Reproducibility of bovine neonatal pancytopenia (BNP) via the application of colostrum

A haemorrhagic diathesis has been observed in young calves since 2007 which is described as bovine neonatal pancytopenia (BNP) and presents a completely new disease. The objectives of our investigation were to test if BNP could be reproduced using colostrum of cows with a BNP history and pre-colostral calves from farms where BNP has not been observed. In the present experiment, 22 German Holstein calves from BNP-free farms were fed four to six hours after birth 2.5 l colostrum from cows which had been reported to have had at least one calf with BNP in the last lactation. We distinguished three different experimental groups according to the composition of the colostrum. In experimental group I, each of the six calves received colostrum of a single cow, in experimental group II all six calves received colostrum from the same cow and in experimental group III each of the ten calves received a colostrum mix from ten different cows. Clinical signs of BNP were observed in 50% of the calves in experimental group I, 67% of the calves in experimental group II and all calves in experimental group III. The lethality in the three experimental groups was significantly different with rates of 16.7%, 66.7% and 80%, respectively. Calves fed with a colostrum-mix in experimental group III had the highest lethality. Neither the farm nor the amount of the colostrum fed had a significant effect on the occurrence and course of BNP. The profiles for thrombocytes, leucocytes and erythrocytes significantly differed in dependence of the severity of BNP signs. Calves with non-lethal BNP showed thrombocytopenia with values below 100 G/l on the 1th to 3rd and the 7th to 11th day of life. In calves with lethal BNP, thrombocytes decreased under 50 G/l from day 5. In calves with non-lethal BNP, a decrease of the leucocytes under the threshold was present only for a short period of time. In calves with lethal BNP, leucocytes decreased in the first 5 days after birth continuously and increased on the 6th to the 8th day to normal values and then a rapid decrease occurred. Erythrocytes decreased under the normal threshold just in the last two days before the calves died or were euthanized. Thus, the present experiments showed that colostrum of cows with a BNP-history and vaccination with PregSure BVD from Pfizer caused lethal BNP. We can assume that the different reactions of the calves are due to immunogenetic reactions to colostral alloreactive antibodies. The reaction spectrum of calves depends on the presence of antigens which can react with these colostral antibodies. The experimental results can explain the different incidences of BNP within and among farms as well as between breeds.     

High-resolution ultrasonography of xenografted domestic cat ovarian cortex

Transplantation of ovarian tissue has high potential for female gamete conservation. However, optimal timing of oocyte recovery for in vitro maturation and fertilization is still critical. Therefore the aim of the present study was to use high-resolution transcutaneous ultrasonography to monitor follicular development within xenografted ovarian tissue. Ovarian cortex fragments (n=44) from domestic cats were transplanted into athymic nude rats (n=12). Graft development in the animals was assessed weekly by high frequency ultrasound (10-22 MHz) under two different FSH regimes. Blood collection for serum estradiol determination and vaginal smears were performed simultaneously. The xenografts were removed at different time points according to the ultrasound findings. The survival rate of the transplants 4 weeks after surgery was 54.5% and antral follicular growth was observed within 10 grafts from 5 different hosts (8.6 +/- 6.43 follicles per graft). Early follicle antrums could be detected from 0.4 mm onwards. The growth rate of the antral cavity was calculated from weekly measurements (0.56 +/- 0.44 mm per week). Although vaginal cells and estradiol levels followed a cyclic pattern, no correlation was found between follicular diameter, estradiol and keratinized vaginal cells. We recovered 5, 1 and 4 cumulus oocyte complexes from three different individuals during weeks 19, 21, and 23 respectively. Extrusion of a polar body (1 oocyte) and germinal vesicle break down (7 oocytes) indicated progression of maturation after in vitro culture. We conclude that ultrasonography und provided a reliable method to examine xenograft survival and follicular development within the grafts. Furthermore, this technique is suitable for assessment of the efficiency of hormonal treatment and narrowing of the optimal time frame for oocyte retrieval. To our knowledge, this is the first report of the in vivo development of early antral follicles in mammalian species.     

Expert opinion based modelling of the risk of human infection with H5N1 through the consumption of poultry meat in Germany

According to current scientific opinion the risk of human infection with H5N1 via preparation and consumption of poultry meat is negligible.This opinion has not yet been challenged by a formal risk assessment, due to the lack of empirical data. We have developed a scenario pathway model as a conceptual framework for a formal assessment of the H5N1 risk to humans through consumption of poultry meat and parameterise the model using information derived from expert opinions. The aim of this study was to investigate whether the notion of an overall negligible risk via the oral infection route is consistent with ad hoc data and expert opinions on the relevant parameters of the model.The model is mainly based on expert opinion. A stochastic Monte-Carlo simulation was conducted which took into consideration (amongst others) the exposure and infection of chicken (broiler and layer), turkeys, ducks and geese, the probabilities of detection prior to slaughter, virus survival and contamination during slaughter, as well as during the cutting and preparation of meat in commercial plants and in private households, respectively. The empirical consumption pattern for poultry meat in Germany was taken into account in the simulation.The results show that the risk for the individual consumer is practically zero whereas up to 23 cases per year in Germany might occur if the upper (more pessimistic) ranges of the expert opinions apply.The finding of a low but non-negligible risk to the population is discussed in relation to the epidemiological information available from recent outbreaks in South East Asia.     

Evaluation and treatment of a posttraumatic intrahepatic biloma in a dog

A 9 mo old male mixed-breed dog was presented with a history of chronic vomiting and fever after undergoing a cholecystectomy for the management of traumatic cystic duct rupture associated with biliary effusion 10 days before referral. A 6 cm × 6 cm intrahepatic bile collection, a biloma, was diagnosed on abdominal ultrasound and fine-needle aspiration. The biloma was treated with percutaneous catheter drainage under ultrasonographic guidance. Two years after aspiration, the dog continued to do well.     

Schiff-Sherrington syndrome in a 7-year-old zebra mare (Equus quagga)

A 7-year-old plains zebra (Equus quagga) mare was presented to the Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Germany as an emergency. The owner reported that the mare was unable to stand after a suspected traumatic episode at the home yard. The mare was transported in lateral recumbency in a trailer. Clinical examination revealed tachycardia (up to 102 beats/min), tachypnoea (28 breaths/min), mild fever (38.7°C) and clinical dehydration with elastic skin and dry and red mucous membranes. Neurological examination showed paraplegia with complete loss of nociception of the mid-thoracic region and caudal to it. In contrast, examination of the thoracic limbs revealed marked extensor rigidity and hyperaesthesia resulting in an enhanced acute response to minimal touch of the neck and shoulder region. Lateral radiographs of the thoracic vertebral column led to the diagnosis of a complete fracture of the vertebral body of the 7th thoracic (T) vertebra with suspected traumatic compression of the spinal cord. Post-mortem examination confirmed the diagnosis. Gross pathology revealed a complete comminuted fracture of T7 with marked compression of the spinal cord. This is the first report describing the clinical, radiological and pathological findings of a fracture of a thoracic vertebra leading to a Schiff-Sherrington syndrome in a zebra (Equus quagga).     

Effects of different media on proliferation and differentiation capacity of canine, equine and porcine adipose derived stem cells

Adult stem cells are of particular interest for therapeutic use in the field of regenerative medicine. Adipose-derived mesenchymal stem cells (ASCs) are an attractive stem cell source for all fields of regenerative medicine because adipose tissue - and therewith cells - can easily be harvested from each donor. However, common expansion using fetal bovine serum (FBS) can not be used for clinical applications as xenogenic proteins must be avoided. Adipose tissue from equine, canine and porcine donors was digested with collagenase to isolate ASCs. ASCs were either expanded in a cell culture medium supplemented with FBS or in a serum-free medium (UltraCulture; UC) supplemented with a serum substitute (UltroserG). From all three animal species, the adipogenic and osteogenic differentiation potential of ASCs cultured with different media was analyzed in vitro. Cell proliferation analysis showed a population doubling time of 48-68 h for canine cells, 54-65 h for porcine cells and 54-70 h for equine cells, expanded in different media. Except for porcine ASCs, cells cultured in media supplemented with FBS grew faster than cells expanded in UC medium with UltroserG. Yet, all cells maintained their potential to differentiate into adipocytes and osteoblasts. UltraCulture medium containing UltroserG can for all examined species be recommended if FBS needs to be avoided in the expansion of donor-derived (stem) cells.     

Bovine neonatal pancytopenia in German Holstein calves

Profiles of blood cell counts were evaluated for 15 calves from three different farms. These calves showed petechia in the mucous membranes and in the skin and prolonged secondary bleeding after puncture. The clinical course of the disease could be observed in eleven calves. With exception of one case, the blood cell counts indicated a severe anaemia, leukocytopenia and thrombocytopenia. Out of these 15 calves, six calves survived and the other nine calves died or had to be euthanized due to the severity of the disease. Necropsy of these nine calves revealed petechia in the skin, subcutis, muscles, in inner organs and all serous membranes. Pathohistological examination showed a depletion of the bone marrow and lymphatic tissue in eight calves. These findings confirmed the diagnosis of bovine neonatal pancytopenia (BNP) for eight of these nine calves. Bluetongue virus serotype 8 was tested negatively using PCR. Bovine virus diarrhoea virus (BVDV) was negatively tested using immunofluorescence and cell culture and salmonella species were negatively tested in seven dissected calves. A cluster of toxins was negatively tested in one of the dissected calves. All 15 calves had high antibody titres for BVDV. The BVDV-antibody titres from twelve dams with affected calves were positive in six cases and not detectable in the other six cases. In three of the six dams with not detectable BVDV-antibody titres, calves were fed with colostrum of a further dam with high BVDV-antibody titres. In the further three dams without detectable BVDV-antibody titres, we could not ascertain which colostrum has been fed to the calves. BVDV-specific antigen could not be detected in any of the samples from the calves and dams tested. Using the activity of the gamma-glutamyl-transferase, we assumed a sufficient supply with colostrum for the examined calves.The cause for the occurrence of these BNP cases was due to bone marrow depletion.The reason for the bone marrow depletion remained unclear. However, it was obvious that the BNP described here is highly likely caused by colostrum from cows with positive BVDV-antibody titres.