Synovial fluid analysis in cattle: a review of 130 cases

OBJECTIVE: To compare synovial fluid characteristics of cattle with infectious and noninfectious arthritis. STUDY DESIGN: Retrospective cohort study. ANIMAL OR SAMPLE POPULATION: 130 cattle. METHODS: Synovial fluid was analyzed for total nucleated cell count (NCC), absolute number and percentages of polymorphonuclear (PMN) and mononuclear cells, total protein (TP) concentration, and specific gravity. Cattle were categorized as having infectious or noninfectious arthritis based on physical and lameness examinations, joint radiographs, and microbial culture results. Kruskal-Wallis 1-way analysis of variance was used to compare synovial fluid analysis data from different categories. Selection of cut-off values for the calculation of likelihood ratios, sensitivity, specificity, and positive and negative predictive values was based on examination of the distribution of the data using histograms. RESULTS: Cattle with infectious arthritis had significantly higher numbers of total NNC, PMN cells, TP concentration, and specific gravity (P = .0001) and a significantly higher percentage of PMN cells compared with cattle with noninfectious arthritis (P = .0001). The percentage of mononuclear cells was significantly higher in cattle with noninfectious arthritis (P = .0001). CONCLUSIONS: Synovial fluid analysis is useful for differentiation of infectious and noninfectious causes of joint disease in cattle. CLINICAL RELEVANCE: Cattle with a synovial fluid total NCC > 25,000 cells/microL, a PMN cell count > 20,000 cells/microL or more than 80% PMN cells, and TP > 4.5 g/dL should be considered to have infectious arthritis.     

Acanthocephalan infection and sparganosis in a green tree snake (Dendrelaphis punctulata)

Acanthocephalan and spargana parasites were identified within a body wall mass during exploratory surgery in a wild green tree snake. Acanthocephalan parasites have not previously been reported in this species. Surgical excision, the treatment of choice, could not be achieved because of the extensive infiltration of the coelomic cavity.     

Probing the Local Effects of Magnetic Impurities on Superconductivity

The local effects of isolated magnetic adatoms on the electronic properties of the surface of a superconductor were studied with a low-temperature scanning tunneling microscope. Tunneling spectra obtained near magnetic adsorbates reveal the presence of excitations within the superconductor's energy gap that can be detected over a few atomic diameters around the impurity at the surface. These excitations are locally asymmetric with respect to tunneling of electrons and holes. A model calculation based on the Bogoliubov-de Gennes equations can be used to understand the details of the local tunneling spectra.     

Spontaneous formation of macroscopic chiral domains in a fluid smectic phase of achiral molecules

A smectic liquid-crystal phase made from achiral molecules with bent cores was found to have fluid layers that exhibit two spontaneous symmetry-breaking instabilities: polar molecular orientational ordering about the layer normal and molecular tilt. These instabilities combine to form a chiral layer structure with a handedness that depends on the sign of the tilt. The bulk states are either antiferroelectric-racemic, with the layer polar direction and handedness alternating in sign from layer to layer, or antiferroelectric-chiral, which is of uniform layer handedness. Both states exhibit an electric field-induced transition from antiferroelectric to ferroelectric.     

Organic Glasses: A New Class of Photorefractive Materials

The performance of amorphous organic photorefractive (PR) materials in applications such as optical data storage is generally limited by the concentration of active molecules (chromophores) that can be incorporated into the host without forming a crystalline material with poor optical quality. In polymeric PR systems described previously, performance has been limited by the necessity of devoting a large fraction of the material to inert polymer and plasticizing components in order to ensure compositional stability. A new class of organic PR materials composed of multifunctional glass-forming organic chromophores is described that have long-term stability and greatly improved PR properties.     

Nanofabrication of Small Copper Clusters on Gold(111) Electrodes by a Scanning Tunneling Microscope

The use of scanning tunneling microscopy in an electrochemical environment as a tool for the nanoscale modification of gold electrodes was demonstrated. Small copper clusters, typically two to four atomic layers in height, were precisely positioned on a gold(111) electrode by a process in which copper was first deposited onto the tip of the scanning tunneling microscope, which then acted as a reservoir from which copper could be transferred to the surface during an appropriate approach of the tip to the surface. Tip approach and position were controlled externally by a microprocessor unit, allowing the fabrication of various patterns, cluster arrays, and "conducting wires" in a very flexible and convenient manner.     

Risk factors for abomasal volvulus and left abomasal displacement in cattle.

A hospital-based case-control study was conducted to evaluate and compare risk factors for abomasal volvulus (AV) and left displaced abomasum (LDA) in cattle. Medical record abstracts were derived from 17 North American veterinary schools by the Veterinary Medical Data Program for all cattle admitted between Jan 1, 1977 and Dec 31, 1986, and for those with a diagnosis of AV or LDA. From a total of 108,956 individual cattle records, 1,036 cases of AV and 7,695 cases of LDA were identified, with a ratio of LDA to AV cases of 7.4 to 1. In-hospital mortality was 23.5% for AV and 5.6% for LDA. Age, breed, gender, and season each had significant (P less than 0.05) effects on risk for AV and LDA. Risk for AV and LDA increased with increasing age, with greater risk in cattle aged 4 to 7 years. Dairy cattle were at higher risk of developing AV (adjusted odds ratio, 36.4) and LDA (adjusted odds ratio, 95.2) than were beef cattle. The odds of AV in Brown Swiss cattle were significantly (P less than 0.0001) lower, and the odds of LDA in Guernsey cattle were significantly (P less than 0.0001) higher than those in Holstein cattle. Female cattle were also at higher risk of developing AV (adjusted odds ratio, 3.3) and LDA (adjusted odds ratio, 29.1) than were male cattle. The odds of AV and LDA varied considerably throughout the year, with the lowest number of cases observed in autumn. Seasonal development of AV differed significantly (P less than 0.0001) from that of LDA, with the odds of AV and LDA being highest in January and March, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bacterial meningitis and diseases caused by bacterial toxins

Bacterial meningitis most commonly occurs in young calves secondary to septicemia. Clinical signs of hyperirritability are usually seen. Meningitis can be confirmed by cerebrospinal fluid analysis and culture or by necropsy. Intoxications by the exotoxins of Clostridium perfringens types C and D, C. botulinum, and C. tetani are difficult to confirm. The clinical signs of these intoxications vary from flaccid paralysis (botulism) to muscular rigidity (tetanus). Treatment of affected cattle has been unrewarding in botulism and enterotoxemia, whereas early aggressive treatment of tetanus cases can often be successfully resolved. Botulism and enterotoxemia can be proved using mouse inoculation tests, whereas tetanus is diagnosed largely by ruling out other diseases.     

Abomasal volvulus in cattle following correction of left displacement by casting and rolling

Seven adult cows developed abomasal volvulus immediately following correction of left displacement by casting and rolling. Three cows were rolled to provide temporary relief from left displaced abomasum because of concurrent disease and 4 were rolled as the principal therapy for left displacement. In each animal surgical correction of abomasal volvulus was accomplished via right paralumbar fossa celiotomy and inclusion of an omentopexy during abdominal closure. Surgery was performed within 24 hours of casting and rolling. All 7 cows recovered after surgery and were reported to have satisfactory milk production and appetite 6 weeks later.