Longitudinal study of Chlamydia pecorum in a healthy Swiss cattle population.

Chlamydia pecorum is a globally endemic livestock pathogen but prevalence data from Switzerland has so far been limited. The present longitudinal study aimed to get an insight into the C. pecorum prevalence in Swiss cattle and investigated infection dynamics. The study population consisted of a bovine herd (n = 308) located on a farm in the north-eastern part of Switzerland. The herd comprised dairy cows, beef cattle and calves all sampled up to five times over a one-year period. At each sampling timepoint, rectal and conjunctival swabs were collected resulting in 782 samples per sampled area (total n = 1564). Chlamydiaceae screening was performed initially, followed by C. pecorum-specific real-time qPCR on all samples. For C. pecorum-positive samples, bacterial loads were determined. In this study, C. pecorum was the only chlamydial species found. Animal prevalences were determined to be 5.2-11.4%, 38.1-61.5% and 55-100% in dairy cows, beef cattle and calves, respectively. In all categories, the number of C. pecorum-positive samples was higher in conjunctival (n = 151) compared to rectal samples (n = 65), however, the average rectal load was higher. At a younger age, the chlamydial prevalence and the mean bacterial loads were significantly higher. Of all sampled bovines, only 9.4% (29/308) were high shedders (number of copies per µl >1,000). Calves, which tested positive multiple times, either failed to eliminate the pathogen between sampling timepoints or were reinfected, whereas dairy cows were mostly only positive at one timepoint. In conclusion, C. pecorum was found in healthy Swiss cattle. Our observations suggested that infection takes place at an early age and immunity might develop over time. Although the gastrointestinal tract is supposed to be the main infection site, C. pecorum was not present in rectal samples from dairy cows.

[Relationship between metabolic profiles in herd health and 4 scoring systems used in dairy herd health programs: Statistical analysis with an additive Bayesian network]. / Zusammenhänge zwischen metabolischen Profilen und 4 Bestandsbetreuung-Scores bei Milchkühen: Statistische Analyse anhand eines additiven Bayesian Netzwerkes.

OBJECTIVE: The aim of the present study was to describe the relationship between the biochemical variables used in metabolic profiles and various scores commonly used in herd health management of dairy cows. The Bayesian network was used to determine the relationship between metabolic blood profiles and the scores for body condition (BC), rumen fill (RF), faecal consistency (FC) and undigested fraction (UF) on a herd basis. MATERIALS AND METHODS: In each of 10 dairy herds, blood was collected from a minimum of ten lactating cows for biochemical analysis and generation of metabolic profiles. This yielded a total of 106 blood samples. The biochemical results in the metabolic profiles were stratified by days in milk and compared with the scores of BC, RF, FC and UF using an additive Bayesian network. RESULTS: The blood glucose concentration directly affected the FC score. The was an effect of beta-hydroxybutyrate (BHB) on free fatty acids (FFS). An additional effect of BHB on the concentration of urea was detected. The concentration of urea affected the concentration of phosphorus and GOT activity. Urea concentration also affected the blood concentrations of calcium and subsequently magnesium. Rumen fill had an effect on BC score and liver enzyme activity. Glutathione peroxidase, which is used to assess the levels of selenium in cattle, had no significant relationship with the other variables and was therefore isolated in the model. CONCLUSION: The use of a multidimensional model, which in this study was an additive Bayesian network, showed the relationships between the biochemical variables in the metabolic profiles and the scoring systems commonly used for the management of dairy cow herds. The relationships between the biochemical variables and the four scoring systems can be used to manage dairy herds more effectively. CLINICAL RELEVANCE: The biochemical variables used in metabolic profiles were correlated with health scoring systems commonly used in dairy herds. The latter can be carried out more rapidly and at a lower cost than metabolic profiles. In dairy cows with metabolic diseases or fertility disorders, scoring systems do not replace detailed evaluations that include metabolic profiles.

[Screening of febrile cows using a small handheld infrared thermography device]. / Anwendung einer kleinen tragbaren Wärmebildkamera zum Screening auf Kühe mit Fieber.

OBJECTIVE: As dairy herds increase in size, close monitoring of health becomes a necessity, but this is expensive and labour-intensive. Early detection of febrile diseases is essential for economical and welfare reasons and to prevent the spread of disease. The goal of this study was therefore to evaluate a mobile, non-invasive technique for measuring the body temperature of cows that precludes the need for restraint of the animals. MATERIALS AND METHODS: An infrared thermographic imaging camera installed on a smart phone was used to measure the surface temperature of cows. In experiment 1, a metal block heated to defined temperatures was used to obtain infrared thermographic measurements (THM). The accuracy of THM made at different distances from the block and at 2 different ambient temperatures was determined. In experiment 2, non-febrile cows underwent infrared thermographic imaging, and the body regions with the highest correlations between thermographic and rectal temperature were identified. In experiment 3, THM were made in febrile and neighbouring non-febrile cows. RESULTS: In experiment 1, the thermographic and true temperatures of the block had the strongest relationships at 0.5 and 1.0 m (r = 0.98). The ambient temperature had a significant effect on the THM, which had larger variations and greater deviations from the block temperature at 14.8 °C than at 23.8 °C. In experiment 2, the maximum temperature at the eye (r = 0.37), THM at the muzzle (r = 0.28) and the medial canthus (r = 0.27) showed the strongest relationships with the rectal temperature. After correcting the THM with the mean difference between thermographic and rectal temperatures of the non-febrile cows, sensitivities of 88, 90 and 82 %, respectively, were calculated for THM at the muzzle, eye and medial canthus in febrile cows in experiment 3. The corresponding specificities were 6, 23 and 32 %. CONCLUSION AND CLINICAL RELEVANCE: Based on the low specificities of the infrared THM, the thermographic imaging camera has limited usefulness for the mass screening of dairy cows for febrile conditions. Cattle falsely identified as febrile need to be separated, caught and re-examined, which causes unnecessary stress to the animal and increases labour input.

[Changes in claw and leg health and hair cortisol concentration in dairy cows during the transition from tie-stall to free-stall housing - A study of a medium-sized farm]. / Veränderungen der Klauen- und Gliedmaßengesundheit sowie Haarkortisolkonzentration von Milchkühen bei der Umstellung von Anbinde- auf Laufstallhaltung.

OBJECTIVE: Claw health and carpal and tarsal lesions were assessed in a dairy herd during the transition from a tie-stall to a free-stall barn. The stress associated with the change in housing was also evaluated. MATERIALS AND METHODS: The initial size of the herd was 57 dairy cows, which were evaluated 4 times, 4-5 months apart, in a hoof-trimming chute. Claw horn and skin lesions of the foot were considered separately. The carpi and hocks were assessed for hair loss and skin lesions, and the hocks were also evaluated for swelling. Tail hair samples were collected from all cows during the second visit, and the cortisol concentration of 3 different sections of the hair was measured. RESULTS: The high prevalence of digital dermatitis and other skin lesions in the hind legs seen in the tie-stall barn (49 %) did not change significantly during the 14-month study period and was 46 % at the last visit. Heel horn erosions of the hind feet were rare in the tie-stall barn (14 %), but had a prevalence of 100 % at the end of the study. There was a trend for a decrease in the prevalence of other claw horn lesions. The prevalence and severity of carpal and hock lesions decreased significantly in the free-stall barn. Compared to values in cows at the tie-stall barn, the hair cortisol concentration was significantly higher during the transition period and at the free-stall barn. DISCUSSION AND CONCLUSIONS: The target variables were subjected to a multitude of factors but it can be assumed that the more comfortable lying surface in the free-stall barn had the most significant effect on carpal and tarsal joint health. The fluctuating prevalence of claw horn lesions indicates that claws health should be monitored closely. The increase in hair cortisol concentration after the transition to the free-stall barn could imply increased stress, but washout of cortisol in more distal hair segments could not be ruled out. CLINICAL RELEVANCE: The results of the present report cannot be directly applied to other herds; however, the significance of cow comfort is highlighted by the presence of fewer carpal and hock lesions. The significant increase in the prevalence of heel horn erosions indicates that the horn capsule is compromised under free-stall conditions.

Sonographic characteristics of the placenta, uterine wall, and placentomes during pregnancy in cows.

OBJECTIVE: In human medicine, contrary to bovine medicine, close monitoring of risk pregnancies is an integral part of obstetrics. A prerequisite for this is the knowledge of the normal findings during pregnancy. MATERIAL AND METHODS: For this purpose serial transrectal sonographic examination of the placentomes, uterine wall, and fetal membranes were carried out in 24 healthy (mean age 8.1 ± 3.7 years, Brown Swiss [n = 21], Red Holstein [n = 2], Simmental [n = 1]) cows from week 6 to 43 of gestation. An 8-MHz linear transducer was used to assess the thickness and appearance of the endometrium and myometrium, the height and width of placentomes, the thickness of the uterine wall including the adjacent chorion laeve (combined thickness of uterus and placenta, CTUP), and the echogenicity of the fetal fluids. The uterine wall and the placentomes were measured in 4 different zones of both uterine sides including a zone near the cervix, at the corpus near to the bifurcation, at the middle, and near the tip of the uterine horn. RESULTS: Placentome height and width were closely correlated with gestational age (height: r = 0.78; width: r = 0.83; both p < 0.0001). Placentome size increased progressively in all uterine zones until week 27, after which time their growth slowed until week 31 and then plateaued until parturition. Placentomes in the fetus-bearing horn were larger than in the non-fetus-bearing horn (p < 0.01) and were significantly smaller (height and width) near the tip of the horn than in the other 3 zones (p < 0.001 to < 0.01). The mean thickness of endometrium and myometrium, myometrium at the base of the placentome, and the mean CTUP did not change significantly during gestation. The echogenicity of the allantoic fluid did not change, but the amniotic fluid became more echogenic during gestation (p < 0.0001). CONCLUSION AND CLINICAL RELEVANCE: Sonographic examination of placentomes and amniotic fluid are a promising diagnostic tool for the estimation of the duration of bovine pregnancies and for diagnosing possible complications.

Clinical and laboratory findings, treatment and outcome in 145 cows with type-2 abomasal ulcer.

This study involved 145 cows with type-2 abomasal ulcer. The most common clinical signs were, in decreasing order of frequency, depressed demeanour (100%), partial or complete anorexia (93%), rumen atony (91%), tachycardia (90%), dark or black manure (80%), prolonged capillary refill time (71%), pale mucous membranes (69%) and tachypnoea (62%). The most common abnormal laboratory findings were azotaemia (89%), low haematocrit (82%), hypokalaemia (81%), hypoproteinaemia (74%) and metabolic acidosis (61%). Ten cows were euthanased immediately after, or died during, the initial examination, and treatment was started (day 0) in 135 cows. Treatment included blood transfusion, sodium chloride/glucose solution, calcium borogluconate, vitamin C and metamizole. Fourteen cows also underwent right-flank laparotomy because of displaced abomasum (n = 7) or to rule out other causes of gastrointestinal haemorrhage (n = 7). The mean heart rate decreased significantly from 108 bpm on day 0 to 88 bpm on day 3. The haematocrit decreased significantly in cows that did not receive blood and increased significantly in the transfused cows during this period. The plasma protein concentration also increased significantly in transfused cows. Ninety-one (67%) of the 135 treated cows recovered and were discharged after a mean hospitalisation period of nine days, and 44 cows (33%) failed to respond to treatment and were euthanased or died. Aggressive treatment, which should include blood transfusion when indicated, is warranted in valuable cows because >50% can be expected to return to full production in the long term.

Production of neutralizing antibodies against the secreted Clostridium chauvoei toxin A (CctA) upon blackleg vaccination.

Clostridium chauvoei is the etiologic agent of blackleg in cattle, inducing fever, severe myonecrosis, oedemic lesions and ultimately death of infected animals. The pathogen often results in such rapid death that antibiotic therapy is futile and thus vaccination is the only efficient strategy in order to control the disease. The ß-barrel pore forming leucocidin Clostridium chauvoei toxin A (CctA) is one of the best characterised toxins of C. chauvoei and has been shown to be an important virulence factor. It has been reported to induce protective immunity and is conserved across C. chauvoei strains collected from diverse geographical locations for more than 50 years. The aim of this study was to identify the location of the CctA toxin during liquid culture fermentation and to use CctA to develop an in vitro assay to replace the current guinea pig challenge assay for vaccine potency in standard batch release procedures. We report that CctA is fully secreted in C. chauvoei culture and show that it is found abundantly in the supernatant of liquid cultures. Sera from cattle vaccinated with a commercial blackleg vaccine revealed strong haemolysin-neutralizing activity against recombinant CctA which reached titres of 1000 times 28 days post-vaccination. Similarly, guinea pig sera from an official potency control test reached titres of 600 times 14 days post-vaccination. In contrast, ELISA was not able to specifically measure anti-CctA antibodies in cattle serum due to strong cross-reactions with antibodies against other proteins present pre-vaccination. We conclude that haemolysin-neutralizing antibodies are a valuable measurement for protective immunity against blackleg and have the potential to be a suitable replacement of the guinea pig challenge potency test, which would forego the unnecessary challenge of laboratory animals.

Bovine Fetal Placenta During Pregnancy and the Postpartum Period.

Bovine abortion is a worldwide problem, but despite extensive histopathologic and molecular investigations, the cause of abortion remains unclear in about 70% of cases. Cellular debris is a commonly observed histopathologic finding in the fetal placenta and is often interpreted as necrosis. In this study, the nature of this cellular debris was characterized, and histologic changes in the normal fetal placenta during pregnancy and after delivery were assessed. In addition, the presence of the most common abortifacient pathogens in Switzerland ( Chlamydiaceae, Coxiella burnetii, Neospora caninum) was tested by polymerase chain reaction. We collected 51 placentomes and 235 cotyledons from 41 and from 50 cows, respectively. In total, cellular debris was present in 48 of 51 (94%) placentomes and in 225 of 235 (96%) cotyledons, inflammation occurred in 1 of 51 (2%) placentomes and in 46 of 235 (20%) cotyledons, vasculitis was seen in 1 of 51 (2%) placentomes and 46 of 235 (20%) cotyledons, and 18 of 51 (35%) placentomes and 181 of 235 (77%) cotyledons had mineralization. The amount of cellular debris correlated with areas of positive signals for cleaved caspase 3 and lamin A. Therefore, this finding was interpreted as an apoptotic process. In total, 10 of 50 cotyledons (20%) were positive for C. burnetii DNA, most likely representing subclinical infections. The results of our study indicate that histologic features in the fetal placenta such as cellular debris, inflammation, vasculitis, and mineralization must be considered physiological processes during pregnancy and after delivery. Therefore, their presence in placentae of aborted fetuses must be interpreted with caution and might not be necessarily linked to an infectious cause of abortion.

RNA-Seq analysis during the life cycle of Cryptosporidium parvum reveals significant differential gene expression between proliferating stages in the intestine and infectious sporozoites.

Cryptosporidium parvum is a major cause of diarrhoea in humans and animals. There are no vaccines and few drugs available to control C. parvum. In this study, we used RNA-Seq to compare gene expression in sporozoites and intracellular stages of C. parvum to identify genes likely to be important for successful completion of the parasite's life cycle and, thereby, possible targets for drugs or vaccines. We identified 3774 protein-encoding transcripts in C. parvum. Applying a stringent cut-off of eight fold for determination of differential expression, we identified 173 genes (26 coding for predicted secreted proteins) upregulated in sporozoites. On the other hand, expression of 1259 genes was upregulated in intestinal stages (merozoites/gamonts) with a gene ontology enrichment for 63 biological processes and upregulation of 117 genes in 23 metabolic pathways. There was no clear stage specificity of expression of AP2-domain containing transcription factors, although sporozoites had a relatively small repertoire of these important regulators. Our RNA-Seq analysis revealed a new calcium-dependent protein kinase, bringing the total number of known calcium-dependent protein kinases (CDPKs) in C. parvum to 11. One of these, CDPK1, was expressed in all stages, strengthening the notion that it is a valid drug target. By comparing parasites grown in vivo (which produce bona fide thick-walled oocysts) and in vitro (which are arrested in sexual development prior to oocyst generation) we were able to confirm that genes encoding oocyst wall proteins are expressed in gametocytes and that the proteins are stockpiled rather than generated de novo in zygotes. RNA-Seq analysis of C. parvum revealed genes expressed in a stage-specific manner and others whose expression is required at all stages of development. The functional significance of these can now be addressed through recent advances in transgenics for C. parvum, and may lead to the identification of viable drug and vaccine targets.

Effect of antimicrobials administered via liquid feed on the occurrence of sulphonamide and trimethoprim resistant Enterobacteriaceae: case-control study.

BACKGROUND: Drugs for the treatment of groups of pigs receiving liquid feed are frequently mixed into the feed and administered via the pipelines of the feeding installations. In-feed antimicrobials may select antimicrobial resistant strains among the bacteria which form the biofilm of these pipelines and are shed into the liquid feed. OBJECTIVE AND METHODS: In order to evaluate the risk of selecting antimicrobial resistant bacteria in the biofilm of liquid feeding installations, the effect of the administration of antimicrobials via the pipelines on the occurrence of antimicrobial resistance in the feed was examined in a case-control study. A premix containing either sulphonamide plus trimethoprim or sulphonamide plus chlortetracycline plus tylosin or chlortetracycline was administered via the pipelines to each batch of bought-in fattening pigs in 7, 3 and 3 case farms respectively, whereas antimicrobials had not been administered via the liquid feeding installation for at least 2 years in the 14 control farms. Enterobacteriaceae and sulphonamide-trimethoprim resistant Enterobacteriaceae were counted in twelve and eight feed samples collected in each case and in each control farm respectively during one fattening period. The semiparametric Generalized Estimating Equations (GEE) method was used for the statistical data analysis. RESULTS: The ratio of sulphonamide and trimethoprim resistant to total Enterobacteriaceae was higher in the feed of the case farms compared to the control farms (P < 0.001) and did not decrease after treatment during the fattening period. CONCLUSION: The administration of antimicrobials via the liquid feeding installation selects antibiotic resistant bacteria in the biofilm lining the pipelines, which may contaminate the liquid feed for extended periods and transmit their resistance genes to the gastrointestinal flora of the pigs. Alternatives to the administration of antimicrobials via pipelines of liquid feeding installations for group treatment should be developed.

Cortisol concentration of regrown hair and hair from a previously unshorn area in dairy cows.

This study determined cortisol concentrations in hair that had grown for one month and in hair from a previously unshorn area and examined the effects of calendar month, pregnancy and illness on hair cortisol concentrations in dairy cows. The study was conducted over a one-year period using 27 cows. Electric clippers were used to collect two hair samples per cow each month. The first sample (A sample) consisted of hair that had grown for one month in a pre-clipped area and the second sample (B sample) comprised all hair from a previously unshorn area. Liquid chromatography tandem mass-spectrometry was used for cortisol measurement. The overall mean concentrations for A and B samples did not differ. Cortisol concentrations of A samples were significantly higher in the winter (0.86±0.37pg/mg) than in the fall (0.67±0.33pg/mg). The hair cortisol concentration in A samples increased during pregnancy and the maximum concentration of 1.40±1.08pg/mg hair in the month of calving was significantly higher than the concentration measured in the first month (0.66±0.32pg/mg). The findings show that the effect of short-term stressors such as parturition on hair cortisol concentrations are more easily detected in hair that has grown for one month than in hair from a previously unshorn area.

Asymmetrical lumbosacral transitional vertebrae in dogs may promote asymmetrical hip joint development.

OBJECTIVES: This study examines the relationship between the morphology of the lumbosacral transitional vertebra (LTV) and asymmetrical development of the hip joints in dogs. METHODS: A total of 4000 dogs which had been consecutively scored for canine hip dysplasia were checked for the presence of a LTV. A LTV was noted in 138 dogs and classified depending on the morphology of the transverse processes and the degree of contact with the ilium. RESULTS: In dogs with an asymmetrical LTV, the hip joint was significantly more predisposed to subluxation and malformation on the side of the intermediate or sacral-like transverse process (p <0.01), on the side of the elevated pelvis (p <0.01), or when an asymmetrical LTV resulted in pelvic rotation on its long axis (p <0.01), whereas hip joint conformation was less affected on the side featuring a free transverse process (p <0.01). CLINICAL SIGNIFICANCE: The results support our hypothesis that an asymmetrical LTV favours pelvic rotation over its long axis, resulting in inadequate femoral head coverage by the acetabulum on one side. Inadequate coverage of the femoral head favours subluxation, malformation of the hip joint, and secondary osteoarthritis. Asymmetrical hip conformation may therefore be the sequela of a LTV and mask or aggravate genetically induced canine hip dysplasia.

Selective Pressure Promotes Tetracycline Resistance of Chlamydia Suis in Fattening Pigs.

In pigs, Chlamydia suis has been associated with respiratory disease, diarrhea and conjunctivitis, but there is a high rate of inapparent C. suis infection found in the gastrointestinal tract of pigs. Tetracycline resistance in C. suis has been described in the USA, Italy, Switzerland, Belgium, Cyprus and Israel. Tetracyclines are commonly used in pig production due to their broad-spectrum activity and relatively low cost. The aim of this study was to isolate clinical C. suis samples in cell culture and to evaluate their antibiotic susceptibility in vitro under consideration of antibiotic treatment on herd level. Swab samples (n = 158) identified as C. suis originating from 24 farms were further processed for isolation, which was successful in 71% of attempts with a significantly higher success rate from fecal swabs compared to conjunctival swabs. The farms were divided into three treatment groups: A) farms without antibiotic treatment, B) farms with prophylactic oral antibiotic treatment of the whole herd consisting of trimethoprime, sulfadimidin and sulfathiazole (TSS), or C) farms giving herd treatment with chlortetracycline with or without tylosin and sulfadimidin (CTS). 59 isolates and their corresponding clinical samples were selected and tested for the presence or absence of the tetracycline resistance class C gene [tet(C)] by conventional PCR and isolates were further investigated for their antibiotic susceptibility in vitro. The phenotype of the investigated isolates was either classified as tetracycline sensitive (Minimum inhibitory concentration [MIC] < 2 µg/ml), intermediate (2 µg/ml ≤ MIC < 4 µg/ml) or resistant (MIC ≥ 4 µg/ml). Results of groups and individual pigs were correlated with antibiotic treatment and time of sampling (beginning/end of the fattening period). We found clear evidence for selective pressure as absence of antibiotics led to isolation of only tetracycline sensitive or intermediate strains whereas tetracycline treatment resulted in a greater number of tetracycline resistant isolates.

Prevalence of Chlamydial Infections in Fattening Pigs and Their Influencing Factors.

Chlamydial infections in pigs are associated with respiratory disease, diarrhea, conjunctivitis and other pathologies. The aim of this study was to define the prevalence of Chlamydiaceae in Swiss fattening pigs by applying sensitive and specific detection methods and to correlate prior antibiotic treatment and farm related factors with differences in prevalence. Conjunctival and fecal swabs were collected from 636 pigs in 29 Swiss fattening pig farms with and without antibiotic treatment, at the beginning and the end of the fattening period. The swabs were screened by real-time PCR for Chlamydiaceae. For the chlamydial detection and species-identification, a DNA-microarray analysis was performed. All farms were positive for Chlamydiaceae with 94.3 and 92.0% prevalence in fecal swabs as well as 45.9 and 32.6% in conjunctival swabs at the first and second time points, respectively. Antibiotic treatment could not clear the infection on herd level. Potential contact with wild boars was a significant risk factor, while hygiene criteria did not influence chlamydial prevalence. A correlation of chlamydial positivity to diarrhea, but not to conjunctivitis was evident. Chlamydia suis was the predominant species. Mixed infections with C. suis and C. pecorum were common, with a substantial increase in C. pecorum positivity at the end of the fattening period, and this finding was associated with ruminant contact. C. abortus was detected in one conjunctival swab. In this study, C. suis inhabited the intestinal tract of nearly all examined pigs, implying a long-term infection. C. pecorum was also common and might be transmitted to pigs by ruminants.

Evaluation of eating and rumination behaviour in 300 cows of three different breeds using a noseband pressure sensor.

BACKGROUND: Eating and rumination variables were recorded in 300 healthy lactating dairy cows of 3 different breeds (100 Brown Swiss, 100 Holstein-Friesian, 100 Swiss Fleckvieh cows). Eating and rumination variables were monitored during a 24-h period using an automated system that recorded jaw movements via a pressure sensor integrated into the noseband of a halter. Phases of eating and rumination were reliably identified in the recordings based on typical patterns seen in previous studies. The variables analysed included duration of eating and rumination, number of chewing cycles during eating and rumination, number of regurgitated cuds and number of chewing cycles per cud. RESULTS: The cows ate for an average of 265 ± 54 min and chewed 17,077 ± 3646 times per day. The duration of rumination was 441 ± 71 min, there were 578 ± 94 cuds per day and 55 ± 10 chewing cycles per cud. There were significant correlations (P < 0.01) between duration of eating and number of chewing cycles during eating (r = 0.94), between duration of rumination and number of chewing cycles per regurgitated cud (r = 0.56) and between duration of rumination and number of regurgitated cuds per day (r = 0.53). CONCLUSIONS: The eating and rumination variables established in the present study reflect the current conditions of Swiss dairy farming and serve as reference intervals for assessing sick cows.

Transmission of border disease virus from a persistently infected calf to seronegative heifers in early pregnancy.

BACKGROUND: This study describes the transmission of border disease virus (BDV) from a persistently infected calf to seronegative heifers in early pregnancy, resulting in persistently infected fetuses. On day 50 of pregnancy (= day 0 of the infection phase), six heifers were co-housed in a free stall with a bull calf persistently infected with BDV (pi BVD) for 60 days. The heifers underwent daily clinical examination, and blood samples were collected regularly for detection of pestiviral RNA and anti-pestivirus antibodies. After day 60 (= day 110 of pregnancy), the heifers were slaughtered, and the fetuses and placentae underwent post-mortem and immunohistochemical examination and RT-PCR for viral RNA detection. RESULTS: Three heifers had mild viraemia from day 8 to day 14, and by day 40 all heifers had pestivirus antibodies identified as anti-BDV antibodies in the serum neutralisation test. The placenta of the three viraemic heifers had histological evidence of inflammation, and fetal organs from these heifers were positive for pestivirus antigen by immunohistochemical examination and for BD viral RNA by RT-PCR and sequencing. Thus, co-housing of heifers in early pregnancy with a pi-BDV calf led to seroconversion in all heifers and persistent fetal infection in three. CONCLUSIONS: Considering that pi-BDV cattle can infect other cattle and lead to persistent infection of the fetus in pregnant cows, BDV should not be ignored in the context of the mandatory BVDV eradication and monitoring program. This strongly suggests that BDV should be taken into account in BVD eradication and control programs.

A study of measurement of noninvasive blood pressure with the oscillometric device, Sentinel, in isoflurane-anaesthetized horses.

OBJECTIVE: To assess accuracy of noninvasive blood pressure (NIBP) measured by oscillometric device Sentinel compared to invasive blood pressure (IBP) in anaesthetized horses undergoing surgery. To assess if differences between the NIBP measured by the Sentinel and IBP are associated with recumbency, cuff placement, weight of the horse or acepromazine premedication and to describe usefulness of the Sentinel. STUDY DESIGN: Prospective study examining replicates of simultaneous NIBP and IBP measurements. ANIMALS: Twenty-nine horses. METHODS: Invasive blood pressure was measured via a catheter in the facial artery, transverse facial artery or metatarsal artery. NIBP was measured using appropriate size cuffs placed on one of two metacarpal or metatarsal bones or the tail in random order. With both techniques systolic (SAP), mean (MAP), and diastolic (DAP) arterial blood pressures and heart rates (HR) were recorded. A mixed effects model compared the IBP to the NIBP values and assessed potential effects of catheter placement, localisation of the cuffs in combination with recumbency, weight of the horse or acepromazine premedication. RESULTS: Noninvasive blood pressure yielded higher measurements than IBP. Agreement varied with recumbency and cuff position. Estimated mean differences between the two methods decreased from SAP (lateral recumbency: range -5.3 to -56.0 mmHg; dorsal recumbency: range 0.8 to -20.7 mmHg), to MAP (lateral recumbency: range -1.8 to -19.0 mmHg; dorsal recumbency: range 13.9 to -16.4 mmHg) to DAP (lateral recumbency: range 0.5 to -6.6 mmHg; dorsal recumbency: range 21.0 to -15.5 mmHg). NIBP measurement was approximately two times more variable than IBP measurement. No significant difference between IBP and NIBP due to horse's weight or acepromazine premedication was found. In 227 of 1047 (21.7%) measurements the Sentinel did not deliver a result. CONCLUSION AND CLINICAL RELEVANCE: According to the high variability of NIBP compared to IBP, NIBP measurements as measured by the Sentinel in the manner described here are not considered as an appropriate alternative to IBP to measure blood pressure in anaesthetized horses.

Evaluation of eating and rumination behaviour using a noseband pressure sensor in cows during the peripartum period.

BACKGROUND: Eating and rumination variables were recorded in ten healthy cows over 5 days (group A) to generate reference intervals for comparison with the same variables recorded in ten cows in advanced pregnancy from ten days prepartum to ten days postpartum (group B). A pressure sensor integrated into the noseband of a halter recorded individual chewing movements. The endpoints calculated on a daily basis for each cow included duration of eating and rumination, number of eating and rumination phases, number of chewing cycles during eating and rumination, number of regurgitated cuds and number of chewing cycles per cud. RESULTS: The following reference intervals were established in the cows of group A: duration of eating, 212 to 394 min; number of chewing cycles during eating 13'101 to 26'515; number of eating phases 10 to 24; duration of rumination 304 to 471 min; number of regurgitated cuds 366 to 611; number of chewing cycles per cud 53 to 57; and number of rumination phases 9 to 18. In the cows of group B, duration of eating was 186 min and below the normal range ten days prepartum and decreased to 114 min on the day of calving, after which time it increased significantly to 266 min by day 10. The number of chewing cycles during eating had the same profile as duration of eating. Duration of rumination was in the normal range except for the day of parturition. It varied from 329 to 391 min prepartum, decreased significantly to 214 min on the day of parturition and then more than doubled by day 10. The number of regurgitated cuds had a profile similar to the duration of rumination. The number of chewing cycles per cud was lowest on the day before and the day of parturition and ranged from 45 to 61. CONCLUSIONS: This study showed that eating and rumination variables decrease from ten days before parturition to a minimum on the day of parturition, after which time they increase.

Influence of non ionizing radiation of base stations on the activity of redox proteins in bovines.

BACKGROUND: The influence of electromagnetic fields on the health of humans and animals is still an intensively discussed and scientifically investigated issue (Prakt Tierarzt 11:15-20, 2003; Umwelt Medizin Gesellschaft 17:326-332, 2004; J Toxicol Environment Health, Part B 12:572-597, 2009). We are surrounded by numerous electromagnetic fields of variable strength, coming from electronic equipment and its power cords, from high-voltage power lines and from antennas for radio, television and mobile communication. Particularly the latter cause's controversy, as everyone likes to have good mobile reception at anytime and anywhere, whereas nobody wants to have such a basestation antenna in their proximity. RESULTS: In this experiment, the NIR has resulted in changes in the enzyme activities. Certain enzymes were disabled, others enabled by NIR. Furthermore, individual behavior patterns were observed. While certain cows reacted to NIR, others did not react at all, or even inversely. CONCLUSION: The present results coincide with the information from the literature, according to which NIR leads to changes in redox proteins, and that there are individuals who are sensitive to radiation and others that are not. However, the latter could not be distinctly attributed - there are cows that react clearly with one enzyme while they do not react with another enzyme at all, or even the inverse. The study approach of testing ten cows each ten times during three phases has proven to be appropriate. Future studies should however set the post-exposure phase later on.