Electron microscopic studies on conjunctiva associated lymphoid tissue (CALT) in Angora goats

The purpose of this study was to investigate the electron microscopic structure of conjunctiva associated lymphoid tissue (CALT) and to determine the uptake of macromolecules from follicle associated epithelium (FAE) of Angora goats. The sample tissues taken from lower and upper eyelids of ten 5-6 month-old healthy Angora goats were used in this study. The conjunctiva associated lymphoid tissue of Angora goats was formed by solitary or aggregate lymphoid follicle and follicle associated epithelium which cover these follicle. FAE was formed by flattened epithelial cells, lymphocytes, monocytes and polymorph nuclear leukocytes but no goblet cells. Ferritin particles were seen on the apical surface, in the invaginations, vesicles, vacuoles of flattened epithelial cells. It was concluded that these epithelial cells were specialized to uptake macromolecules.     

Differential acute phase immune responses by Angus and Romosinuano steers following an endotoxin challenge

Our primary objective of this experiment was to evaluate potential genetic differences between two diverse Bos taurus breeds [Angus (AG) and Romosinuano (RO)] in response to an endotoxin challenge. Eighteen steers (n = 9 steers/breed; 299.4 ± 5.2 kg BW) were acclimated to environmentally controlled chambers maintained at thermoneutrality (19.7 °C) and then fitted with indwelling jugular catheters and rectal temperature (RT) recording devices 1 d before the endotoxin challenge. The next day, blood samples were collected at 30-min intervals from −2 to 8 h, and RT was measured continuously at 1-min intervals throughout the study. At time 0, all steers received an intravenous bolus injection of lipopolysaccharide (LPS; 2.5 μg/kg BW). Serum samples were stored at −80 °C until analyzed for cortisol, proinflammatory cytokines [tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), IL-6, and interferon gamma (IFN-γ)], and acute phase proteins (serum amyloid A, acid soluble protein, ceruloplasmin, and α-acid glycoprotein). Rectal temperatures increased in both breeds within 1 h after LPS, with RO producing a greater increase in RT than AG steers (P < 0.001). Serum cortisol and TNF-α increased (P < 0.01) in both breeds within 1 h after the LPS challenge. For cortisol, an overall breed effect (P < 0.02) was detected, such that AG steers had a higher cortisol response than RO steers. A breed × time interaction (P < 0.01) was observed for TNF-α, such that the response was delayed and extended in the RO steers compared with the AG steers. At 2 and 2.5 h after LPS, TNF-α concentrations were greater (P < 0.03) in RO steers than in AG steers. For IL-1β, a breed × time interaction (P < 0.04) was also observed. At 3 h after LPS, IL-1β concentrations were greater (P < 0.01) in RO steers than in AG steers. Serum IL-6 and IFN-γ increased (P < 0.01) in a similar manner in both groups after the LPS challenge. These data show differences in the innate immune response between two diverse Bos taurus breeds which may provide insight about differences observed in productivity, heat tolerance, disease resistance, and longevity among cattle breeds.     

Luteinizing hormone-dependent Cushing's syndrome in a pet ferret (Mustela putorius furo)

Hyperadrenocorticism in ferrets is associated with increased circulating concentrations of adrenal androgens, whereas plasma concentrations of cortisol and ACTH are usually not affected. Here, we report on a 5-year-old castrated male pet ferret (Mustela putorius furo) in which the major presenting signs were polyuria and polyphagia. Routine biochemistry values were within their reference ranges. The urinary corticoid:creatinine ratio (UCCR) was increased and the plasma ACTH concentration was suppressed. Abdominal ultrasonography revealed an enlarged right adrenal gland and atrophy of the left adrenal gland. Administration of hCG resulted in an increase of plasma cortisol and androstenedione concentrations. Based on these findings LH/hCG-dependent hypercortisolism and hyperandrogenism were suspected and treatment was started with a depot GnRH-agonist implant containing 9.4mg deslorelin. Within 3 weeks after placement of the implant all clinical signs had disappeared. Three months later the endocrine parameters had normalized, while abdominal ultrasonography revealed that the right adrenal gland had diminished in size and the left adrenal gland was considered of normal size. No recurrences of clinical signs were seen within 2 years after placement of the deslorelin implant. At that time urinary corticoid and plasma hormone concentrations were within their reference ranges, and no further change in the size of the adrenal glands was seen. In conclusion, this is the first confirmed case of LH-dependent hypercortisolism in a ferret that was treated successfully with a depot GnRH-agonist.     

Epiphyseal cartilage canal blood supply to the tarsus of foals and relationship to osteochondrosis

REASON FOR PERFORMING STUDY: Pathological changes in the blood supply to growth cartilage have been implicated in the pathogenesis of osteochondrosis (OC) in horses, but have not been reported using vascular perfusion techniques. OBJECTIVE: To describe the developmental pattern of cartilage canal vessels in the distal tibial epiphysis and talar growth cartilage of foals. METHODS: Nine foals bred from parents with OC were sacrificed between the ages of 0 and 7 weeks to undergo a barium perfusion procedure. The distal end of the tibia and the entire talus were cleared in methyl salicylate and perfused vessels studied in the intact bones. Slabs with a thickness of 4-5 mm from 3 predilection sites for OC were examined in the stereomicroscope and with light microscopy. RESULTS: Cartilage canals were present for a limited period of growth. Perfused vessels initially entered canals from the perichondrium. Vessels in the proximal portion of canals retained their perichondrial arterial source throughout. With time, the ossification front advanced to incorporate the mid-portion of canals; and anastomoses formed between canal vessels and subchondral vessels. A shift occurred and vessels in the distal terminus of canals came to use subchondral vessels as their arterial source. Twelve histological lesions were found in 7 foals. All contained necrotic vessels surrounded by necrotic growth cartilage and 3 caused macroscopically visible delay in endochondral ossification. Lesions were located where vessels traversed the ossification front to enter the distal terminus of canals. CONCLUSION: Cartilage canal vessels are particularly susceptible to failure at the point where they cross the ossification front, with consequences for the viability of those chondrocytes that depend on them. POTENTIAL RELEVANCE: A better understanding of how lesions of OC arise may improve the ability to identify, monitor, prevent and treat this disorder. Involvement of cartilage canals in the pathogenesis of equine tarsal OC plausibly explains several clinical features of this disease.     

First report of Cryptosporidium deer-like genotype in Malaysian cattle

Fifty faecal samples from diarrheic calves between 1 and 6 months old were collected per rectum from 5 farms around Petaling District in Selangor, Malaysia for Cryptosporidium species detection and genotyping investigation. Oocysts were purified using sedimentation and gradient centrifugation, then examined by immunofluorescence assay (IFAT). Genomic DNA was extracted from all samples and nested PCR was performed to amplify the SSU rRNA gene. Eighteen samples (36%) were positive for Cryptosporidium species by PCR. The sequence and phylogenetic analysis of 14 isolates indicated that Cryptosporidium parvum was most common (11 isolates) followed by Cryptosporidium deer-like genotype (3 isolates). The present work reports the first data on Cryptosporidium genotyping from cattle in Malaysia.     

Outcome of cats with low-grade lymphocytic lymphoma: 41 cases (1995-2005)

OBJECTIVE: To evaluate factors associated with response to treatment, remission duration, and survival in cats with low-grade lymphoma affecting various organ systems. DESIGN: Retrospective case series. Sample POPULATION: 41 cats with histologically confirmed low-grade lymphocytic lymphoma. PROCEDURES: Medical records and biopsy specimens of cats with histologically confirmed low-grade lymphocytic lymphoma of various organ systems treated with prednisone and chlorambucil between 1995 and 2005 were reviewed. The Kaplan-Meier method was used to estimate remission duration and survival. Factors potentially associated with prognosis were compared. RESULTS: Common clinical signs were weight loss (83%), vomiting (73%), anorexia (66%), and diarrhea (58%). Seventy-eight percent of cats tested had low serum cobalamin concentrations. Lymphoma was confined to the gastrointestinal tract in 68% of cats. Fifty-six percent of cats achieved a complete response to treatment, and 39% achieved a partial response. Five percent of cats had no response. No association was found between any risk factors (including anatomic site) and response to treatment. Partial response was associated with shorter remission duration, compared with complete response; median remission duration was 428 days for cats achieving a partial response, compared with 897 days for cats achieving a complete response. No other factors were associated with remission duration. Overall median survival time was 704 days. No factors were significantly associated with survival time. CONCLUSIONS AND CLINICAL RELEVANCE: Most cats with lymphocytic lymphoma responded to treatment with prednisone and chlorambucil, and most factors evaluated were not associated with outcome.     

Economic effect of pneumonia and pleurisy in lambs in New Zealand

AIM: To estimate the cost of pneumonia and pleurisy in lambs to the sheep industry in New Zealand, in order to provide a reference for future cost-benefit calculations for control programmes to reduce the incidence of pneumonia. METHODS: An estimate of the economic cost of pneumonia and pleurisy in lambs was based on: cohort studies of the association between growth rate and the extent of pneumonic lesions at slaughter (n=14 flocks), the prevalence of moderate to severe (MS) pneumonia (> or =10% lung surface area affected) and pleurisy (n=1,719 flocks), the correlation between the prevalence of MS pneumonia and economic loss at the flock level, and data on annual slaughter statistics and carcass value in New Zealand. A stochastic spreadsheet model was developed and run with 1,000 iterations. Input variables represented by probability distributions were growth rate, average cost of loss according to the prevalence of pneumonia per month, carcass value, prevalence of pleurisy, and carcasses downgraded for pleurisy, and annual national slaughter statistics. The output was a posterior distribution of the annual cost of disease. RESULTS: The cost of pneumonia only included the loss associated with reduced growth rate, while mortality due to pneumonia was assumed to be low and was ignored. The cost of pleurisy included the loss associated with downgraded or condemned carcasses. Thus, the simulated annual average cost of pneumonia was NZ$28.1 (95% CI=NZ$15.0-42.0) million, and that of pleurisy NZ$25.1 (95% CI=NZ$10.2-48.1) million. The combined cost of pneumonia and pleurisy averaged NZ$53.2 (95% CI=NZ$32.4-78.9) million. The parameters with the greatest impact on the combined cost of pneumonia and pleurisy were prevalence of pleurisy between March and May, and cost of reduced growth due to pneumonia for lambs slaughtered in June. CONCLUSIONS: The average cost of pneumonia and pleurisy to the sheep industry in New Zealand due to reduced lamb growth and decreased carcass value is likely to be between NZ$32.4 and $78.9 million. This is a conservative estimate, omitting mortalities, indicating that pneumonia and pleurisy have substantial economic impact on sheep farming in New Zealand. Considering that 23,833,000 lambs were slaughtered in 2003/2004 (average value $65.56/lamb), this cost would equate to NZ$1.36-3.31 per lamb. CLINICAL RELEVANCE: Pneumonia and pleurisy are common diseases in lambs in New Zealand, leading to substantial economic loss to producers.     

Immunohistochemical studies on the splenic lobe of the pancreas in young Japanese quails (Coturnix c. japonica)

The splenic lobe (Lobus splenicus) of the pancreas of young meat-type quails (Coturnix c. japonica) was examined by immunohistochemical and light microscopic methods. The endocrine cells are mainly grouped as alpha, beta and mixed islets. A large region consisting of alpha cells is located in the central region of the splenic lobe whereas numerous beta islets are detected in the periphery of the splenic lobe. Alpha islets are in the majority composed of toluidine blue positive A cells and a few toluidine blue negative D and / or avian pancreatic polypeptide (APP) endocrine cells. Beta islets contain only a few toluidine blue negative B and a few D cells. Immunohistochemical staining of the splenic lobe reveal in the centre of beta islets numerous insulin immunoreactive cells and scarcely in alpha islets, exocrine tissue and / or among acinar cells. Somatostatin immune-reactive cells form a circular layer in the periphery of beta islets whereas these cells are uniformly distributed throughout the alpha islet parenchyma and exocrine tissue. In conclusion, the morphology but also the endo- and exocrine functions of the splenic lobe of quails are similar to observations in other avian species such as chicken, duck, goose and pigeon.