Fatal Pasteurella haemolytica pneumonia in bighorn sheep after direct contact with clinically normal domestic sheep

Six Rocky Mountain bighorn sheep were raised in captivity from birth (n = 5) or taken from the wild as a lamb (n = 1). After the bighorn sheep were in captivity for over a year, 6 clinically normal domestic sheep were placed on the 2 ha of pasture on which the bighorn sheep were kept. Nasal swab specimens were obtained from all sheep at the time the domestic sheep were introduced. Pasteurella haemolytica was isolated from swab specimens obtained from 4 of 6 domestic sheep, but not from specimens obtained from the bighorn sheep. All 6 bighorn sheep died of acute hemorrhagic pneumonia after exposure to domestic sheep. Death in the bighorn sheep occurred on days 4, 27, 27, 29, 36, or 71 after initial exposure to domestic sheep. Pasteurella haemolytica was isolated from respiratory tract tissue specimens of all bighorn sheep at the time of death. None of the domestic sheep were clinically ill during the study. At the end of the study, 3 of 6 domestic sheep were euthanatized, and at necropsy, P haemolytica was isolated from 2 of them. The most common serotypes in bighorn and domestic sheep were P haemolytica T-3 and A-2. Other serotypes isolated included P haemolytica A-1, A-9, and A-11 in bighorn sheep and A-1 in domestic sheep. On the basis of results of this study and of other reports, domestic sheep and bighorn sheep should not be managed in proximity to each other because of the potential fatal consequences in bighorn sheep.     

Lactate dehydrogenase and its isoenzymes in the tissues and sera of clinically normal dogs

The total activity of lactate dehydrogenase (LDH) and the percentage distribution of its isoenzymes in the tissues and sera of clinically normal adult dogs are presented. Total LDH activity was greatest in skeletal muscle followed by heart muscle, kidney, small intestinal mucosa, liver, lung, pancreas and bone. Each tissue had a unique isoenzyme pattern and the proportions of the isoenzymes in serum suggested that liver is the source of normal serum LDH. The tissue isoenzyme patterns were similar to those obtained by other authors in human beings, horses, cattle, sheep and cats although in liver, differences between ruminants and monogastric animals including dogs were evident. The data presented provide a basis for the interpretation of serum LDH isoenzyme patterns in canine disease.     

Activities of ketone body utilising enzymes in tissues of fed and fasted sheep.

The activities of 3-hydroxybutyrate dehydrogenase, 3-ketoacid CoA-transferase and acetyl-CoA acetyltransferase have been measured in the kidney, heart and brain of fed and four-day fasted ewes. The results indicate tha there is a decrease in the capacity of these organs to catabolise ketone bodies in fasting ketosis.     

Isolation of Pasteurella haemolytica and correlation with serum antibody response in clinically normal beef calves

Bacteria from the nasal cavity and trachea were cultured, and serum antibody titers determined for Pasteurella haemolytica serotype 1 in 164 beef calves obtained from a closed herd on range pasture. At the first sampling, P. haemolytica serotype 1 was cultured from 16.4% of the calves. Antibody titers were determined by a quantitative fluorimetric method and the mean titer was 9.5 +/- 5.8. Fifty-seven randomly selected calves were used to study the correlation of serum antibody response and positive culture of P. haemolytica under natural conditions. Clinical signs of respiratory disease were not observed in those calves. During the observation periods, there was a two-fold increase in the percentage of calves that were culture positive. There was no significant difference between mean serum antibody titers or frequency distribution of antibody titers from the two samplings. Comparisons between serum antibody titers, rise in titers, and P. haemolytica isolation failed to reveal any significant correlation. Of the 9 calves that had a decline in antibody titer to P. haemolytica, none was culture positive. Seroconversion to respiratory viruses did not correlate with P. haemolytica related variables.     

Effect of low doses of cosyntropin on serum cortisol concentrations in clinically normal dogs

OBJECTIVE: To determine the lowest of 5 doses of cosyntropin (1.0, 0.5, 0.1, 0.05, or 0.01 microg/kg) administered IV that stimulates maximal cortisol secretion in clinically normal dogs. ANIMALS: 10 clinically normal dogs. PROCEDURES: 5 dose-response experiments were performed in each of the dogs. Each dog received 5 doses of cosyntropin (1.0, 0.5, 0.1, 0.05, and 0.01 microg/kg) IV in random order (2-week interval between each dose). Serum samples for determination of cortisol concentrations were obtained before (baseline) and at 10, 20, 30, 40, 50, 60, 120, and 240 minutes after cosyntropin administration. RESULTS: Compared with baseline values, mean serum cortisol concentration in the study dogs increased significantly after administration of each of the 5 cosyntropin doses. Mean peak serum cortisol concentration was significantly lower after administration of 0.01, 0.05, and 0.1 microg of cosyntropin/kg, compared with findings after administration of 0.5 and 1.0 microg of cosyntropin/kg. After administration of 0.5 and 1.0 microg of cosyntropin/kg, mean peak serum cortisol concentration did not differ significantly; higher doses of cosyntropin resulted in more sustained increases in serum cortisol concentration, and peak response developed after a longer interval. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of cosyntropin IV at a dose of 0.5 microg/kg induced maximal cortisol secretion in healthy dogs. Serum cortisol concentration was reliably increased in all dogs after the administration of each of the 5 doses of cosyntropin. These data should be useful in subsequent studies to evaluate the hypothalamic-pituitary-adrenal axis in healthy and critically ill dogs.     

Properties of myofibril-bound calpain activity in longissimus muscle of callipyge and normal sheep

Properties of the calpain bound to myofibrils in longissimus muscle from callipyge or noncallipyge sheep were examined after 0, 1, 3, and 10 d of postmortem storage at 4 degrees C. Western analysis has shown that most of this calpain is mu-calpain, although the sensitivity of the antibodies used in the earlier studies could not eliminate the possibility that up to 10% of the calpain was m-calpain. The calpain is bound tightly, and very little is removed by washing with the detergent Triton X-100; hence, it is not bound to phospholipids in the myofibril. Over 25% of total mu-calpain was bound to myofibrils from at-death muscle, and this increased to approximately 40% after 1 d postmortem. The amount of myofibril-bound mu-calpain increased only slightly between 1 and 10 d of postmortem storage. The percentage of autolyzed mu-calpain increases with time postmortem until after 10 d postmortem, when all myofibril-bound mu-calpain is autolyzed. The specific activity of the myofibril-bound calpain is very low and is only 6 to 13% as high as the specific activity of extractable mu-calpain from the same muscle. It is unclear whether this low specific activity is the result of unavailability of the active site of the myofibril-bound calpain to exogenous substrate. The myofibril-bound calpain degrades desmin, nebulin, titin, and troponin T in the myofibrils, and also releases undegraded alpha-actinin and undergoes additional autolysis when incubated with Ca2+; all these activities occurred slowly considering the amount of myofibril-bound calpain. Activity of the myofibril-bound calpain was partly (58 to 67%) inhibited by the calpain inhibitors, E-64 and iodoacetate; was more effectively inhibited by a broader-based protease inhibitor, leupeptin (84 to 89%); and was poorly inhibited (43 to 45%) by calpastatin. Release of undegraded alpha-actinin and autolysis are properties specific to the calpains, and it is unclear whether some of the myofibril-bound proteolytic activity originates from proteases other than the calpains or whether the active site of myofibril-bound calpain is shielded from the inhibitors. Activities and properties of the myofibril-bound calpain were identical in longissimus muscle from callipyge and normal sheep, although previous studies had indicated that the "normal" longissimus was much more tender than the callipyge longissimus. Hence, it seems unlikely that the myofibril-bound calpain has a significant role in postmortem tenderization of ovine longissimus.     

Analysis of serum proteins in clinically normal pet and colony cats, using agarose electrophoresis.

The relative and absolute values of the electrophoretic fractions of serum proteins of 50 clinically normal cats were determined, using agarose as the supporting matrix. Six protein fractions were clearly and consistently resolved: albumin and alpha1-, alpha2-, beta1-, beta2-, and gamma-globulins. In many cats, the alpha1-, alpha2-, and beta2-fractions were each divided into 2 subfractions. Cats which lived in a research colony environment were found to have significantly increased levels of gamma-globulins as compared with the values in cats kept as house pets. The results of serum protein fractionation using this technique have been compared with the normal feline values reported in the literature.     

Analysis of serum proteins and cerebrospinal fluid in clinically normal horses, using agarose electrophoresis.

Using agarose as a supporting matrix, electrophoresis was conducted on 50 serum samples and 20 cerebrospinal fluid samples from clinically normal horses (n = 50) of various ages and breeds. The technique was shown to be reliable. A positive correlation between age and gamma-globulin concentration was found in young horses. Features of the electrophoretograms of serum and cerebrospinal fluid samples are discussed, and a nomenclature based on Rf values is proposed.     

Fecal proteolytic activity in clinically normal cats and in a cat with exocrine pancreatic insufficiency

Fecal proteolytic activity determined in single samples collected on each of 3 consecutive days from each of 20 clinically normal cats ranged from 19 to 363 azocasein units (ACU)/g of feces when determined colorimetrically, using azocasein substrate, and ranged from undetectable (in 1 sample from 1 cat) to 21 mm of gel-clearing when determined using radial enzyme diffusion in agar gels containing a casein substrate. Corresponding mean 3-day values for each cat ranged from 29 to 207 ACU/g and from 5 to 16 mm, respectively. Studies of proteolytic activity remaining after treatment of fecal extracts with a specific trypsin inhibitor indicated that trypsin accounted for 0 to 77% of proteolytic activity. In a cat with exocrine pancreatic insufficiency, fecal proteolytic activity was 0, 0, and 3 ACU/g in a sample of feces collected from each of 3 consecutive days and was undetectable by use of radial enzyme diffusion. Assay of fecal proteolytic activity by use of either azocasein hydrolysis or radial enzyme diffusion allows evaluation of pancreatic function in cats, provided that several samples of feces are tested.     

Immunocytochemical study of tissues from clinically normal dogs and of neoplasms, using keratin monoclonal antibodies.

Three commonly used keratin monoclonal antibodies (MAB)--AE1:AE3, CAM 5.2, and MAK-6--were compared with routinely used cytokeratin antibody. The expression of these antibodies was analyzed in several tissues obtained from clinically normal dogs and in a variety of neoplasms from dogs. Using appropriate enzymatic digestion, paraffin-embedded tissues processed in routine manner retained their typical keratin expression. Differentiated and poorly differentiated epithelial neoplasms, lymphomas, and melanomas were studied by use of the avidin-biotin-peroxidase technique. All 4 of the aforementioned antibodies had similar staining profiles. Of 3 anaplastic carcinomas, 2 had positive reaction to all 4 antibodies. All lymphomas, plasma cell tumors, and amelanotic melanomas had negative reaction to MAK-6, CAM 5.2, AE1:AE3, and cytokeratin MAB. Three basal cell epitheliomas had positive reaction to all 4 antibodies, whereas 1 basal cell tumor with a solid pattern had negative staining reaction. Two carcinoids had negative reaction to all markers and 1 of 2 malignant chemodectomas and 1 transitional cell carcinoma had staining reaction to only AE1:AE3 MAB. Comparing the 4 antibodies, use of AE1:AE3 MAB produced the strongest staining intensity followed by cytokeratin, MAK-6, and CAM 5.2 MAB. All 4 antibodies had low background staining. In conclusion, AE1:AE3 and MAK-6 MAB are as useful as cytokeratin MAB for identification of poorly differentiated epithelial neoplasms in dogs and cats.     

青海细毛羊和半细毛羊血清NO和NOS的测定

对生活在海拔 2 2 6 0m的青海细毛羊和海拔 2 5 0 0m的青海半细毛羊血清中NO和NOS进行了测定 ,结果为 :5 0 0 0 μmol/L± 12 71μmol/L和 30 83μmol/L± 2 1 31μmol/L ;2 0 5 0u/mL± 2 4 4u/mL和 19 5 7u/mL± 4 6 5u/mL。青海细毛羊的血清NO含量显著高于半细毛羊 (P <0 0 5 ) ,NOS在两种羊中无显著差异 (P >0 0 5 )。     

Maturational development of drug-metabolizing enzymes in sheep

A qualitative and quantitative assessment was made of the development of hepatic drug-metabolizing enzymes (DME) in sheep as part of a study of the ability of the food-producing species to metabolize drugs. The following DME and components were measured in this study: cytochromes P-450 and b5 and NADPH and NADPH-dependent reductases associated with each of these cytochromes; cytochrome P-450-mediated reactions, including aniline and coumarin hydroxylases, aminopyrine N-demethylase, and 7-ethoxycoumarin 0-deethylase; a uridine diphosphoglucuronic acid glucuronyl transferase with 4-methylumbelliferone as substrate; and glutathione-S-transferase with dinitrochlorobenzene and dichloronitrobenzene as substrates. Amounts or activities of most of these components and enzymes increased up to and beyond the time of weaning. Amount of cytochrome b5 and uridine diphosphoglucuronic acid transferase activity were not affected by age, whereas NADPH cytochrome c (P-450) reductase activity actually decreased after weaning. In some instances (eg, coumarin hydroxylase, cytochrome P-450, and dinitrochlorobenzene-glutathione-S-transferase), differences from preweaning DME values were observed only after sheep were greater than or equal to 6 months old. All other DME activities were definitely increased, compared with the values in lambs before weaning (0 to 12 weeks old). Approximately a third of the sheep studied had some type of clinical disease that might have affected the DME activities. Diseases were classified as sore mouth, pneumonia, foot rot, parasitism, and systemic bacterial infections. Except in a few instances, these diseases had minimal effect on DME activities measured in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)     

Flubendazole metabolism and biotransformation enzymes activities in healthy sheep and sheep with haemonchosis

Bártíková, H., Křížová, V., Lamka, J., Kubíček, V., Skálová, L., Szotáková, B. Flubendazole metabolism and biotransformation enzymes activities in healthy sheep and sheep with haemonchosis. J. vet. Pharmacol. Therap . 33 , 56–62.
The aim of this project was to study the influence of haemonchosis, a common parasitic infection of small ruminants caused by Haemonchus contortus , on the activity of biotransformation enzymes and on in vitro flubendazole (FLU) biotransformation in liver and small intestine of lambs ( Ovis aries ). Twelve lambs were divided into three groups: non-infected animals, animals orally infected with larvae of H. contortus ISE strain for 7 weeks and for 11 weeks. At the end of the experiment, hepatic and intestinal subcellular fractions were prepared and used for assays of biotransformation enzymes activities and FLU metabolism testing. The activities of hepatic cytochromes P450, flavine monooxygenases and carbonyl-reducing enzymes were decreased in infected animals. UDP-glucuronosyl transferase activity was significantly lower (by 35%) in 11 weeks infected animals than that in control animals. When in vitro metabolism of FLU was compared in control and infected animals, significantly lower velocity of FLU reduction was found in infected animals. Slower FLU reduction may be beneficial for the haemonchosis treatment using FLU, because FLU will remain longer in the organism and could cause longer contact of parasites with FLU.     

The calpain system in three muscles of normal and callipyge sheep

Activities of mu- and m-calpain and of calpastatin were measured at four different times during postmortem storage (0, 1, 3, and 10 d) in three muscles from either callipyge or noncallipyge (normal) sheep. The weights of two muscles, the biceps femoris and the longissimus, are greater in the callipyge phenotype, whereas the weight of the infraspinatus is not affected. The activity of m-calpain was greater (P < 0.05) in the biceps femoris and longissimus from callipyge than in those from normal sheep, but it was the same in the infraspinatus in the two phenotypes. The extractable activity of m-calpain did not change (biceps femoris and infraspinatus) or decreased slightly (longissimus) during postmortem storage. Extractable activity of mu-calpain decreased to zero or nearly zero after 10 d postmortem in all muscles from both groups of sheep. The rate of decrease in mu-calpain activity was the same in muscles from the callipyge and normal sheep. At all time points during postmortem storage, calpastatin activity was greater (P < 0.05) in the biceps femoris and longissimus from the callipyge than from the normal sheep, but it was the same in the infraspinatus from callipyge and normal sheep. Calpastatin activity decreased (P < 0.05) in all three muscles from both phenotypes during postmortem storage; the rate of this decrease in the callipyge biceps femoris and longissimus and in the infraspinatus from both the callipyge and normal sheep was slow, especially after the first 24 h postmortem, whereas calpastatin activity in the biceps femoris and longissimus from the normal sheep decreased rapidly. During postmortem storage, the 125-kDa calpastatin polypeptide was degraded, but the 80-kDa subunit of mu-calpain was cleaved only to 76- and 78-kDa polypeptides even though extractable mu-calpain activity declined nearly to zero. Approximately 50 to 60% of total mu-calpain became associated with the nonextractable pellet after 1 d postmortem. The myofibril fragmentation index for the biceps femoris and longissimus from normal sheep increased significantly during postmortem storage. The fragmentation index for the infraspinatus from the callipyge and normal sheep increased to an intermediate extent, whereas the index for the biceps femoris and longissimus from the callipyge did not change during 10-d postmortem storage. The results suggest that postmortem tenderization is related to the rate of calpastatin degradation in postmortem muscle and that calpastatin inhibition of the calpains in postmortem muscle is modulated in some as yet unknown manner.     

Sialic acid and sialyltransferase activity in serum and tissues of dogs with mammary tumors

In humans, the glycosylation pattern of serum and of membrane glycoproteins is associated with invasiveness of tumors: specifically, α2,6-sialylation and α2,3-sialylation are associated with metastasizing and nonmetastasizing tumors, respectively. In turn, the type of sialylation depends on the activity of α2,6 or α2,3 sialyltransferase (ST) enzymes. Because of the high prevalence of metastasizing tumors with biological behavior similar to the human counterpart, female dogs with metastasizing neoplasms could provide a good animal model for investigating the potential roles of sialic acid (Sia) and ST enzymes in the pathogenesis of metastatic tumors. The aims of this study were (1) to validate a solid-phase method based on lectin staining of serum and tissue homogenates to investigate sialylation and ST activity and (2) to compare the results obtained with this method and with lectin staining and to collect preliminary information on sialylation and ST activity in dogs with (n = 8) and without (n = 8) mammary tumors. The data recorded in healthy dogs revealed that serum and tissue glycoproteins are prevalently characterized by a α2,6 sialylation, but ST-α2,3 seems to be the most active enzyme in both samples. Sia-α2,3 and ST-α2,3 activity decreases in serum and tissues of dogs with tumors, especially in a dog with metastasis, suggesting that the equilibrium between ST-α2,6 and ST-α2,3 activity shifts toward the former, as reported in humans.     

Stability and storage characteristics of enzymes in sheep blood

The stability and storage characteristics were studied of 11 ovine enzymes of potential clinical significance, namely, aldolase, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, acetylcholinesterase, creatine kinase, gamma glutamyltransferase, glutathione peroxidase (GSH-Px), alpha-hydroxybutyrate dehydrogenase, lactate dehydrogenase and superoxide dismutase (SOD). Enzyme activities in fresh serum were compared with those in plasma containing various anticoagulants including lithium heparin, EDTA and oxalate/fluoride. The same preservatives were assessed for their effects on the whole blood activities of GSH-Px and SOD. Stabilities of enzymes in plasma and serum stored at room (+20 degrees C), refrigerator (4 degrees C) or deep freeze (-20 degrees C) temperatures were also compared. In addition, SOD and GSH-Px activities in samples stored, at the same temperatures, as whole blood or aqueous lysates were monitored. The results are discussed with particular reference to the differences between sheep and cattle.     

Impedance audiometric measurements in clinically normal dogs

OBJECTIVE: To measure impedance audiometric values in clinically normal dogs that were sedated or anesthetized, evaluate effects of ear flushing on tympanometric measurements, and determine effects of performing acoustic reflex testing in a sound-attenuated room. ANIMALS: 35 mixed-breed and purebred client-owned dogs and 21 laboratory-bred Beagles. PROCEDURES: Tympanometry and acoustic reflex testing were performed on 27 mixed-breed and purebred dogs under isoflurane anesthesia in a non-sound-attenuated room and 21 Beagles under sedation in a sound-attenuated room. Tympanometry was performed on 8 mixed-breed dogs under halothane anesthesia before and after ear canal flushing. RESULTS: Among impedance audiometric values, ear canal volume and compliance peak were smaller in Beagles than in mixed-breed dogs; differences among other values were not detected. Ear canal volume was dependent on body weight. Differences were not found for tympanometric values measured before and after ear canal flushing. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study established reference range values for impedance audiometric measurements in clinically normal dogs under isoflurane anesthesia or sedation. Acoustic reflex testing does not need to be performed in a sound-attenuated room. The ear canals of clinically normal dogs can be flushed prior to performing tympanometry without altering the results. Impedance audiometry may be a useful noninvasive procedure for the diagnosis of otitis media in dogs.     

Effects of testicular biopsy in clinically normal bulls

OBJECTIVE: To determine whether testicular needle biopsy is detrimental to testicular function in clinically normal bulls. DESIGN: Prospective study. ANIMALS: 6 mixed-breed mature bulls. PROCEDURE: A randomly selected testicle from each bull was biopsied with a 14-gauge needle biopsy instrument. Bulls were then evaluated over a 90-day period for changes in scrotal temperature and thermal patterns, ultrasonographic appearance, and quality of spermatozoa. At the end of the 90-day study, bulls were castrated, and testicles were examined grossly and histologically. RESULTS: Changes were detected in scrotal temperatures and thermal patterns and in the breeding soundness examination results during the first 2 weeks of the study. However, there were no long-term changes in semen quality over the course of the experiment. Hyperechoic areas were detected on ultrasonographic examination and corresponded to the areas of penetration by the biopsy instrument. Microscopic lesions that were indicative of testicular dysfunction were not found. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that testicular biopsy is a safe procedure in bulls. Testicular biopsy could possibly be used to further examine bulls that have less than satisfactory results for breeding soundness examinations.