Serum hepatitis associated with commercial plasma transfusion in horses

This report describes 4 fatal cases of serum hepatitis associated with the administration of commercial plasma in the horse. Serum hepatitis in the horse is characterized by acute hepatic central lobular necrosis, and it has been associated with the administration of biological products of equine origin. None of these horses had a recent history of equine biologic-origin vaccination; however, they had received 1.5-5 L of commercial plasma, and in I horse, an additional 8 L of fresh blood. Acute, severe colic unresponsive to medical therapy, lethargy, or sudden death developed in these 4 horses 41 to 60 days later. Two of the horses developed encephalopathy, confirmed in 1 horse by the presence of severe diffuse Alzheimer type II astrocytes in the brain. Although the prevalence of serum hepatitis associated with the administration of commercial plasma appears to be low in the horse, it should be considered an uncommon but potentially fatal risk factor.     

Effect of vitamin D3 supplementation level on the postmortem tenderization of beef from steers

The objective of this experiment was to determine the effect of different doses of vitamin D3 (VITD) on beef feedlot performance, plasma and muscle Ca2+, tissue residues, and improvement of Warner-Bratzler shear force (WBS) and panel tenderness. A total of 167 steers were fed one of six levels of VITD. The VITD treatments (28 steers/treatment) were 0, 0.5 x 10(6), 1 x 10(6), 2.5 x 10(6), 5 x 10(6), and 7.5 x 10(6) IU/steer daily of VITD fed nine consecutive days before slaughter. Feedlot performance and plasma Ca2+ were measured during the last 21 days on feed. Warner-Bratzler shear force was measured on strip loin and top round steaks at 7, 10, 14, and 21 d postmortem. The VITD treatments of 5 and 7.5 x 10(6) IU/steer daily decreased (P < 0.05) ADG, and VITD supplementation of 2.5, 5, and 7.5 x 10(6) IU/steer daily decreased average dry matter feed intake (P < 0.05) at the end of the feeding trial. Plasma Ca2+ increased linearly with VITD treatment (P < 0.01). Calpastatin and calpain activity were not influenced by treatment (P > 0.05), but muscle Ca2+ was increased (P < 0.05) by VITD treatments of 1, 2.5, 5, and 7.5 10(6) IU/steer daily. Feeding VITD did not influence (P > 0.05) carcass quality or yield traits. Supplementing VITD at levels of 1, 2.5, 5, and 7.5 10(6) IU/steer daily increased (P < 0.05) VITD concentrations in strip loin and liver samples. Cooking liver decreased VITD concentrations 10 to 28%. Vitamin D3 treatments of 0.5 and 7.5 x 10(6) IU/d reduced strip loin steak WBS at d 7 (P < 0.05), but VITD treatments did not decrease strip loin steak WBS at any other time postmortem. The VITD treatments of 0.5, 1, and 5 x 10(6) IU/steer daily decreased top round steak WBS at 7 d, and all VITD treatments decreased 10-d top round steak WBS (P < 0.05). Supplementing steers with 0.5 x 10(6) IU/steer daily of VITD also decreased (P < 0.05) top round steak WBS at 21 d postmortem compared with controls. Sensory tenderness at 7 d postmortem was increased (P < 0.05) by all VITD treatments in top round steaks, yet strip loin tenderness scores were not affected (P > 0.05) by VITD treatment. Treatment with VITD quadratically decreased (P < 0.05) round WBS. Thus, VITD treatment will effectively improve tenderness when cattle tend to be tough and have no impact on cattle that produce tender beef. Feeding steers 0.5 x 10(6) IU of VITD daily for 9 d improved tenderness in two muscles without negatively affecting feedlot performance or tissue residues.     

Analysis of the repertoire of cattle CD4(+) T cells reactive with bovine viral diarrhoea virus

Cell-mediated immunity and CD4(+) cells in particular are important for the resolution of acute infection with non-cytopathic bovine viral diarrhoea virus (BVDV). CD4(+) T cells were shown to recognise virus-infected and non-infectious-protein-pulsed APCs, whereas CD8(+) T cells recognised only virus-infected APCs. T cell recognition was strain cross-reactive and MHC-restricted. Using native and recombinant antigens, we identified the structural glycoprotein E2 and the non-structural protein NS3 as dominant CD4(+) T cell determinants. The repertoire of CD4(+) T cell responses to E2 and NS3 was examined using inbred, homozygous cattle and overlapping synthetic peptides. The repertoire was biased toward conserved regions of NS3 and excluded the hypervariable regions of E2. The number of peptides that were recognised varied between animals but patterns could be distinguished in those animals that shared the same DRB3(*) allele. Of particular interest were: (i) a determinant that was recognised in the context of both DRB3(*) alleles (i.e. DRB3(*)2002 and DRB3(*)0701), (ii) two determinants that were juxtaposed to B cell sites, and (iii) a determinant that had structural analogy with a NS3 epitope previously described for the closely related hepatitis C virus. The minimum stimulatory sequence of the latter, NS3(397-414), was located to residues NS3(400-410).     

PERSISTENT NEPHROGRAM IN A CAT AFTER INTRAVENOUS UROGRAPHY

An 8-year-old cat was evaluated for recurrent bouts of stranguria, hematuria and pollakiuria. Routine urinalysis, CBC and serum chemistries were unremarkable. Intravenous excretory urography was performed while the cat was sedated. The nephrogram was initially well opacified and increased in opacity during the 40 minutes that the study was performed. Ureterogram and pyelogram failed to develop. Oliguria with little excretion of the contrast medium was documented. These findings are consistent with either contrast medium associated hypotension or acute renal failure. Treatment with aggressive fluid therapy and a continuous dobutamine infusion reestablished urine output after 2 hours.     

Evaluation of conventional and radiometric fecal culture and a commercial DNA probe for diagnosis of Mycobacterium paratuberculosis infections in cattle.

Radiometric (RCM) and conventional fecal culture (HEY) and a commercial polymerase chain reaction/DNA probe were evaluated as diagnostic tests for subclinical paratuberculosis in dairy cattle using fecal specimens from a repository of paratuberculosis specimens. The case definition of subclinical bovine paratuberculosis was isolation of Mycobacterium paratuberculosis, by conventional or radiometric culture, from fecal samples or internal organs of dairy cattle without diarrhea or chronic weight loss. Animals designated as free of the disease originated exclusively from certified paratuberculosis-free herds in Wisconsin. Among 182 infected cattle, RCM and HEY fecal culture and the DNA probe had test sensitivities of 54.4%, 45.1% and 33.5%, respectively. Fecal samples from only 111 of the M. paratuberculosis-infected cows tested positive by at least one of the three tests and these cows were designated as fecal shedders; the remaining 71 were considered to have prepatent infections. Among the 111 M. paratuberculosis fecal shedders, RCM, HEY and the probe detected the organism in 89.2%, 73.8% and 55.0% of the fecal specimens, respectively. Herd prevalence significantly affected the sensitivity of all three diagnostic tests (p less than 0.05) but only affected the fecal shedder detection efficiency of the DNA probe (p less than 0.01). No positive DNA probe results were found on 100 randomly selected fecal samples from cows in four certified paratuberculosis-free herds, thus the DNA probe was 100% specific. Probe analyses could be performed in 24 h or less. Time to complete the culture-based tests was 12 wk for HEY and 7 wk for RCM.(ABSTRACT TRUNCATED AT 250 WORDS)     

Malignant granulosa-theca cell tumor in a two-year-old Miniature Horse.

A 2-year-old female Miniature Horse that presented with a history of progressive weight loss, depression, and diarrhea was diagnosed at necropsy with a highly malignant abdominal neoplasm involving the left ovary, kidneys, adrenal glands, intestines, and various abdominal and thoracic lymph nodes. Microscopic examination of these masses revealed large pleomorphic cells that stained positive for vimentin and inhibin and negative for epithelial membrane antigen and placental alkaline phosphatase. Ultrastructural examination of the cells revealed a high nucleocytoplasmic ratio and indented euchromatic nuclei with large nucleoli. Based on the gross, microscopic, immunohistochemical, and ultrastructural features, the neoplasm was identified as a malignant granulosa-theca cell tumor, a rare neoplasm in young horses.     

Volcanic activity and great earthquakes at convergent plate margins

Volcanoes are unusually quiet for periods of a few years to a few decades prior to great shallow-thrust earthquakes. This is the most obvious part of an apparent pattern of volcanic activity related to the occurrence of great earthquakes at some convergent plate margins.