Pharmacokinetics of intraarticular liposomal amphotericin B in goats (Capra aegagrus hircus).

Lameness is a significant welfare concern in goats. Amphotericin B is used via intraarticular (IA) administration in models to study experimentally induced lameness in large animals. The main objective of this study was to estimate plasma pharmacokinetic (PK) parameters for amphotericin B in goats after a single IA administration. Liposomal amphotericin B was administered to ten Kiko-cross goats at a dose of 10 mg total (range: 0.34-0.51 mg/kg) via IA administration into the right hind lateral distal interphalangeal joint. Plasma samples were collected over 96 h. Amphotericin B concentrations were measured via liquid chromatography/mass spectrometry (LC-MS/MS). A non-compartmental analysis was used to derive PK parameters. Following single IA administration, maximum plasma concentration was estimated at 54.6 ± 16.5 ng/mL, and time to maximum concentration ranged from 6 to 12 h. Elimination half-life was estimated at 30.9 ± 16.5 h, and mean residence time was 45.1 ± 10.4 h. The volume of distribution after IA administration was 13.3 ± 9.4 L/kg. The area under the curve was 1481 ± 761 h*ng/mL. The achieved maximum concentration was less than the observed concentrations for other species and routes of administration. Further research is needed into the pharmacodynamics of IA liposomal amphotericin B in goats to determine specific research strategies.

Pharmacokinetics of oral clonazepam in growing commercial pigs (Sus scrofa domestica).

Clonazepam causes sedation and psychomotor impairment in people. Due to similarities between people and swine in response to benzodiazepines, clonazepam may represent a viable option to produce mild-to-moderate tranquillization in pigs. The objective of this study was to determine the pharmacokinetic profile of a single oral dose (0.5 mg/kg) of clonazepam in eight healthy, growing commercial cross pigs. Serial plasma samples were collected at baseline and up to 96 h after administration. Plasma concentrations were quantified using reverse-phase high-performance liquid chromatography, and compartment models were fit to time-concentration data. A one-compartment first-order model best fits the data. Maximum plasma concentration was 99.5 ng/mL, and time to maximum concentration was 3.4 h. Elimination half-life was 7.3 h, mean residence time 7.4 h, and apparent volume of distribution 5.7 L/kg. Achieved plasma concentrations exceeded those associated with psychomotor impairment in people although pharmacodynamic effects have not been investigated in pigs. A simulated oral regimen consisting of 0.35 mg/kg administered every 8 h to pigs would achieve plasma concentrations above 32 ng/mL which are shown to produce psychomotor impairment in people. Further studies to test the clinical efficacy of these dosages in commercial and miniature pigs are warranted.

Pharmacokinetics of nalbuphine administered intravenously and subcutaneously in goats (Capra aegagrus hircus).

The purpose of this study was to evaluate the pharmacokinetics (PK) of intravenously (IV) and subcutaneously (SC) administered nalbuphine in domestic goats. Nalbuphine hydrochloride was administered at 0.8 mg/kg for both IV and SC routes in six goats with a minimum of 10-day washout period between sample collection phases. Eighteen plasma samples were collected over a 36-hour period, analyzed using reverse phase high-performance liquid chromatography (HPLC). Plasma data were analyzed using compartmental and noncompartmental approaches. Following IV nalbuphine administration, elimination half-life, area under the plasma concentration time curve from time 0 to infinity (AUC0 - ∞), concentration at time zero (C0), and total body clearance were 120.4 ± 39.1 (min-1 ± SD), 17311.01 ± 7227.32 (min·ng·mL-1 ± SD), 675.6 ± 337.13 (ng·mL-1 ± SD), and 44.5 ± 13.8 (mL·min-1·kg-1 ± SD), respectively. After SC nalbuphine administration, elimination half-life, area under the plasma concentration time curve from time 0 to infinity (AUC0 - ∞), and maximum plasma drug concentration were 129 ± 52.9 (min-1 ± SD), 20826.5 ± 14376.2 (min·ng·mL-1), and 368.03 ± 503.78 (ng·mL-1). Calculated bioavailability for the SC route was 138 ± 126 (% ± SD). Nalbuphine in goats is characterized by rapid elimination and high subcutaneous bioavailability and may be a safe analgesic opioid option in goats in the future.

Enhancing prosthesis stability at the cricoid cartilage in equine laryngoplasty using 3-D-printed laryngeal clamps: An ex vivo model study.

OBJECTIVE: To assess a three-dimensional (3-D)-printed laryngeal clamp (LC) designed to enhance the anchoring of laryngeal prostheses at the cricoid cartilage. STUDY DESIGN: Ex vivo biomechanical study. SAMPLE POPULATION: A total of 22 equine larynges. METHODS: Two experimental groups included larynges with standard prosthetic laryngoplasty (PL; n = 10) and larynges with prosthetic laryngoplasty modified with laryngeal clamps (PLLC; n = 10). All constructs underwent 3000 cycles of tension loading and a single tension to failure. Recorded biomechanical parameters included maximum load, actuator displacement, and construct failure. Finite element analysis (FEA) was performed on one PL and one PLLC construct. RESULTS: The maximum load at single tension to failure was 183.7 ± 46.8 N for the PL construct and 292.7 ± 82.3 N for the PLLC construct (p = .003). Actuator displacement at 30 N was 1.7 ± 0.5 mm and 2.7 ± 0.7 mm for the PL and PLLC constructs, respectively (p = .011). The cause of PL constructs failure was mostly tearing through the cartilage whereas the PLLC constructs failed through fracture of the cricoid cartilage (p = .000). FEA revealed an 11-fold reduction in the maximum equivalent plastic strain, a four-fold reduction in maximum compressive stress, and a two-fold increase in the volume of engaged cartilage in PLLC constructs. CONCLUSION: The PLLC constructs demonstrated superior performance in biomechanical testing and FEA compared to standard PL constructs. CLINICAL SIGNIFICANCE: The use of 3-D-printed laryngeal clamps may enhance the outcomes of laryngoplasty in horses. In vivo studies are necessary to determine the feasibility of performing laryngoplasty using the laryngeal clamp in horses.

Pharmacokinetics of a single oral dose of grapiprant in juvenile pigs (Sus scrofa domestica).

Both pet and research pigs can suffer from some degree of pain from surgery, injuries, or osteoarthritis (OA). Despite this, there is a paucity of data on safe and effective analgesia agents in pigs. Grapiprant is an EP4 antagonist that blocks the action of the pro-inflammatory prostanoid, PGE2 . It has shown efficacy in attenuating pain associated with ovariohysterectomy and OA in dogs. However, there are no data regarding grapiprant in pigs. Therefore, the pharmacokinetic profile of orally administered grapiprant to juvenile pigs (Sus scrofa domestica) was evaluated in this study. Seven juvenile pigs received 12 mg/kg grapiprant orally. Blood was collected from an indwelling jugular catheter using the push-pull method at set timepoints up to 48 hours. Sample analysis was performed with high-performance liquid chromatography. Mean grapiprant plasma concentration was 164.3 ± 104.7 ng/mL which occurred at 0.8 ± 0.3 h. This study demonstrated that grapiprant concentrations consistent with analgesia in dogs were reached at this dosage in pigs. Further studies are needed to evaluate the efficacy of grapiprant in pigs.

Pharmacokinetics of intramuscular maropitant in pigs (Sus scrofa domesticus).

Pigs are at risk of vomiting from medical conditions as well as the emetic side effects of drugs administered for peri-operative manipulations, but there is a lack of pharmacokinetic data for potential anti-emetic therapies, such as maropitant, in this species. The main objective of this study was to estimate plasma pharmacokinetic parameters for maropitant in pigs after a single intramuscular (IM) administration dosed at 1.0 mg/kg. A secondary objective was to estimate pilot pharmacokinetic parameters in pigs after oral (PO) administration at 2.0 mg/kg. Maropitant was administered to six commercial pigs at a dose of 1.0 mg/kg IM. Plasma samples were collected over 72 h. After a 7-day washout period, two pigs were administered maropitant at a dose of 2.0 mg/kg PO. Maropitant concentrations were measured via liquid chromatography/mass spectrometry (LC-MS/MS). A non-compartmental analysis was used to derive pharmacokinetics parameters. No adverse events were noted in any of the study pigs after administration. Following single IM administration, maximum plasma concentration was estimated at 412.7 ± 132.0 ng/mL and time to maximum concentration ranged from 0.083 to 1.0 h. Elimination half-life was estimated at 6.7 ± 1.28 h, and mean residence time was 6.1 ± 1.2 h. Volume of distribution after IM administration was 15.9 L/kg. Area under the curve was 1336 ± 132.0 h*ng/mL. The relative bioavailability of PO administration was noted to be 15.5% and 27.2% in the two pilot pigs. The maximum systemic concentration observed in the study pigs after IM administration was higher than what was observed after subcutaneous administration in dogs, cats, or rabbits. The achieved maximum concentration exceeded the concentrations for anti-emetic purposes in dogs and cats; however, a specific anti-emetic concentration is currently not known for pigs. Further research is needed into the pharmacodynamics of maropitant in pigs to determine specific therapeutic strategies for this drug.

Clinical presentation, diagnostics, treatment, and outcome of goats diagnosed with presumptive cerebrospinal nematodiasis at a veterinary teaching hospital.

This retrospective study describes clinical presentation, diagnostic approach, treatment, and outcome for goats with presumptive cerebrospinal nematodiasis. A presumptive diagnosis was made based on neurologic signs, results of cerebrospinal fluid analysis, and response to treatment. Six goats were identified that met inclusion criteria. Cerebrospinal fluid analysis revealed eosinophilic pleocytosis (total nucleated cell count: 12 to 430/µL, 33 to 89% eosinophils). All 6 goats were treated with fenbendazole and anti-inflammatory drugs (NSAIDs ± corticosteroids) and 4 received physical rehabilitation therapy. At discharge or follow-up, all 6 goats were ambulatory and had minimal neurologic deficits. Key clinical message: In goats, cerebrospinal nematodiasis caused by Parelaphostrongylus tenuis is often a presumptive diagnosis based on neurologic signs, shared habitat with white-tailed deer, eosinophilic pleocytosis, and response to anthelmintic therapy. Presumptive cases in goats have many similarities to confirmed cases in camelids. Further study is indicated to characterize the clinical signs and optimize the diagnosis and treatment of goats infected with P. tenuis.

Présentation clinique, diagnostic, traitement et devenir des chèvres diagnostiquées avec une nématodose cérébro-spinale présumée dans un hôpital d'enseignement vétérinaire. Cette étude rétrospective décrit la présentation clinique, l'approche diagnostique, le traitement et les résultats pour des chèvres atteintes de nématodose cérébro-spinale présumée. Un diagnostic présomptif a été posé sur la base des signes neurologiques, des résultats de l'analyse du liquide céphalo-rachidien et de la réponse au traitement. Six chèvres ont été identifiées qui répondaient aux critères d'inclusion. L'analyse du liquide céphalo-rachidien a révélé une pléocytose éosinophile (nombre total de cellules nucléées : 12 à 430/µL, 33 à 89 % d'éosinophiles). Les six chèvres ont été traitées avec du fenbendazole et des anti-inflammatoires (AINS ± corticostéroïdes) et quatre ont reçu une thérapie de réadaptation physique. À la sortie ou au suivi, les six chèvres étaient ambulatoires et présentaient des déficits neurologiques minimes.Message clinique clé :Chez les chèvres, la nématodose cérébro-spinale causée par Parelaphostrongylus tenuis est souvent un diagnostic présomptif basé sur des signes neurologiques, un habitat partagé avec des cerfs de Virginie, une pléocytose éosinophile et une réponse à un traitement anthelminthique. Les cas présumés chez les chèvres présentent de nombreuses similitudes avec les cas confirmés chez les camélidés. Une étude plus approfondie est indiquée pour caractériser les signes cliniques et optimiser le diagnostic et le traitement des chèvres infectées par P. tenuis.(Traduit par Dr Serge Messier).

Comparison between barbed and conventional sutures for longitudinal thelotomy closure in an ex-vivo bovine model.

Objective: To determine differences in suture time and bursting strength on a longitudinal thelotomy closure using innovative barbed versus conventional smooth suture materials. Sample population: Twenty-four teats from 6 udders of culled beef cows. Study design: Experimental ex-vivo surgical study. Methods: Thelotomies (length: 2 cm) were performed on every teat and randomly allocated to closure with either a 3-0 bidirectional barbed suture for both mucosa and connective layers or a conventional 3-layer suture, using 3-0 smooth polydioxanone. For both groups, skin was closed with 2-0 polypropylene monofilament suture. Duration of suturing time for inner layers and bursting strength of the repair were recorded and compared. Results: Suturing was faster with barbed versus conventional sutures (527.7 ± 64.5 versus 727.1 ± 60.7 s, respectively; P < 0.0001). However, bursting strength was not significantly different between the 2 types of sutures. Conclusion: Using the barbed suture significantly reduced the time required to suture the mucosa and conjunctiva layers, with no significant difference between sutures in their bursting strength. Clinical significance: Bidirectional barbed suture material is suitable for closure of thelotomies in cattle.

Comparaison entre les sutures barbelées et conventionnelles pour la fermeture de la thélotomie longitudinale dans un modèle bovin ex-vivo. Objectif: Déterminer les différences de temps de suture et de résistance à l'éclatement sur une fermeture de thélotomie longitudinale en utilisant des matériaux de suture barbelés innovants par rapport aux matériaux de suture lisses conventionnels. Échantillon de population: Vingt-quatre tétines provenant de six pis de vaches de boucherie réformées. Étudier le design: Étude chirurgicale expérimentale ex-vivo. Méthodes: Des thélotomies (longueur : 2 cm) ont été réalisées sur chaque trayon et attribuées au hasard à la fermeture avec soit une suture barbelée bidirectionnelle 3-0 pour la muqueuse et les couches de tissu conjonctif, soit une suture conventionnelle à trois couches, utilisant du polydioxanone lisse 3-0. Pour les deux groupes, la peau a été fermée avec une suture en monofilament de polypropylène 2-0. La durée du temps de suture pour les couches internes et la résistance à l'éclatement de la réparation ont été enregistrées et comparées. Résultats: La suture était plus rapide avec les sutures barbelés par rapport aux sutures conventionnelles (527,7 ± 64,5 contre 727,1 ± 60,7 s, respectivement; P < 0,0001). Cependant, la résistance à l'éclatement n'était pas significativement différente entre les deux types de sutures. Conclusion: L'utilisation de la suture barbelée a considérablement réduit le temps nécessaire pour suturer les couches de la muqueuse et de tissu conjonctif, sans différence significative entre les sutures dans leur résistance à l'éclatement. Signification clinique: Le matériau de suture barbelé bidirectionnel convient à la fermeture des thélotomies chez les bovins.(Traduit par Dr Serge Messier).

Tensile properties of synthetic, absorbable monofilament suture materials before and after incubation in phosphate-buffered saline.

OBJECTIVE: To compare tensile properties of synthetic, absorbable, monofilament suture material before and after incubation in phosphate-buffered saline (PBS). STUDY DESIGN: Two sizes (2-0 and 3-0) of Biosyn, Maxon, Monocryl, PDS II, Securocryl, and Securodox were tested. SAMPLE POPULATION: Ten suture loops per group. METHODS: Tensile strength, elongation, and modulus of suture loops were measured at baseline and after 7, 14, 21, or 28 days of incubation in PBS. RESULTS: Size, suture material, and size × suture material interaction influenced maximum breaking load, maximum elongation, and modulus of elasticity. At baseline, 2-0 and 3-0 Maxon had the highest breaking loads (111.67 N and 79.71 N, respectively) for their size, and 2-0 PDSII and 3-0 Securodox had the lowest (68.71 N and 48.73 N, respectively). Maxon 2-0 and 3-0 had the greatest elongations (9.68 mm and 8.45 mm, respectively) for their size, and 2-0 Biosyn and 3-0 Securocryl had the least (7.21 mm and 6.58 mm, respectively). Biosyn 2-0 and 3-0 had the highest modulus. With incubation, Maxon (2-0), PDS II (2-0, 3-0), and Securodox (2-0, 3-0) maintained or gained strength over 4 weeks. Strengths of 2-0 and 3-0 Biosyn and 3-0 Maxon were maintained for 2 weeks, while Monocryl and Securocryl lost 20% to 44% of baseline strength within 1 week and 60% to 72% within 2 weeks. Day 7 strengths of 2-0 Biosyn and 2-0 Monocryl were greater than baseline strength of 2-0 PDS II. Strength of 3-0 Biosyn at day 14 was greater than strength of Monocryl at days 7 and 14 and greater than strength of 3-0 PDS II, 3-0 Securodox, and 3-0 Securocryl at baseline and days 7 and 14. CONCLUSION: Suture tensile properties varied with suture size, composition, and brand. At baseline, Maxon suture had the greatest strength and elongation, and Biosyn had the greatest stiffness. CLINICAL SIGNIFICANCE: Tensile strength retention, when reported as a percentage of original strength, provides insufficient information for comparison of suture tensile properties.

Multicenter retrospective study of complications and risk factors associated with castration in 106 pet pigs.

Castration of pet pigs is becoming a commonly performed procedure. However, little information is available regarding surgical techniques and complications. Medical records of 106 pet pigs admitted to 3 teaching hospitals for castration were reviewed. All descended testicles were approached via pre-scrotal skin incisions, which were either closed (59.4%) or left open (22.6%). The inguinal rings were closed in 42% of cases. Of the 106 pet pigs, 4.7% developed a complication after surgery, which consisted of peri-incisional swelling. Pigs which underwent inguinal ring closure were 6.6 times more likely to develop a post-operative complication (confidence interval: 1.16 to infinity, P = 0.035). Age and weight at time of castration were not significantly associated with complications (P = 0.698 and P = 0.685, respectively). The results from this retrospective study suggest that castration in pet pigs is a safe procedure with a minimal rate of complications.

Étude rétrospective multicentre des complications et facteurs de risque associés avec la castration de 106 porcs miniatures. La castration de porcs miniatures est en voie de devenir une procédure effectuée couramment. Toutefois, peu d'informations sont disponibles concernant les techniques chirurgicales et les complications. Les dossiers médicaux de 106 porcs miniatures admis à trois hôpitaux vétérinaires d'enseignement pour castration ont été revus. Tous les testicules descendus furent approchés via des incisions cutanées préscrotales, qui furent soient fermées (59,4 %) ou laissées ouvertes (22,6 %). Les anneaux inguinaux étaient fermés dans 42 % des cas. Parmi les 106 porcs miniatures, 4,7 % ont développé des complications après la chirurgie, consistant en oedème péri-incisionnel. Les porcs qui ont dû subir une fermeture de l'anneau inguinal étaient 6,6, fois plus à risque de développer des complications post-opératoires (intervalle de confiance : 1,16 à l'infini, P = 0,035). L'âge et le poids au moment de la castration n'étaient pas associés de manière significative avec des complications (P = 0,698 et P = 0,685, respectivement). Les résultats de la présente étude rétrospective suggèrent que la castration de porcs miniatures est une procédure sécuritaire avec un taux minime de complications.(Traduit par Dr Serge Messier).

Long-term mechanical milking status of lacerated teat repaired surgically in cattle: 67 cases (2003-2013).

This study evaluated the long-term prognosis of return to normal mechanical milking after reconstructive teat surgery and determined the factors that have an impact on the outcome. A retrospective study of 67 dairy cows with teat lacerations was performed. Milking status at discharge and at long-term follow-up was adequate for 83% and 75% of the cows, respectively. No statistically significant differences were detected between the long-term prognosis and the age of the cow, the stage of lactation at presentation, or the configuration of the laceration. Lacerations repaired more than 24 hours after the trauma were more frequently associated with a negative outcome (P = 0.05). Mastitis was the most frequent complication (n = 17) and had a statistically significant negative impact on long-term prognosis (P = 0.02). Reconstructive surgery of lacerated teat in dairy cows can help establish return to normal mechanical milking.

Évaluation du pronostic à long terme en regard de la traite mécanique des trayons lacérés réparés chirurgicalement chez la vache : 67 cas (2003­2013). Les objectifs de cette étude sont d'évaluer le pronostic à long terme, en regard de la traite mécanique, suivant la reconstruction d'un trayon lacéré et de déterminer les critères associés à un pronostic négatif. Une étude rétrospective sur 67 vaches laitières a été réalisée. La traite mécanique était adéquate pour 83 et 75 % des vaches à leur sortie de l'hôpital et lors du suivi à long terme. Pas de différences statistiques ont été trouvées entre le pronostic à long terme et l'âge des vaches, leur stade de lactation et la configuration de la lacération. Les lacérations réparées plus de 24 heures après le trauma avaient un pronostic moins bon (P = 0,05). La complication la plus fréquente était la mammite (n = 17). Elle avait un effet négatif sur le pronostic à long terme (P = 0,02). Reconstruire chirurgicalement un trayon lacéré peut rétablir la traite mécanique.(Traduit par les auteurs).

Effect of cyclic loading on the ultimate tensile strength of small metallic suture anchors used for attaching artificial tendons in rabbits.

Background ­: Suture anchor failures can lead to revision surgeries which are costly and burdensome for patients. The durability of musculoskeletal reconstructions is therefore partly affected by the design of the suture anchors. Purpose ­: The purpose of the study was to quantify the strength of different suture anchors whose sizes are suitable for attaching artificial Achilles and tibialis cranialis tendons in a rabbit model, as well as determine the effect of cyclic loading on the anchoring strength. Method ­: Four anchors (two with embedded eyelet and two with raised eyelet, n=5 per group) were tested with cyclical loading (1000 cycles and 4.5 mm/sec) and without cycling, to inform the failure loads and mode of failure of the suture anchors. An eyebolt screw with smooth eyelet was used as a control for the test groups. Results ­: All samples in all groups completed 1000 cycles and failed via suture breakage in both test conditions. All anchors had failure loads exceeding the peak Achilles tendon force in rabbits during hopping gait. The data analysis showed an effect of anchor type on the maximum tensile force at failure (F max ) in all suture categories but not an effect of loading condition. Also, the Anika anchor had a significantly less adverse effect on suture strength compared to Arthrex anchor (p=0.015), IMEX anchor (p=0.004) and Jorvet anchor (p<0.001). We observed a greater percentage of failure at the mid-section for the anchors with the raised eyelets compared to the anchors with embedded eyelets, which all failed at the knot. Conclusion ­: Anchors with embedded eyelets had clinically preferred mode of failure with less adverse effects on suture and, may be more reliable than anchors with raised eyelets for attaching artificial Achilles and tibialis cranialis tendons in rabbits.

Tooth Root Abscess and Mandibular Infections in Old World Camelids: 3 Cases.

There are limited reports of mandibular infections and tooth root abscesses in camels (Old World Camelids). This is in contrast to multiple reports and case series detailing diagnosis, management, and therapy of similar infections in New World Camelids such as llamas and alpacas. The purpose of this case series is to present three cases of camels in North America with these infections and to detail the diagnostics, therapeutic interventions, management, and follow-up of these cases. Radiography was utilized in all three cases, as was sedation and/or anesthesia. Similar to llamas, florfenicol was used for antimicrobial therapy and flunixin meglumine was utilized as a nonsteroidal anti-inflammatory. Some degree of lavage was required for the management of each case. Clinicians should be aware of the potential need for sedation, diagnostic imaging, culture, and extended therapies for the treatment of mandibular and tooth root infections in camels as comparatively described for llamas and alpacas.

Pharmacokinetics and pharmacodynamics of intravenously and subcutaneously administered pantoprazole in sheep (Ovis aries).

Abomasal ulcers are recognized in sheep of all ages, but research regarding therapeutic interventions is limited. Proton Pump Inhibitors (PPIs) such as pantoprazole, are clinically used with a paucity of evidence regarding efficacy in mature sheep. Intravenous and subcutaneously administered pantoprazole dosed at 1.0 mg/kg in adult sheep will increase the pH of abomasal fluid compared to pre-administration baseline. The objectives were to assess the effect of pantoprazole, after single and multiple administration, on abomasal fluid pH in adult sheep. A third objective was to describe the pharmacokinetic parameters of IV and SC pantoprazole. Four clinically healthy adult Southdown ewes previously fitted with a gastrostomy tube in the abomasum were utilized in this randomized, 2-way cross-over trial. Ewes received pantoprazole (1.0 mg/kg) as a single and 3-dose regimen (every 24 hours). After a 10 day washout period the reverse treatment was applied. Blood for analysis of pantoprazole concentration was collected intermittently for 24 hours, and abomasal fluid pH was measured at intervals for a 96-hour period. The pH of the abomasal fluid was higher in pantoprazole treatments for up to 24 hours after dosing. Following intravenous administration of pantoprazole to study ewes, elimination half-life, volume of distribution, and clearance of pantoprazole was estimated as 3.29 hours, 0.35 L/kg, and 65.26 mL/hr/kg respectively. After subcutaneous dosing, maximum concentration, time to maximum concentration, half-life of elimination, and volume of distribution, were estimated as 2604 ng/mL, 0.55 hours, 2.48 hours, and 0.37 L/kg. Additionally, the bioavailability was estimated as 83.33%. Pantoprazole administered IV or SC may be useful for treatment or prevention of abomasal ulcers in adult sheep.

Milk flow obstruction caused by varicose vein of the teat in dairy cattle.

OBJECTIVE: To describe varicose vein as a cause of obstruction of the teat cistern in dairy cattle and to report therapeutic options and outcome. STUDY DESIGN: Retrospective case series. ANIMALS: Dairy cows (n = 22). METHODS: Medical records (1998-2011) of dairy cows admitted for milking difficulties caused by a teat varicose vein were reviewed. Three treatment approaches were used: sclerotherapy, ligation of the vein associated with sclerotherapy, and phlebectomy. Long-term outcome was obtained ≥ 6 months after treatment and defined as a milking improvement. Descriptive statistics were used to determine the population at risk and a chi square test was used to evaluate the relationship between treatments and outcomes. RESULTS: Twenty-four teats (22 cows) had a varicose vein. Forequarters were more frequently affected than rear quarters (P < .01). Three sclerotherapies, 12 ligations associated with sclerotherapy and 6 phlebectomies were performed. Five veins were not treated. Overall prognosis with treatment was good (84%) at ≥ 6 months and was not significantly different between treatment types (P = .38). Recurrence of the obstruction by the varicose vein occurred in 3 of 19 teats. CONCLUSIONS AND CLINICAL RELEVANCE: Several surgical options are available for treatment of teat varicose veins. The overall prognosis of return to normal milking is good.

Delayed Urethral Obstruction after Migration of a Ballistic Pellet in an Alpine Wether.

A one-year-old alpine wether was presented for emergency evaluation of stranguria. Diagnostics identified a moderately distended bladder and mild dehydration. Preliminary lateral radiographs identified two metallic structures consistent with projectile pellets in the pelvic and perineal regions and no evidence of radiopaque uroliths. A tube cystostomy was performed, and a contrast urethrogram revealed one of the pellets in the perineal region was in proximity to the urethral obstruction. Subsequent radiography and ultrasound identified the pellet as being within the lumen of the urethra. Examination of the trichotomized skin revealed two scars, including a scar over the paralumbar fossa in the region of the urinary bladder suggestive of a projectile injury. The pellet was removed by a perineal urethrotomy. The patient was able to spontaneously urinate after urethrotomy, passed a tube cystostomy challenge two weeks after surgery, and was discharged. No complications were reported. While uncommon in the veterinary and comparative medical literature, clinicians should consider the potential for projectile pellets to migrate into the urinary tract after initial injury.

Changes in tibial cortical dimensions and density associated with long-term locking plate fixation in goats.

PURPOSE: Cortical porosis, secondary to either vascular injury or stress-shielding, is a comorbidity of fracture fixation using compression bone plating. Locking plate constructs have unique mechanics of load transmission and lack of reliance on contact pressures for fixation stability, so secondary cortical porosis adjacent to the plate has not been widely investigated. Therefore, this study aimed to assess the effects of long-term locking plate fixation on cortical dimensions and density in a caprine tibial segmental ostectomy model. METHODS: Data was acquired from a population of goats enrolled in ongoing orthopedic research which utilized locking plate fixation of 2 cm tibial diaphyseal segmental defects to evaluate bone healing over periods of 3, 6, 9, and 12 months. Quantitative data included tibial cortical width measurements and three-dimensionally reconstructed slab density measurements, both assessed using computed tomographic examinations performed at the time of plate removal. Additional surgical and demographic variables were analyzed for effect on cortical widths and density, and all cis-cortex measurements were compared to both the trans-cortex and to the contralateral limbs. RESULTS: The tibial cis-cortex was significantly wider and more irregular than the trans-cortex at the same level. This width asymmetry differed in both magnitude and direction from the contralateral limb. The bone underlying the plate was significantly less dense than the trans-cortex, and this cortical density difference was significantly greater than that of the contralateral limb. These cortical changes were independent of both duration of fixation and degree of ostectomy bone healing. CONCLUSIONS: This study provides evidence that cortical bone loss consistent with cortical porosity is a comorbidity of locking plate fixation in a caprine tibial ostectomy model. Further research is necessary to identify risk factors for locking-plate-associated bone loss and to inform clinical decisions in cases necessitating long-term locking plate fixation.

Blood parameters associated with residual feed intake in beef heifers.

Blood chemistry may provide indicators to greater feed efficient cattle. As a side objective to previous research, 17 Angus heifers approximately two years old underwent a feed efficiency trial to determine residual feed intake (RFI) and identify variation in blood chemistry in beef cattle divergent in feed efficiency. Heifers were categorized as high- or low-RFI based ± 0.25 standard deviations around mean RFI. Blood samples were analyzed using an i-STAT handheld blood analyzer to measure sodium, potassium, glucose, blood urea nitrogen (BUN), creatinine, hematocrit, and hemoglobin. BUN was greater in high-RFI heifers (µ = 8.7 mg/dL) contrasted to low-RFI heifers (µ = 6.5 mg/dL; P = 0.01), whereas glucose was greater in low-RFI heifers (µ = 78.1 mg/dL) contrasted to high-RFI heifers (µ = 82.0 mg/dL; P = 0.05). No other blood chemistry parameters differed by RFI. The greater abundance of BUN in high-RFI heifers may indicate inefficient utilization of protein or mobilization of tissue protein for non-protein use. Greater blood glucose concentrations in low-RFI heifers may indicate greater utilization of energy precursors, such as volatile fatty acids, or metabolites. These data suggest there are readily measurable indicators of physiological variation in nutrient utilization; however, this warrants additional studies to explore.

In vitro analysis and in vivo assessment of fracture complications associated with use of locking plate constructs for stabilization of caprine tibial segmental defects.

PURPOSE: Locking plate fixation of caprine tibial segmental defects is widely utilized for translational modeling of human osteopathology, and it is a useful research model in tissue engineering and orthopedic biomaterials research due to its inherent stability while maintaining unobstructed visualization of the gap defect and associated healing. However, research regarding surgical technique and long-term complications associated with this fixation method are lacking. The goal of this study was to assess the effects of surgeon-selected factors including locking plate length, plate positioning, and relative extent of tibial coverage on fixation failure, in the form of postoperative fracture. METHODS: In vitro, the effect of plate length was evaluated using single cycle compressive load to failure mechanical testing of locking plate fixations of caprine tibial gap defects. In vivo, effects of plate length, positioning, and relative tibial coverage were evaluated using data from a population of goats enrolled in ongoing orthopedic research which utilized locking plate fixation of 2 cm tibial diaphyseal segmental defects to evaluate bone healing over 3, 6, 9, and 12 months. RESULTS: In vitro, no significant differences in maximum compressive load or total strain were noted between fixations using 14 cm locking plates and 18 cm locking plates. In vivo, both plate length and tibial coverage ratio were significantly associated with postoperative fixation failure. The incidence of any cortical fracture in goats stabilized with a 14 cm plate was 57%, as compared with 3% in goats stabilized with an 18 cm plate. Craniocaudal and mediolateral angular positioning variables were not significantly associated with fixation failure. Decreasing distance between the gap defect and the proximal screw of the distal bone segment was associated with increased incidence of fracture, suggesting an effect on proximodistal positioning on overall fixation stability. CONCLUSIONS: This study emphasizes the differences between in vitro modeling and in vivo application of surgical fixation methods, and, based on the in vivo results, maximization of plate-to-tibia coverage is recommended when using locking plate fixation of the goat tibial segmental defect as a model in orthopedic research.

The pharmacokinetics and pharmacodynamics of esomeprazole in sheep after intravenous dosing.

Abomasal (gastric) ulceration is a morbidity in sheep, and currently, there is a paucity of pharmacokinetic and pharmacodynamic data for gastroprotectant drugs reported for this species. The proton pump inhibitor esomeprazole has been used in small animal and human patients for gastroprotection via increasing the gastric pH. The objective of this study was to report the pharmacokinetic parameters and pharmacodynamic effect of esomeprazole in sheep after single intravenous dosing. Four healthy adult Southdown cross ewes had blood collected over a 24 h time period after single intravenous dosing of esomeprazole at 1.0 mg/kg. Abomasal fluid was sampled over 24 h before and after esomeprazole administration. Plasma samples were analyzed for concentrations of esomeprazole and the esomeprazole metabolite, esomeprazole sulfone by high performance liquid chromatography. Pharmacokinetic and pharmacodynamic data were evaluated with specialized software. Esomeprazole was rapidly eliminated after IV administration. Elimination half-life, area under the curve, initial concentration (C0), and clearance were 0.2 h, 1,197 h*ng/mL, 4,321 ng/mL, and 0.83 mL/h/kg, respectively. For the sulfone metabolite elimination half-life, area under the curve and maximum concentration were 0.16 h, 22.5 h*ng/mL, and 65.0 ng/mL, respectively. Abomasal pH was significantly elevated from 1 to 6 h after administration and remained above 4.0 for at least 8 h after administration. No adverse effects were noted in these sheep. Esomeprazole was rapidly eliminated in sheep, similar to goats. Abomasal pH was increased, but future studies will be necessary to develop a clinical management approach to the use of esomeprazole in sheep.