Bracken poisoning and enzootic haematuria in cattle in China.

Acute bracken poisoning and enzootic haematuria are believed to have occurred in cattle in China for a long time. It is only in the past 10 years, however, that these diseases associated with the consumption of bracken ferns have been studied in detail and this paper reviews these recent studies. Based on a large scale survey, both conditions were found to be serious problems with a wide geographical distribution, especially in the mountainous regions of southwest China. Epidemiological and experimental work revealed that two species of bracken ferns, Pteridium aquilinum and Pteridium revolutum, were associated with these diseases, but the latter seems more important in China.     

Aetiology of enzootic haematuria

The precise aetiology of enzootic haematuria in cattle remains unknown. The involvement of bracken fern (Pteridium aquilinium) appears certain because of the close association between bracken fern infested farms and enzootic haematuria. Several toxic principles have been identified but the main carcinogenic element remains to be conclusively demonstrated. More recently, bovine papilloma virus has been implicated in the aetiology of enzootic haematuria. Its possible interaction with bracken fern carcinogen is discussed.     

Flow cytometric detection of bovine viral diarrhea virus in peripheral blood leukocytes of persistently infected cattle.

Flow cytometry was investigated for detection of bovine viral diarrhea virus (BVDV) in peripheral blood mononuclear leukocytes of persistently infected cattle. The mononuclear leukocytes were purified by sedimentation in a gradient of Ficoll-Paque, fixed, permeabilized, and then labelled by indirect immunofluorescence using biotinylated immunoglobulins from a porcine antiserum to BVDV. Flow cytometric analysis of blood samples obtained from persistently infected cattle revealed virus in 3.0-21.0% (mean +/- SD, 11.2% +/- 6.4%) of the mononuclear leukocytes. Fluorescent cells were not observed in controls. Flow cytometric detection of BVDV in blood cells of persistently infected bovines is a rapid and objective technique which does not require cell culture facilities.     

Scanning electron microscopic study of bovine leukemic cells

Scanning electron microscopic observation of (i) leukemic cells in peripheral blood and tumor tissues of 11 cattle with bovine leukosis (adult form, n = 5; calf form, n = 2; and thymic form, n = 4) and (ii) peripheral lymphocytes from 2 cattle with persistent lymphocytosis and from 3 healthy cattle revealed morphologic differences of cell surface structures among various forms of bovine leukosis. These differences indicated an interrelationship of cell surface morphologic features between peripheral lymphocytes and tumor cells. Leukemic cells from cattle with the thymic and calf forms characteristically had a smooth surface. In cells from cattle with the adult form, the majority of abnormal cells in the peripheral blood, possessed numerous elongated microvilli on the cell surface, whereas tumor cells in the tissue were pleomorphic with a long villous, plicated surface or had stubby projections. Most of the peripheral lymphocytes from cattle with persistent lymphocytosis were characterized by a dense arrangement of elongated microvilli on the cell surface.     

Vascular lesions in lungs of Bali cattle with Jembrana disease.

Jembrana disease is an acute infectious disease of unknown etiology enzootic among Bali cattle (Bos javanicus) in Indonesia. Morphologic examination of 75 female Bali cattle between 18 months and 4 years old affected with Jembrana disease consistently revealed pulmonary granulomatous vascular lesions. The lesions were diffusely distributed throughout the lung. The principal lesion was the presence of a large number of intravascular macrophages that filled the lumina of pulmonary veins and pulmonary arteries of a vascular diameter of 20-200 microns, excluding the rest of blood cellular components. Concentric layers of perithelial cells also with plasma cells and macrophages were occasionally present around both veins and arteries. Infiltration of polymorphonuclear leukocytes or small lymphocytes was not seen. Destruction or necrosis of tissues or blood vessels was rarely seen. Because this vascular lesion was found in the lungs of all affected cattle examined, this change is useful for the postmortem diagnosis of Jembrana disease. Moreover, its presence could be used to distinguish Jembrana disease from malignant catarrhal fever and other lymphoreticular proliferative conditions that are frequently found among cattle in Indonesia.     

Idiopathic renal haematuria in an Egyptian Arabian stallion

A 17-year-old Egyptian Arabian stallion was presented for haematuria and blood clots in the urine of 4 days’ duration. During micturition, haematuria was noted mid-stream with passage of blood clots occurring at the end of urination. Physical examination findings were unremarkable aside from pale mucous membranes. Cystoscopic examination revealed intermittent passage of frank blood (with clots) from the left ureteral orifice compared to grossly normal-appearing urine issuing from the right ureteral orifice. Transcutaneous ultrasonographic evaluation of the right kidney yielded normal findings while the left kidney exhibited pyelectasia, a decreased cortico-medullary ratio, and markedly increased echogenicity of the renal pelvis. Diagnosis of idiopathic renal haematuria was confirmed at necropsy.     

Decreased blood cell counts were not observed in cattle living in the “difficult‐to‐return zone” of the Fukushima nuclear accident

White blood cells, especially lymphocytes, are susceptible to radiation exposure. In the present study, red blood cell, total white blood cell, and lymphocyte counts were repeatedly measured in cattle living on three farms located in the “difficult‐to‐return zone” of the Fukushima nuclear accident, and compared with two control groups from unaffected areas. Blood cell counts differed significantly between the two control groups, although almost all the values fell within the normal range. The blood cell counts of the cattle in the “difficult‐to‐return zone” varied across sampling times even on the same farms, being sometimes higher or lower than either of the two control groups. However, neither a statistically significant decrease in blood cell counts nor an increase in the rate of cattle with extremely low blood cell counts was observed overall. The estimated cumulative exposure dose for the cattle on the most contaminated farm was within a range of 500–1000 mSv, exceeding the threshold for the lymphopenia. Because of the low dose rate on these farms, potential radiation damages would have been repaired and have not accumulated enough to cause deterministic effects.     

Association of bovine papillomavirus type 2 (BPV-2) and urinary bladder tumours in cattle from the Azores archipelago

Urinary bladder tumours in cattle are caused by chronic ingestion of bracken fern and BPV-1/2 infection. The objective of the present study was to assess if BPV-2 was present in urinary bladder lesions from cattle with chronic enzootic haematuria (CEH) from the Azores archipelago (Portugal), in order to gain further information regarding the epidemiologic distribution of this virus. Samples were analysed using PCR specific primers for BPV-2 DNA and an immunohistochemistry for BPV E5 oncoprotein detection. We found a 28% incidence rate of BPV-2 DNA in different types of tumours and cystitis cases (13 out of 46 samples). Tested positive samples for PCR were also positive for the viral E5 oncoprotein; protein immunolabeling was mainly detected within the cytoplasm of urothelial cells, displaying a juxtanuclear distribution. This is the first report of BPV-2 detection in urinary bladder tumours associated with CEH in cattle from the Azores archipelago.     

Common occurrence of a unique Cryptosporidium ryanae variant in zebu cattle and water buffaloes in the buffer zone of the Chitwan National Park, Nepal

There are very few studies on the diversity and public health significance of Cryptosporidium species in zebu cattle and water buffaloes in developing countries. In this study, PCR-restriction fragment length polymorphism and DNA sequence analyses of the small-subunit (SSU) rRNA gene were used to genotype Cryptosporidium specimens from 12 zebu cattle calves, 16 water buffalo calves, and four swamp deer (Cervus duvaucelii) collected from the buffer zone of the Chitwan National Park, Nepal. All Cryptosporidium specimens from cattle and buffaloes belonged to Cryptosporidium ryanae, whereas those from deer belonged to Cryptosporidium ubiquitum. Comparison of the SSU rRNA gene sequences obtained with those from earlier studies has identified a nucleotide substitution unique to all C. ryanae isolates from Nepal, in addition to some sequence heterogeneity among different copies of the gene. The finding of the dominance of a unique C. ryanae variant in both zebu cattle and water buffaloes in Nepal indicates that there is unique cryptosporidiosis transmission in bovine animals in the study area, and cross-species transmission of some Cryptosporidium spp. can occur between related animal species sharing the same habitats.     

Localization of putative pituitary stem/progenitor cells in female dairy cattle

Research on sex-determining region Y-box 2 (SOX2)-positive pituitary stem/progenitor cells, as a source of hormone-producing cells, is progressing rapidly in rodents. However, the stem/progenitor cells supplying hormone-producing cells that are essential for growth, reproduction, and lactation in bovines have not yet been identified. In this study, we characterized SOX2-positive cells in the pituitary gland of dairy cattle (Holstein heifers) after sexual maturity. Immunofluorescence analysis revealed that the localization pattern of SOX2-positive cells in the dairy cattle pituitary gland was similar to that observed in the rodent pituitary gland; the marginal cell layer (MCL), dense cell clusters, and single cells scattered in the parenchyma of the anterior lobe. Furthermore, most of the SOX2-positive cells were positive for the pituitary stem/progenitor cell niche markers E-cadherin and cytokeratin 8+18, which have been reported in rodents. In addition, in the MCL of the anterior lobe, there was a subpopulation of SOX2-positive cells positive for paired-related homeobox 1 and 2, whereas negative for S100β. Moreover, in the parenchyma of the anterior lobe, co-localization of SOX2 and pituitary hormones was infrequent. In summary, this study reveals the localization of putative pituitary stem/progenitor cells positive for SOX2 in dairy cattle. These results provide valuable information to support further investigation of cell supply in the dairy cattle pituitary gland.     

BOVINE ENZOOTIC HAEMATURIA IN QUEENSLAND

Bovine enzootic haematuria was diagnosed in Queensland in coastal areas in association with bracken fern (Pteridium esculentum) on 3 properties or with mulga fern or rock fern (Cheilanthes sieberi) on 4 properties, and in inland areas in association with C. sieberi on 3 properties. In the absence of bracken fern, long-term ingestion of C. sieberi is suggested as a cause of bovine enzootic haematuria. Haemangiomas, haemangiosarcomas, transitional cell carcinomas, papillomas, fibromas and an adenoma were detected in the urinary bladders of 19 affected cattle and were accompanied by chronic cystitis.     

The early events of infection with Theileria parva in cattle: infectivity for cattle of leukocytes incubated in vitro with sporozoites

Leukocytes were isolated from bovine blood and, after short periods of incubation in vitro with sporozoites of Theileria parva, were washed thoroughly, and their infectivity tested in autologous and allogeneic hosts. Using a standard inoculum of 10(6) viable cells, it was found that, after incubation in vitro for either 1 or 24 h, the cells initiated lethal infections in autologous cattle, but failed to infect allogeneic animals. Autologous and allogeneic erythrocytes and mouse lymphocytes similarly incubated with sporozoites failed to infect cattle. The supernatant from bovine lymphocyte suspensions incubated with sporozoites for 1 h produced lethal infections whereas after 24 h of incubation the supernatant was non-infective. All cattle which did not develop detectable infection were fully susceptible to subsequent challenge with a stabilate of sporozoites. By inoculating cattle with graded doses of autologous blood leukocytes which had been incubated for 24 h with sporozoites, it was found that as few as 2 X 10(3) cells gave rise to infection. The results indicate that this approach can be used to evaluate different cell populations as targets for infection and transformation by sporozoites of T. parva.     

Surface markers for characterisation of bovine blood lymphocyte populations and changes in these from birth to maturity

A sheep erythrocyte (E) rosette technique was developed for use with cattle lymphocytes. This involved the use of 17 per cent Ficoll 400 and preservative-free heparin (84 iu/ml) in the saline-erythrocyte mixture. Using this technique, 83 per cent of peripheral blood lymphocytes in cattle aged between six and 10 years were found to form E rosettes. The remaining cells (17 per cent) were B-cells, so that no cells remained unmarked. Lymphocytes from very young calves contained a population of unmarked or null cells, but these rapidly diminished as the animals matured. A peak of total lymphocytes recovered from blood, as well as E rosette-forming cells, occurred in calves aged four to six months. The non-E rosette-forming cells were mostly B-cells and it was suggested that this was associated with calf weaning. The total number of lymphocytes recovered, as well as E rosette-forming cells, gradually fell with the age of the cattle sampled. Null cells were virtually absent from the blood of cattle six years and older. Bovine T-cells could be further subdivided into Fc mu, Fc gamma and C' receptor-bearing subpopulations on the basis of overlap with R rosette-forming cells. Some further separation of these cells from B-cells was achieved using density gradient centrifugation on Percoll. Separation of E rosette-forming cells with Fc receptors from E rosette-forming cells without Fc receptors was achieved by nylon wool columns, to which the Fc receptor bearing cells were adherent. It was concluded that bovine blood lymphocytes had blood T-lymphocyte populations with markers which may correspond to the 'helper' (Fc mu ) and 'suppressor' (Fc gamma ) populations described for the human.     

Induction of the 68 kDa major heat-shock protein in different Theileria annulata- and virus-transformed bovine lymphoblastoid cell lines.

Expression of the major inducible heat-shock protein of 68 kDa (hsp68) has been analyzed in peripheral blood mononuclear cells (PBMC) from cattle and in six Theileria annulata- and two bovine leukemia virus-transformed bovine lymphoblastoid cell lines (BoLCL). By metabolic labeling, hsp68 could be detected in PBMC and BoLCL only after heat-shock, but not under normal culture conditions. Immunoblot analysis with an hsp68 reactive monoclonal antibody similarly revealed a strong hsp68 response after heat-shock in BoLCL, and no hsp68 expression under normal culture conditions. Normally kept PBMC, however, were weakly positive with the antibody. The data are discussed with respect to the constitutive expression of hsp68 seen in several other cell lines.     

Resection cystoplasty of a squamous cell carcinoma in a mare

A 22‐year‐old Arabian mare was examined for evaluation of haematuria of 2 months' duration. Complete blood cell count and chemistry revealed anaemia of chronic disease (i.e. normocytic, normochromic) and hypoproteinaemia. Cystoscopy revealed a haemorrhagic mass protruding into the lumen of the urinary bladder in the apical region. The mass was surgically removed by partial cystectomy performed through a caudal ventral midline laparotomy. Histological examination of the mass confirmed the diagnosis of squamous cell carcinoma. Tumours of the equine urinary bladder are rare, and when a partial cystectomy is indicated, a caudal ventral midline laparotomy may provide adequate surgical exposure even in adult horses.     

Changes in B cell and T cell subsets in bovine leukaemia virus-infected cattle

Direct immunofluorescence and fluorescence-activated cell sorter techniques were used for the detection of surface immunoglobulin positive (SIg+) cells in peripheral blood lymphocytes (PBL's) of bovine leukaemia virus (BLV) infected cattle with or without persistent lymphocytosis (PL+, PL-) and in BLV-free cattle. The percentage of SIg+ cells was more than twice as high in BLV+PL+ cattle than in BLV-free and BLV+PL- cattle. Bovine T cells, and T cell subsets were identified indirectly by the same techniques using three monoclonal antibodies (MAb's) specific for all T cells (IL-A43), T helper (BoT4) cells (IL-A12) and T cytotoxic (BoT8) cells (IL-A17). The major histocompatibility complex (MHC) determinants of both class II (BoT4) and class I (BoT8) as well as all T cells were significantly reduced in BLV+PL+ compared to BLV-free cattle. The actual decrease in the BoT8 cell subset or the dilution effect that would change effector:target cell ratio suggests that a resultant decrease in cytotoxic activity in BLV+PL+ cattle may play an important role in the progress of BLV infection in cattle.     

Use of molecular markers for the identification of River Buffalo chromosomes: chromosome one

A standard karyotype for the River Buffalo has recently been established. The largest five chromosomes are biarmed and, based on the banding homology between cattle and buffalo chromosomes, were suggested to originate from the fusion of cattle acrocentric chromosomes. The origin of buffalo chromosome 1 is controversial due to the difficulty in differentiating between the small acrocentric cattle chromosomes. Using molecular markers assigned to cattle chromosomes, synteny between CD18, a marker for BTA1, and markers for small acrocentric cattle chromosomes BTA 24 to BTA 29 was investigated in buffalo/hamster somatic cell hybrids. The investigation revealed that CD18 is syntenic with ANT1, a marker for cattle chromosome 27. The present results confirm that buffalo BBU1 results from fusion of cattle BTA 1 and BTA 27. They also underline the importance of biarmed buffalo chromosomes for the identification of small cattle acrocentrics.     

德系西门塔尔牛与荷斯坦牛及其杂种后代血液生理生化指标的比较分析

为探究德系西门塔尔牛、荷斯坦牛及其杂交后代血液生理生化指标状况及差异,选择5月龄、体重150~200 kg的健康公牛15头,其中荷斯坦公牛、西×荷杂种一代公牛(简称西荷杂种牛)、德系西门塔尔公牛各5头,育肥372 d后屠宰测定其各项血液生理生化指标。结果显示:德系西门塔尔牛红细胞、血红蛋白、红细胞压积均显著高于其他两组牛(P<0.01),白细胞、中性细胞数、中性细胞比率、嗜碱性粒细胞比率处于居中水平;荷斯坦牛白细胞、红细胞平均体积均显著高于其他两组牛(P<0.05),中性细胞数、中性细胞比率极显著高于其他两组牛(P<0.01),嗜碱性粒细胞比率则极显著低于其他两组牛(P<0.01);西荷杂种牛白细胞、游离甲状腺素、皮质醇均显著低于其他两组牛(P<0.05),淋巴细胞数、淋巴细胞比率、嗜酸性粒细胞比率、嗜碱性粒细胞数、嗜碱性粒细胞比率均极显著高于其他两组牛(P<0.01),血小板压积显著高于其他两组牛(P<0.05)。在血液生化指标方面,荷斯坦牛血清钾离子显著低于其他两组牛(P<0.05),德系西门塔尔牛游离甲状腺素浓度显著高于其他两组牛(P<0.05),荷斯坦牛皮质醇浓度显著高于其他两组牛(P<0.05),其他血液生理生化指标在3组间比较差异均不显著(P>0.05)。综上说明,西荷杂种牛抗病力和抗逆性较强,德系西门塔尔牛代谢旺盛,环境适应性强。