Structural requirements for efficient prion protein conversion: cofactors may promote a conversion-competent structure for PrP(C).

To understand why cross-species infection of prion disease often results in inefficient transmission and reduced protein conversion, most research has focused on defining the effect of variations in PrP primary structures, including sequence compatibility of substrate and seed. By contrast, little research has been aimed at investigating structural differences between different variants of PrP(C) and secondary structural requirements for efficient conversion. This is despite a clear role for molecular chaperones in formation of prions in non-mammalian systems, indicating the importance of secondary/tertiary structure during the conversion process.

Effects of age and immune suppression of sheep on fecundity, hatching and larval feeding of different strains of Haemonchus contortus.

The effects of host age and immune suppression on abomasal parasitic infection in sheep were investigated following single experimental oral infections with MHco3 (ISE), MHco4 (WRS) and MHco10 (CAVR) strains of Haemonchus contortus in naïve 5-month-old crossbred lambs (n=1 per group) and 15-month-old Greyface sheep treated with methyl prednisolone acetate (n=2 per group) or without corticosteroid treatment (n=2 per group). Adult female H. contortus in 5-month-old lambs (n=1 per group) shed on average 6.

Epidemiological and postmortem findings in 262 red squirrels (Sciurus vulgaris) in Scotland, 2005 to 2009.

Postmortem and virological examinations for squirrelpox virus (SQPV) were carried out on 262 red squirrels (Sciurus vulgaris) found dead or moribund in Scotland between September 2005 and July 2009, to determine the likely causes of death and highlight factors that might be threats to the red squirrel population. Most of the squirrels were submitted from Dumfries and Galloway, and 71 per cent of them were adults. Road traffic accidents, squirrelpox, trauma or starvation were responsible for death in a large proportion (73 per cent) of the squirrels.

Quantitative evaluation of subchondral bone injury of the plantaro-lateral condyles of the third metatarsal bone in Thoroughbred horses identified using nuclear scintigraphy: 48 cases.

Reasons For Performing Study: Increased radio-isotope uptake (IRU) in the subchondral bone of the plantaro-lateral condyle of the third metatarsus (MTIII) is a commonly reported scintigraphic finding and potential cause of lameness in UK Thoroughbred racehorses in training and has not been fully documented.

Objectives: To characterise lameness attributable to IRU of the subchondral bone of MTIII, compare the scintigraphic findings of these horses with a normal population and evaluate the use of scintigraphy as an indicator of prognosis.

Hypothesis: IRU will be in significantly higher in horses with subchondral bone injury and will be related to prognosis and future racing performance.

Prevalence of Clostridium perfringens in faeces and ileal contents from grass sickness affected horses: comparisons with 3 control populations.

Reasons For Performing Study: While previous studies have demonstrated an association between equine grass sickness (EGS) and the presence of Clostridium botulinum within ileal contents and faeces, no such associations with other intestinal-derived anaerobic bacteria have been extensively investigated.

Hypothesis: The prevalence of C. perfringens in the ileal contents and faeces of EGS horses is greater than control horses; the detection of C.

A differential scanning calorimetry study of the effects and interactions of antimicrobial peptide LS3 on phosphatidylethanolamine bilayers.

Differential Scanning Calorimetry studies of a synthetic peptide revealed the peptide decreased the temperature of the lamellar-hexagonal phase transition of cis-trans mixtures of phosphatidylethanolamine. The transition enthalpy varied significantly with lipid composition. The findings are discussed with reference to peptide saturation on the bilayer surface, bilayer thinning and peptide orientation.

Histological and histochemical characterisation of the equine soft palate muscles.

Reasons For Performing Study: Dysfunction of the muscles is implicated in the pathogenesis of intermittent dorsal displacement of the soft palate (DDSP) in exercising horses. The histological features of normal equine soft palate muscles have not been previously described.

Objective: To describe the histological and morphometric features of normal equine soft palate muscles.

A comparison of four systems for scoring recovery quality after general anaesthesia in horses.

Reason For Performing Study: The recovery quality scoring systems (RQSSs) in current use have not been critically reviewed for reliability.

Objective: To examine reliability (reproducibility) of 4 RQSSs when applied to a ranked series.

Methods: A DVD incorporating the recordings of 9 horses recovering from general anaesthesia was evaluated by final year students over 5 days.

Calcium and phosphorus values and their derivatives in captive tortoises (Testudo species).

Objective: To evaluate the relationships between total calcium and phosphorus and ionised calcium and phosphorus values in clinically healthy tortoises.

Methods: Jugular blood samples were obtained from 25 tortoises, as part of a health screen of the population. These comprised Hermann's tortoises, Testudo hermanni boettgeri, spur-thighed tortoises, Testudo graeca ibera, marginated tortoises, Testudo marginata, and horsfield tortoises, Testudo horsfieldi.

Evaluation of platelet activation in canine immune-mediated haemolytic anaemia.

Objectives: To establish whether heightened platelet activation is a common feature of canine immune-mediated haemolytic anaemia, and to evaluate the hypothesis that platelet activation plays a role in the pathogenesis of thromboembolism.

Methods: Using whole-blood flow-cytometric analysis, the proportion of activated platelets and platelet-leucocyte aggregates in blood samples from 14 dogs with immune-mediated haemolytic anaemia and 14 healthy dogs was calculated. General linear models with binomial errors were used to compare groups.

Expression of urocortin peptides in canine myocardium and plasma.

Urocortin (Ucn) peptides are the endogenous ligands for the corticotropin-releasing factor type 2 receptor (CRFR2). They have potentially important roles in cardiovascular physiology in health and disease, and show promise as therapeutics for congestive heart failure. Analysis of canine heart tissue showed mRNA expression of Ucn 1, Ucn 3 and CRFR2 in all heart chambers.

Characterisation of milbemycin-, avermectin-, imidazothiazole- and benzimidazole-resistant Teladorsagia circumcincta from a sheep flock.

Selection for milbemycin resistance in a population of Teladorsagia circumcincta was examined in a sheep flock in which a lack of persistence of an oral dose of 0.2 mg/kg moxidectin against T circumcincta had previously been identified. A faecal egg count reduction test also showed resistance to benzimidazole, levamisole and avermectin anthelmintic groups.

Idiopathic generalized sebaceous gland hyperplasia of the Border terrier: a morphometric study.

Skin biopsies from five Border terriers with histologically confirmed idiopathic, generalized sebaceous gland hyperplasia (Group A) were compared morphometrically to those from four unaffected Border terriers (Group B) and the unaffected dogs to biopsies from four other terrier breeds (Group C). Dogs in Group A had significantly higher numbers of sebaceous gland lobules per hair follicle than those in Group B (P=0.020) but there was no significant difference between Groups B and C.

Cutaneous Alternaria infectoria infection in a dog in association with therapeutic immunosuppression for the management of immune-mediated haemolytic anaemia.

A 4-year-old, ovariohysterectomized, English springer spaniel on immunosuppressive therapy was re-examined for the review of its immune-mediated haemolytic anaemia and the recent development of skin lesions. For the 3 months since hospital discharge, the dog had been receiving 1.3 mg/kg prednisolone and 2.

Osteomyelitis and osteonecrosis after intraosseous perfusion with gentamicin.

Objective: To describe and discuss previously unreported complications associated with intraosseous perfusion with gentamicin in horses.

Study Design: Case report.

Animals: Ten-year-old Warmblood gelding.

Evaluation of formalin-fixed ileum as the optimum method to diagnose equine dysautonomia (grass sickness) in simulated intestinal biopsies.

Equine dysautonomia, or grass sickness, is a frequently fatal disease of unknown etiology, manifested as poor gastrointestinal motility and colic as a result of degenerative changes in the autonomic nervous system. Examination of ileal biopsies collected at laparotomy is currently the best antemortem diagnostic method to distinguish equine dysautonomia from colic cases, which can present with similar signs, but their value has not been previously critically evaluated. Using simulated biopsies collected postmortem from 23 cases of equine dysautonomia and 11 of colic, the sensitivity and specificity of 1-cm long, formalin-fixed ileal biopsies was 100% for the diagnosis of equine dysautonomia.

Morphological study of tracheal shape in donkeys with and without tracheal obstruction.

Reason For Performing Study: There is limited information on the gross tracheal morphology of donkeys with or without tracheal abnormalities.

Objectives: To: 1) examine the morphology of tracheas of donkeys with and without clinical and/or post mortem evidence of tracheal obstruction; 2) record the cross-sectional dimensions and shapes of tracheal rings at fixed sites; and 3) document prevalence, sites and characteristics of detected tracheal abnormalities.

Methods: The tracheas of 75, predominantly aged (median age 30 years, range 7-48 years) donkeys that died or were subjected to euthanasia on humane grounds were examined.

A study of the thickness of cheek teeth subocclusal secondary dentine in horses of different ages.

Reasons For Performing Study: There is limited knowledge on the thickness of subocclusal secondary dentine in equine cheek teeth (CT).

Hypotheses: Subocclusal secondary dentine is of consistent thickness above different pulp horns in individual horses and its thickness increases with age.

Methods: 408 permanent CT were extracted post mortem from 17 horses aged 4-30 years, with no history of dental disease.

Assessment of the incidence of GDV following splenectomy in dogs.

Objective: To establish if splenectomy increases the incidence of gastric dilatation and volvulus (GDV) in dogs.

Methods: Two case-series studies of cases and controls were performed. Records of dogs that had undergone splenectomy (37 cases) were compared with records of dogs that had undergone other abdominal surgery (43 cases).

Proteomic identification of interactions between histones and plasma proteins: implications for cytoprotection.

Extracellular histones released from cells during acute inflammation contribute to organ failure and death in a mouse model of sepsis, and histones are known to exert in vitro cytotoxicity in the absence of serum. Since addition of histones to serum and plasma is known to induce protein aggregation, we reasoned that plasma proteins may afford protection from cytotoxicity. We found that MODE-K mouse small intestinal epithelial cells were protected from histone-induced toxicity in the presence of 10% FCS.

Anatomical studies of maxillary cheek teeth infundibula in clinically normal horses.

Reasons For Performing Study: Although clinical disorders of equine maxillary cheek teeth (CT) infundibula are common, anatomical knowledge of these structures is poor.

Hypothesis: Anatomical examinations of sectioned CT infundibula will better define their shapes and sizes and allow identification of infundibular cemental variations and changes.

Material And Methods: Cheek teeth were extracted post mortem from 33 horses, aged 3-30 years, without a clinical history of dental disease.

Low density subcellular fractions enhance disease-specific prion protein misfolding.

The production of prion particles in vitro by amplification with or without exogenous seed typically results in infectivity titers less than those associated with PrP(Sc) isolated ex vivo and highlights the potential role of co-factors that can catalyze disease-specific prion protein misfolding in vivo. We used a cell-free conversion assay previously shown to replicate many aspects of transmissible spongiform encephalopathy disease to investigate the cellular location of disease-specific co-factors using fractions derived from gradient centrifugation of a scrapie-susceptible cell line. Fractions from the low density region of the gradient doubled the efficiency of conversion of recombinant PrP.

Effect of 'tongue tie' use on racing performance of thoroughbreds in the United Kingdom.

Reasons For Performing Study: There is contradictory published evidence on the potential efficacy of 'tongue ties' (TTs) for treatment of intermittent dorsal displacement of the soft palate (DDSP) in racehorses.

Objectives: To evaluate the effect of TTs on racing performance in Thoroughbred racehorses in the U.K.

Inverse correlation of thermal lability and conversion efficiency for five prion protein polymorphic variants.

Transmissible spongiform encephalopathies (TSEs) are associated with the accumulation of deposits of an abnormal form, PrP(Sc), of the host-encoded prion protein, PrP(C). Amino acid substitutions in PrP(C) have long been known to affect TSE disease outcome. In extreme cases in humans, various mutations appear to cause disease.