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In the present study, relationships between the intestinal microbiota and innate immunity response, acute cryptosporidiosis, and weight gain in female dairy calves were investigated. A total of 112 calves born during a natural outbreak of cryptosporidiosis on one dairy farm was included in the study. Microbiota composition was analysed by means of 16S ribosomal RNA gene amplicon sequencing from faecal samples collected during the second week of life, while the status of Cryptosporidium spp. infection was determined using immunofluorescence. Serum samples from the second week of life were colourimetrically analysed for the following markers of acute inflammation: acute-phase proteins (serum amyloid A and haptoglobin) and pro-inflammatory cytokines (interleukin-1 beta, interleukin-6, and tumour necrosis factor-alpha). Statistical analyses were performed using random forest analysis, variance-partitioning, and negative binomial regression. The faecal microbiota of the two-week old calves was composed of the phyla Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria, and Actinobacteria (in order of decreasing abundance). Microbial diversity, measured in terms of the Shannon index, increased with the age of the calves and decreased if a high count of Cryptosporidium spp. oocysts was found in the faeces. Fusobacterium was positively associated with Cryptosporidium spp. oocyst count and serum amyloid A concentration. Peptostreptococcus was positively associated with haptoglobin and serum amyloid A concentrations, and negatively associated with average daily weight gain at 9 months of age. The markers of innate immunity, in combination with age, explained 6% of the microbial variation. These results suggest that some components of the intestinal microbiota may have a long-lasting negative effect on animal growth through the stimulation of the systemic innate immune response.

The core part of the mammal innate immune system is the acute-phase response (APR), during which acute-phase proteins (APP) are synthesized. Colostrum contains immunomodulating factors such as proinflammatory cytokines and APP in large quantities. We looked at proinflammatory cytokines [IL-1β, IL-6, and tumor necrosis factor-α (TNF-α)] and APP [serum amyloid A (SAA) and haptoglobin (Hp)] in colostrum and in calves' serum. The aim of this study was to evaluate the effects of colostrum on the calves' systemic APR and the associations of the calves' serum APR with short- and long-term weight gain (at the age of 1, 3, and 9 mo). A total of 143 female dairy calves were studied during their first 3 wk of life. The calves were separated from their mothers immediately after birth and bottle-fed 3 L of quality-controlled colostrum once within 2 h after birth. Serum samples were collected once a week during the first 3 wk of life (a total of 1-3 samples per calf). Mean sampling age (±standard deviation) was 4.3 (±2.0) d in the first week, 11.0 (±2.0) d in the second week, and 18.0 (±2.0) d in the third week. Linear regression models were used to study associations of colostrum APP and cytokine concentration with serum APR markers and for studying associations of colostrum and serum APR markers with calves' average daily weight gain (ADWG). Mixed linear regression models were used to compare serum concentrations of APR markers by study weeks. The colostrum IL-6 concentrations were positively associated with serum IL-6 in the first 3 wk of life. Colostrum IL-1β was positively associated with calves' serum IL-1β during the first week of life, and colostrum TNF-α was positively associated with calves' serum TNF-α during the first 2 wk of life. Serum IL-1β concentrations differed over the 3 wk, being the highest during the first week and the lowest during the second week. For IL-6, the concentration during the first week was the highest, and for TNF-α, a steady decline in the concentration was observed. Serum SAA concentrations were elevated during the first 2 wk of life and subsequently declined during the third week. Albumin concentrations were lowest in the first week, whereas Hp concentrations were highest during the second week. Serum concentrations of SAA, Hp, IL-6, and TNF-α during the second week were negatively associated with ADWG at 9 mo of age. The SAA concentrations during the third week of age had a negative association with 9-mo ADWG. Serum Hp concentrations in the third week were negatively associated with 3-mo ADWG. The results of our study suggest that colostrum cytokines influence calf serum cytokine concentrations. Thus, they influence the newborn calves' adaptation to the environment and the development of their immune system. Factors that activate an APR during the second and third week of life have a long-term influence on calves' development.

Background Culling is a major cost for dairy farms but also an essential part in managing herd productivity. This study aimed to identify the culling rates of Estonian dairy cows, identify the farmers’ stated reasons and risk factors for culling. This observational study used registry data of all cows from herds with ≥20 cow-years in 2013–2015. Cow lactation-level analyses included data of 86,373 primiparous cows from 409 herds and 177,561 lactations of 109,295 multiparous cows from 410 herds. Weibull proportional hazard regression models were used to identify risk factors for culling due to slaughter or death. Results The overall culling rate of Estonian dairy cows was 26.24 (95% CI 26.02; 26.46) per 100 cow-years. The most common reasons farmers stated for culling were feet/claw disorders (26.4%), udder disorders (22.6%), metabolic and digestive disorders (18.1%) and fertility problems (12.5%). Animal-level risk factors for culling were Holstein breed, older parity, lower milk yield breeding value, older age at first calving, longer previous calving interval, having assisted calving, stillbirth and birth of twins/triplets. Lower milk yield, somatic cell count over 200,000 cells/ml and fat/protein ratio over 1.5 at first test-milking after calving were associated with greater culling hazard during the lactation. Cows from larger herds, herds with decreasing size and higher milk yields had a higher culling probability. Conclusions This study emphasises the need for improved management of hoof health and prevention of mastitis and metabolic diseases. It is essential to ensure easy calving and good health of cows around calving in order to lower the culling hazard.

We aimed to evaluate the elimination of 4 different mastitis pathogens, Streptococcus agalactiae, Mycoplasma bovis, Staphylococcus aureus, and Streptococcus uberis, from infected udder quarters during the dry period using quantitative PCR. The second purpose of this study was to evaluate the association between milk haptoglobin (Hp) concentration and the presence of udder pathogens (Strep. agalactiae, Staph. aureus, M. bovis, and Strep. uberis) in udder quarter milk samples before and after dry period. Aseptic udder quarter milk samples (n = 1,001) were collected from 133 dairy cows at dry off and at the first milking after calving from 1 large dairy herd. Bacterial DNA of Strep. agalactiae, Staph. aureus, Strep. uberis, and M. bovis in the udder quarter milk samples was identified with commercial quantitative PCR analysis Mastitis 4B (DNA Diagnostic A/S, Risskov, Denmark). Milk Hp concentration (mg/L) was measured from udder quarter milk samples. The elimination rates during the dry period for M. bovis, Staph. aureus, Strep. agalactiae, and Strep. uberis were 86.7, 93.6, 96.2, and 100.0%, respectively. The new IMI rate was 3.0% for M. bovis, 2.9% for Staph. aureus, 2.4% for Strep. agalactiae, and 3.1% for Strep. uberis. The milk Hp concentration was significantly higher in udder quarter milk samples with blood and in samples positive for Strep. agalactiae at dry off and for Staph. aureus postcalving. Elevated milk Hp concentration was not associated with the presence of M. bovis in the udder quarter milk samples. In conclusion, elimination of Staph. aureus, Strep. agalactiae, and Strep. uberis during the dry period was high; the elimination of M. bovis from infected udder quarters was lower, but probably spontaneous. Additionally, milk Hp concentration may be used as a marker for udder inflammation when combined with the bacteriological results at dry off and postpartum.

We investigated the molecular epidemiology ofCryptosporidiumspp. in Estonia by testing fecal samples from 486 calves aged CryptosporidiumDNA. The parasites were identified and characterized by sequencing of the 18S rRNA gene and of the 60 kDa glycoprotein (gp60) gene. Moreover, using a questionnaire, we surveyed factors that could be relevant for animal-to-human and human-to-animal transmission ofCryptosporidiumspp. on the farms.Cryptosporidiumspp. were shed by 23% of the investigated calves and at least one shedding calf was found on 66% of the farms.Cryptosporidium parvumwas the most common species shed, whileC. bovisandC. ryanaewere also detected. More than half of the calves aged 8–14 days shedC. parvum. Nine previously describedC. parvumsubtypes (IIaA14G1R1, IIaA16G1R1, IIaA17G1R1, IIaA18G1R1, IIaA19G1R1, IIaA20G1R1, IIaA21G1R1, IIaA22G1R1 and IIaA16G2R1) and an apparently novel subtype IIlA21R2 were found. Calves from farms that reported spreading manure on fields during spring had 10 times higher odds to shedCryptosporidiumspp. in their feces than calves from farms that did not. Calves aged 8–14 days had higher odds to shed IIa18G1R1 as well as IIaA16G1R1 than younger calves.

Mortality (unassisted death and euthanasia) reflects the health and welfare state of the cows and is associated with undesirable financial consequences for the farmer. The objective of this retrospective observational study was to identify risk factors associated with on-farm mortality in dairy cows. Data for a study period between January 1, 2013 and December 31, 2015 were retrieved from the Estonian Agricultural Registers and Information Board and Estonian Livestock Performance Recording, Ltd. Cows from milk-recording herds with ≥20 cow-years were included. Analyses included data of 86,459 primiparous cows from 409 herds and 109,314 multiparous cows from 410 herds. Cows were followed from the day of calving until exit from the herd due to on-farm death or euthanasia (defined as mortality), slaughter, or selling. Associations between risk factors and mortality were assessed using Weibull proportional hazard models. The mortality rate (MR) was lower in primiparous cows (MR = 5.09 per 100 animal-years, 95% confidence interval [CI] 4.93; 5.26) compared to multiparous cows (MR = 8.28 per 100 animal-years, 95% CI 8.13; 8.44). The early lactation period was associated with greater mortality hazard. Animal-level factors significantly associated with higher mortality hazard in primiparous and multiparous cows were Holstein breed, older age at first calving, having an assisted calving or stillborn calf. In multiparous cows, male sex of the calf, birth of twins/triplets, older parity, longer previous inter-calving interval and milk somatic cell count over 200,000 cells/ml at the last test-milking of the previous lactation were associated with greater mortality hazard. Lower milk yield, somatic cell count over 200,000 cells/ml and fat/protein ratio over 1.5 at first test-milking were associated with greater mortality hazard during the lactation. Cow mortality risk was greater in larger herds, in herds with lower cow conception rate and poorer longevity of cows. Also, lower herd average milk fat/protein ratio and decreasing herd size (for multiparous cows) as well as Northeast region were herd level risk factors. This study outlines the importance of herd management and good health of the cows at dry-off and during early lactation and ensuring easy calving to reduce mortality of cows.

Cryptosporidium spp. infections in neonatal dairy calves can cause diarrhoea and, in rare cases, death. The infection is usually self-limiting, but halofuginone lactate (HL) can be used prophylactically. Calves (n = 144) in the study were born during a 2-month period on one farm. A total of 901 serum and 767 faecal samples were collected. Based on HL treatment, the calves were divided into 3 groups: I) not treated, II) treated incorrectly (treatment started > 48 h after birth, or lasted, Highlights • Acute phase response was affected by halofuginone lactate treatment. • Haptoglobin concentration was more affected than serum amyloid A by Cryptosporidium. • Gamma-glutamyltransferase activity after birth had a positive association with survival. • Halofuginone lactate treatment had a negative effect on weight gain.

Herd culling rates and longevity represent herd health and welfare status as well as farm economic performance. The contribution of endemic circulation of the main cattle pathogens to herd performance has not been previously analysed. The aim of this study was to estimate the herd prevalence of selected endemic bovine pathogens among large commercial dairy herds and to analyse their associations with herd culling rates and longevity. Bulk tank milk (BTM) samples and 10 heifer serum samples were collected from 120 Estonian dairy herds with at least 100 cows, between August 2019 and July 2020. All samples were tested for antibodies against bovine herpesvirus 1 (BHV-1), bovine viral diarrhoea virus (BVDV), bovine respiratory syncytial virus (BRSV), Mycoplasma bovis, Mycobacterium avium spp. paratuberculosis (MAP) and Salmonella Dublin using commercial ELISA. Data on herd size, milk yield, culling rate (CR) and mean age of the culled cows (MAofCC) were collected from the Estonian Livestock Performance Recording Ltd. The apparent herd and animal prevalences were calculated, and linear regression models were used to identify associations between the herd status of six tested pathogens and CR and MAofCC. The herd seroprevalences for antibodies based on BTM and heifer serum sample testing were BHV-1 56.7 % (95 % CI 47.3; 65.7), Mycoplasma bovis 48.3 % (95 % CI 39.1; 57.6), MAP 2.5 % (95 % CI 0.5; 7.1) and S. Dublin 24.2 % (95 % CI 16.8; 32.8) in all tested herds. Excluding vaccinated herds, herds prevalence for BVDV was 27.0 % (95 % CI 19.0; 36.3) and for BRSV 94.7 % (95 % CI 88.1; 98.3). Herd seropositive status for BRSV was associated with lower MAofCC, and herds with BSRV-seropositive youngstock had increased CR. Herds with positive BTM test results for S. Dublin culled cows at an older average age (Coef = 3.79 months, 95 % CI 0.52; 7.07, p = 0.023). MAP-positive herds had somewhat lower herd MAofCC (Coef = -6.18 months, 95 % CI -12.98; 0.63, p = 0.075). There was also a tendency of BVDV-negative herds to have a lower CR than BVDV-positive herds (Coef = -3.03 %, 95 % CI -6.54; 0.49, p = 0.090), and vaccination against BVDV tended to be protective against high CR (Coef = -6.26 %, 95 % CI -12.61; 0.09, p = 0.053 compared to infected herds). This study shows that Estonian large-scale dairy herds are endemically infected with several important cattle pathogens. Most of the studied pathogens influence longevity and culling rates, thus entailing health and economic consequences.

Efficient dairy-beef production relies on good quality of purchased calves, defined by breed, health, and growth characteristics. Several management factors, such as commingling of calves and large group size, predispose calves to diseases. Acute phase proteins are sensitive detectors of calf diseases. We studied the associations between group size, serum acute phase proteins, immunoglobulin G (IgG), calf morbidity and growth of dairy-beef calves in a random field trial in a calf-rearing unit in Finland. The randomized trial was carried out at a calf rearing unit, where approximately 80 dairy or crossbred calves were allocated either into a single group of 40 calves or into four groups of 10 on arrival at the calf-rearing unit (at age 24.1 SD +/- 9.2 days). The study was carried out on 6 arrival batches: 476 calves. Calves were clinically examined and blood sampled on arrival (day 0), and haptoglobin (Hp), serum amyloid A (SAA), albumin and IgG were determined. Calves were weighed on arrival (day 0, average age 24.1 days), at the end of the milk feed period (day 49), at approximately 200 days of age and at slaughter (carcass weight) at 15-18 months of age. During the rearing calves were observed by the farm workers and treated, if necessary, according to pre-determined instructions of the veterinary surgeon. All NSAID and antimicrobial treatments were recorded and used as morbidity indicators in statistical analysis. There were no differences in the numbers of antimicrobial treatments or growth among the groups. The majority (84.1%) of antimicrobial treatments were used against respiratory tract infections. Higher concentrations of albumin and IgG on arrival extended the time before the first and the second antimicrobial treatments. Complex relationships between group size, morbidity, concentrations of serum acute phase proteins and IgG at arrival, and growth of calves were explored. Group size of 10 calves did not protect calves from respiratory tract infections, when the small groups were sharing the air space with a large group. An increased SAA concentration on arrival was associated with poorer average daily gain at two rearing periods and with lower carcass weight at slaughter. Serum proteins could be valuable health indicators for purchased calves because they have numerous and variable associations with health and growth. The mechanisms that connect increased SAA concentration and poorer average daily gain over the long term remain unclear.

Highlights • We tested serum amyloid A and haptoglobin serum levels in Eimeria zuernii infections. • Haptoglobin levels rose during clinical eimeriosis. • A rise in serum amyloid A and haptoglobin correlated well with weight loss. • Acute phase proteins are important in the immunological mechanisms of eimeriosis., Acute phase proteins (APPs) have been demonstrated to be useful in evaluating general health stress and diseases in cattle. Serum amyloid A (SAA) and haptoglobin (Hp) are APPs that are produced during inflammation, and likely play a role in host immunological defence against Eimeria infection and the associated intestinal tissue damage. We investigated the involvement of SAA and HP in an experimental study, including three groups of calves: a control group (group 0, n = 11), and two groups infected with either 150,000 or 250,000 Eimeria zuernii oocysts (group 1 (n = 11) and group 2 (n = 12), respectively). The calves were monitored for 28 days and data was collected on oocyst excretion, faecal score, animal weight, and SAA and Hp serum concentrations. Generalized linear mixed models showed that the clinical symptoms, indicated by an increase in the number of oocysts in the faeces and severe diarrhoea, manifested at patency for group 1 and 2. Serum Hp and SAA levels also increased during this period. Hp appeared to be a more sensitive marker than SAA, and differences between groups 1 and 2 were observed only for Hp. Linear regression models showed a negative association between weight gain and Hp concentrations, calculated as the area under the curve (AUC) during the overall experimental period and the patency period. A similar result was seen for SAA only during the patency period. This result supports the assumption that reduced weight gain due to E. zuernii infection is an immunologically driven process that involves an increase in APPs. A random intercept regression model of oocyst shedding groups showed that calves shedding 1–500 oocysts had reduced concentrations of Hp, indicating that a different immunological reaction occurs during mild shedding of E. zuernii oocysts than during more intensive shedding. A similar model was used to examine associations between faecal scores and Hp concentrations for each group. Group 2 calves with haemorrhagic diarrhoea displayed higher Hp levels than calves in that group with lower faecal scores, which may be in response to an increased demand for Hp in the repair process as a result of haemolysis. APPs seem to play an important role in determining the course of E. zuernii infection in calves, which may enhance our understanding of the immunological reaction and development of this disease.

Highlights • Multiple intestinal pathogen species were present in both healthy and diarrheic calves. • Decreased haptoglobin concentrations were associated with weak signs of eimeriosis. • Increased haptoglobin and fibrinogen concentrations were associated with respiratory tract infection and umbilical infection., In this study, the association between Eimeria spp. related signs and innate immune response in dairy calves was examined. Calves (n = 100) aged 15–60 days were clinically examined and faecal samples, blood samples and deep nasopharyngeal swabs obtained. The samples were analysed for intestinal pathogens, acute phase proteins and WBC count, and respiratory tract pathogens, respectively. Diarrhoea was diagnosed in 32.6% (23.3–43.0%, 95% CI) of calves. An association between the pathogenic Eimeria spp. and diarrhoea was detected by multiple correspondence analysis. Eimeria related signs (diarrhoea, presence of pathogenic species and total oocyst count) were combined resulting a four level variable. Calves with weak signs of eimeriosis had decreased haptoglobin concentrations (p = 0.02) and increased fibrinogen concentrations (p = 0.048) compared to no signs. Increased haptoglobin and fibrinogen concentrations were associated with respiratory tract infection and umbilical infection. Serum amyloid A and WBC counts showed no association with signs of eimeriosis or clinical diagnoses.

This longitudinal observational study was conducted to investigate the spontaneous effect of Giardia and Cryptosporidium infections on acute phase response (APR) in reindeer calves (Rangifer tarandus tarandus) in Finnish Lapland. Serum (n = 609) and faecal samples (n = 366) were collected from 54 reindeer calves aged zero to 33 days. The samples were analysed for Giardia, Cryptosporidium, acute phase proteins (APP) and gamma-globulins. Linear regression models were used to investigate associations of early Giardia infection (before 12 days of life) with the response of APPs and acquiring of passive immunity. Giardia was detected in 100% and Cryptosporidium in 23% of calves. There was a negative association between early Giardia infection and gamma-globulin concentrations (p = 0.032) and a positive association with serum amyloid A (SAA) concentrations (p = 0.042). The results suggest a protective effect of colostrum against Giardia infection and that early infection may induce activation of APR.

Bovine herpesvirus 1 (BHV-1) causes infectious bovine rhinotracheitis (IBR), infectious pustular vulvovaginitis, abortion and balanoposthitis, as well as neurological and systemic disease in cattle. The virus is endemic in cattle populations worldwide although in Europe six countries and several regions in other countries have achieved 'IBR-free' status by implementing control measures. According to European Union (EU) directives, all member states must comply with specific requirements related to BHV-1 infection status in semen and embryos. The requirement that 'IBR-free' states restrict the importation of cattle from endemically infected regions has motivated several European countries to instigate disease eradication programmes. Despite such control measures within the EU, outbreaks of IBR persist in 'IBR-free' states contiguous with infected countries. This review presents a summary of recent research on the epidemiology of BHV-1, highlights the control measures and surveillance systems in place, and discusses the challenges facing eradication schemes.

High on-farm mortality is associated with lower financial return of production and poor animal health and welfare. Understanding the reasons for on-farm mortality and related risk factors allows focus on specific prevention measures. This retrospective cohort study used cattle registry data from the years 2013 and 2014, collected from cattle from all Estonian cow-calf beef herds. The dataset contained 78,605 animal records from 1321 farms in total. Including unassisted deaths and euthanasia (2199 in total) the on-farm mortality rate was 2.14 per 100 animal-years. Across all age groups of both sexes the mortality rate (MR) was highest for bull calves up to three months old (MR= 7.78 per 100 animal-years, 95% CI 6.97; 8.68) followed by that for heifer calves (MR= 6.21 per 100 animal-years, 95% CI 5.49; 7.02). For female cattle the mortality risk declined after three months of age but increased again among animals over 18 months.The reason for death stated by the farmers was analysed for cattle under animal performance testing. Other/unknown reasons, trauma and accidents, as well as metabolic and digestive disorders, formed the three most commonly reported reasons for death in cattle of all age groups.Weibull proportional hazard models with farm frailty effects were applied in three age categories (calves up to three months, youngstock from three to 18 months and cattle aged over 18 months) to identify factors associated with the risk of mortality. Male sex was associated with increased risk of mortality in cattle up to 18 months of age. No difference between breeds was found for cattle up to 18 months of age. Beef cattle breeds rarely represented or dairy breeds (breed category 'Other') had the highest mortality hazard (HR= 1.41, 95% CI 1.11; 1.78) compared to Hereford. The hazard of mortality generally increased with herd size for calves, young stock and older bulls. In female cattle over 18 months of age there was no difference in mortality hazard over herd size categories. Herd location was controlled in the models and regional differences in mortality hazard were found. Common to all age groups, calving season was associated with increased risk of mortality. (C) 2016 Elsevier B.V. All rights reserved.

Bovine acute phase proteins (APPs), lipopolysaccharide binding protein (LBP), serum amyloid A (SAA), haptoglobin (Hp) and alpha(1)-acid glycoprotein (AGP) were evaluated as inflammatory markers during an outbreak of bovine respiratory disease (BRD) caused by bovine respiratory syncytial virus (BRSV). Calves (n = 10) presented mild to moderate signs of respiratory disease. Secondary bacterial infections, Pasteurella multocida and Mycoplasma dispar as major species, were detected in tracheobronchial lavage samples. Concentrations of SAA and LBP increased at week 1 had the highest values at week 3 and decreased at week 4 of outbreak. Some calves had high Hp concentrations at week 3, but AGP concentrations did not rise during respiratory disease. Higher SAA, LBP and Hp concentrations at a later stage of BRD (week 3) were associated with the low BRSV-specific IgG(1) production, suggesting that these calves had enhanced inflammatory response to the secondary bacterial infection. In conclusion, APPs (especially SAA and LBP) are sensitive markers of respiratory infection, and they may be useful to explore host response to the respiratory infections in clinical research.

The objectives of this study were to reassess the herd level and within-herd prevalence of bovine herpesvirus 1 (BHV1) infection in Estonian dairy cattle, estimate the sensitivity and specificity of the enzyme-linked immunosorbent assay (ELISA) for bulk tank milk (BTM) testing and determine the risk factors related to high prevalence of the infection in herds. To estimate the herd prevalence, BTM samples from each of the 1,205 herds that sell milk to dairy companies were analysed for BHV1 antibodies. One hundred and three herds with known BHV1 infection status were selected to estimate within-herd prevalence and to calculate the sensitivity and specificity of BTM ELISA. In these herds serum samples were collected from cows and youngstock, together with BTM samples. A commercial blocking ELISA test was used to analyse samples for antibodies against BHV1. A questionnaire was completed to collect herd data. The sensitivity and specificity of the BTM ELISA were 76.5% and 97.2%, respectively, and the true herd prevalence of BHV1 was calculated to be 22.0%. The herd prevalence increased significantly with herd size, being 3.4% in the smallest category (less than 20 cows) and 85.7% in herds of size over 400. The mean within-herd prevalence was 37.8% (range 1-100, median 31.5). The mean within-herd prevalence increased with herd size. Data from 59 infected herds was used to determine the risk factors associated with high within-herd prevalence (>50%) of BHV1, using logistic regression analysis. As, in some infected herds, the youngstock were uninfected, risk factors for the presence of BHV1 among youngstock from 6 months until calving were analysed. The results indicate the importance of iatrogenic spread of the virus, since the overall within-herd prevalence was higher in those herds in which a veterinarian was an employee of the farm and an inseminator worked only for the particular farm. The presence of bovine viral diarrhoea virus (BVDV) in a herd was associated with a higher prevalence of BHV1.

Eighty-four calves with respiratory disease from 18 herds in different parts of Finland were chosen for a study evaluating the capacity of different respiratory pathogens to cause changes in different acute phase protein concentrations, white blood cell (WBC) count and clinical signs. The selected acute phase proteins were fibrinogen, haptoglobin, serum amyloid-A, lipopolysaccharide binding protein and alpha1-acid glycoprotein. From each calf, a paired blood sample was obtained for serological studies of bovine parainfluenza virus-3, bovine respiratory syncytial virus, bovine coronavirus, bovine adenovirus-3 and bovine adenovirus-7. Tracheobronchial lavage was performed to detect bacteria and mycoplasma. Isolation of Pasteurella multocida was associated with increased concentrations of all tested acute phase proteins. For other pathogens, no significant relationships were observed. No association was present between viral or bacterial findings and WBC count.

The aim of this study was to estimate the effect of the bovine herpesvirus 1 (BHV-1) vaccination on herd health and production in BHV-1 infected Estonian dairy cattle herds. Seven herds vaccinated with inactivated gE-negative BHV-1 marker vaccines and seven matched non-vaccinated herds were selected. In vaccinated herds the calving interval was on average 7.01 days shorter compared to that in the non-vaccinated herds (coef = −7.01, 95% CI = −11.98, −2.03, p = 0.008) during the study period (2007–2012). In non-vaccinated herds the insemination index had an increasing trend (coef(log scale) = 0.03, 95% CI = −0.003, 0.06, p = 0.054) and the first service conception rate decreased (coef = −2.19, 95% CI = −3.91, −0.47, p = 0.015), whereas no significant changes occurred in vaccinated herds. Average yearly milk yield per cow increased (coef = 145.30, 95% CI = −6.11, 296.71, p = 0.065) and length of the dry period decreased in BHV-1 vaccinated herds (coef(log scale) = −0.02, 95% CI = −0.04, 0.004, p = 0.056) compared to non-vaccinated herds during the study years. Youngstock and the cow culling rate due to respiratory disease was significantly lower in vaccinated herds compared to non-vaccinated herds (coef = −0.29, 95% CI = −0.47, −0.11, p = 0.003 and coef = −0.15, 95% CI = −0.29, −0.007, p = 0.043, respectively). These results suggest that vaccination against BHV-1 is associated with herd health and productivity.

Positive acute phase proteins (APP) are proteins whose concentration in blood increases greatly during the acute phase of inflammation as a systemic response to a local initiation. Although the acute phase reaction cannot help to localise the lesion, changes in APP concentrations can be used to assess severity of the inflammatory disease or to differentiate between acute and chronic inflammation (Horadagoda and others 1999). The importance of APPs as inflammatory markers in veterinary medicine is gradually increasing (Eckersall and Bell 2010), but their clinical use in bovine medicine has been limited partly due to lack of reference values. An increase in APP concentrations during respiratory infections in calves is well established (Ganheim and others 2003, Nikunen and others 2007, Orro and others 2011), and acute-phase response in calves with diarrhoea, umbilical inflammation and other inflammatory diseases has also been examined (Ganheim and others 2007, Tothova and others 2012). This study aimed to establish reference values for fibrinogen (Fb), haptoglobin (Hp) and serum amyloid A (SAA) for young calves. The accuracy of these reference values was also tested in the diagnosis of inflammation severity by using calves with umbilical diseases, as the preliminary umbilical disease diagnosis and the severity of inflammation can be reliably confirmed in surgery. Blood samples from 120 healthy dairy calves were collected from a representative sample of Finnish dairy farms, located in the vicinity of the Production Animal Hospital, University of Helsinki, in southern Finland. The calves were clinically examined for signs of disease and their rectal temperature was also measured. They were included in the study if they showed no signs of illness and their rectal temperature was

Bovine herpesvirus type 1 (BHV-1) is an important bovine pathogen, exacerbating poor health and the productivity of cattle. The aims of this study were to detect the efficacy of vaccination programmes in lowering the seroprevalence of BHV-1 gE within the dairy herd and to follow the dynamics of the infection in non-vaccinated herds with uninfected heifers. A two-year longitudinal study was carried out on seven herds that were vaccinated, and in five herds with uninfected heifers without applying a control programme. After the start of the vaccination programme, calves born remained free from the virus. However, in one herd, 7 per cent (95 per cent CI 2 to 18) of these animals showed antibodies to BHV-1 two years after the first vaccination. A decline in BHV-1 antibody prevalence was found in vaccinating herds. Among the five herds not under the control programme, one experienced active virus spread, although one herd experienced self-clearance of the virus. In the herds with high BHV-1 prevalence, vaccinating all cattle from three months of age twice a year with a commercial inactivated marker vaccine efficiently protected offspring from becoming infected, and lowered the prevalence of BHV-1 within the herd. A small proportion of herds may experience self-clearance of the virus.

Cows infected with the tissue parasite Neospora caninum (Nc) are more likely to abort or give birth to calves with neurological disorders. The known infection routes are transplacentally and by consumption of oocysts shed by the definitive host, the dog. It has been hypothesised, that dormant stages of persistent Nc infection may be reactivated by immunosuppression mechanisms such as pathogenic invasions as bovine herpes virus 1 (BHV1) and bovine virus diarrhoea virus (BVDV). The study was set to give the first prevalence data on Nc from Estonian dairy herds in both animal as well as herd level. In addition, association between herd size and Nc, and association of Nc with abortion incidence (Ab), stillbirth incidence (Sb), insemination index (II), and calving interval (CaI) in the presence of BHV1 and BVDV was studied. Blood samples from 1973 animals from 100 herds were collected in 2006–2008, and 320 bulk tank milk (BTM) samples were collected in 2007. Antibodies against Nc was found in 2.5 ± 0.4% (95% CI) of the animals and at least one positive animal was found in 37.0 ± 4.7% (95% CI) of the herds. In addition, Nc antibodies were detected in 16.3 ± 2.0% (95% CI) of the tested BTM. Large herds (≥200 animals) were less likely to have seropositive animals for Nc. Logistic regression models showed that herds with more than one animal seropositive for Nc had significantly higher odds ratio of abortion incidence (OR: 11.92, 1.18–120.18 95% CI, p = 0.036) and tendency of having more stillbirths (OR: 5.52, 0.87–35.02 95% CI, p = 0.07). On the other hand one Nc seropostive cow in the herd was associated with lower odds ratio (OR: 0.22, 0.05–0.91 95% CI, p = 0.04) of higher calving intervals. Estonian prevalence results reflect observations in the region. No evidence was found of the pathogens were affecting fertility variables through interactions but independently BHV1 and Nc had an impact on the abortion.

Background The aim of this study was to detect the associations between bovine herpesvirus 1 (BHV-1) status of a herd and respiratory disease (BRD) occurrence and reproductive performance in pregnant heifers and cows. The association between management-related factors and higher BRD occurrence was also estimated. Methods Serum samples, collected from cows and youngstock from 103 dairy cattle herds, were analyzed for antibodies against BHV-1, bovine respiratory syncytial virus (BRSV), bovine viral diarrhoea virus (BVDV), and Mycoplasma bovis. A questionnaire was used to collect data concerning herd management factors and reproductive performance, as well as the occurrence of clinical signs of respiratory disease in the last two years, as evaluated by the veterinarian or farm manager. Multiple correspondence analysis (MCA) and logistic regression analysis were performed to identify and quantify the risk factors. Results A low to moderate prevalence (1-49%) of BRSV antibodies among youngstock was associated with a high occurrence of respiratory disease (OR = 6.2, p = 0.010) in cows and in-calf heifers. Employees of the farm may participate in the spread of such disease. Larger herd size, loose-housing of cows, housing youngstock separately from cows until pregnancy, and purchasing new animals were factors possibly related to a high occurrence of respiratory disease symptoms in pregnant heifers and cows. The highest risk of abortions (> 1.3%) and increased insemination index (number of inseminations per pregnancy) (> 1.9) occurred in herds with a moderate prevalence of BHV-1 antibodies (1-49%) in cows. Conclusions BHV-1 was not associated with acute respiratory disease in adult dairy cattle, however was significantly related to reproductive performance. BRSV possesses the main role in respiratory disease complex in adult dairy cattle.

The associations between herd bovine herpesvirus 1 (BHV-1) seroprevalence, along with other infectious and farm management factors with bovine respiratory disease (BRD) in dairy calves and heifers, were investigated. Serum samples from 103 dairy cattle herds were analyzed for antibodies against BHV-1, bovine respiratory syncytial virus (BRSV), bovine viral diarrhea virus (BVDV), and Mycoplasma bovis (M. bovis). A questionnaire was used to record herd management practices. A high occurrence of respiratory disease in unweaned calves was associated with low to moderate and high prevalence of BHV-1 among cows (OR = 14.8, p = 0.005 and OR = 19.2, p = 0.002, respectively) and positive BVDV status of a herd (OR = 5.1, p = 0.02). The presence of BVDV in a herd was related to a high incidence of respiratory disease in heifers 3–16 months old (OR = 4.3, p = 0.027). Based on the results of multiple correspondence analysis, holding youngstock separately from cows until pregnancy, introducing new animals and the activities of on-farm employees may contribute to a higher incidence of BRD.

HOOF health is an important animal welfare and economic issue for dairy producers. Many studies have shown how lameness, usually due to hoof lesions ([Murray and others 1996][1]), can affect ovarian activity, udder health, milk yield and the risk of culling ([Green and others 2002][2], [Hultgren and

Six transgenic cows producing recombinant human lactoferrin (rhLf) in their milk and five normal cows at the same lactation stage were experimentally infected with Staphylococcus chromogenes to study the effect of a high concentration of lactoferrin in milk. Coagulase-negative staphylococci such as S. chromogenes have become very common as agents causing mild or subclinical mastitis. All transgenic cows became infected but showed no clinical signs, unlike the control cows, which developed mild clinical mastitis. Transgenic cows eliminated bacteria faster from the quarters than did the controls. Local clinical signs were milder, and the inflammatory reaction assessed by NAGase activity in the milk and by the concentration of milk amyloid A was lower in the transgenic cows. The mild response probably reflected the rapid elimination of bacteria. The milk concentration of rhLf remained constant throughout the study period, but the total concentration of bovine lactoferrin in the milk peaked in both groups at 46 h post-challenge. Three cows, all in the control group, exhibited systemic acute phase response as increased concentrations of serum amyloid A in the blood circulation. Transgenic cows with a high concentration of human lactoferrin in their milk seemed to be protected from clinical disease and from prolonged inflammatory reaction, but not from experimental intramammary infection induced by S. chromogenes .

An experimental infection model was developed to study host response to intramammary infection in cows caused by Staphylococcus chromogenes. CNS intramammary infections have become very common in modern dairy herds, and they can remain persistent in the mammary gland. More information would be needed about the pathophysiology of CNS mastitis, and an experimental mastitis model is a means for this research. Six primiparous Holstein-Friesian cows were challenged with S. chromogenes 4 weeks after calving. One udder quarter of each cow was inoculated with 2.1 x 10(6)cfu of S. chromogenes. All cows became infected and clinical signs were mild. Milk production of the challenged quarter decreased on average by 16.3% during 7 days post-challenge. Cows eliminated bacteria in a few days, except for one cow which developed persistent mastitis. Milk indicators of inflammation, SCC and N-acetyl-beta-D-glucosaminidase (NAGase) returned to normal within a week. Milk NAGase activity increased moderately, which reflects minor tissue damage in the udder. Concentrations of serum amyloid A (SAA) and milk amyloid A (MAA) were both elevated at 12h PC. MAA was affected by the milking times, and was at its highest before the morning milking. In our experimental model, systemic acute phase protein response with SAA occurred as an on-off type reaction. In conclusion, this experimental model could be used to study host response in CNS mastitis caused by the main CNS species and also for comparison of the host response in a mild intramammary infection and in more severe mastitis models.

International audience; Age-dependent changes in blood concentrations of four bovine acute phase proteins (APPs), serum amyloid A (SAA), lipopolysaccharide binding protein (LBP), haptoglobin (Hp) and alpha1-acid glycoprotein (AGP), were examined using two groups of newborn dairy calves. APP concentrations were monitored for either 3 weeks (Group A, n = 13) or 2 months (Group B, n = 13) after birth. Blood was collected at day 0–1 (Group A only), day 3 and then once or twice weekly until the end of the study. The possible transfer of colostral SAA as a source of SAA in the offspring was investigated by determining SAA isoforms in the serum of calves and in colostrum of their dams. Serum concentrations of all four APPs were high after birth, and concentrations showed a gradual decrease during the first 3 weeks of life. The lowest concentrations were at 21 days of age, after which concentrations stabilized. The calves synthesized adult SAA isotypes, and circulating SAA was not derived from colostrum. The results indicated that post-partum elevation of APPs is associated with the birth process and/or factors in colostrum and not necessarily with disease-related processes. This stresses the importance of considering a calf’s age when interpreting APP concentrations in serum.

This is the first study describing an experimental mastitis model using transgenic cows expressing recombinant human lactoferrin (rhLf) in their milk. The aim of the study was to investigate the concentrations in milk and protective effects of bovine and recombinant human lactoferrin in experimental Escherichia coli mastitis. Experimental intramammary infection was induced in one udder quarter of seven first-lactating rhLf-transgenic cows and six normal cows, using an E. coli strain isolated from cows with clinical mastitis and known to be susceptible to Lf in vitro. Clinical signs were recorded during the experimental period, concentrations of human and bovine Lf and indicators of inflammation and bacterial counts were determined for milk, and concentrations of acute-phase proteins and tumor necrosis factor alpha were determined for sera and milk. Serum cortisol and blood hematological and biochemical parameters were also determined. Expression levels of rhLf in the milk of transgenic cows remained constant throughout the experiment (mean, 2.9 mg/ml). The high Lf concentrations in the milk of transgenic cows did not protect them from intramammary infection. All cows became infected and developed clinical mastitis. The rhLf-transgenic cows showed milder systemic signs and lower serum cortisol and haptoglobin concentrations than did controls. This may be explained by lipopolysaccharide-neutralizing and immunomodulatory effects of the high Lf concentrations in their milk. However, Lf does not seem to be a very efficient protein for genetic engineering to enhance the mastitis resistance of dairy cows.

The concentrations of haptoglobin (Hp) and serum amyloid A (SAA) and the activity of N-acetyl-β-D-glucosaminidase (NAGase) in milk from 234 cows with spontaneous mastitis caused by different pathogens were measured to assess whether they corresponded with the clinical signs of mastitis and whether there were any differences between pathogens. Ninety-eight of the cows had clinical mastitis and 136 had subclinical mastitis. There were statistically significant positive correlations between the concentrations of SAA and Hp and the activity of NAGase. Significant differences in the concentrations of acute phase proteins and NAGase activity were found in milk from cows with mastitis caused by different pathogens. The highest concentrations of Hp and NAGase were found in cases of mastitis caused by Escherichia coli and Arcanobacterium pyogenes, and the lowest concentrations were from cases of mastitis caused by coagulase-negative staphylococci. Very low SAA concentrations were found in milk from the cases caused by A pyogenes, in contrast to cases caused by other major mastitis pathogens. The median concentration of SAA was over 10 times higher in cases of mastitis caused by E coli than in mastitis caused by other pathogens. There were significant differences in the mean Hp concentration and NAGase activity between clinical and subclinical mastitis. In approximately one-third of the samples, the Hp concentration was below the detection limit, potentially compromising the use of Hp as a mastitis marker.

Background The aim of the study was to test the effect of two treatments in cases of acute puerperal metritis (APM) and clinical metritis (CM). Methods Cows with APM and CM (n = 40)) were matched according to plasma fibrinogen levels (Fb) into three groups. Two negative control groups D (n = 11) and E (n = 17) were composed of healthy cows. The proportion of animals with APM and CM was similar within the groups. Treatment was started on the 3rd day postpartum (PP). In group A (n = 15), intramuscular (i.m.) administration of ceftiofur was used for five days in combination with flunixin for three days. Group B (n = 15) received i.m. administration of ceftiofur for five days followed by two injections of prostaglandin F2α, with an interval of 8 h, on the 8th day PP. Group C (n = 10) served as a control group with no treatment. The general health status, body temperature (BT) and vaginal discharge were evaluated daily. Endometrial biopsies for bacteriology were taken once a week for seven weeks PP. Blood samples for the analysis of acute phase proteins were collected once a week for six weeks PP. Samples for progesterone analysis were taken twice a week for seven weeks PP. Fertility performance data were recorded. Results The area under the curve of BT was higher in group B than in group D cows (P Conclusions Regardless of more severe uterine inflammation found in animals from group B, these cows showed the same fertility parameters as healthy animals.

Background The goal of this study was to estimate the distribution of udder pathogens and their antibiotic resistance in Estonia during the years 2007-2009. Methods The bacteriological findings reported in this study originate from quarter milk samples collected from cows on Estonian dairy farms that had clinical or subclinical mastitis. The samples were submitted by local veterinarians to the Estonian Veterinary and Food Laboratory during 2007-2009. Milk samples were examined by conventional bacteriology. In vitro antimicrobial susceptibility testing was performed with the disc diffusion test. Logistic regression with a random herd effect to control for clustering was used for statistical analysis. Results During the study period, 3058 clinical mastitis samples from 190 farms and 5146 subclinical mastitis samples from 274 farms were investigated. Positive results were found in 57% of the samples (4680 out of 8204), and the proportion did not differ according to year (p > 0.05). The proportion of bacteriologically negative samples was 22.3% and that of mixed growth was 20.6%. Streptococcus uberis (Str. uberis) was the bacterium isolated most frequently (18.4%) from cases of clinical mastitis, followed by Escherichia coli (E. coli) (15.9%) and Streptococcus agalactiae (Str. agalactiae) (11.9%). The bacteria that caused subclinical mastitis were mainly Staphylococcus aureus (S. aureus) (20%) and coagulase-negative staphylococci (CNS) (15.4%). The probability of isolating S. aureus from milk samples was significantly higher on farms that had fewer than 30 cows, when compared with farms that had more than 100 cows (p < 0.005). A significantly higher risk of Str. agalactiae infection was found on farms with more than 600 cows (p = 0.034) compared with smaller farms. The proportion of S. aureus and CNS isolates that were resistant to penicillin was 61.4% and 38.5%, respectively. Among the E. coli isolates, ampicillin, streptomycin and tetracycline resistance were observed in 24.3%, 15.6% and 13.5%, respectively. Conclusions This study showed that the main pathogens associated with clinical mastitis were Str. uberis and E. coli. Subclinical mastitis was caused mainly by S. aureus and CNS. The number of S. aureus and Str. agalactiae isolates depended on herd size. Antimicrobial resistance was highly prevalent, especially penicillin resistance in S. aureus and CNS.

Background The main objective of this study was to estimate the effect of supplementation with Saccaromyces cerevisiae (SC) (Yea-Sacc® 1026) on milk production, metabolic parameters and the resumption of ovarian activity in early lactation dairy cows. Methods The experiment was conducted during 2005/2006 in a commercial tied-house farm with an average of 200 milking Estonian Holstein Friesian cows. The late pregnant multiparous cows (n = 46) were randomly divided into two groups; one group received 10 g yeast culture from two weeks before to 14 weeks after calving. The groups were fed a total mixed ration with silages and concentrates. Milk recording data and blood samples for plasma metabolites were taken. Resumption of luteal activity was determined using milk progesterone (P4) measurements. Uterine bacteriology and ovarian ultrasonography (US) were performed and body condition scores (BCS) and clinical disease occurrences were recorded. For analysis, the statistical software Stata 9.2 and R were used to compute Cox proportional hazard and linear mixed models. Results The average milk production per cow did not differ between the groups (32.7 ± 6.4 vs 30.7 ± 5.3 kg/day in the SC and control groups respectively), but the production of milk fat (P < 0.001) and milk protein (P < 0.001) were higher in the SC group. There was no effect of treatment on BCS. The analysis of energy-related metabolites in early lactation showed no significant differences between the groups. In both groups higher levels of β-hydroxybutyrate (BHB) appeared from days 14 to 28 after parturition and the concentration of non-esterfied fatty acid (NEFA) was higher from days 1–7 post partum (PP). According to US and P4 results, all cows in both groups ovulated during the experimental period. The resumption of ovarian activity (first ovulations) and time required for elimination of bacteria from the uterus did not differ between the groups. Conclusion Supplementation with SC had an effect on milk protein and fat production, but did not influence the milk yield. No effects on PP metabolic status, bacterial elimination from the uterus nor the resumption of ovarian activity were found.