Hand-assisted laparoscopic left nephrectomy in standing horses

OBJECTIVE: To describe a hand-assisted, laparoscopic technique to remove the left kidney in standing horses. STUDY DESIGN: Prospective evaluation. ANIMALS: Eight horses. METHODS: Food was withheld for a minimum of 12 hours. Horses were sedated with detomidine hydrochloride (0.01-0.02 mg/kg, intravenously) and restrained in standing stocks. The left paralumbar fossa was prepared for surgery, and the surgical site was infiltrated with 2% mepivacaine. Hand-assisted, laparoscopic removal of the left kidney was performed through an incision in the center of the paralumbar fossa; the surgeon's hand was used to isolate the left kidney and associated vasculature. The renal artery and vein were isolated and individually ligated. After vessel transection distal to the ligatures, the left kidney was exteriorized, the ureter ligated and transected, and the incision closed. RESULTS: Laparoscopic removal of the left kidney was successfully performed in all horses. Retroperitoneal infiltration of local anesthesia provided adequate anesthesia. Intraoperative hemorrhage occurred in 3 horses. Surgical duration (initial skin incision to transection of the left kidney) ranged from 20 to 90 minutes. In 2 horses, no signs of pain were noted for 48 hours postoperatively. CONCLUSION: Hand-assisted laparoscopic surgery can be used for removal of the left kidney in horses. Clinical Relevance-Hand-assisted laparoscopic nephrectomy can be safely performed in standing horses; however, care should be taken to identify accessory branches of the renal artery to limit potential complications with hemorrhage.     

Allozyme markers in breeding zone designation

Early studies of allozyme variation in plant populations suggested that allelic frequencies in some loci vary by geography. Since then, the expectation that allozymes might be useful in describing geographic patterns has generally not been borne out by single locus analyses, except on the broadest scale. Multi-locus analyses reveal the converse: canonical correlation analysis of individual, uniformly-spaced genotypes describe statistically-significant, complex patterns with geography. Multi-locus scores in four major species, Abies concolor, Pinus lambertiana, P. ponderosa, and Pseudotsuga menziesii, of the mixed conifer forest in the Sierra Nevada correlate 0.40 or greater with the first canonical vector of a geographical trend surface equation. The different species follow similar patterns by latitude and elevation. In contrast with patterns in the Sierra Nevada, large-scale differentiation is weak (R ² < 0.20) among populations of Pseudotsuga menziesii in the Coast Ranges and Siskyou Mountains of northern California and southern Oregon, where differentiation may be local. For the purpose of forming zones, we subdivided scores of the first two to four canonical vectors into groups and plotted them as multidimensional contour intervals. Reclassification by discriminant analysis serves as an approximate guide to transfer risks within and among these groups.     

Hereditary equine regional dermal asthenia ("hyperelastosis cutis") in 50 horses: clinical, histological, immunohistological and ultrastructural findings

Data on fifty horses with hereditary equine regional dermal asthenia (HERDA; "hyperelastosis cutis") were collected on clinical, histopathological, ultrastructural and immunohistological findings. All horses were Quarter horses or of Quarter horse ancestry. Pedigree evaluation strongly supported an autosomal recessive mode of inheritance. The most common lesions were seromas/haematomas, open wounds, sloughing skin, and loose, easily tented skin that did not return to its initial position. Definitive diagnosis could not be made via histopathology, although the presence of tightly grouped thin and shortened collagen fibres arranged in clusters in the deep dermis was suggestive of the disease. Trichrome, acid orcein-Giemsa and immunohistochemical stains for collagens I and III showed no consistent abnormalities compared to control horses; an increase in elastic fibres was not a consistent finding. Electron microscopy showed no abnormalities in the periodicity of the collagen bundles; neither orientation nor variation of cross-section diameter of the collagen fibrils differentiated control from affected horses. The diagnosis of HERDA relies on clinical presentation, but may be supported by suggestive (although not pathognomonic) histopathological lesions.     

A lag-screw technique for bridging of the medial aspect of the distal tibial physis in horses

A lag-screw technique for transphyseal bridging of the medial aspect of the distal tibial physis in foals with tarsal valgus deformities and results of the technique in 11 foals (6 with bilateral tarsal valgus deformities and 5 with unilateral tarsal valgus deformities) are described. Briefly, horses were anesthetized, and a single stab incision was made through the skin to the underlying bone over the most distal aspect of the medial malleolus. A 20-gauge needle was placed in the incision to guide screw placement, and a lag screw was inserted parallel to the medial cortex of the tibia under radiographic guidance. Screws were removed when the tarsal valgus deformity was clinically assessed to have improved by at least 80%. Clinically, all horses had evidence of a tarsal valgus deformity of > 7 degrees prior to surgery. Mean age at the time of lag-screw implanation was 220 days (range, 116 to 364 days). Mean time the implant was in place was 62 days (range, 39 to 89 days). The tarsal valgus deformity resolved in all 11 horses with excellent cosmetic results.     

Seroprevalence of Mycoplasma alligatoris among free-ranging alligators (Alligator mississippiensis) in Florida--2003.

Mycoplasma alligatoris causes acute lethal infection of alligators (Alligator mississippiensis). The objective of this study was to assess the current seroprevalence of M. alligatoris among free-ranging, juvenile and subadult alligators in Florida. Thirty-two of 592 (5.4%) plasma samples from alligators at 12 of 20 sites (60%) in April and October 2003 were tested seropositive (titer 1: > or = 32) by enzyme-linked immunosorbent assay for anti-M. alligatoris antibodies. These results show that alligators throughout Florida have a recent history of exposure to M. alligatoris and suggest that contact with free-ranging alligators may constitute a risk of lethal infection of susceptible crocodilians.     

In vitro antibiotic susceptibility of Mycoplasma iguanae proposed sp. nov. isolated from vertebral lesions of green iguanas (Iguana iguana).

Mycoplasma iguanae proposed species nova was isolated from vertebral abscesses of two feral iguanas (Iguana iguana) from Florida. Three strains were evaluated for sensitivity to a variety of antibiotics. The minimum inhibitory concentrations for M. iguanae, assessed by broth dilution methods, of clindamycin, doxycycline, enrofloxacin, oxytetracycline, and tylosin (all <1 microg/ml) were lower than those of chloramphenicol (32 micro/ml) and erythromycin (64 microg/ml). The profile was identical to that of Mycoplasma alligatoris, previously isolated from American alligators (Alligator mississippiensis). M. iguanae strain 2327T was subcultured without antibiotics to assess mycoplasmacidal activity. Clindamycin, doxycycline, oxytetracycline, and tylosin were bacteriostatic from 0.1 to 0.5 microg/ml, whereas enrofloxacin was bactericidal at 20 ng/ml. An enrofloxacin dosage of 5-10 mg/kg achieves peak plasma concentrations >1 microg/ml, with an elimination half-life of 6-20 hr, in alligators. Although concentrations achieved in the vertebrae by i.m. or i.v. injection are probably lower than those in plasma, these data suggest that enrofloxacin may be useful to treat M. iguanae mycoplasmosis in iguanas.     

A synthesis of multi-disciplinary research in precision agriculture: site-specific management zones in the semi-arid western Great Plains of the USA

Researchers from Colorado State University, in collaboration with scientists from the United States Department of Agriculture (USDA), initiated a long-term multi-disciplinary study in precision agriculture in 1997. Site-specific management zones (SSMZ) were investigated as a means of improving nitrogen management in irrigated maize cropping systems. The objective was to develop precise nutrient management strategies for semi-arid irrigated cropping systems. This study was conducted in five fields in northeastern Colorado, USA. Two techniques for delineating management zones were developed and compared: SSMZ and yield-based management zones (YBMZ). Nitrogen uptake and grain yield differences among SSMZs were compared as were soil properties. Both management zone techniques were used to divide fields into smaller units that were different with regard to productivity potential (e.g., high zones had high productivity potential while low zones had low productivity potential). Economic analysis was also performed. Based on grain yield productivity, the SSMZs performed better than the YBMZ technique in most cases. Grain yield and N uptake between the low and high productivity management zones were statistically different for most site-years and N fertilizer rates (p < 0.05). Soil properties helped to explain the productivity potential of the management zones. The low SSMZ was markedly different from the high SSMZ based on bulk density, organic carbon, sand, silt, porosity and soil moisture. Net returns ranged from 188 to 679 USD ha^?1. In two out of three site-years the variable yield goal strategy resulted in the largest net returns. In this study, the SSMZ approach delineates areas of different productivity accurately across the agricultural fields. The SSMZs are different with regard to soil properties as well as grain yield and N uptake. Site-specific management zones are an inexpensive and pragmatic approach to precise N management in irrigated maize.