A defect in thyroglobulin synthesis in an inherited ovine goitre: possible neonatal respiratory distress syndrome

A ram lamb with congenital goitre showed signs of respiratory distress at birth. All previously affected lambs from this flock bad been born dead or bad died soon after birth. The serum free-thyroxine level at 1 birth was low (9.8 pmol/l) but treatment with oral L-thyroxine resulted in an increase in thyroxine blood levels to above normal and regression of the goitre. Four weeks after withdrawal of thyroid supplementation and when the lamb was eight weeks old, the radio iodide uptake mechanism of the thyroid glands was shown to be intact but the iodide was not organified. Low normal peroxidase activity was demonstrated in fresh thyroid tissue but gel electrophoresis demonstrated an absence of normal thyroglobulin from extracts of the goitrous thyroid. This lamb and the other affected lambs of this flock have an inherited defect in thyroglobulin synthesis and it is likely that the respiratory distress was associated with the low levels of thyroid hormone affecting foetal lung development.     

Qualitative and quantitative analysis of uroliths in dogs: definitive determination of chemical type

Effective treatment and prevention of urolithiasis depends on accurate determination of the chemical nature of the uroliths. A widely used qualitative chemical procedure was compared with quantitative crystallographic analysis of 272 canine uroliths. Agreement between the 2 methods was 78%. Qualitative analysis failed to detect 62% of calcium-containing uroliths and 83% of carbonate apatite uroliths. Qualitative analysis gave false-positive results for urates in 55% of cystine uroliths. Mixed uroliths comprising 6% of the total could not be classified without quantitative analysis. Silicate, cystine, and urate uroliths generally were of pure composition. Crystallographic analysis indicated the following distribution of major types: struvite, 69%; calcium oxalate, 10%; urate, 7%; silicate, 3.5%; cystine, 3.2%; calcium phosphate, 1%; and mixed, 6%. Among dogs with struvite uroliths, 66% had positive results of bacterial culturing from the urinary bladder. Six breeds (Miniature Schnauzer, Welsh Corgi, Lhasa Apso, Yorkshire Terrier, Pekingese, and Pug) had a significantly higher risk for urolithiasis, compared with other breeds. The German Shepherd Dog had a significantly lowered risk, compared with other breeds. Two breeds had significant relationship to a specific type of urolith: Miniature Schnauzer for oxalate, and Dalmatian for urate (P less than 0.001). It was concluded that quantitative analysis, using crystallography, was superior for the detection of calcium oxalate, carbonate apatite, cystine, urate, and mixed uroliths.     

Soil type as a putative risk factor of ovine and caprine paratuberculosis seropositivity in Spain

Relationships between soil type and ovine and caprine paratuberculosis in the Avila region (central Spain) were evaluated using data from a cross-sectional study of the most-important diseases of small ruminants in this Spanish region between 1996 and 1997. Questionnaire data from 61 herds (38 ovine and 23 caprine) and 1451 serum samples (1041 ovine and 410 caprine) were used. Herd paratuberculosis (herds were scored as positive to paratuberculosis if any of the serum samples was positive in an agar-gel immunodifussion) was the outcome of interest, whereas soil type in the municipality where farms were located was the predictor variable. Other variables related to soil and soil usage, and herd size, replacement, main food production and animal species were also introduced into the multivariable logistic regression. The final model contained only two independent variables: the predictor variable soil type (coded as two dummy variables ST-1 and ST-2) and herd size (dichotomized at the highest quartile). The estimated Odds Ratios were 25.9 (95% CI: 1.6, 411) for ST-1 (entisols as soil type) and 3.5 (95% CI: 0.3, 45) for ST-2 (inceptisols as soil type).     

Carriage of methicillin-resistant Staphylococcus pseudintermedius in small animal veterinarians: indirect evidence of zoonotic transmission

Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is increasingly reported in small animals and cases of human infections have already been described despite its recent emergence in veterinary practice. We investigated the prevalence of MRSP and methicillin-resistant Staphylococcus aureus (MRSA) among small animal dermatologists attending a national veterinary conference in Italy. Nasal swabs were obtained from 128 veterinarians, seven of which harboured MRSP (n = 5; 3.9%) or MRSA (n = 2; 1.6%). A follow-up study of two carriers revealed that MRSP persisted for at least 1 month in the nasal cavity. Methicillin-susceptible S. aureus (MSSA) was isolated from 32 (25%) conference participants, whereas methicillin-susceptible S. pseudintermedius (MSSP) was not detected, suggesting that MRSP may have a particular ability to colonize humans compared to MSSP. All isolates were characterized by spa typing. Methicillin-resistant isolates were further typed by antimicrobial susceptibility testing, SCCmec and multi-locus sequence typing. Two lineages previously associated with pets were identified among the five MRSP isolates; the European epidemic clone ST71-SCCmec II-III and ST106-SCCmec IV. One of the two MRSA isolates displayed a genotype (ST22- SCCmecIV) frequently reported in dogs and cats. MRSP isolates were resistant to more antimicrobial agents compared with MRSA isolates and displayed the typical multidrug resistance patterns of MRSP in pets. The 32 MSSA isolates belonged to 20 spa types and the most frequent types (t12, t15 and t166) were associated with common S. aureus lineages in humans (CC30 and CC45). Although low, the 3.9% MRSP carriage rate found among small animal dermatologists was surprising in consideration of the rare occurrence of S. pseudintermedius in humans, the lack of MSSP detection and the recent appearance of MRSP in Europe. As cases of human MRSP infection have been linked with pets, veterinarians should be aware of this zoonotic risk and proper preventative measures should be taken to avoid MRSP transmission from animal patients.     

Genetic analysis of a canine calicivirus: evidence for a new clade of animal caliciviruses.

This paper describes the relationship of a canine calicivirus, named No.48, to other human and animal caliciviruses, based on phylogeny of the 3' half of its genome. It was found that No.48 constitutes a unique lineage, most closely related but distinct from feline and San Miguel sea lion caliciviruses.     

The peripheral blood picture: a peephole gives insight into the struggle for survival of the body

The morphological features and fluctuation of cellular components derived from haemograms of a cat infected with toxoplasmosis provide information on the state and activity of important cell systems: the unspecific cellular defense by means of phagocytosis as well as the recruitment and functional stimulation of phagocytizing cells by cytokines and moreover the specific immune reaction, triggered by macrophages, phagocytizing, processing and presenting antigens to immune competent T-cells, inducing an immune response, which finally leads to the formation of antibody-producing plasma cells from B-cells.     

An outbreak of feline infectious peritonitis in a Taiwanese shelter: epidemiologic and molecular evidence for horizontal transmission of a novel type II feline coronavirus

Feline infectious peritonitis (FIP) is a fatal disease caused by feline coronavirus (FCoV) infection. FCoV can be divided into serotypes I and II. The virus that causes FIP (FIPV) is believed to occur sporadically and spread infrequently from cat to cat. Recently, an FIP outbreak from an animal shelter was confirmed in Taiwan. FCoV from all the cats in this shelter were analyzed to determine the epidemiology of this outbreak. Thirteen of 46 (28.2%) cats with typical signs of FIP were identified. Among them, seven cats were confirmed by necropsy and/or histopathological examinations. Despite the fact that more than one FCoV was identified in this multi-cat environment, the eight FIP cats were invariably found to be infected with a type II FCoV. Sequence analysis revealed that the type II FIPV detected from fecal samples, body effusions and granulomatous tissue homogenates from the cats that succumbed to FIP all harbored an identical recombination site in their S gene. Two of the cats that succumbed to FIP were found to harbor an identical nonsense mutation in the 3c gene. Fecal shedding of this type II virus in the effusive form of FIP can be detected up to six days before death. Taken together, our data demonstrate that horizontal transmission of FIPV is possible and that FIP cats can pose a potential risk to other cats living in the same environment.     

Evidence for a potential role of neuropeptide Y in ovine corpus luteum function

Neuropeptide Y (NPY) is a neurohormone that is typically associated with food intake, but it has also been reported to affect the production of progesterone from luteal tissue in vitro. However, NPY has not been previously immunolocalized in the ovine ovary or in the corpus luteum (CL) of any species, and the effects of this neurohormone on luteal function in vivo are not known. Thus, we performed fluorescent immunohistochemistry (IHC) to localize NPY in the ovine ovary and used avidin-biotin immunocytochemistry (ICC) to further define the intracellular localization within follicles and the CL. We then infused NPY directly into the arterial supply of the autotransplanted ovaries of sheep to determine the in vivo effect of exogenous NPY on ovarian blood flow and on the luteal secretion rate of progesterone and oxytocin. Immunohistochemistry revealed that the NPY antigen was localized to cells within the follicles and CL, in the nerve fibers of the ovarian stroma, and in the vessels of the ovarian hilus. In the follicle, the NPY antigen was localized to nerves and vessels within the theca interna layer, and strong staining was observed in the granulosal cells of antral follicles. In the CL, NPY was localized in large luteal cells and in the vascular pericytes and/or endothelial cells of blood vessels, found dispersed throughout the gland and within the luteal capsule. In vivo incremental infusions of NPY at 1, 10, 100, and 1,000 ng/min, each for a 30-min period, into the arterial supply of the transplanted ovary of sheep bearing a CL 11 d of age increased (P ≤ 0.05) ovarian blood flow. The intra-arterial infusions of NPY also increased (P ≤ 0.05) in a dose-dependent manner the secretion rate of oxytocin, which was positively correlated (P ≤ 0.05) with the observed increase in ovarian blood flow. The infusions of NPY had a minimal effect on the secretion rate of progesterone, and similar intra-arterial infusions of NPY into sheep with ovarian transplants bearing a CL over 30 d of age had no significant effect on ovarian blood flow or on the secretion rate of progesterone. These results suggest that NPY acts on the luteal vascular system and the large luteal cells to rapidly stimulate blood flow and the secretion of oxytocin, respectively, which collectively implies a putative role for NPY during the process of luteolysis when increasing amounts of oxytocin are secreted from the ovine CL in response to uterine pulses of prostaglandin F2α.     

Measurement of IgG concentration in ovine fetal fluids: a useful diagnostic test

The Veterinary Diagnostic Laboratory at Oregon State University received 172 aborted ovine fetuses during the 1985-1987 lambing seasons; from 120 of these, body fluids were evaluated for IgG levels. Fifty-two (43%) of the fetal fluids had immunoglobulin G (IgG) levels greater than 15 mg/dl. Forty-five (87%) of the fluids with elevated IgG levels were confirmed or presumed toxoplasma or chlamydia abortions. A mean fetal fluid IgG concentration of 111.5 +/- 78 mg/dl was found for the 26 toxoplasma abortions; for the 19 chlamydia abortions, a mean IgG concentration of 109 +/- 91 mg/dl was found. Antibody titers equal to or greater than 1:40 against Toxoplasma gondii were detected in 23 fetal fluids. Fetal fluid IgG concentration less than 15 mg/dl was found to be associated with bacterial organisms (i.e., Campylobacter sp.) as the confirmed or presumed cause of abortion. These results suggest that measurement of fetal fluid IgG concentration is a useful, supportive diagnostic test in determining the cause of ovine abortion, and should be included as a routine laboratory procedure for ovine abortion diagnosis.     

Comparison of enzyme-linked immunosorbent assay, indirect fluorescent antibody test, and direct agglutination test for detecting Toxoplasma gondii antibodies in naturally aborted ovine fetuses

Results obtained in an enzyme-linked immunosorbent assay (ELISA), an indirect fluorescent antibody test (IFA), and a modified direct agglutination test (MAT) for Toxoplasma gondii antibodies from examination of fetal fluids from 377 aborted ovine fetuses were compared. Sixty-seven samples were positive by MAT (titers 1:16 to greater than 1:65,536), 58 were positive by ELISA, and 62 were positive by immunoglobulin G-IFA. The MAT was preferred because it required less time, labor, and special equipment. It was simple to run, could be done on serum from any species without modification, and it was more effective than the IFA for detecting toxoplasma antibodies in severely autolyzed fetuses. No advantage was found in determining immunoglobulin M antibodies in ovine fetal sera.     

Immunoblot analysis of calpastatin degradation: evidence for cleavage by calpain in postmortem muscle.

A negative correlation exists between calpastatin activity and meat tenderness. Therefore, it is important to determine the mechanism of calpastatin inactivation in postmortem skeletal muscle. Western immunoblot analysis was performed to determine the protease(s) responsible for degradation of muscle calpastatin during postmortem storage. To accomplish this, purified calpastatin was digested with different proteases in vitro, and their pattern of calpastatin degradation was compared with that of calpastatin degradation in postmortem muscle. Polyclonal antibodies raised in mice against recombinant bovine skeletal muscle calpastatin were used to monitor calpastatin degradation. Lamb longissimus was stored at 4 degrees C and sampled at 0, 6, 12, 24, 72, 168, and 336 h postmortem. Postmortem storage produced a discrete pattern of calpastatin degradation products that included immunoreactive bands at approximately 100, 80, 65, 54, 32, and 29 kDa. Undegraded calpastatin (130 kDa) was barely detectable after 72 h of postmortem storage at 4 degrees C, and no immunoreactive calpastatin was observed by 336 h postmortem. For in vitro proteolysis, lamb longissimus calpastatin (0 h postmortem) was purified using Affi-Gel Blue chromatography. Calpastatin was digested with m-calpain, mu-calpain, cathepsin B, proteasome, trypsin, or chymotrypsin. Each of these enzymes degraded calpastatin. Immunoreactive fragments resulting from digestion of calpastatin with m- and mu-calpain were similar to each other and closely resembled those observed during postmortem aging of lamb longissimus at 4 degrees C. Digestion of calpastatin with mu-calpain reduced calpastatin activity. Degradation of calpastatin by other proteases resulted in unique patterns of immunoreactive fragments, distinct from that observed in longissimus. Thus, m- and(or) mu-calpain seem to be responsible for calpastatin degradation during postmortem storage of meat.     

Haemorrhagic disease of lagomorphs: evidence for a calicivirus.

Studies on the aetiological agents of rabbit haemorrhagic disease (RHD) and European brown hare syndrome show that the viruses responsible for these infections can be placed in the family Caliciviridae. Established members of this group are vesicular exanthema virus (prototype), San Miguel sea lion virus and feline calcivirus. The human hepatitis E virus and the Norwalk agent may soon be included. The RHD virus genome consists of a positive stranded RNA molecule composed of 7437 nucleotides. A major subgenomic RNA of 2.2 kb, colinear with the 3' end of the genomic RNA, can also be recovered from infected liver tissue, and both RNAs are enclosed within viral capsids formed by a single major protein of approximately 60 kDa. Electron microscopic examination of organ suspensions from diseased animals shows two types of particle; 35-40 nm complete virions have the regularly arranged cup-shaped depressions typical of calcivirus morphology, and 23-25 nm smooth particles resulting from degradation of the outer surface structures of the complete virions.     

Chlamydophila abortus infection in the mouse: a useful model of the ovine disease

Chlamydophila (C.) abortus is an obligate intracellular bacterium able to colonize the placenta of several species of mammals, which may induce abortion in the last third of pregnancy. The infection affects mainly small ruminants resulting in major economic losses in farming industries worldwide. Furthermore, its zoonotic risk has been reported in pregnant farmers or abattoir workers. Mouse models have been widely used to study both the pathology of the disease and the role of immune cells in controlling infection. Moreover, this animal experimental model has been considered a useful tool to evaluate new vaccine candidates and adjuvants that could prevent abortion and reduce fetal death. Future studies using these models will provide and reveal information about the precise mechanisms in the immune response against C. abortus and will increase the knowledge about poorly understood issues such as chlamydial persistence.     

An outbreak of rickets in Corriedale sheep: evidence for a genetic aetiology

CASE HISTORY: A skeletal disease characterised by lameness, limb deformities and reduced growth rate occurred over two successive years in lambs born on a commercial sheep farm in Marlborough. A genetic aetiology was considered likely following exclusion of other known causes of rickets and because of the progressive nature of the disease, even after affected animals were transferred to another property. CLINICAL FINDINGS: Affected lambs appeared normal at birth but developed clinical signs during the first 2 months of life. The most severely affected animals either died or were euthanised within the first year of life, but some survived to breeding age. Serum biochemistry revealed hypocalcaemia, hypophosphataemia and increased concentrations of 1,25 dihydroxyvitamin D. The mean serum 25 hydroxyvitamin D concentration was similar to that of control lambs. PATHOLOGICAL FINDINGS: Gross lesions included enlarged costochondral junctions, bilateral irregularity of articular surfaces on humeral heads due to collapse of subchondral bone, thickened cortices in long bones and irregular thickening of physeal cartilages. Microscopically, tongues of hypertrophic chondrocytes extended from physes into metaphyseal regions; metaphyseal trabeculae were thick, disorganised and often lined by wide osteoid seams. Osteoclastic activity was excessive both in cortical and trabecular bone. DIAGNOSIS: Inherited rickets in Corriedale sheep. CLINICAL RELEVANCE AND CONCLUSIONS: This disease is likely to be present in several Corriedale sheep flocks in New Zealand and may have been misdiagnosed as arthritis or other diseases causing lameness and/or poor growth. A defect in end-organ responsiveness to 1,25 dihydroxyvitamin D is the likely mechanism. This disease of sheep may be a useful model for studying vitamin D metabolism and the treatment of inherited forms of rickets in human beings.     

Serological study of ovine toxoplasmosis in Colombia: epidemiological study of a field outbreak.

A serological study, using the indirect haemagglutination test, of an outbreak of toxoplasmosis in a flock of blackface sheep is described. The serological aspects of the disease are discussed with reference to this incident, and possible sources of infection are suggested.     

Detection and quantitation of a type D retrovirus gag protein in ovine pulmonary carcinoma (sheep pulmonary adenomatosis) by means of a competition radioimmunoassay

A heterologous competition radioimmunoassay (RIA) which consisted of 125I-labeled langur retrovirus major gag protein and goat anti-squirrel monkey retrovirus serum was used to detect a type D retrovirus-associated antigen in tumor cell homogenates, lung fluid, and cell culture supernatant fluids of naturally occurring and experimentally-induced ovine pulmonary carcinoma (OPC, sheep pulmonary adenomatosis). In this assay, there was no cross reactivity between structural proteins of the type D retrovirus and an ovine lentivirus, which frequently co-infects OPC-affected sheep. The sensitivity of the assay was similar to an immunoblotting assay using antiserum to Mason-Pfizer monkey virus major gag protein which had been used previously to detect the OPC retrovirus antigen in tumor homogenates and lung fluids of OPC-affected sheep. All unconcentrated samples of lung fluid collected from five sheep with naturally occurring OPC or six sheep with experimentally induced OPC competed in the competition RIA. The competition RIA titers of the type D retrovirus antigen in lung fluids of lambs with induced OPC were relatively higher than the titers of this antigen in the naturally occurring OPC cases. The competition RIA detected the retrovirus antigen associated with OPC in the culture fluids of four out of five primary lung cultures from OPC sheep tested between 1 and 56 days after culture initiation. Because this RIA is appropriate for the quantitation of OPC-associated antigen, it will provide a means for determination of the target cell type for OPC virus replication in vitro.     

Retrospective analysis of detomidine infusion for standing chemical restraint in 51 horses

Objective To assess the effectiveness of a detomidine infusion technique to provide standing chemical restraint in the horse. Design Retrospective study. Animals Fifty‐one adult horses aged 9.5 ± 6.9 years (range 1–23 years) and weighing 575 ± 290.3 kg. Methods Records of horses presented to our clinic over a 3‐year period in which a detomidine infusion was used to provide standing chemical restraint were reviewed. Information relating to the types of procedure performed, duration of infusion, drug dosages and adjunct drugs administered was retrieved. Results Detomidine was administered as an initial bolus loading dose (mean ± SD) of 7.5 ± 1.87 µg kg^?1. The initial infusion rate was 0.6 µg kg^?1 minute^?1, and this was halved every 15 minutes. The duration of the infusion ranged from 20 to 135 minutes. Twenty horses received additional detomidine or butorphanol during the procedure. All horses undergoing surgery received local anesthesia or epidural analgesia in addition to the detomidine infusion. A wide variety of procedures were performed in these horses. Conclusions Detomidine administered by infusion provides prolonged periods of chemical restraint in standing horses. Supplemental sedatives or analgesics may be needed in horses undergoing surgery. Clinical relevance An effective method that provides prolonged periods of chemical restraint in standing horses is described. The infusion alone did not provide sufficient analgesia for surgery and a significant proportion of animals required supplemental sedatives and analgesics.