Search

Veterinary communication has evolved in the context of traditional veterinary tasks, such as diagnosing and treating sick animals, and this may encourage a directive communication style, in which the veterinarian acts as an expert, directing the client in what to do and how to do it. This type of communication style has been shown to evoke resistance to change in clients who are experiencing psychological ambivalence, a well-known aspect of farmers' herd health decisions. Veterinary herd health management (VHHM) constitutes an increasing proportion of the work of cattle veterinarians and often focuses on behavior change. The present study aimed to characterize communication styles of Swedish dairy cattle veterinarians involved in VHHM in relation to their skills in facilitating behavior change. A secondary aim was to investigate whether these skills differed among veterinarians depending on their experience in the veterinary profession or in VHHM. Audio-recorded role-play conversations (n = 123; reflecting VHHM telephone consultations) with 42 veterinarians involved in VHHM in Swedish dairy herds and audio-recorded on-farm consultations (n = 86) with 18 of those veterinarians were coded using a system developed to evaluate motivational interviewing (MI) skills. Motivational interviewing is a communication methodology aimed at facilitating clients' internal motivation to change. The MI Treatment Integrity (MITI) code identifies frequency counts of 10 verbal behaviors, and assesses 4 global variables on a Likert scale, based on 20 min of conversation. It also suggests 6 summary measurements of MI competency based on these 14 original variables. Of the 42 veterinarians, 39 also responded to a web questionnaire about their age, continuing education, and experience in the profession, in dairy herds and in VHHM. We analyzed associations between the 6 summary MITI variables from the role-play conversations and characteristics of the 39 veterinarians using logistic and linear multivariable regression models. Veterinarians in the role-play and on-farm conversations relied predominantly on giving information, questions, and persuasion in their consultation approaches. They generally did not explore the client's expectations or wishes regarding the agenda for the consultation, or acknowledge the client's right to make decisions about actions. Veterinarians gave advice without exploring the client's need for the advice or how the information was perceived. We found a significant reduction in so-called relational scores (Empathy plus Partnership) and an increase in MI-nonadherent behaviors (Persuasion plus Confront) as years of veterinary experience increased. Results showed that there is room for improvement in the communication style of veterinarians involved in VHHM. Wider literature suggests that training veterinarians in a client-centered communication methodology such as MI may increase the demand for and success of VHHM., (The Authors. Published by FASS Inc. and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).)

Diarrhea is common in young calves and is often caused by Cryptosporidium parvum infection. The aim of this study was to investigate if disinfection of calf pens with hydrated lime would reduce contamination of C. parvum oocysts and improve calf health in herds with C. parvum associated diarrhea problems. Four dairy herds with ongoing C. parvum associated calf diarrhea problems each participated in the study over six to seven months. During the study period, all pens/huts for young calves were cleaned according to the usual farm routine before a new calf entered. Hydrated lime was then used to disinfect half of the pens/huts. Diarrhea incidence was recorded by the farmers and by veterinarians, who clinically examined the calves every second month. In total, 402 calves participated in the study. The farmers detected diarrhea in 214 (53%) calves, with similar proportions in calves kept in lime disinfected and control pens. Age at diarrhea onset was significantly higher in lime disinfected pens than in control pens, 9.0 days and 7.6 days, respectively. There was no difference between the groups regarding duration or severity index recorded by the farmers. The body condition score in 6-8 week old calves was significantly higher in calves that had been kept in lime disinfected pens during their first weeks of life, indicating that calves in disinfected pens/huts were less affected by their infections. Faecal samples from 5 to 21 day old calves, were collected on four occasions at each farm (n = 95). Cryptosporidium positive samples were found at all samplings in all four herds. Cryptosporidium spp. was detected in 79 (83%) samples with no difference between lime disinfected and control pens. C. parvum was the dominant species. Two different C. parvum subtypes were found; IIaA16G1R1b in three herds and IIaA16G1R1b_variant in one herd. Only one subtype was found in each herd. Disinfection of calf pens with slaked lime delayed onset of diarrhea and improved the body condition in the calves, but did not affect diarrhea incidence or duration. Although lime disinfection alone will not be sufficient to control Cryptosporidium associated diarrhea in herds with extensive calf diarrhea problems, these results suggest that it can be a valuable complement to other measures., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

A preventive herd health approach will most likely reduce incidences of clinical and subclinical disease. Swedish veterinary organizations offer specific veterinary herd health management (HHM) programs, but these services are not used to a large extent. The aim of this study was to investigate dairy farmers' experience of HHM and the conditions for collaboration with veterinarians in HHM. Six focus group discussions were conducted in March 2015 in West Sweden. In total, 33 dairy farmers participated. The recordings were transcribed and coded using thematic analysis, and the transcripts were reviewed to identify potential factors indicating barriers for farmers to engage a veterinarian in HHM. The participants reported HHM to be important, but they had difficulty defining the actions included in the concept. They described a wide range of their work duties as preventive. The farmers' list of potential contributions by the veterinarians in HHM was strikingly short compared to the considerable number of preventive measures they performed themselves. Four main obstacles for farmers and farm managers to engage a veterinarian in HHM on their farm were identified in the analysis: "costs", "veterinary knowledge, skills, and organization", "farmer attitudes", and "veterinarian-farmer relationships". Costs were proposed as the main reason against engaging a veterinarian in HHM and included a high veterinary bill, low cost-benefit of veterinary services, and high costs to implement advice. Poor veterinary competence in HHM and poor knowledge about effective measures, practical farming, and farm economics were other important obstacles. Veterinarians were perceived to insufficiently describe their services and their benefits, and several participants felt they had never been offered veterinary HHM. Although veterinary HHM may be initiated by the farmer, the participants expected the veterinarian to have special responsibility for the initiation. A firm trust between farmer, staff, and veterinarian was considered crucial for veterinary HHM, but such trust takes a long time to build and can easily be disrupted by, for example, a veterinarian's poor communication skills or lack of time. Our findings suggest that Swedish dairy farmers and herd managers find disease prevention important and that they perform a wide range of tasks to prevent disease in their animals. However, they do not see what role the veterinarian can play, and veterinarians were mainly associated with treating unhealthy cows. In order to increase the use of veterinary HHM programs the services and potential benefits of such programs need to be communicated more proactively., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The aim of this study was to identify possible risk factors for 1-90 day calf mortality in large Swedish dairy herds. Sixty herds with a herd size of ≥160 cows were visited once between December 2005 and March 2006. Thirty herds were known to have low mortality (LM) and 30 were known high mortality herds (HM). Upon the visit, data about housing and management was collected from interviews with personnel responsible for the calves. The herd status regarding the calves' passive transfer (total protein), levels of α-tocopherol, β-carotene and retinol, and excretion of faecal pathogens (Cryptosporidium spp., Escherichia coli F5, rota and corona virus) was evaluated based on targeted sampling of high risk calf groups; in each herd, blood and faecal samples were collected from calves 1-7 and 1-14 days old, respectively. Similarly, the herd status regarding clinical respiratory disease in calves and history of respiratory virus exposure was evaluated based on lung auscultations and blood samplings of calves 60-90 days old. The median calf mortality risk (in calves 1-90 days of age) among HM herds was 9% (Range: 6-24%) and among LM herds 1% (Range: 0-2%). LM and HM herds were compared using five logistic regression models, covering potential risk factors within different areas: "Disease susceptibility", "Factors affecting the gastrointestinal tract", "Factors related to transmission of infectious disease", "Hygiene" and "Labour management". The percentage of calves, 1-7 days old, with inadequate serum concentrations of α-tocopherol and β-carotene were significantly higher in HM herds compared to LM herds and also associated with higher odds of being a HM herd (OR=1.02; p=0.023 and OR=1.05; p=0.0028, respectively). The variable "Average number of faecal pathogens in the sampled target group" was significantly associated with higher odds of being a HM herd (OR=4.65; p=0.015), with a higher average in HM herds. The percentage of calves with diarrhoea treated with antibiotics was significantly higher in HM herds and was associated with higher odds of being a HM herd (OR=1.08; p=0.021). The median age at death of calves in the age interval 1-90 days that died during a one-year period was significantly lower among HM herds (13 days) than in LM herds (24 days) (p=0.0013) The results indicate that gastrointestinal disorders may be an important cause of calf mortality in large Swedish dairy herds. Furthermore, our study provides additional indications that fat soluble vitamins might play an important role for calf health., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Associations between rearing conditions and the risk of culling in dairy cows were studied by survival analysis. Data were collected from 1039 Swedish Red cows, 1029 Swedish Holsteins, and 56 cows of other milk or cross-breeds, representing all female animals born in 109 Swedish herds during 1998. Length of productive life was defined as the number of days from 1st calving to culling. The applied Weibull proportional hazards model included time-independent effects of breed, housing from 3 to 7 months of age, number of housing changes before calving, grazing before 1st calving, herd median age at 1st calving, age at 1st calving, cow housing, herd lactational incidence risk of veterinary-reported clinical mastitis, and the random effect of herd. Time-dependent effects were year, month, the interaction year by month, parity, number of breedings, pregnancy status, the interaction parity by pregnancy status, herd mean milk-production level, relative milk yield within breed-parity, and veterinary-reported clinical mastitis. The lactation was divided into six stages in which pregnancy status was assumed to be known by the farmer and culling could occur. Median productive life time in culled cows was 780 d and 14% of the records were censored due to terminated data collection. An individual calving age of 28.2-30.9 months was associated with the highest culling risk, 1.2-fold higher than calving at < or = 25.3 months, whereas the risk decreased almost linearly with a higher herd median age at 1st calving. Housing in slatted pens with >7 calves from 3 to 7 months was associated with a 1.7-fold increase in risk, relative to litter pens. If a cow had changed housing system 4 times before 1st calving it increased the risk of culling 1.4 times, relative to two housing changes. These results show that rearing factors affect the productive life time of dairy cows in Swedish family operations.

We carried out a longitudinal study of 122 dairy herds in southwest Sweden to investigate relationships of rearing conditions and health with heifer breeding performance and to estimate the incidence of clinical diseases and survival until 1st calving. A total of 3081 animals born in 1998 (47% Swedish Red; 50% Swedish Holstein breed) were followed from birth until calving, culling or death. Information about housing, management, breeds and dates of birth, breeding and calving was obtained from farmers. Diseases were recorded by farmers and veterinarians; antibiotic treatment was used in < 25% of all cases. Median time to breeding was 17.5 months, 64% of all heifers bred by AI conceived at 1st breeding, and median time to calving was 27.6 months. Age at 1st breeding (log-transformed), conception at 1st breeding (binary), and age at 1st calving (log-transformed) were analysed with three mixed models, accounting for clustering by considering random-intercept and random-slope effects at the herd level. Around 40 potential predictors or confounders were recorded and considered for modelling. Time to breeding and calving increase greatly with the time heifers spend grazing, although up to 5 months of grazing before 1st calving appears to be more favourable than no grazing at all. The effect of grazing differs depending on the season of birth. Zero-grazed heifers calve 20% later if exposed to indoor ammonia concentrations > 10 ppm after start of breeding. There is considerable variation between herds in breeding performance, except for conception at 1st breeding-limiting the potential for improving conception by herd measures. Observed total disease incidence rate was 14 per 100 animal-years from 7 months of age to estimated conception and 4.7 per 100 animal-years from conception to calving, with great variation between herds. Infectious diseases were predominant, and diarrhoea, respiratory disease and ringworm were the most common diagnoses. Eight hundred and fifty-three heifers left the study before calving, due to herd exits (incidence risk 0.073%), selling off live (0.061%), spontaneous deaths (0.050%) or slaughter (0.092%).

Information regarding health, management, and housing from birth to first calving was collected for 1,029 Swedish Reds, 991 Swedish Holsteins, and 40 heifers of crossbreed or other breeds on bimonthly farm visits made by 3 project veterinarians to 107 dairy herds in southwest Sweden. Additional data were obtained from the official milk- and health-recording program. Milk production at first test day after calving [energy-corrected milk (ECM)1] and during the first 305 d of lactation (ECM305), respectively, were analyzed by 2-level (animal; herd) linear regression, after initial screening by univariable analyses of 67 potentially important predictors. The ECM1 ranged from 7.9 to 48.0 (median = 27.1) kg, and ECM305 ranged from 3,764 to 12,136 (median = 8,006) kg. In the final models, factors associated with ECM1 or ECM305 or both were age at first calving, body condition score at first service, breed, calfhood diarrhea, calving season, composite somatic cell count at first test day, daily weight gain from weaning to first service, housing system after calving, and increase in concentrate fed around calving. Higher age at calving was associated with higher production. Production also increased with higher daily weight gains from weaning to first service. Swedish Holsteins produced more than Swedish Reds, cows calving in May to September produced more than those calving during other months, and cows housed in short stalls after calving produced more than those in cubicles. Body condition scores > or =3.2 at first service were associated with lower ECM305 than scores < or =2.9. Animals that contracted mild diarrhea during their first 3 mo of life had lower ECM305 than animals without diarrhea, whereas animals receiving a high increase in concentrate pre- and postcalving had higher ECM305 than those subjected to a more moderate increase. Cows with a composite somatic cell count >1 million cells/milliliter at first test day produced less milk on the same day than cows with lower counts. It was concluded that rearing factors and calfhood health status can influence first lactation milk production.

The serum concentration of haptoglobin (S-Hp) was measured in 833 group-housed dairy calves from nine herds in south-west Sweden once at 24-56 days of age to evaluate the potential of S-Hp as an indicator of clinical respiratory-tract disease (CRD). Presence of disease (treated and non-treated) was assessed clinically by farmers and by a project veterinarian visiting the farms every third week. The median S-Hp of healthy calves was 0.06g/L (80% central range: 0.04-0.23), of calves with diarrhoea within the 10 days before sampling 0.07g/L (80% central range: 0.04-0.63), and of calves with CRD within the 14 days before sampling 0.09g/L (80% central range: 0.04-0.69). Eight different cut-off values were used to define a positive S-Hp analysis result: >0.05, >0.06, >0.07, >0.08, >0.09, >0.10, >0.15 and >0.20g/L. A rectal temperature >39.5 degrees C was denoted as fever. A positive result of five different diagnostic tests for CRD was defined as: (1) a positive S-Hp with fever absent, (2) a positive S-Hp with fever present, (3) either a positive S-Hp or fever, (4) both a positive S-Hp and fever, and (5) fever (regardless of S-Hp). The sensitivity (Se) and specificity (Sp) of each test were calculated from regression coefficients of generalized linear mixed models of the binary test results, applying a logit link. Apart from CRD status (within the 14 days before sampling; no or yes), the models included sex (bull or heifer), and for the test based on S-Hp alone, also rectal temperature (fever, no or yes). Confidence intervals (CI) of Se and Sp were estimated by simulation. Based on Se, Sp, and areas under Receiver Operating Characteristics curves, test 3 was considered the best. At optimal performance, giving equal importance to type I and II errors, i.e. at a S-Hp cut-off of 0.15g/L in heifer calves, Se was 0.64 (95% CI 0.50-0.77) and Sp 0.71 (95% CI 0.60-0.80), and at a S-Hp cut-off of 0.08g/L in bulls, Se was 0.52 (95% CI 0.40-0.64) and Sp 0.80 (95% CI 0.74-0.85). The other tests were judged as unsatisfactory indicators of CRD. In heifers, the proportion of CRD-positive calves in the herd was strongly associated with the proportion of test positives (S-Hp or fever; S-HP and fever), suggesting potential as a herd-level indicator.

Housing calves in large groups is associated with a higher risk of respiratory disease and with increased difficulties in identifying diseased animals compared with single housing. The aim of the present study was to investigate the effect of clinical disease on some behaviors recorded by automatic milk feeders in pre-weaned dairy calves. The experiment included 27 calves from a Danish research farm and 41 calves from a Swedish research farm. The calves were fed restrictively from a computer-controlled milk feeder, and all calves were subjected to daily clinical examinations for 3 to 26 d, with information gathered on general condition, nasal discharge, lung auscultation findings, coughing, signs of dehydration, naval status, rectal temperature, fecal consistency, and presence of chin abscess, arthritis, umbilical hernia, poor body condition, and poor hair coat. Calves suffering from diarrhea, respiratory disease, fever, or unspecific decreased general condition for more than 2 d were considered to be diseased and were declared to have recovered when they had been free of clinical signs of the disease for at least 2 d. The effects of clinical status (healthy, diseased) on the number of rewarded and unrewarded visits to the calf feeder and drinking rate, respectively, were analyzed by variance component analysis using a mixed model. Milk consumption on diseased and nondiseased days within calves was compared using a Wilcoxon signed rank test. In total, 53 of the calves were diagnosed as diseased during the study period. All cases of diseases were mild and were associated with an unaffected or only mildly affected general condition. Diarrhea was diagnosed in 51 calves, 6 of which also had respiratory disease. In 2 calves, respiratory disease was the only diagnosis. Eleven calves had an unspecific decreased general condition. The number of unrewarded visits was significantly reduced when calves were diseased. In Swedish calves, there was also a tendency for rewarded visits to be reduced during diseased days. Drinking rate and number of rewarded visits increased with increasing age. No effect of clinical status on milk consumption was detected. The number of unrewarded visits was the most sensitive of the 4 feeding behaviors monitored to indicate clinical disease in calves fed restricted milk volumes.

The mortality of 8,964 heifer calves born in 122 dairy herds in southwest Sweden in 1998 to 2000 was monitored from January 1998 until December 2000. Farmers were requested to send carcasses for necropsy from animals that died from 1 d of age to first calving. Age and seasonal patterns of mortality were investigated using Kaplan-Meier curves. The median herd-level mortality risk was 2.1%. In total, 3.1% of the animals died before 90 d of age, 0.9% between d 91 and 210, and 2.2% between d 211 and first calving or d 810 (27 mo of age). The median age at death was 50 d and the risk of dying was highest during the first week of life. Of the 421 dead animals, 236 (56%) were subjected to either postmortem examination or were diagnosed as having died from trauma based on information from the farmers. In total, pneumonia was the most common cause of death (27%). However, in calves less than 31 d old, enteritis was the most common cause of death; in young stock 211 to 450 d old, trauma dominated; and in young stock more than 450 d old, trauma and calving-related diseases accounted for a majority of the mortality. The largest proportion of deaths was observed from January to March, and in June. Kaplan-Meier curves suggested that housing in small-group pens was associated with the lowest mortality (other housing systems were single pens and large-group pens with automatic milk feeders), but the association was not significant.

The dynamics of bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus 3 (PIV-3), bovine corona virus (BCoV) and bovine viral diarrhoea virus (BVDV) infections were studied in 118 dairy herds in south western Sweden. By using serology on paired samples from three approximately 7 vs. approximately 15-month-old calves per herd, the propagation of infections was investigated over about a 1-year period. The results implied that at least 74% of calves had experienced one or more of the monitored infections at the age of approximately 7 months (Sample 1, Spring); 30%, 48%, 34% and 8% were seropositive to BRSV, PIV-3, BCoV and BVDV, respectively. Seroconversions to BRSV, PIV-3, BCoV and BVDV occurred in 26%, 38%, 50% and 3% of seronegative animals and 63% had antibodies against two or more infections at approximately 15 months (Sample 2). In total, 90-97% of animals that were seropositive in Sample 1 remained positive in Sample 2. A significant association was found between BVDV and BCoV (P = 0.01). Moreover, a significantly higher proportion of herds in which no calves had a recorded history of respiratory disease (n = 15) were classified as negative to all four infections monitored when compared to herds in which disease was observed (P = 0.0002). This study showed a high infection burden in young animals and effective spread of BRSV, PIV-3 and BCoV in one area of Sweden. BVDV infections were restricted to a few herds, reflecting the effect of a voluntary control program against BVDV in Sweden.

The health status of 2947 heifer calves born in 1998 and raised in 122 Swedish dairy herds was monitored from birth to 210 days of age. Disease occurrence was recorded by farmers and by veterinarians who visited the farms six times yearly, examined the calves clinically and auscultated their lungs. The incidence risks of diarrhoea, ringworm and clinical respiratory-tract disease (CRTD) in calves from 3 to 7 months of age were 2.7%, 5.6% and 5.7%, respectively. The herd-level incidence risks of the three diseases were zero in 63.1%, 76.2% and 48.4%, respectively, of the herds. In positive herds incidence risks were 2.2-46.4%, 2.6-47.0% and 2.2-53.3%, respectively. The associations between the potential risk factors age at first grazing, air quality, birth place, feeding of colostrum, hygiene, number of animals, age range within the pen or building, pen area, pen location, previous housing type, present housing type, previous disease and season, and each of three binary outcome variables (diarrhoea, increased respiratory sounds and CRTD) were evaluated using two-level (calf; herd) variance component logistic models. Predictors significantly associated (P<0.05) with diarrhoea were pen area, season and the interaction between pen location and previous CRTD. Previous CRTD, season and heart girth at weaning were significantly associated with moderately to severely increased respiratory sounds. Predictors significantly associated with CRTD were previous diarrhoea, previous housing and season. It was concluded that the incidence of diarrhoea and CRTD in 91-210-day-old Swedish dairy calves is higher than previously reported from dairy herds in Sweden and the USA, and that diarrhoea, increased respiratory sounds and CRTD are associated with season, a history of disease during the first 90 days of age and, to some extent, housing factors.

A total of 3081 heifer calves in 122 Swedish dairy herds were monitored from birth to first calving, and all their diseases and treatments were recorded. There were 1268 cases of infectious diseases, of which 335 (26.4 per cent) were treated with antimicrobial drugs. Just over 90 per cent of the treatments were given during the first 210 days of the calves' lives, but only 61.8 per cent of the total quantity of antimicrobial drugs was consumed during this period. The most common diseases from birth until 210 days were respiratory diseases and diarrhoea; treatments for mastitis and interdigital phlegmon (foul in the foot) were more common after 420 days of age. Slightly more than 60 per cent of the treatments were given by the farmers without prior consultation with a veterinary surgeon.

The health of 3081 heifer calves born in 122 dairy herds in the south-west of Sweden from 1 January to 31 December, 1998, was monitored from birth until 90 days of age. The calves were kept either in individual pens (n=2167), in group pens, with 3-8 calves to a pen and manual feeding of milk (n=440), in group pens with 6-30 calves per pen and an automatic milk-feeding system (n=431), or with their dams (n=43). Disease incidence was recorded by farmers and project veterinarians, who clinically examined the calves and auscultated their lungs every 2-3 months. A disease was graded as 'severe' if the general loss of condition or of appetite in the calf continued for >2 days or if the animal suffered severe weight loss due to the disease. The effects of season, breed, housing, and type of colostrum feeding, and time, place and supervision of calving on the incidences of diarrhea, severe diarrhea, respiratory disease, other infectious disease and moderately to severely increased respiratory sounds, were analyzed by logistic-regression models (with herd as a random effect). The total morbidity rate was 0.081 cases per calf-month at risk. Incidence rates of arthritis, diarrhea, omphalophlebitis, respiratory disease and ringworm were 0.002, 0.035, 0.005, 0.025 and 0.009 cases per calf-months at risk, respectively. The odds ratios for diarrhea and severe diarrhea were increased in Swedish Red and Whites (OR: 1.6, 2.3) and in calves that received colostrum from first-lactation cows (OR: 1.3-1.8), and for severe diarrhea in calves born in summer or that received colostrum through suckling (OR: 1.7, 1.8). The odds ratios for respiratory disease and increased respiratory sounds were increased in calves housed in large-group pens with an automatic milk-feeding system (OR: 2.2, 2.8). Supervision of calving was associated with a decreased odds ratio for respiratory disease (OR: 0.7) and birth in individual maternity pen or tie stalls with a decreased odds ratio for increased respiratory sounds (OR: 0.5-0.6). Cross-breeds with beef breeds were associated with increased odds ratios for increased respiratory sounds (OR: 2.1-4.3) and colostrum from second-lactation cows and birth during night for other infectious disease (OR: 1.6, 1.5).

The objective of this study conducted in 75 herds was to investigate the presence and significance of Criptosporidium parvum and Giardia intestinalis in Swedish dairy calves in comparison with rotavirus, coronavirus and Escherichia coli K99+. The farmers were asked to collect faecal samples from each heifer calf that had diarrhoea between birth and 90 days of age, and also from a healthy calf of the same age. In total, 270 samples were collected and analysed. C. parvum, either alone or together with G. intestinalis and/or rotavirus, was detected in 16 (11%) and 6 (5%) of the samples from diarrhoeic and healthy calves, respectively. Even though a higher proportion of diarrhoeic calves shed C. parvum, the difference between the groups was not statistically significant (p = 0.067), possibly due to the low number of positive samples. G. intestinalis was found in 42 (29%) of the diarrhoea samples and in 29 (23%) of the samples from healthy calves. Rotavirus and coronavirus were demonstrated in 24% and 3% of the diarrhoea samples, respectively, whereas E. coli K99+ was only found in samples from 2 healthy calves. C. parvum and G. intestinalis were found in samples from calves 7 to 84 days of age and during all seasons. The results confirm that C. parvum is present in Swedish dairy herds and might have clinical significance. G. intestinalis was the most common agent found but the importance of this parasite remains unclear. Both parasites have suggested zoonotic potential and thus warrant further attention. In addition, rotavirus is a major pathogen in neonatal enteritis in Sweden, whereas coronavirus and E. coli K99+ seem to be of less importance.

Infections with internal parasites are one of the most important causes of reduced productivity in first-grazing season cattle (FGSC). In conventional herds, nematode infections can be controlled by prophylactic anthelmintic treatments, but this is prohibited in organic production. The purpose of this investigation was to monitor the status of internal parasitism on 15 organic cattle enterprises in southwestern Sweden during the 1997 and 1998 grazing seasons, and to estimate the benefits of some management practices in parasite control. On each farm, the numbers of Eimeria alabamensis oocysts per gram of (opg) faeces were counted in seven fresh dung pats collected from the paddock 8-10 days after the turnout of FGSC. Faecal samples from 5 to 15 FGSC were also analysed for nematode eggs per gram (epg) faeces at four occasions during each grazing season. In addition, the FGSC and one group of second-grazing season cattle (SGSC) were weighed at turnout and housing and at the same time blood samples were collected, and analysed for serum pepsinogen concentration and antibodies against the lungworm, Dictyocaulus viviparus. On seven farms, 1-6 samples with more than 100000 opg were found, indicating considerable pasture contamination by E. alabamensis. However, clinical signs of coccidiosis were not observed. The highest outputs of nematode eggs were observed 45-55 days after turnout. More than 500 epg were only observed in 12 (2.2%) of the calves in 1997 and in three (0.6%) animals in 1998. Only 1% of the serum samples had pepsinogen values exceeding 3.6 U tyrosine, indicative of subclinical Ostertagia ostertagi infection. Lungworm infection was detected in five and nine herds in 1997 and 1998, respectively. The number of seropositive animals on these farms ranged between one (10%) and seven (70%). Clinical signs of dictyocaulosis were observed on two farms. The results indicate that dictyocaulosis is a problem in organic dairy herds in Sweden. On the other hand, the study shows that good management such as usage of parasite safe pastures and supplementary feeding may help control gastrointestinal parasites.

The aims of the present study were to investigate the excretion of Eimeria alabamensis oocysts by young cattle during their first grazing season and during the first 16 days of their second grazing period. In trial 1, nine first-season grazing heifers were studied and found to have become infected with E. alabamensis shortly after turnout. The next grazing period they were turned out on to a permanent pasture together with two first-season grazing calves. Faecal samples were collected before turnout and then daily from day 3 to day 16. The second-season grazing heifers excreted insignificant numbers of E. alabamensis oocysts, whereas one of the two first-season grazing calves excreted up to 703,000 oocysts/g of faeces (OPG), indicating that the pasture was contaminated. In trial 2, faecal samples were collected from 12 calves before their first turnout in May, daily from day 2 to day 20 after turnout and then once a week until the end of September. The calves grazed pastures used in previous years by first-season grazing calves. Nine of the calves developed clinical E. alabamensis coccidiosis 4-7 days after turnout and excreted more than 950,000 OPG on days 9-10. By day 17 the oocyst excretion had decreased below 900 OPG and remained low throughout the rest of the grazing season. The results of the two studies indicate that reinfections with E. alabamensis are of little clinical importance in calves grazing contaminated pastures, and that young stock infected with E. alabamensis during their first grazing season may be used to cleanse contaminated pastures without risk of developing clinical coccidiosis.

The efficacy of calcium propionate for the prevention of parturient paresis (milk fever) was compared with that of calcium chloride using 194 cows that had experienced milk fever during the previous calving. The cows were mainly of the Swedish Red and White and Swedish Friesian breeds and were divided randomly into an experimental group (n = 99) and a control group (n = 95). The cows in the experimental group received up to six boluses of 20 g of calcium as calcium propionate between 36 h before and 24 h after calving; the cows in the control group received up to four doses of 54 g of calcium as a commercially available oily solution of calcium chloride during the same period. Incidence of milk fever was recorded as the percentage of cows that were treated by a veterinarian because they showed clinical signs of the disease and had a blood calcium concentration less than 8.0 mg/dl. Twenty-five (25.3%) cows in the experimental group and 22 cows (23.2%) in the control group developed milk fever. The incidence of milk fever for cows in both groups was significantly lower than the 36.0% found in 713 cows that had experienced milk fever during their previous calving but received no prophylactic treatment. Therefore, calcium propionate was considered to have had a significant preventive effect, comparable with that of calcium chloride.

Twelve calves aged 6-10 months, and 12 calves aged 10-16 months were turned out onto a permanent pasture known to have been contaminated with oocysts of Eimeria alabamensis during the previous year. Two days after turnout, six of the older calves and six of the younger were each treated with one bolus per 200 kg bodyweight containing 1.6 g baquiloprim and 14.4 g sulphadimidine. The other 12 calves were left untreated. The excretion of Eimeria oocysts, the faecal dry matter and the weight gain of treated and untreated calves within each age group were compared during the first 3 weeks on pasture to assess the efficacy of the bolus in preventing E. alabamensis coccidiosis. All the older of the untreated calves and four of the younger developed gruel-like to watery diarrhoea 4-7 days after turnout. The faecal consistency of the treated calves remained firm and they lost significantly less weight than the control calves during the first 13 days on pasture. The treated calves also excreted significantly fewer oocysts during the first 20 days of grazing; their oocyst excretion remained low during days 8-10 when all but one of the diarrhoeic control calves excreted more than 850,000 oocysts per gram faeces (OPG). Starting on days 12 to 14 the oocyst excretion of 8 of the treated calves increased to 20,000-65,000 OPG and of 2 calves to 210,000-240,000 OPG. There was no difference in oocyst output between treated and untreated calves from the fourth week of grazing and no difference in weight gain among the younger calves. In the older calves there was a tendency for the untreated calves to gain more weight than treated calves.

Six of the 33 calves born in a Swedish dairy herd during a period of four months developed laminitis when they were eight to 12 weeks old. The clinical signs included difficulty in rising, a stiff gait, overgrown claws and haemorrhages in the sole horn. Samples of blood were taken from four of the calves when they had shown signs of laminitis for two to seven weeks; the serum concentrations of calcium, phosphorus and vitamin D3, the activities of aspartate aminotransferase and glutathione peroxidase, and the patterns of serum proteins were within their normal ranges. The feet of the same four calves were examined after slaughter; the third phalanx of each calf was rotated and its distal end osteolytic. Histologically there was separation and degeneration of the squamous cells of the white line, and thromboses and vasculitis in the fine vessels of the corium. Four of the six affected calves were persistently infected with bovine viral diarrhoea virus and one had antibodies against the virus. From six weeks of age the calves had been fed rye wheat, a hybrid seed rich in starch, and this may have contributed to the outbreak of laminitis.

From a permanent pasture where young cattle had contracted coccidiosis due to Eimeria alabamensis 2 years previously, hay was harvested and fed to six 2-4 month old calves 15 days, 4 months or 8 months after being harvested. The excretion of oocysts by these exposed calves was compared with that by five control calves of similar age which were housed in the same premises but fed hay from a 'coccidia-free' field. All calves fed the contaminated hay developed patent E. alabamensis infections and excreted 142000 to 4.2 million oocysts of this species per gram of faeces starting 8 days after the hay was first fed. Five of them had soft (porridge-like to gruel-like) faeces and/or poor appetite. The control calves excreted no or very few oocysts and had firm faeces and unaffected appetite. It is concluded that making hay from pastures contaminated with oocysts of E. alabamensis is unsatisfactory if the hay is to be used for feeding young cattle.

Twelve calves which had been immunised with a trickle dose of altogether 100,000 oocysts of Eimeria alabamensis 16 days before turnout and 12 uninoculated calves were monitored during their first 20 days of grazing on a pasture naturally contaminated with oocysts of E. alabamensis. Eleven of the uninoculated calves developed gruel-like diarrhoea 3-6 days after turnout and excreted more than 850,000 oocysts/g of faeces (OPG) a few days later. In contrast, none of the immunised calves developed clinical coccidiosis and most of them excreted only a few oocysts. They lost on average 18 kg less in bodyweight than the unimmunised control calves. On day 21 all the calves were rehoused and on day 27 they were challenged with 10 million sporulated oocysts of E. alabamensis and turned out onto the same pasture. Only insignificant clinical signs were observed in 2 of the immunised calves and in one of the control calves. It was concluded that immunisation is a promising control measure for E. alabamensis coccidiosis. However, fewer or attenuated oocysts must be used, as 9 of the 12 inoculated calves developed clinical coccidiosis before turnout as a result of the immunisation doses.

The excretion of Eimeria oocysts, the faecal dry matter and the weight gain of three groups of 12 calves, were compared during their first 20 days of grazing on a pasture known to have been contaminated with oocysts of Eimeria alabamensis during the previous year. On the day of turnout (day 0) the calves in group 1 were each treated with one bolus per 200 kg bodyweight containing 1.6 g baquiloprim and 14.4 g sulphadimidine. The calves of group 2 received the same treatment on day 3, and the calves of group 3 were left untreated. Eleven of the untreated calves developed clinical coccidiosis due to E. alabamensis and excreted more than 850,000 oocysts/g of faeces 8-10 days after turnout. Seven of the calves in group 1 and five of those in group 2 developed diarrhoea, but it was milder and/or less persistent than in the untreated calves. The treated calves excreted significantly fewer oocysts and lost significantly less weight than the untreated calves. On day 21 all the calves were housed and on day 27 they were challenged with 10 million sporulated oocysts of E. alabamensis and turned out on to the same pasture. Only minor clinical signs were observed in some of the calves, indicating development of immunity in all groups. However, there was a tendency for the calves treated on day 3 to excrete more oocysts and to gain less weight than the other calves.

The extent to which oocysts of the coccidian parasite Eimeria alabamensis can survive the winter and cause clinical coccidiosis in different parts of Sweden was investigated. Fecal samples were collected between May and July 1993 from calves on 59 farms where calves had grazed the same pasture for at least 5 consecutive years. The farms were situated in 9 regions of Sweden with different climatic conditions in the winter. On each farm, 5 samples of feces were collected from the floor of the calf-house before the calves were turned out in the spring, and again from the pasture on days 4 or 5, 8 or 9 and 10 or 11 after they were turned out. Overwintering of oocysts of E. alabamensis was considered to have occurred if an increase in the excretion rate of oocysts of this species could be demonstrated 8 to 11 days after calves had been turned out to pastures that had not been grazed since the previous autumn. Oocysts were shown to have overwintered on 27 farms, representing all 9 regions. Samples from 20 (34%) of the farms representing all the climatic regions contained more than 850,000 oocysts per g of feces. This was comparable with the numbers found in animals with clinical coccidiosis due to E. alabamensis. Delaying turnout until the beginning of July did not affect the infection rate of the calves. However, calves which were turned out to pastures that had been grazed by older cattle or horses, either earlier in the spring or in previous years, excreted significantly fewer oocysts than calves which were turned out to pastures that had been grazed only by calves. A questionnaire answered by 321 dairy farmers revealed that of the 298 farmers who turned their first-season grazing cattle out to traditional pastures, 179 (60%) had used the same pasture for at least 5 years. These 179 farmers had experienced a significantly higher incidence of diarrhoea in their calves during the first 2 weeks at pasture than those farmers who had used different pastures.

Two trials were carried out to assess the changes in blood composition of calves infected either experimentally or naturally with Eimeria alabamensis. In the first, 12 calves were dosed orally with 10 to 400 million sporulated oocysts and compared with three control calves. The second trial used eight calves turned out to graze a permanent pasture known to induce E alabamensis coccidiosis in calves and eight calves turned out on to a previously ungrazed pasture. In both trials the serum activities of glutamate dehydrogenase (GLDH) and alkaline phosphatase (AP) and the serum concentration of total bile acids decreased in the infected animals while total bilirubin increased. The changes in GLDH, bile acids and bilirubin were most pronounced just before the calves began to excrete oocysts. In the first trial the lowest AP activity was observed 10 days after infection, but in the second its activity continued to decrease throughout the trial. In the first trial haematology, serum fibrinogen, total protein and protein fractions were also investigated. All the significant changes were small and the potential of the investigated blood components as diagnostic markers is therefore minimal.

Large numbers of oocysts of Eimeria alabamensis have been found in the faeces of calves suffering from diarrhoea shortly after being turned out to pasture. To investigate the source and clinical significance of this coccidial infection, the numbers of oocysts excreted, the consistency of the faeces and the growth rates of four groups of 12 calves were compared. Group I calves were kept indoors and their diet was unchanged, Group II calves were turned out onto a previously ungrazed pasture, Group III calves were turned out onto a permanent pasture and Group IV calves were kept indoors and fed cut grass from a previously ungrazed field. Eight days after the animals were turned out there was an almost 1000-fold increase in the numbers of oocysts in the faeces of Group III calves, the dominant species being E. alabamensis, but there were only minor fluctuations in the numbers of oocysts excreted by the other groups. It was therefore concluded that the source of the infection was oocysts that had overwintered on the permanent pasture. Most of the calves in Group III developed watery diarrhoea 5 days after turnout, but there was only a slight softening of the faeces of the calves in Groups II and IV at about the same time. The faeces of the calves in Group I was of firm consistency throughout the trial. The calves in Group III lost 18 kg during the 24 day period following turnout, whereas the calves in the other groups gained between 6 and 18 kg.

Four groups of three conventionally reared 2-month-old bull calves were inoculated with 10 million to 400 million sporulated oocysts of Eimeria alabamensis isolated from Swedish calves which had diarrhoea while at pasture. Their appetite, clinical condition, growth rate and the dry matter content of their faeces were compared with those of three similar but uninoculated calves. The prepatent period was 6-8 days, and the period during which large numbers of oocysts were excreted was 2-7 days. In two of the inoculated calves only a slight softening of the faeces was observed. The other ten calves developed watery diarrhoea, had a poor appetite and appeared depressed. The clinical signs were most severe in the calves which received the highest doses and included signs of abdominal pain and a reluctance to rise. The growth rates of the infected calves were significantly reduced for 18 days after inoculation, and 71 days after inoculation they had not compensated for this period of reduced growth rate.

Faecal samples were collected 3 times a week for 6 weeks from 22 paripartal cows and for up to 15 weeks after birth from 27 calves in 3 herds, to determine the numbers of Eimeria oocysts excreted and the age at which the calves first excreted oocysts. Only low numbers of oocysts were excreted by the cows and no oocysts were detected in 93% of the samples. However, half the cows excreted oocysts at least once. The age at which the calves first excreted oocysts ranged from 2.5 to at least 15 weeks, and there was a significant difference between the herds in their mean age at first excretion. Oocysts of Eimeria alabamensis, E. auburnensis, E. bovis and E. ellipsoidalis were found in numbers ranging from 7 to 8450 oocysts per gram faeces. About 50% of the calves excreted oocysts before they were transferred to group pens. The primary source of infection of the calves was probably their penmates or the previous occupants of the pens, and the cows probably played a subsidiary role.

The numbers of Eimeria oocysts per gram (opg) and the dry matter content of 449 faecal samples taken from 54 calves in 8 herds in south west Sweden were determined during the last 2 weeks before and the first 3 weeks after the animals were turned out to pasture. While they were housed only between 0 and 580 opg were found and in 2 of the herds the numbers of oocysts remained low after turn-out. In the other 6 herds the numbers of oocysts increased after 8 to 10 days and reached a peak of between 1080 and 80,803 opg 9 to 18 days after turn-out. By 21 to 24 days after turn-out the opg-values had declined to their initial levels. Eimeria alabamensis accounted for most of the increase, but small numbers of oocysts of E. auburnensis, E. bovis, E. bukidnonensis, E. cylindrica, E. ellipsoidalis, E. pellita, E. subspherica, E. wyomingensis and E. zuernii were also observed. The interval between turn-out and the start of the increase in excretion of oocysts corresponded closely to the prepatent period of E. alabamensis and overwintered oocysts were therefore the most likely source of the infection. In 6 of the herds the dry matter content of the faeces of the calves decreased after turn-out and 56% of the calves had clinical diarrhoea. Although it cannot be excluded that change of diet may have contributed to these symptoms, E. alabamensis infection is suggested as a potential cause of diarrhoea and loss of condition in calves in Sweden during their first weeks on pasture.

Relationships between heifer rearing conditions and the risk of veterinary-reported clinical mastitis (VRCM) during productive life were studied by generalized linear mixed modeling at the lactation level. Data consisted of 5,693 lactations in 2,126 Swedish Reds, Swedish Holsteins, or dairy cows of other or mixed breeds, representing all female animals born in 110 herds in southwest Sweden in 1998. During a lactation, a cow was defined as affected by VRCM if one or more cases were reported by a veterinarian, starting from 7 d precalving. The applied model of VRCM included effects of breed, parity, diarrhea between 3 and 7 mo of age, increase in body weight from weaning to first breeding, increase in daily concentrate ration before first calving, herd-level median age at first calving, cow housing, and random effects of cow and herd. The VRCM incidence was 14% in a given lactation, or 0.11 cases/cow annually; 31% of the cows had VRCM at least once during their productive life. Ninety percent of the variation in mastitis risk was due to factors at the lactation level such as parity, milk yield, cow diseases, and other disturbances, instead of cow or herd factors. Severe diarrhea between 3 and 7 mo of age was associated with 2.8-fold higher odds of VRCM compared with mild diarrhea during the same period, whereas the VRCM odds of calves with mild diarrhea were half that without diarrhea. The odds of VRCM had a predicted maximum at an estimated prepubertal growth rate of 859 g/d and increased with 10% for every 1-kg increase in concentrate ration during the last 2 mo before first calving. Costs of VRCM were estimated based on assumptions regarding veterinary service, extra labor, culling and herd replacement, discarded milk, and production loss depending on parity and lactation stage when VRCM was diagnosed. The total mean costs of VRCM were estimated to be $735 per lactation with a diagnosis of CM, $103 per lactation across all cows, or $95 per cow annually during lifetime. [ABSTRACT FROM AUTHOR]