The Mississippi Sandhill Crane (Grus canadensis pulla), the most endangered North American crane, is considered critically endangered and is protected by Federal and State law. Substantial funding has established the Mississippi Sandhill Crane National Wildlife Refuge in Southern Mississippi and an artificial insemination / breeding facility at the Audubon Center for Research of Endangered Species in New Orleans, Louisiana to promote species recovery. In spite of extensive time, labor, and money invested in captive propagation, juvenile Mississippi Sandhill Cranes suffer substantial mortality due to predation by bobcats (Lynx rufus), coyotes (Canis latrans) and red tailed hawks (Buteo jamaicensis) upon reintroduction to the refuge. Studies have shown decreased avian mortality in reintroduction programs incorporating antipredator conditioning. Appropriate antipredator behaviors are likely innate in cranes, however the object at which to direct these behaviors may require social learning in lieu of the normally long period of parental care known in this species. An antipredator conditioning program was conducted prior to release for 2 years in juvenile Mississippi Sandhill Cranes using live tame predators and conspecific presence to teach predator recognition and appropriate responses. Death of juvenile cranes upon reintroduction to the refuge due to predation has not occurred since the inception of the program. However, factors such as an increase in predator control or differing weather conditions may have contributed to these results. Behavioral results strongly suggest that the presence of adult cranes during antipredator conditioning of subadult cranes is of benefit. With the presence of an adult pair of cranes (models), subadult cranes show significantly more vigilance in the form of the tall alert behavior. Contact call and guard call occurrence were associated with age, however appropriate vocal response to predator presence occurred regardless of whether a model was present. No cranes were harmed during antipredator conditioning procedures, and time and money expenditures were minimal. Antipredator conditioning programs for cranes can be relatively simple and inexpensive with minimal risk to participants. We strongly recommend similar procedures be incorporated into other avian endangered species reintroduction programs.

There is anecdotal documentation that intra-articular administration of liquid silicone is used as a lubricant for equine joints. Effects of silicone polymer on equine articular cartilage and synovial fluid have not been evaluated. The objectives were to characterize the effects of intra-articular administration of liquid silicone polymer on clinical, synovial fluid, and microscopic features in normal middle carpal joints of horses, and to determine if silicone migrates to the axillary lymph nodes. Eight adult horses were used in this study. Two mLs of 1,000 centistoke, medical-grade silicone was injected into one randomly selected middle carpal joint. The opposite middle carpal joint was injected with two mLs of 0.9% NaCl. Degree of effusion, range of motion, pain on flexion, joint circumference, and degree of lameness were determined prior to injection, at 2, 8, 12, 24, 48, and 72 hours after injection, and weekly for 6 weeks after injection. Radiographic examination, synovial fluid analysis, and microscopic examination of synovium, articular cartilage and axillary lymph nodes were performed at the conclusion of the study. Joint circumference for silicone-treated carpi was significantly greater (p < 0.05) than saline-treated carpi from eight to 336 hours after injection. There was a significant association between treated limbs and lameness, lameness after flexion, pain elecited upon maximal flexion of carpus and middle carpal effusion in treated limbs. Radiographic examination did not reveal the presence of osseous abnormalities; however, effusion was present in 4/8 silicone-treated carpi and 2/8 saline-treated carpi. Synovial fluid from silicone-treated and saline-treated carpi had normal protein concentrations and total nucleated cell counts. Synovial fluid from 5/8 silicone-treated carpi had refractile cytoplasmic vacuoles within macrophages. All silicone-treated carpi had synovial hypertrophy with 7/8 silicone-treated carpi demonstrating accumulation of vacuolated cells containing silicone. Examination of articular cartilage from saline-treated and silicone-treated carpi did not reveal a significant difference. Silicone was not definitively demonstrated in any axillary lymph nodes. Administration of silicone into the middle carpal joint resulted in synovitis. A single administration of silicone polymer had no apparent effects on articular cartilage within six weeks of administration.

This study was designed to characterize changes in the content of adenosine triphosphate (ATP) and cellular permeability of gastric and jejunal mucosa during gastric dilatation-volvulus (GDV). Our hypothesis stated that experimental GDV would result in a decrease in ATP content and cellular integrity of the gastric and intestinal mucosa that may improve after decompression and derotation of the stomach. Fifteen medium-to-large mixed-breed male dogs were randomly divided into three groups: GDV dogs, Ischemia dogs and Control dogs. All dogs were maintained on gas anesthesia for 210 minutes. The GDV dogs had a GDV for 120 minutes with a 90-minute period of decompression, gastric derotation and reperfusion equaling 210 minutes. The Ischemia dogs had a GDV maintained for 210 minutes. The Control dogs had no gastric manipulation. Tissue samples were taken in all dogs from the fundus, pylorus and jejunum at 0 (baseline), 120 and 210 minutes. Quantification of mucosal ATP (ìg/ml) was accomplished using high performance liquid chromatography (HPLC). Mucosal cellular permeability was evaluated using Ussing chambers by measuring conductance over 180 minutes (ÄGt). A significant decrease in ATP below baseline occurred in the fundic mucosa in the Ischemia dogs. A significant decrease in ATP was seen in the jejunual mucosa in GDV and Ischemia dogs between baseline and 120 minutes; however, a return to baseline levels was seen in GDV dogs from 120 to 210 minutes. No significant change in Gt from baseline was seen in the fundic mucosa in any dogs. A significant increase in Gt was seen in the jejunal mucosa in the GDV and Ischemia dogs between baseline and 120 minutes. The increase in Gt continued from 120 to 210 minutes and was most profound in the GDV dogs. The decrease in fundic ATP did not coincide with permeability changes. Interestingly, the jejunum showed profound changes in both ATP concentration and permeability. It is the authors opinion that with the decrease in ATP concentration and loss of cellular integrity in the jejunal mucosa, the jejunum could be implicated as a contributor to complications associated with GDV.

These studies were conducted to elucidate the regional analgesic effect that is observed clinically after treatment of orthopedic disorders with application of extracorporeal shock waves in horses. Regional analgesia after treatment with extracorporeal shock waves presents a concern because it may eliminate protective limiting mechanisms and may place equine athletes with predisposing lesions at risk of sustaining career- or life-ending injuries. Direct percutaneous application of non-focused extracorporeal shock waves to palmar digital nerves in the pastern area of horses resulted in decreased sensory nerve conduction velocities compared with untreated control nerves at 3, 7, and 35 days after treatment. Transmission electron microscopy revealed distinct morphological changes consisting of extensive separation and disruption between the different layers of the myelin sheath in large- to medium-sized myelinated axons of treated palmar digital nerves. Treatment of selected areas of the metacarpus in horses with non-focused extracorporeal shock waves failed to identify a regional analgesic effect when cutaneous sensation was assessed by comparing the nociceptive threshold (limb withdrawal reflex latency, LWRL) between treated and non-treated areas after stimulation with a focused light source. The LWRL responses in all horses were comparable in treated and control areas over time with a significant decrease noted at most sites and time points compared with baseline values.

Cranial cruciate ligament (CCL) rupture is a common injury in the dog and major cause of degenerative joint disease. The pathophysiology of CCL rupture in the dog is well described. Osteoarthritis secondary to CCL rupture causes severe pain and lameness. There are many surgical techniques accepted for dogs with CCL rupture. A commonly performed technique is an extracapsular repair with a lateral fabella-tibial suture (LFS) using large diameter nylon leader line (NLL). Mechanical demands placed upon the LFS are high requiring the material used be able to withstand a high amount of force, undergo minimal elongation, and have a high stiffness. Studies evaluating materials for use for LFS have found NLL to have the most appropriate mechanical profile for use. However, the large diameter, low coefficient of friction, and memory of NLL make knot security a concern, as well, the surgical handling of the material is not ideal. Our hypothesis stated that the Securos Cranial Cruciate Ligament Repair System, a commercially available crimp-clamp system used to secure two ends of NLL together for a LFS, would perform mechanically superior to a clamped square knot using NLL. Furthermore, fluorocarbon (polyvinylidene fluoride; PVDF) a novel biomaterial of reduced diameter for a given tensile strength, would mechanically perform better than NLL using a clamped square knot. The Securos Cranial Cruciate Ligament Repair System is an acceptable method of fixation of NLL loops used for LFS. Loops formed with 27 and 36 kgt NLL using the 36 kg Securos® crimp-clamps performed as well or better than a clamped square knot. However, loops secured with the 18 kg Securos® crimp-clamp system using 18 kgt NLL did not perform as well as a clamped square knot, and their use cannot be recommended based on these results. Fluorocarbon leader line (FCL) performed mechanically similar to NLL and eliminated elongation under low load observed with NLL. Steam sterilization has dramatic effects on FCL and is not recommended. Ethylene oxide sterilization showed no significant mechanical or structural changes to FCL and is recommended. Fluorocarbon leader line appears to be an acceptable alternative to NLL for use as a LFS.

The purpose of this study was to investigate methods to induce earlier onset of cyclicity in transitional mares. Two experiments were conducted evaluating the effect of follicular aspiration to advance the onset of cyclicity, more succinctly define criteria for selection of mares for follicular aspiration and to compare aspiration to deslorelin treatment for initiating cyclicity in transitional mares. In Experiment 1, anestrous mares were assigned to control (n=6) or follicular aspiration (n=11). The control mares were monitored twice weekly, until ovulation was detected. The aspiration mares were similarly monitored until a follicle >35 mm was identified, then transvaginal ultrasound guided follicular aspiration was performed. After aspiration, the mares were monitored for luteal tissue formation. In Experiment 2, anestrous mares were assigned to control (n=14), follicular aspiration (n=10), or deslorelin (n=12). The control mares were treated as in Experiment 1. The aspiration mares were monitored in the same manner as Experiment 1 but were treated only if uterine edema was present. The deslorelin treated mares were monitored similarly to the aspiration mares, but instead of aspiration the mares were administered deslorelin. In both experiments, plasma was obtained at each examination from all mares to verify a rise in progesterone. In Experiment 1, the time from January 1 to the first rise in serum progesterone was 23.8 days earlier for aspiration treated mares than for control mares (80.5±7.3 and 104.3±8.8 days, mean±SE, for aspiration and control groups, respectively; P=0.024). In Experiment 2, there was no significant difference in time from January 1 to the first rise in serum progesterone between groups (100.4±5.8, 113.0±3.0 and 110±6.7 days, for the aspiration, control and deslorelin groups, respectively, P=0.328). However, if mares that did not receive a repeat aspiration treatment due to lack of uterine edema are excluded, there was a significant difference between the aspiration and control groups (93.9±6.7 and 113.0±3.0 days, for the aspiration and control groups, respectively, P=0.045). Results of this study indicate that follicular aspiration of a follicle > 35 mm during late transition may be a means to advance the onset of cyclicity in mares.

Hysteroscopic insemination in mares with delayed uterine clearance (DUC mares) is controversial. While some authors proposed that insemination with a reduced volume and number of spermatozoa may reduce post-mating endometritis, others proposed that the hysteroscopic procedure is inflammatory and should not be used in DUC mares. The overall objectives of this study were to evaluate the incidence and severity of post-mating endometritis in reproductively normal and DUC mares after hysteroscopic insemination at the uterotubal junction, and to determine if hysteroscopic insemination could be used in DUC mares to reduce post-mating endometritis. The mares were classified as normal or DUC based on the presence of intrauterine fluid 24 or 48 hours after a semen challenge. In Experiment 1, the acute endometritis was evaluated 24 hours after insemination. Each mare (n=5 normal, n=5 DUC) received three treatments in three consecutive estrous cycles: UB: uterine body insemination (one billion spermatozoa, 20 mL), HYST: hysteroscopic insemination (five million spermatozoa, 0.5 mL) and SHAM: sham hysteroscopic insemination (semen extender, 0.5 mL). Intrauterine fluid accumulation and uterine leukocyte numbers were not influenced by treatment. In the second experiment, residual endometritis was assessed 48 hours after insemination, and the effect of insemination method on fertility was evaluated. Each mare (n=4 normal, n=5 DUC) received four treatments in four consecutive estrous cycles: UB: uterine body insemination (one billion spermatozoa, 20 mL), HYST: hysteroscopic insemination (five million spermatozoa, 0.5 mL), SHAM: sham hysteroscopic insemination (semen extender, 0.5 mL) and SP: hysteroscopic infusion of seminal plasma (0.5 mL). There was no difference in intrauterine fluid accumulation between treatments in normal mares. HYST and SHAM treatments resulted in more fluid accumulation 24 hours after the procedures in DUC mares than UB and SP. However, leukocyte numbers were not different. It was concluded that the hysteroscopic procedure itself is inflammatory, so it should not be used with the intention of reducing post-mating endometritis. However, the inflammation was not greater than that induced by routine uterine body insemination and fertility was not affected. Therefore, there is no contraindication to its use in mares with delayed uterine clearance.

The murine pathogen Helicobacter hepaticus has important confounding effects on research. Neonatal fostering has been studied in our laboratory for elimination of infection in mice. The purpose of our study was to examine fostering of pups from experimentally infected dams in male-absent parturition, and to determine the significance of gender and time on quantity of bacterial colonization in the cecum and feces of C57BL/6 mice. Approximately 20 C57BL/6 mice were fostered per day from one to four days of age. None of the C57BL/6 pups tested positive by PCR in fecal or cecal samples through four days of age. This data showed that removal of the male C57BL/6 mouse prior to parturition is crucial for extending the fostering period to obtain Helicobacter-free mice. In a second experiment, H. hepaticus infected mice were housed under varying arrangements to determine the effects of gender and housing on fecal and cecal colonization. Neither time or housing group affected bacterial fecal shedding. However, there was a significant overall effect of gender and a significant difference between male and female mice in both fecal and cecal bacterial copy number. Male fecal and cecal samples contained more copies of H. hepaticus than did female samples. Additionally, significant correlations between fecal and cecal H. hepaticus values were found both overall and by gender. Novel predictive algorithms were formulated to predict cecal bacterial colonization levels in fecal pellets. These findings should prove useful in Helicobacter elimination efforts, and in future work to further elucidate the role of H. hepaticus in transmission and disease.

Intraoperative reductions in serum fentanyl levels in dogs with induced moderate hypothermia and transdermal fentanyl patches (TDF) in place has been documented. The impact of such reductions has not been evaluated nor has the anesthetic sparing effect of the TDF. Reductions in serum levels may be the result of either a decreased uptake of fentanyl from the dermal depot, or a biophase shift. The objective of this investigation was to determine whether the minimum alveolar concentration (MAC) of isoflurane was altered in the presence of TDF in normothermic and hypothermic dogs. Six mature, healthy, mixed breed dogs were anesthetized on four separate occasions, and received each of the 4 following treatments in random order: 1. Sham patch-normothermia (C-NORM), 2. Sham patch-hypothermia (C-HYPO), 3. Fentanyl patch-normothermia (F-NORM), 4. Fentanyl hypothermia (F-HYPO). The appropriate patch was applied twenty four hours prior to induction of anesthesia. Anesthesia was induced with isoflurane in oxygen; the dogs were intubated and mechanical ventilation was initiated. Target temperatures (34.5ºC- HYPO, or within 1ºC of baseline- NORM) were held constant for one hour prior to beginning the MAC determinations. Supramaximal stimulation was produced by an electrical stimulator which delivered a current to needle electrodes in the buccal mucosa of the lower jaw of the dog. The MAC (± SD) for C-NORM, C-HYPO, F-NORM and F-HYPO was 1.2 ± 0.17, 0.855 ± 0.183, 0.763 ± 0.097, and 0.830 ± 0.172 respectively. MAC for C-NORM was significantly higher than the other groups. There was no significant difference between C-HYPO, F-NORM, and F-HYPO. Transdermal fentanyl reduces the isoflurane requirement in normothermic dogs. The presence of hypothermia appears to negate the effects of TDF.

Gopher tortoise (Gopherus polyphemus) populations have experienced precipitous declines from habitat loss, and human and disease related mortality. The goal of this study was to characterize the health status of free-ranging Louisiana gopher tortoises. Gopher tortoises were collected during two distinct trapping seasons: fall (August-October 2002) and spring (April-June 2003). Captured tortoises were given a physical exam and the carapace and plastron length and width, weight, and body temperature were recorded. Blood was collected from the subcarapacial vein and submitted for the following testing procedures: complete blood count, plasma chemistry, infectious disease serology (Mycoplasma), and toxicologic screen (copper, mercury, zinc, and lead). Fifty-nine tortoises were captured during the study. Fifty-seven (97%) of the tortoises were adult animals and two (3%) were juveniles. Twenty (34%) of the tortoises were captured in the fall and thirty nine (66%) were captured in the spring. There were thirty male (53%) and twenty-seven female (47%) tortoises captured between the two trapping periods. The gender of the hatchling tortoises could not be determined. Complete blood counts, plasma biochemistry analyses and toxin screens were performed on fifty seven adult tortoises. There were several differences detected in the white blood cell count between trapping season. The white blood cell count and heterophil count were significantly higher in the spring compared to the fall. Significant gender differences were observed for potassium, calcium, and phosphorus. Marked seasonal variation was observed with glucose, uric acid, and GGT. Only creatinine kinase levels differed significantly between sites. There was a difference in the mercury and copper levels between gender. Only copper differed significantly between season. Overall, 26% of the tortoises were serologically suspect or positive for Mycoplasma agassizii. There was no difference in parasite shedding between gender, site of capture, or season. The parasites identified in these tortoises were consistent with findings in gopher tortoises throughout their range. In general, our findings suggest that these tortoises are in good health.