Associations between Animal Welfare Indicators and Animal-Related Factors of Slaughter Cattle in Austria.

Three cattle welfare indicators (lameness, dirtiness, and abomasal disorders) were evaluated in 412 slaughter cattle in a cross-sectional study in Austria. The aims of this study were (1) to evaluate the prevalence of lameness, dirtiness of slaughter cattle, and abomasal disorders; and (2) to determine the association between these welfare indicators and animal-related factors (e.g., housing type, carcass weight, transportation and waiting duration of the animals). The lameness prevalence was 0.73%, the abomasal disorders prevalence was 52.43%, and 88.59% of all cattle were contaminated. The latter result indicates that the cattle were kept in a dirty environment. The occurrence of abomasal disorders was associated with cattle housing systems (p ≤ 0.00) and slaughter weight (p = 0.03). The odds for abomasal disorders were 28.0 times higher for cattle housed on slatted flooring compared to cattle kept in a tethered system. The chance for occurrence of abomasal disorders was 3.6 times higher for cattle with a low carcass weight compared to cattle with a high carcass weight. Furthermore, significant associations were found between dirtiness (also referred to as cleanliness or contamination) and husbandry system, sex, and breed. Cattle housed in deep litter boxes had 40.8 times higher odds of being contaminated compared to cattle in a tethered housing system. Cows (odds: 32.9) and heifers (odds: 4.4) had higher odds of being contaminated with feces compared to bulls, whereby female calves (odds: 0.09) and male calves (odds: 0.02) had significantly lower odds of being contaminated. Furthermore, the breeds Brown Swiss (odds: 0.26) and Holstein-Friesian (odds: 0.14) had a significantly lower chance of being contaminated compared to Simmental cattle. Other collected factors, such as production system, transportation duration, life days of the cattle, average daily weight gain, carcass classification, and fat coverage, showed no association with the collected welfare indicators. The study presented here indicates that welfare indicators evaluated for slaughter cattle are suitable to assess cattle welfare, and improvements in husbandry may positively impact both the abomasal physiology and cleanliness of cattle.

A systematic review of financial and economic assessments of bovine viral diarrhea virus (BVDV) prevention and mitigation activities worldwide.

Infection with bovine viral diarrhea virus (BVDV) results in major economic losses either directly through decreased productive performance in cattle herds or indirectly, such as through expenses for control programs. The aim of this systematic review was to review financial and/or economic assessment studies of prevention and/or mitigation activities of BVDV at national, regional and farm level worldwide. Once all predefined criteria had been met, 35 articles were included for this systematic review. Studies were analyzed with particular focus on the type of financially and/or economically-assessed prevention and/or mitigation activities. Due to the wide range of possible prevention and/or mitigation activities, these activities were grouped into five categories: i) control and/or eradication programs, ii) monitoring or surveillance, iii) prevention, iv) vaccination and v) individual culling, control and testing strategies. Additionally, the studies were analyzed according to economically-related variables such as efficiency, costs or benefits of prevention and/or mitigation activities, the applied financial and/or economic and statistical methods, the payers of prevention and/or mitigation activities, the assessed production systems, and the countries for which such evaluations are available. Financial and/or economic assessments performed in Europe were dominated by those from the United Kingdom, which assessed mostly vaccination strategies, and Norway which primarily carried out assessments in the area of control and eradication programs; whereas among non-European countries the United States carried out the majority of financial and/or economic assessments in the area of individual culling, control and testing. More than half of all studies provided an efficiency calculation of prevention and/or mitigation activities and demonstrated whether the inherent costs of implemented activities were or were not justified. The dairy sector was three times more likely to be assessed by the countries than beef production systems. In addition, the dairy sector was approximately eight times more likely to be assessed economically with respect to prevention and/or mitigation activities than calf and youngstock production systems. Furthermore, the private sector was identified as the primary payer of prevention and/or mitigation activities. This systematic review demonstrated a lack of studies relating to efficiency calculations, in particular at national and regional level, and the specific production systems. Thus, we confirmed the need for more well-designed studies in animal health economics in order to demonstrate that the implementation and inherent costs of BVDV prevention and/or mitigation activities are justified.

Invited review: Abomasal emptying in calves and its potential influence on gastrointestinal disease.

Creating the ideal nutrition program for calves is a demanding task that has undergone tremendous change in recent years. Products and technologies including novel milk replacers and automated calf feeding systems have been developed to facilitate the ability of dairy producers to feed for higher growth rates before weaning. The creation of new feeding programs and milk replacers has to be looked at carefully, not only from a nutrition point of view but also from the perspective of a potential effect on physiologic digestion and calf health. Abomasal emptying is a critical factor that may link nutrition and disease. The purpose of this article is to review both intrinsic and extrinsic factors that are responsible for abomasal emptying. Predominant extrinsic factors controlling abomasal emptying include meal volume, energy density, and osmolality along with the content and source of protein. This article also reviews experimental methods used to measure abomasal emptying in the calf including those that would be appropriate for use under field conditions. Among these methods, the use of ultrasonography and different absorption tests (d-xylose, acetaminophen) as tools to measure abomasal emptying are discussed. The relationship between abomasal emptying and disease is explored, particularly as it relates to abomasal bloat. Abomasal bloat is a complex syndrome that seems to be increasing in frequency and whose etiology likely at least partially involves slowing of abomasal emptying. Suggestions for minimizing the effect of feeding programs on abomasal emptying are explored as well as needs for future research.

The effect of bovine viral diarrhoea virus on fertility in dairy cows: two case-control studies in the province of Styria, Austria.

Bovine viral diarrhoea (BVD) leads to substantial economic losses in beef and dairy herds worldwide. Two case-control studies were carried out using production data from 1996 to 2012 to analyse the impact of BVD virus (BVDV) on fertility in dairy herds in the province of Styria during an eradication programme. In study 1, herds in which at least one persistently BVDV-infected (PI) animal was detected (case herds) were compared to a group of control herds proven free from BVDV infection (contro herds). In study 2, within BVD infected herds the period during which P animals were present (exposed period) was compared to the period after successful BVD eradication (unexposed period). Calving interval (CAl) and the probability of a first service conception (FSC) were used as indicators in a mixed regression model to investigate the impact of BVD on reproductive performance. The model results indicated that BVD had a significant influence on CAl and FSC. Cows from control herds were 1.1 times more likely to conceive at first service compared to cows from case herds and cows served during the BVDV unexposed period were 1.3 times more likely to conceive at first service than those inseminated during the exposed period. In BVD-infected herds the CAI averaged seven days shorter in unexposed periods than in exposed periods. Besides BVD the animal breed and the parity substantially impact the analysed fertility indicators.

Clinical and biochemical signs in Fleckvieh cattle with genetically confirmed Fanconi-Bickel syndrome (cattle homozygous for Fleckvieh haplotype 2).

Fanconi-Bickel Syndrome (FBS) is an autosomal recessive disorder of the carbohydrate metabolism, which has been reported in human and some animals (OMIA 000366-9913). In Fleckvieh cattle it is caused by mutations in SLC2A2, a gene encoding for glucose transporter protein 2 (GLUT2), which is primarily expressed in liver, kidney, pancreas and intestines. The causal mutation resides in a previously reported Fleckvieh Haplotype 2 (FH-2). FH-2 homozygous individuals are rare, but due to widespread use of heterozygous bulls in artificial insemination, heterozygous animals are likely to be present in a larger number in the cattle population. Two clinical cases of Fleckvieh cattle with a syndrome resembling the phenotypic appearance of FBS are presented in the present study describing the association between the clinical manifestations of FBS and the postulated frameshift mutation in bovine SLC2A2. Clinical examination showed poor growth, retarded development, polyuria, and polydipsia. Laboratory analyses showed an increased plasma glucose but normal insulin concentration and increased renal glucose excretion. Histopathological examination of kidney and liver samples revealed massively increased liver glycogen storage and nephrosis. Sires of both cases were tested positive for being heterozygous carriers for the same frameshift mutation in SLC2A2 as was originally reported in Fleckvieh cattle. DNA of both cases described was analyzed and Sanger sequencing confirmed homozygosity for the frameshift mutation in SLC2A2.

Complete ostectomy of middle phalanx and partial ostectomy of proximal phalanx in a Brown Swiss calf for treatment of purulent arthritis of the proximal interphalangeal joint and adjacent severe osteomyelitis.

A five month old Brown Swiss heifer calf (212 kg body mass) with severe left hind limb lameness, caused by a wound of the lateral digit was referred to the veterinary teaching hospital. The calf showed a score 4 of 5 lameness on the left hind limb. A scarified skin lesion with a fistula formation and purulent exudate was observed at the level of the proximal interphalangeal joint (PIJ) of the lateral digit of the left hind. The PIJ region and the lateral digit were severely swollen and painful. Ultrasonography showed a moderate anechoic effusion of the lateral digital flexor tendon sheet (DFTS) and a severe heterogeneous hypoechoic effusion with some small hyperechoic areas of the plantar and dorsal pouch of the PIJ. In addition, a highly irregular contour of the dorsal and abaxial surface of the phalanx media (P2) and the distal aspect of the proximal phalanx (P1) were imaged. Based on physical examination and ultrasonographic findings, the diagnosis was chronic purulent arthritis of the PIJ, osteitis of P2 and the distal end of P1 with suspected adjacent osteomyelitis. Complete ostectomy of P2 and ostectomy of the distal part of the P1 of the lateral digit was performed with an oscillating saw through the extended debrided wound. The lameness improved subsequently and 21 days post-surgery the calf was discharged from the clinic without lameness, and with a wooden block attached to the healthy claw. A year later the heifer was pregnant and still in the herd, during this period it did not exhibit lameness. The described surgical technique resulted in an excellent long-term outcome and may be considered in cases of severe purulent joint infection of the PIJ with osteolytic processes in adjacent bones, as a digit salvage procedure especially for young cattle.

A missense mutation in TUBD1 is associated with high juvenile mortality in Braunvieh and Fleckvieh cattle.

BACKGROUND: Haplotypes with reduced or missing homozygosity may harbor deleterious alleles that compromise juvenile survival. A scan for homozygous haplotype deficiency revealed a short segment on bovine chromosome 19 (Braunvieh haplotype 2, BH2) that was associated with high juvenile mortality in Braunvieh cattle. However, the molecular genetic underpinnings and the pathophysiology of BH2 remain to be elucidated. RESULTS: The frequency of BH2 was 6.5 % in 8,446 Braunvieh animals from the national bovine genome databases. Both perinatal and juvenile mortality of BH2 homozygous calves were higher than the average in Braunvieh cattle resulting in a depletion of BH2 homozygous adult animals (P = 9.3x10(-12)). The analysis of whole-genome sequence data from 54 Braunvieh animals uncovered a missense mutation in TUBD1 (rs383232842, p.H210R) that was compatible with recessive inheritance of BH2. The availability of sequence data of 236 animals from diverse bovine populations revealed that the missense mutation also segregated at a low frequency (1.7 %) in the Fleckvieh breed. A validation study in 37,314 Fleckvieh animals confirmed high juvenile mortality of homozygous calves (P = 2.2x10(-15)). Our findings show that the putative disease allele is located on an ancestral haplotype that segregates in Braunvieh and Fleckvieh cattle. To unravel the pathophysiology of BH2, six homozygous animals were examined at the animal clinic. Clinical and pathological findings revealed that homozygous calves suffered from chronic airway disease possibly resulting from defective cilia in the respiratory tract. CONCLUSIONS: A missense mutation in TUBD1 is associated with high perinatal and juvenile mortality in Braunvieh and Fleckvieh cattle. The mutation is located on a common haplotype likely originating from an ancient ancestor of Braunvieh and Fleckvieh cattle. Our findings demonstrate for the first time that deleterious alleles may segregate across closed cattle breeds without recent admixture. Homozygous calves suffer from chronic airway disease resulting in poor growth performance and high juvenile mortality. The respiratory manifestations resemble key features of diseases resulting from impaired function of airway cilia.

Homozygous haplotype deficiency reveals deleterious mutations compromising reproductive and rearing success in cattle.

BACKGROUND: Cattle breeding populations are susceptible to the propagation of recessive diseases. Individual sires generate tens of thousands of progeny via artificial insemination. The frequency of deleterious alleles carried by such sires may increase considerably within few generations. Deleterious alleles manifest themselves often by missing homozygosity resulting from embryonic/fetal, perinatal or juvenile lethality of homozygotes. RESULTS: A scan for homozygous haplotype deficiency in 25,544 Fleckvieh cattle uncovered four haplotypes affecting reproductive and rearing success. Exploiting whole-genome resequencing data from 263 animals facilitated to pinpoint putatively causal mutations in two of these haplotypes. A mutation causing an evolutionarily unlikely substitution in SUGT1 was perfectly associated with a haplotype compromising insemination success. The mutation was not found in homozygous state in 10,363 animals (P=1.79×10(-5)) and is thus likely to cause lethality of homozygous embryos. A frameshift mutation in SLC2A2 encoding glucose transporter 2 (GLUT2) compromises calf survival. The mutation leads to premature termination of translation and activates cryptic splice sites resulting in multiple exon variants also with premature translation termination. The affected calves exhibit stunted growth, resembling the phenotypic appearance of Fanconi-Bickel syndrome in humans (OMIM 227810), which is also caused by mutations in SLC2A2. CONCLUSIONS: Exploiting comprehensive genotype and sequence data enabled us to reveal two deleterious alleles in SLC2A2 and SUGT1 that compromise pre- and postnatal survival in homozygous state. Our results provide the basis for genome-assisted approaches to avoiding inadvertent carrier matings and to improving reproductive and rearing success in Fleckvieh cattle.