Suspected ciliary dysfunction in Chinese Shar Pei pups with pneumonia

Chronic pneumonia was investigated in a litter of young Chinese Shar Pei in which 4 of 6 dogs were affected. Serum immunoglobulin concentrations (IgA, IgG, IgM) determined by radial immunodiffusion varied over time, but were not consistently lower in affected dogs, compared with control dogs. Two dogs that died had hydrocephalus and lymphoid depletion, in addition to severe broncho-pneumonia. Evaluation of ciliary ultrastructure in 2 affected dogs revealed random orientation of adjacent respiratory tract or oviductal cilia and a greater number of microtubular disarrangements, compared with control dogs. In vivo tracheal mucociliary clearance of 99mtechnetium macroaggregated albumin was absent in 1 dog examined. The ciliary abnormalities were suspected to have resulted in an inefficient mucociliary transport system predisposing to the development of pneumonia. Further evaluation of 1 Chinese Shar Pei revealed lymphocyte mitogenesis results that were not consistently less than those of a control dog, normal total hemolytic complement values, and normal blood neutrophil chemotaxis.     

Evaluation of drug-induced prostatic involution in dogs by transabdominal B-mode ultrasonography

The relative antiandrogen-induced prostate involution activity of the newly synthesized hydroxyflutamide pro-drug was compared with that of flutamide in 25 Beagles. Secondary antiandrogen activity of both drugs on the testes and mammary tissue was investigated. Daily oral administration of both compounds at 2 dosages (ie, 2.5 and 5.0 mg/kg of body weight) during a 7-week period was monitored by transabdominal ultrasonography of the prostate twice a week. Cross-sectional area estimates of the prostate gland calculated from oblique dorsoventral, and transverse sonographic measurements were diminished significantly in some of the treated dogs as early as day 14 of drug administration. All treated dogs had significant differences in reduction by day 47. Involution was related directly to dose (P less than 0.05), but no difference was observed between test compounds. Differences in secondary antiandrogen activity were not remarkable. Flutamide was not found to have any activity advantage in vivo over hydroxyflutamide. It was concluded that ultrasonography can be a highly effective means of monitoring prostate size, and of monitoring drug-induced involution over time.     

Analysis of southern Ontario Actinobacillus (Haemophilus) pleuropneumoniae isolates by restriction endonuclease fingerprinting.

Isolates of Actinobacillus (Haemophilus) pleuropheumoniae were studied by restriction endonuclease fingerprinting (REF) analysis using the enzymes BamHI and HindIII. Restriction fragments were resolved by polyacrylamide gel electrophoresis and visualized by silver staining. Except for serotypes 1 and 9, reference strains of A. pleuropneumoniae serotypes 1 to 10 had clearly distinguishable REF profiles. Analysis of REF profiles of southern Ontario field isolates revealed limited heterogeneity amongst isolates of serotype 1 or serotype 5. The REF profiles of the serotype 7 isolates studied showed greater variation. Heterogeneity could not be correlated with the presence of plasmids nor with antibiotic resistance. Limited heterogeneity could also be detected amongst REF profiles of A. pleuropneumoniae isolates recovered from a closed herd suggesting that there is a small amount of genetic variation within clonal populations.     

Determination of the alteration in fatty acid profiles, sensory characteristics and carcass traits of swine fed elevated levels of monounsaturated fats in the diet

The present study was designed to determine the effects of supplemental fat or oil rich in oleic acid on the fatty acid profiles (FAP) and physical and sensory traits of pork carcasses. Sixty barrows and gilts were equally distributed among five dietary treatments consisting of a control diet of corn and soybean meal and four similar test diets that contained 10% animal fat (45.3 oleic), safflower oil (72.1 oleic), sunflower oil (80.9 oleic) or canola oil (57.7 oleic). The pigs were slaughtered after being fed these diets for 90 d at about 100 kg live weight. Carcass traits, FAP and sensory properties were evaluated for each treatment. First-rib fat thickness, ham muscling score and longissimus muscle areas were not different (P less than .05), but last-rib fat thickness was increased (P less than .05) with the supplemental dietary fat or oils. No differences existed for marbling scores, lean color, firmness or texture scores between the controls and pigs supplemented with either animal fat or safflower oil. However, pigs supplemented with sunflower or canola oil had lower marbling scores, lean color, firmness and texture scores. Fat became softer and more oily (P less than .05) with the supplemental dietary safflower, sunflower and canola oils. Sensory evaluation (loin chops) showed no differences (P less than .05) in sustained juiciness, tenderness or flavor intensity evaluations among treatments. However, the pigs fed canola oil had lower (P less than .05) flavor quality scores or overall palatability evaluations. Chops from the pigs fed canola oil also had 46% more off-flavors than all other treatments.(ABSTRACT TRUNCATED AT 250 WORDS)     

A Comparison of Manual and Power-Assisted Thoracolumbar Disc Fenestration in Dogs

Thoracolumbar disc fenestration was performed in eight canine cadavers. A hole was cut in the anulus fibrosus with a scalpel in four dogs, and with a high speed drill and burr in four dogs. A curette was used to remove as much of the nucleus pulposus as possible. Sixty-five percent of the nucleus pulposus was removed with the power-assisted technique and 41% was removed by manual fenestration. Manual and power-assisted disc fenestration were performed on alternate intervertebral discs from T11-12 to L5-6 in four dogs. Six months after surgery, results of high-detail radiographic and histologic evaluation of the vertebral bodies and discs showed minimal difference in the sequelae of the two techniques. A retrospective medical records analysis and follow-up of 60 clinical cases treated with prophylactic, power-assisted disc fenestration failed to identify any cases with postoperative recurrence of neurologic deficits. Ten percent of the dogs had periodic back pain of unknown etiology, without other signs of intervertebral disc disease. The findings of this study indicate that power-assisted disc fenestration permits more complete evacuation of the nucleus than manual fenestration, causes no more postoperative complications, and results in a low recurrence rate of neurologic deficits.     

Effects of 21-day treatment with melengestrol acetate (MGA) with or without subsequent prostaglandin F2 alpha on synchronization of estrus and fertility in beef cattle

Beef cattle were treated to synchronize estrus using one of three procedures, and effects on subsequent endocrine responses and fertility were studied. Procedures were 1) feeding .5 mg.head-1.d-1 of melengestrol acetate (MGA) for 21 d (M), 2) feeding .5 mg.head-1.d-1 of melengestrol acetate for 21 d followed 14 d later by a single injection of prostaglandin F2 alpha (M + P) and 3) two injections of prostaglandin (PGF) 14 d apart (P). In Exp. 1, 94 beef cows were assigned to be artificially inseminated 12 h after detection of estrus. Procedures for synchronizing estrus did not affect the proportion of cows observed in estrus within 7 d (mean = 70.2%). However, conception rate of cows treated with MGA alone was lower (P less than .01) than that of cows treated with PGF alone (31.8 vs 78.3%). The conception rate of cows in the M + P group was intermediate (57.1%) but greater than that of cows treated with MGA alone (P less than .10). In Exp. 2, 18 heifers were observed for estrus four times daily and bled daily from 1 wk before predicted estrus until second estrus or 35 d post-treatment. Heifers treated with MGA alone maintained lower concentrations of progesterone and higher concentrations of estradiol-17 beta before first estrus than heifers treated with MGA and PGF or PGF alone (P less than .01). Conception rate following insemination was lower after long-term feeding of MGA than after two injections of PGF. Delaying insemination until after a PGF-shortened cycle 14 d after MGA resulted in an intermediate conception rate.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of level of nutrition on the development of resistance to Haemonchus contortus in sheep

Merino wether weaners, 5-months old at the start of the experiment and fed lucerne-based pellets at 600 g per head per day, developed resistance to Haemonchus contortus given as a continuous or "trickle" infection at the rate of 500 larvae 3 times per week over a period of 17 weeks. By contrast, the development of resistance was impaired in weaners fed pellets at 400 g per head per day. Low food intake and protein-energy deprivation, therefore, have a major effect in impairing the development and expression of host-protective immunity against haemonchosis. The point at which low food intake causes outbreaks of haemonchosis in sheep at pasture is critical in determining procedures for prevention and control of the disease.     

Further development of P. multocida vaccines for swine

149 strains with antigen fractions of both A and D type could be found out of 446 P. multocida field strains of porcine origin. Most of them are producing the dermonecrotizing toxin. These A/D strains proved to be virulent in mice and piglets as well. In mice, the vaccination with one of the most virulent and immunogenic A/D strains, inactivated and A1(OH)3 adsorbed caused an immunity against challenge infections with P. multocida of types A, D and A/D. This effect could be confirmed on SPF piglets.     

Experimental transmission of a dermal sarcoma in fingerling walleyes (Stizostedion vitreum vitreum)

Dermal sarcoma is a benign skin tumor of adult walleyes (Stizostedion vitreum vitreum) with a suspected viral etiology. A laboratory study was initiated to determine if the tumor could be experimentally transmitted by inoculating young walleyes with materials prepared from tumors from adult fish. Eighty walleye fingerlings were divided into four groups of 20 fish each. Two groups were inoculated intramuscularly at 4 months of age either with live tumor cells or with cell-free filtrates of sonicated tumor cells. The two other groups were used as controls and were inoculated either with cultured cells from normal walleye fry or with tissue culture media. Neoplasms, similar to the dermal sarcoma affecting adult walleyes, were observed after 4 months only in fingerlings inoculated with cell-free filtrates of sonicated tumor cells. Like the tumor affecting wild adult walleyes, the transmitted tumors were restricted to the dermis and originated from the superficial surface of scales. They never invaded locally and never metastasized. The transmitted tumors differed from tumors of adult walleyes in their severity and the absence of osteoid. The multicentric origin of transmitted walleye dermal sarcoma suggests that the virus spreads systemically and that tumor cells are polyclonal. This successful transmission of the lesion, along with the presence of C-type virus particles budding from tumor cells in two of seven tumor-bearing fingerlings, supports a retroviral etiology.