Biomechanical Analysis of the Three-Dimensional Motion Pattern of the Canine Cervical Spine Segment C4–C5

Objective— To study the kinematics of cervical spine segment C₄–C₅ and its association with disc dimensions and the coupled motion (CM) in relation to primary motion (PM).
Study Design— Cadaveric biomechanical study.
Animals— Cadavers of large breed dogs (>20 kg; n=11).
Methods— Spines were freed from muscles. Radiographs were taken orthogonal to the C₄–C₅ disc space and disc thickness, endplate width, and height were measured. Spines were mounted on a simulator for 3-dimensional motion analysis. Data were recorded with an optoelectronic motion analysis system. Range of motion (ROM) and neutral zone (NZ) were determined in the direction of flexion/extension, left/right lateral bending, and left/right axial rotation, as well as the ROM of CM.
Results— ROM in flexion and extension was similar; there was no CM in flexion/extension. Left/right axial rotation and left/right lateral bending were coupled to the same side. CM was 1.72 and 3.56 times the ROM of the PM in lateral bending and axial rotation, respectively. Disc dimensions were positively correlated with body weight. Flexion/extension magnitude was significantly reduced for larger endplates, but axial rotation was not influenced. Lateral bending had no correlation with weight or disc dimensions.
Conclusion— Left/right lateral bending and left/right axial rotation are coupled differently in the C₄–C₅ segment in dogs compared with humans.
Clinical Relevance— The canine C₄–C₅ spinal segment has unique motion coupling patterns that should be considered for dynamic implant designs.     

Clinical Evaluation of Pancarpal Arthrodesis Using a CastLess Plate in 11 Dogs

Objective— To describe the use of a 3.5/2.7 mm CastLess Plate (CLP) for pancarpal arthrodesis (PCA) in dogs.
Study Design— Case series.
Animals— Dogs with traumatic/degenerative carpal disease (n=11).
Methods— Records (September 2006–July 2007) of dogs that had PCA using a 3.5/2.7 mm CLP were reviewed to determine intra- and postoperative complications and use of external coaptation. Follow-up (≥12 months) was obtained by telephone interview of owners.
Results— Thirteen PCA procedures were performed; 5 intraoperative complications occurred in 4 procedures and included iatrogenic metacarpal fissure fracture (2), inability to remove an alignment pin (1), and poor distal plate position (2). External coaptation was used in 4 dogs: concomitant or iatrogenic injuries (3), bilateral PCA (1), for 3–6 weeks. Clinical evaluation 6–24 weeks postoperatively revealed iatrogenic metacarpal fractures to have healed and that 1 postoperative complication (infection) developed. Telephone follow up for 10 dogs (mean, 14 months; range, 12–20 months) revealed no further problems.
Conclusion— PCA using a 3.5/2.7 mm CLP reduces the need for external coaptation and seemingly reduces postoperative morbidity associated with other internal fixation techniques.
Clinical Relevance— PCA can be performed safely and successfully using a 3.5/2.7 mm CLP, with low postoperative morbidity compared with other PCA techniques. Particular attention should be taken when applying the distal component of the plate.     

Isolation of infectious pancreatic necrosis (IPN) virus from non-salmonid fish

Abstract. The isolation and characterization of infectious pancreatic necrosis (IPN) virus from a goldfish, discus fish and bream is described. The fish from which the isolates were recovered showed no pathological signs of IPN. All three virus isolates were neutralized by antiserum to IPN, strain Ab, but not by antiserum to the Sp or VR-299 strains. They were morphologically identical to IPN virus in negative stain electron microscopy, grew in the cytoplasm of BF-2 cells, as shown by immuno-fluorescence and, like IPNV, were stable to heating, lipid solvents and acid pH.     

Virulence of Flavobacterium branchiophilum in experimentally infected salmonids

Abstract. The ability of selected strains of Flavobacterium branchiophilum to attach to and colonize the gills of five species of teleosts (four salmonid and one cyprinid) and cause mortality was investigated. In virulence studies with F. branchiophilum strain LAB4a, cumulative mortality was dose-dependent in rainbow trout, Oncorhynchus mykiss (Walbaum), and ranged from 0 to 75%. However, regardless of dose, the relative amount of gill-associated F. branchiophilum antigen increased 1 h after challenge. The gill-associated F. branchiophilum antigen in fish which survived (moribund fish) increased by four to six times compared to that detected on the gills 1 h after challenge. The gill-associated antigen on moribund fish was not significantly different from that on the gills of dead fish. Flavobacterium branchiophilum strain LAB4a also attached to the gills of brook trout, Salvelinus fontinalis (Mitchell), rainbow trout, chinook salmon, Oncorhynchus tshawytscha (Walbaum), Arctic charr, Salvelinus alpinus (L.), and common shiners, Luxilus cornutus (Mitchell), following a 1-h bath exposure, and caused mortality in all species. The virulence of eight strains of F. branchiophilum for rainbow trout was examined. Both virulent and avirulent strains adhered to the gills following bath exposure (fimbriae were observed on all strains), but only virulent strains had the capacity to further colonize the gills and cause mortality.     

Proliferative kidney disease in rainbow trout Salmo gairdneri Richardson

Abstract. Two entirely separate outbreaks of PKD are described in an attempt to properly define the condition and enable it to be differentiated from other diseases of a similar nature. Losses of up to 75% of fingerling rainbow trout were recorded in one outbreak, illustrating the potentially serious nature of the disease. Although the kidneys showed the most obvious pathological changes, other organs were also affected. The host response was granulomatous in type, the foci of each cellular reaction being 5-20 μm eosinophilic cells considered to be parasitic. The cytoplasm of these cells contained numerous electron dense bodies some with a tail, but each with an electron lucent bar always orientated at right angles to the plasmalemma whenever they were near it. The most obvious cytoplasmic inclusion of these 'parasites' were other cells numbering up to five or six, each with its own nucleus and nucleolus, but devoid of any of the small electron dense bodies. The significance of either of these inclusions is unknown.
A limited differential diagnosis is given, and the argument presented that the condition PKD is the result of infection by a parasite, possibly an amoeba, in combination with poor quality water.     

Behavior disruption in Cebus monkeys as a function of injected substances

Intraperitoneal injections of blood substances from schizophrenic or stressed normal human donors into primates trained to perform a precision timing task resulted in significant prolongation of time taken to complete the task as compared with injections of blood substances from normal donors.