Ex vivo investigation of the use of hydrothermal energy to induce chondrocyte necrosis in articular cartilage of the metacarpophalangeal and metatarsophalangeal joints of horses

OBJECTIVE: To evaluate the use of hydrothermal ablation of articular cartilage for arthrodesis in horses through investigation of the effects of joint lavage with physiologic saline (0.9% NaCI) solution (80 degrees C) for various treatment times on chondrocyte viability in the articular cartilage of the metacarpophalangeal and metatarsophalangeal joints of cadaveric horse limbs. Sample Population-7 pairs of metacarpophalangeal and 8 pairs of metatarsophalangeal joints from 8 Thoroughbreds. PROCEDURE: The horses were euthanatized for reasons unrelated to musculoskeletal disease. On a random basis, 1 joint of each pair underwent intra-articular lavage for 5, 10, or 15 minutes with heated saline solution (80 degrees C); the other joint underwent sham treatment of similar duration with saline solution at 22 degrees C (control). Cartilage samples from the distal articular surface of metacarpus III (or metatarsus III), the proximal surface of the proximal phalanx, and the lateral and medial proximal sesamoid bones were assessed for chondrocyte viability via confocal microscopy and viability staining following enzymatic digestion. RESULTS: Compared with the control joints, findings of both viability assays indicated that the percentage of sites containing viable chondrocytes in heat-treated joints was decreased.Treatment hazard ratios of 0.048 (confocal microscopy) and 0.2 (digestion assay) were estimated. Histologically, periarticular soft tissues had minimal detrimental effects after heat treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Ex vivo intra-articular lavage with saline solution at 80 degrees C resulted in the death of almost all articular chondrocytes in the joint. This technique may be a satisfactory method for extensive cartilage ablation when performing arthrodesis by minimally invasive techniques.     

Auscultation and echocardiographic findings in Bull Terriers with and without polycystic kidney disease

OBJECTIVE: To investigate a possible association between Bull Terrier polycystic kidney disease (BTPKD) and cardiac disease, to determine the prevalence of mitral valve disease (MVD) and left ventricular outflow tract obstruction (LVOTO) in the Australian Bull Terrier population, and to compare auscultation and echocardiography in detection of cardiac disease in Bull Terriers. DESIGN: Ninety-nine Bull Terriers, ranging in age from 8 weeks to 13 years and 11 months were auscultated and examined using renal ultrasonography; 86 were also examined using echocardiography. The prevalence and severity of heart defects in dogs with BTPKD was compared with that in dogs without BTPKD. RESULTS: Nineteen of these 99 dogs were diagnosed with BTPKD. Forty-two percent of Bull Terriers with BTPKD and 28% of those without BTPKD had murmurs characteristic of mitral regurgitation or LVOTO. How recently an animal was descended from an ancestor with BTPKD was associated with presence (P = 0.008) and loudness of a murmur (P = 0.009). Overall, echocardiography detected MVD in 39% of Bull Terriers, with increased prevalence in older animals (P = 0.003). Mitral stenosis was found in eight cases. Fifty-three percent of dogs in this study had evidence of LVOTO, with obstruction consisting of a complex of lesions including dynamic or fixed subvalvular LVOTO, significantly narrowed left ventricular outflow tract or valvular aortic stenosis. Dogs with BTPKD, or those descended from dogs with BTPKD, were more likely to have MVD (P = 0.006), and while LVOTO was not more common in these dogs, if they did have LVOTO, they were more likely to have severe obstruction than dogs with no ancestors with BTPKD (analysed in three ways P = 0.028 to 0.001). In this study, 46% of Bull Terriers without a murmur or arrhythmia had cardiac disease detected on echocardiographic examination. CONCLUSION: Cardiac disease, especially MVD and LVOTO, was common in Bull Terriers in this study, and those with BTPKD had an increased risk of cardiac abnormalities. Auscultation did not detect a significant number of Bull Terriers with cardiac disease.     

Effects of Acid LAC and Kem-Gest acid blends on growth performance and microbial shedding in weanling pigs

Weanling pigs with mean initial BW of 6.04 kg (Exp.1) and 5.65 kg (Exp. 2) and mean age at weaning of 18.2 d (Exp. 1) and 17.7 d (Exp. 2) were used in two 5-wk experiments (Exp. 1, n = 180; Exp. 2, n = 300) to evaluate the effects of an organic acid blend (Acid LAC, Kemin Americas Inc., Des Moines, IA) and an inorganic/organic acid blend (Kem-Gest, Kemin Americas Inc.) on weanling pig growth performance and microbial shedding. In Exp. 1, the 5 dietary treatments were 1) negative control, 2) diet 1 + 55 ppm carbadox, 3) diet 1 + 0.4% Acid LAC, 4) diet 1 + 0.2% Kem-Gest, 5) diet 1 + 0.4% Acid LAC and 0.2% Kem-Gest. In Exp. 2, the 6 dietary treatments were diets 1 through 4 corresponding to Exp. 1, plus 5) sequence 1: 0.4% Acid LAC for 7 d followed by 0.2% Kem-Gest for 28 d, and 6) sequence 2: 0.2% Kem-Gest for 7 d followed by 0.4% Acid LAC for 28 d. Pigs were housed at 6 (Exp. 1) or 10 (Exp. 2) pigs/pen. Treatments were fed throughout the experiment in 3 phases: d 0 to 7, d 7 to 21, and d 21 to 35. In Exp. 1, there were no differences (P > 0.05) in ADG, ADFI, or G:F among the dietary treatments at any time during the study. In Exp. 2, throughout the study, pigs fed carbadox (diet 2) and sequence 1 (diet 5) diets had the greatest ADG (d 0 to 35; 262, 294, 257, 257, 292, and 261 g/d, diets 1 through 6, respectively; P < 0.05), greater ADFI than all other acid treatments (P < 0.05), and tended to have greater ADFI than diet 1 (P < 0.10). Fecal pH, Escherichia coli concentrations, and Salmonella presence were determined at d 6, 20, and 34 for Exp. 1, and on d 32 for Exp. 2. For both experiments, there was no effect of treatment on the presence of fecal Salmonella (P > 0.10) at any sampling time. In Exp. 1, fecal E. coli concentrations for pigs fed the carbadox (P < 0.05) diet were greater than for pigs fed the combination diet with 0.4% Acid LAC and 0.2% Kem-Gest on d 34, and the pigs fed the negative control diet tended (P < 0.10) to have greater fecal E. coli concentrations than those fed the combination diet on d 34. In Exp. 2, fecal pH of pigs fed sequence 1 tended to be greater than fecal pH of pigs fed diet 1, diet 4, or sequence 2 (P < 0.10), but there was no dietary effect on fecal E. coli. In Exp. 1, growth performance of pigs fed the Acid LAC and Kem-Gest diets was similar to each other and to that of the carbadox-fed pigs. Adding the combination of 0.4% Acid LAC and 0.2% Kem-Gest to nursery pig diets reduced ADFI and pig growth rate. In Exp. 2, pigs fed the acid sequence of Acid LAC-Kem-Gest had similar growth performance to pigs fed carbadox, and this novel dietary acid sequence may have merit as a replacement for antibiotics in the nursery phase.     

Heartworm genomics: unprecedented opportunities for fundamental molecular insights and new intervention strategies

Vector-borne diseases, including canine heartworm disease (CHWD), are of major socioeconomic and canine health importance worldwide. Although many studies have provided insights into CHWD, to date there has been limited study of fundamental molecular aspects of Dirofilaria immitis itself, its relationship with the canine host, its vectors, as well as the potential of drug resistance to emerge, using advanced -omic technologies. This article takes a prospective view of the benefits that advanced -omics technologies will have toward understanding D. immitis and CHWD. Tackling key biological questions using these technologies will provide a "systems biology" context and could lead to radically new intervention and management strategies against heartworm.     

Age and the ability of calves to respond to a leptospiral vaccine

The serological responses of calves at two different ages to a commercial hardjo/pomona vaccine were examined. Microscopic agglutination test (MAT) titres of a group of ten three-month-old calves and three groups of 11,12 and 12 six-month-old calves were monitored over a period of 28 weeks. The calves vaccinated at three months of age had a poorer serological response rate to vaccination (30% responded to pomona and 40% responded to hardjo) compared with those vaccinated at six months of age (91-100% responded to pomona and 83-91% responded to hardjo). Those three-month-old calves which did respond also produced a lower level of-antibody than six-month-old calves. It was concluded that in order to achieve adequate protection using commercially available leptospiral bacterins at the recommended dose, vaccination should not be undertaken routinely with animals less than six months of age. Where circumstances arise in which earlier vaccination is necessary, repeat vaccination for continued protection at six months or older is suggested.     

Triple antimicrobial therapy and acid suppression in dogs with chronic vomiting and gastric Helicobacter spp

BACKGROUND: Helicobacter pylori is a common cause of gastritis and peptic ulcers in humans. Many dogs, including those with gastritis and chronic vomiting, are infected with Helicobacter spp. HYPOTHESIS: Triple antimicrobial therapy will eradicate Helicobacter infection, improve gastritis, and reduce clinical signs. The addition of acid suppression medication will not improve results. ANIMALS: Twenty-four pet dogs with chronic vomiting and gastric Helicobacter spp. METHODS: Dogs were randomly assigned to triple antimicrobial therapy with or without famotidine. Gastroduodenoscopy was performed 4 weeks and 6 months after therapy. Helicobacter spp status was determined by histologic assessment of gastric mucosal biopsy specimens. RESULTS: Eradication rates for each treatment were not significantly different and combined were 75 and 42.9% at 4 weeks and 6 months, respectively. A greater improvement in gastritis scores occurred in dogs that became Helicobacter spp negative. Overall, the frequency of vomiting was reduced by 86.4%, but there were no differences between treatments. CONCLUSIONS AND CLINICAL IMPORTANCE: Eradication rates of Helicobacter spp with both treatments were not significantly different. Eradication rates at 6 months were modest, and more effective treatments should be developed. Acid suppression is not a necessary component of treatment protocols for dogs. Eradication of gastric Helicobacter spp was associated with improvement in gastritis scores. Dramatic reduction of the vomiting frequency occurred with both treatment protocols. Gastric Helicobacter spp may cause or contribute to chronic vomiting and gastritis in some dogs.     

Effect of orally administered Lactobacillus casei on porcine reproductive and respiratory syndrome (PRRS) virus vaccination in pigs

The purpose of this study was to determine whether intranasal/oral administration of probiotics can assist vaccination efficacy against an important swine pathogen, porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV). A controlled challenge trial was performed employing: (a) pigs vaccinated against PRRS and treated with a Lactobacillus casei, (b) pigs vaccinated against PRRS only, (c) pigs treated with L. casei only, and (d) pigs neither vaccinated against PRRS nor treated with L. casei. All pigs were challenged intranasally with a wild PRRSV strain. There was no difference in clinical signs or rectal temperature among the four groups. However, pigs that received L. casei gained significantly more weight than pigs that did not. Vaccinated pigs did not gain more weight than nonvaccinated pigs. Vaccinated groups had significantly fewer viraemic pigs on days post-challenge 4, 11 and 17 than nonvaccinated groups of pigs. There was no effect of probiotic on prevalence or duration of viraemia. Among viraemic pigs, there was no significant difference in mean log base(10) titer of PRRS virus among groups. These results suggest that orally administered L. casei does not affect immune response in such a way as to affect PRRS viraemia or nasal shedding. However, it still appears to provide significant benefit when administered during vaccination as indicated by the higher bodyweight gain following PRRS virus infection.     

Genetic relationship, inbreeding and generation interval in registered Gir cattle in Brazil

SUMMARY: Two-hundred random pedigrees of cows and fifty of sires born in 1987 from the Gir herdbook of the Brazilian Association of Zebu Breeders were analized. The bull Chave de Ouro DGR no. 2851 was the most influential animal with a 7% direct relationship to the breed. Total average inbreeding was 3.62 and 3.25 for the female and male sample, respectively. The subdivision of total inbreeding into current and non-current components resulted in values of 1.62, 1.25, 2.00 and 2.00 for the female and male sample, respectively. Long-term inbreeding was the principal component of non-current inbreeding, with values of 1.52% and 1.26%, respectively. Inbreeding due to strain formation strain due formation was less important (0.48% and 0.74%, respectively). The average generation interval was 8.02 years. The breed appears not yet to be subdivided into strains but this process may be starting. The average generation interval for the pedigree population was very high. Culling of old bulls could decrease this interval. ZUSAMMENFASSUNG: Verwandtschaft, Inzucht und Generationsintervall bei Gir Herdbuchrindern in Brasilien 200 zuf?llige Stammb?ume von Kühen und 50 von 1987 geborenen Stieren wurden vom Gir Herdbuch des brasilianischen Zebu Zuchtverbandes genommen. Der Stier Chave de Ouro DGR Nr. 2851 war das einflu?reichste Tier mit einer 7%igen direkten Verwandtschaft zur Rasse. Der gesamte Inzuchtkoeffizient war 3.6 und 3.25% für die weibliche und m?nnliche Stichprobe. Die Unterteilung der gesamten Inzucht in laufende und nicht laufende Komponenten resultierte in Werten von 1.62, 1.25, 2.0, 2.0 für die weibliche und die m?nnliche Stichprobe. Langfristige Inzucht war die Hauptursache für Nicht-Rezente Inzucht mit Werten von 1.5 und 1.26. Inzucht aufgrund von Linienbildung war weniger wichtig (0.48% und 0.74%). Das durchschnittliche Generationsintervall war 8.02 Jahre. Die Rasse scheint noch nicht in Linien unterteilt zu sein, aber dieser Proze? k?nnte begonnen haben. Das durchschnittliche Generationsintervall ist mit 8.02 Jahren sehr hoch. Nichtverwendung alter Stiere k?nnte dieses Intervall verkürzen.     

Effect of surgical technique on limb function after surgery for rupture of the cranial cruciate ligament in dogs

OBJECTIVE: To determine the outcome and effect of surgical technique on limb function after surgery for rupture of the cranial cruciate ligament (RCCL) and injury to the medial meniscus in Labrador Retrievers. STUDY DESIGN: Prospective clinical study. ANIMALS: 131 Labrador Retrievers with unilateral RCCL and injury to the medial meniscus and 17 clinically normal Labrador Retrievers. PROCEDURE: Affected dogs had partial or complete medial meniscectomy and lateral suture stabilization (LSS), intracapsular stabilization (ICS), or tibial plateau leveling osteotomy (TPLO). Limb function was measured before surgery and 2 and 6 months after surgery. Treated dogs were evaluated to determine the probability that they could be differentiated from clinically normal dogs and tested to determine the likelihood that they achieved improvement. RESULTS: No difference was found between LSS or TPLO groups, but dogs treated with ICS had significantly lower ground reaction forces at 2 and 6 months. Compared with clinically normal dogs only, 14.9% of LSS-, 15% of ICS-, and 10.9% of TPLO-treated dogs had normal limb function. Improvement was seen in only 15% of dogs treated via ICS, 34% treated via TPLO, and 40% treated via LSS. CONCLUSIONS AND CLINICAL RELEVANCE: Surgical technique can influence limb function after surgery. Labrador Retrievers treated via LSS, ICS, or TPLO for repair for of RCCL and medial meniscal injury managed with partial or complete meniscectomy infrequently achieve normal function. Results of LSS and TPLO are similar and superior to ICS.     

An adenovirus linked to mortality and disease in long-tailed ducks (Clangula hyemalis) in Alaska

An adenovirus was isolated from intestinal samples of two long-tailed ducks (Clangula hyemalis) collected during a die-off in the Beaufort Sea off the north coast of Alaska in 2000. The virus was not neutralized by reference antiserum against known group I, II, or III avian adenoviruses and may represent a new serotype. The prevalence of the virus was determined in live-trapped long-tailed ducks at the mortality site and at a reference site 100 km away where no mortality was observed. Prevalence of adenovirus antibodies in serum samples at the mortality site was 86% compared to 10% at the reference site. Furthermore, 50% of cloacal swabs collected at the mortality site and only 7% of swabs from the reference site were positive for adenoviruses. In 2001, no mortality was observed at either of the study areas, and virus prevalence in both serum and cloacal samples was low, providing further evidence that the adenovirus was linked to the mortality event in 2000. The virus was used to infect long-tailed ducks under experimental conditions and resulted in lesions previously described for avian adenovirus infections and similar to those observed in long-tailed duck carcasses from the Beaufort Sea. The status of long-tailed ducks has recently become a concern in Alaska due to precipitous declines in breeding populations there since the mid-1970s. Our findings suggest that the newly isolated adenovirus is a disease agent and source of mortality in long-tailed ducks, and thus could be a contributing factor in population declines.