clear defined production... more ... In general, the models behind these studies are not formulated for a clear defined production function (Fourichon et al., 1999 and Fourichon et al., 2000). ... Dairy farm efficiency studies by Bravo-Ureta (1986); Battese and Coelli (1988); Bailey et al. ...
A group of 152 Danish dairy herds infected with Streptococcus agalactiae during 1992 was compared... more A group of 152 Danish dairy herds infected with Streptococcus agalactiae during 1992 was compared with 177 randomly selected control herds in order to identify factors of importance for the transmission of this bacteria between herds. The diagnosis was based on a laboratory microbiological test on a bulk tank milk sample, and management information was collected by telephone interviews with the farmers. Results from logistic regression clearly indicate that purchase of cows or heifers increases the risk of a new Streptococcus agalactiae herd infection. Hygiene management risk factors inside the farm were also identified.
Additional file 1. Results of bivariate analysis of associations between farm status for pre-wean... more Additional file 1. Results of bivariate analysis of associations between farm status for pre-weaning diarrhea in mink and explanatory variables.
Treatment of mink kits with pre-weaning diarrhea (PWD) can be time-consuming and expensive for th... more Treatment of mink kits with pre-weaning diarrhea (PWD) can be time-consuming and expensive for the farmer, and the efficacy of the treatment procedure may be questioned. Evidence-based treatment protocols for application on affected animals at farms with outbreaks of PWD are lacking. In Denmark, the dams are sometimes treated with amoxicillin, however, it is unknown if it is passed on to the mink kits via the milk. The aim of the present study was to investigate if amoxicillin is transferred via the milk to the kits after oral (PO) and intramuscular (IM) treatment, respectively, of the dam. Moreover, we estimated the concentrations of amoxicillin continuously in serum from the kits up to 8 h after administration. The concentration of amoxicillin was not affected by the route of administration (P = .64) and serum reached the highest level after 8 h (34 ng/mL, CI 95% = [24.3-47.7]). The serum concentrations of amoxicillin in the mink kits achieved within 8 h were judged too low to exert antimicrobial impact on relevant bacterial species.
Finland's cold loose housing systems (CLH) for dairy cows have been compared to the more traditio... more Finland's cold loose housing systems (CLH) for dairy cows have been compared to the more traditional warm loose housing systems (WLH) in regard to the incidences of udder and ovarial disorders, ketosis, parturient paresis and metritis. For both systems approximately 10,000 calvings on 210 farms during the years 1996 and 1997 were modelled using survival analysis and two-level logistic regression in an observational cohort study. The results of the different multivariable models, the modelling process, model diagnostics and sample size and confidence limit analysis were combined in an attempt to estimate an unbiased risk ratio. The estimated risk ratios show that there are some differences in the incidence of production diseases between the 2 farming systems. It could be seen from the diagnostics that they were influenced considerably by the modelling process and some 'influential farms'. Even though some disease incidences differed statistically significantly, the observed differences were small so that we concluded that they should not influence the farmers decision making about whether or not to build a CLH in Finland.
Histological evaluation of bruises. Presence/absence (1/0) of: hyper-leukocytosis, leukocytes and... more Histological evaluation of bruises. Presence/absence (1/0) of: hyper-leukocytosis, leukocytes and hemorrhage in the dermis; neutrophils, hyper-leukocytosis, macrophages and hemorrhage in the subcutis; necrosis, neutrophils, macrophages, leukocytes in the interstitial space, leukocytes present intramuscularly, hyper-leukocytosis and hemorrhage in the muscle tissue. (XLSX 17 kb)
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