Laparoscopic Adhesiolysis in a Horse

Objective —The purpose of this report was to describe the use of laparoscopy as a method of treatment for abdominal adhesions in the horse.
Clinical Report —Unilateral ovariectomy for removal of a granulosa cell tumor was performed through a diagonal paramedian approach in a 14-year-old Arabian mare. Progressive incisional swelling and hemorrhage culminated in acute incisional dehiscence with herniation of ileum on the sixth postoperative day. Septic peritonitis that responded to parenteral antibiotic therapy was identified 7 days after hernia repair. Seven days later, the mare had signs of abdominal pain, and adhesions of small intestine to the paramedian incision were identified on rectal palpation. Transrectally assisted laparoscopic adhesiolysis was performed. No further complications occurred.
Clinical Relevance —Laparoscopic adhesiolysis may provide better observation of adhesions and reduced postoperative morbidity compared with laparotomy.     

A Comparison of Two Surgical Approaches to the Scapulohumeral Joint in Dogs

Two scapulohumeral arthrotomy techniques were evaluated and compared in 10 normal, young adult greyhounds. A caudolateral approach with craniodorsal retraction of the teres minor muscle (no-tenotomy) and a craniolateral approach with tenotomy of the infraspinatus tendon were each performed unilaterally in 5 dogs. The dogs were evaluated using force plate gait analysis, lameness evaluation, radiography, and goniometry for 5 weeks and then euthanatized. Tenotomy sites and sections of the humeral articular cartilage were collected from shoulder joints that had been operated on and examined microscopically. The same surgical approach was then performed on the contralateral shoulder in the cadavers and exposure of the humeral articular cartilage was measured using planimetry. Peak vertical force applied to the operated limbs in the tenotomy group was significantly less than preoperative levels on day 3 and significantly less than the no-tenotomy group on days 21 and 28. The peak vertical force applied to the operated limbs in the no-tenotomy group was not significantly different from preoperative levels during the study. Scapulohumeral arthrotomy by tenotomy of the infraspinatus resulted in decreased range-of-motion and joint extension compared with joints operated on without tenotomies, but provided significantly greater exposure to the articular surface. Scapulohumeral arthrotomy with craniodorsal retraction of the teres minor muscle did not significantly alter goniometric measurements compared with unoperated joints. Both techniques resulted in similar subjective lameness scores and caused no gross microscopic or radiographic evidence of articular cartilage damage.     

Environmental conditions, satellite imagery, and clupeoid recruitment in the northern Benguela upwelling system

The relationship between oceanographic conditions and clupeoid (pilchard, Sardinops sagax, and anchovy, Engraulis capensis ) recruitment in the northern Benguela upwelling system was investigated from 1981 to 1987 using a time-series of mean weekly SST images. Two approaches were taken. The first involved correlating recruitment success with the number of weekly coastal `SST events' above various cut-off temperatures during the main reproductive season. The second involved constructing a multiple regression model of recruitment success with two independent environmental variables: namely, the number of coastal `SST events' greater than 19°C, and an onshore retention index for the early life-history stages. The retention index was derived from a spatial time-series analysis of the SST images using principal components analysis. In general, pilchard recruitment showed a positive relationship with the `number of SST events' whilst anchovy recruitment had a negative relationship; 1987 was an outlier year, during which there were exceptionally high levels of both pilchard and anchovy recruitment. The multiple regression R ² values were high and significant for both species (pilchard R ² = 0.88, anchovy R ² = 0.96). The regression model also accounted for the 1987 outlier according to levels of onshore retention which, despite low inshore SSTs, were particularly high during the 1986/87 reproductive season. Although these results need to be validated with data from a longer time period, they show how satellite data might be used for predicting clupeoid recruitment success in the northern Benguela.     

Closed Suction Drainage in the Treatment of Infectious Arthritis of the Equine Tarsocrural Joint

Infectious arthritis of the tarsocrural joint was treated in 13 horses with closed suction drainage through a flat, fenestrated, latex (Jackson-Pratt) drain, broad-spectrum antimicrobial agents, nonsteroidal anti-inflammatory drugs, and bandage immobilization. In 11 horses, arthroscopic lavage and debridement were also performed. Ingress drains were placed for lavage in six horses. Ten horses returned to their previous level of competition or were sound. One horse raced but had lameness of the affected tarsocrural joint and dropped in racing class; one horse was euthanatized because of laminitis in the supporting limb; and one horse was lame, but useful as a breeding animal. Closed suction drainage appeared to be a useful treatment in horses with infectious arthritis. Although arthroscopy was not necessary, it facilitated fibrin removal, lavage, and partial synovectomy. Because of the development of Pseudomonas superinfection in one horse, the use of simultaneous ingress catheters was not recommended.     

Cardiovascular Effects of a Continuous Two-Hour Propofol Infusion in Dogs Comparison With Isoflurane Anesthesia

The cardiovascular effects during 2 hours of anesthesia with either a continuous propofol infusion or isoflurane were compared in the same six healthy dogs. Dogs were randomly assigned to be anesthetized with either propofol (5 mg/kg, IV administered over 30 seconds, immediately followed by a propofol infusion beginning at 0.4 mg/kg/min), or isoflurane (2.0% end-tidal concentration). The propofol infusion was adjusted to maintain a light plane of anesthesia. Dogs anesthetized with propofol had higher values for systemic arterial pressure due to higher systemic vascular resistance. Dogs anesthetized with isoflurane had higher values for heart rate and mean pulmonary artery pressure. Cardiac index was not different between the two groups. Apnea and cyanosis were observed during induction of anesthesia with propofol. At the end of anesthesia the mean time to extubation for dogs anesthetized with either propofol or isoflurane was 13.5 min and 12.7 min, respectively. A continuous infusion of propofol (0.44 mg/kg/min) provided a light plane of anesthesia. Ventilatory support during continuous propofol infusion is recommended.     

Effect of plant density on stolon growth and development of contrasting white clover (Trifolium repens) varieties and its influence on the components of seed yield

Plants of two contrasting white clover varieties (cv. Aberystwyth S184 and Olwen) were planted in the field in spring in each of 2 years at four densities (9, 25, 49 and 100 plants m⁻²) in 1-m² plots. The effect of plant density on stolon growth and development and the components of seed yield was subsequently measured.
Stolon growth and development was influenced by plant density, variety and year. At low plant densities both white clover varieties produced longer primary stolons than at higher densities. Plant density, however, had no significant effect on the number of inflorescences at harvest. At the high stolon densities there were significantly fewer reproductive nodes per primary stolon than at the lower plant densities. Plant density did not significantly affect any other seed yield components, but the number of inflorescences at harvest, florets per inflorescence, seed set per floret and 1000-seed weight were all significantly influenced by both variety and year.
The relationship between the vegetative and reproductive growth of white clover is discussed in relation to plant density, variety and climate and the possible role of defoliation managements on inflorescence development.     

COMPUTED TOMOGRAPHIC CHANGES ASSOCIATED WITH THE PREPATENT AND EARLY PATENT PHASE OF DIROFILARIASIS IN AN EXPERIMENTALLY INFECTED DOG

Evolution of pulmonary arterial and parenchymal changes as assessed with computed tomography (CT) is described in a dog experimentally infected with Dirofilaria immitis. The dog was imaged 125, 168, 216, and 402 days after infection. Initial changes during the prepatent phase of infection included enlargement of the peripheral caudal lobar pulmonary arteries and intermittent periarterial interstitial infiltrates. The changes were progressive, involving additional arteries over time, but remained mild. With the presence of adult filariae a filling defect was observed in the caudal lobar pulmonary artery using CT angiography. Recognizing thoracic CT findings associated with the prepatent phase of canine heartworm infection may be important in endemic areas.     

Multiple Osteochondral Autografts for Treatment of a Medial Trochlear Ridge Subchondral Cystic Lesion in the Equine Tarsus

Objective— To adapt the multiple osteochondral autograft technique for treatment of a subchondral cystic lesion (SCL) of the proximal medial trochlear ridge (MTR) of the equine talus and assess long term outcome.
Study Design— Case report.
Animals— Quarter horse stallion with SCL of the proximal MTR of the talus.
Methods— Osteochondral autograft techniques used in dogs and humans were adapted and optimized in equine cadavers. A horse with a SCL of the MTR of the talus was treated by osteochondral autografting. Three osteochondral autografts were harvested from the distal lateral trochlear ridge of the talus in the affected tarsus. No curettage or debridement of the osteochondral lesion was performed. Three recipient beds were predrilled and osteochondral autografts were press-fit into the proximal MTR of the talus. Outcome was assessed by radiography, telephone interview of the owner, and direct observation during training.
Results— Postoperative radiographs indicated excellent filling of the osteochondral defect and graft-articular surface congruency. No complications were encountered after surgery. At 10 months after surgery, the horse successfully re-entered reining training, and continued to be sound and performing athletically 2 years after surgery.
Conclusion— Osteochondral autografting deserves consideration and further evaluation as a primary treatment option for SCL of the proximal MTR of the talus in horses.
Clinical Relevance— Based on the outcome of this case, osteochondral autografting appears to be a safe, valuable and realistic option for treating SCL of the proximal MTR of the talus in equine athletes.     

Laryngeal Hemiplegia in Draft Horses A Review of 27 Cases

Case records of 27 draft horses with laryngeal hemiplegia were reviewed. Twenty-one horses were treated by ventriculectomy with or without prosthetic laryngoplasty, and 17 owners were contacted to determine the results. Fifteen horses improved after surgery and were able to perform to the owners' expectations. Performance improved significantly and hospitalization was shorter after ventriculectomy alone. Results of this study indicate that the clinical signs of exercise intolerance and excessive inspiratory noise associated with left laryngeal hemiplegia in draft horses can be treated successfully by ventriculectomy without prosthetic laryngoplasty.     

Impacts of tillage and application methods on atrazine and alachlor losses from upland fields

The effects of tillage practises and the methods of chemical application on atrazine and alachlor losses through run-off were evaluated for five treatments: conservation (untilled) and surface (US), disk and surface, plow and surface, disk and preplant-incorporated, and plow and preplant-incorporated treatments. A rainfall simulator was used to create 63.5 mm h⁻¹ of rainfall for 60 min and 127 mm h⁻¹ for 15 min. Rainfall simulation occurred 24–36 h after chemical application. There was no significant difference in the run-off volume among the treatments but the untilled treatment significantly reduced erosion loss. The untilled treatments had the highest herbicide concentration and the disk treatments were higher than the plow treatments. The surface treatments showed a higher concentration than the incorporated treatments. The concentration of herbicides in the water decreased with time. Among the experimental sites, the one with sandy loam soil produced the greatest losses, both in terms of the run-off volume and herbicide loss. The US treatments had the highest loss and the herbicide incorporation treatments had smaller losses through run-off as the residue cover was effective in preventing herbicide losses. Incorporation might be a favorable method of herbicide application to reduce the herbicide losses by run-off.