Antioxidant supplementation,effect on post‐thaw spermatozoan function in three sturgeon species

High levels of reactive oxygen species (ROS), which may be associated with reduced sperm quality, can be detected during cryopreservation of sperm of some species. Our objective was to investigate whether the addition of antioxidants to cryopreservation extenders influenced post‐thaw sperm characteristics and fertility in Acipenser dabryanus, Acipenser sinensis and Acipenser baerii. Prior to freezing, sperm samples were diluted with a base extender as control or in extender supplemented with catalase (CAT), glutathione (GSH), cysteine (NAC), ascorbic acid (VC) or their paired combinations. Protective concentrations of CAT, GSH and VC in the three species were 25 U/ml, 0.25‐0.5 mg/ml and 0.5 mg/ml, respectively. Cysteine showed no protective effect against ROS. The addition of CAT, GSH and VC positively affected either acrosome or membrane integrity of post‐thawed sperm in the three species, as well as spermatozoan motility in A. sinensis. The combination of antioxidants did not show a positive synergistic effect. This study suggested that the use of antioxidants in the cryopreservation of sturgeon sperm has potential to decrease intracellular ROS, and consequently preserve acrosome and membrane integrity, as well as spermatozoan motility.     

Cardiopulmonary and Analgesic Effects of Epidural Lidocaine, Alfentanil, and Xylazine in Pigs Anesthetized With Isoflurane

To determine cardiopulmonary and analgesic effects of lidocaine, alfentanil, and xylazine in pigs anesthetized with isoflurane, 18 healthy Landrace-Large White pigs were studied (six for each drug). General anesthesia was induced with isoflurane in O₂ and maintained with 1% to 1.2% end-tidal ISO, ensuring presence of a pain response before epidural drug administration. Heart rate (HR), arterial blood pressures (AP), cardiac output (CO), pulmonary arterial pressure, pulmonary capillary wedge pressure (PCWP), central venous pressure, respiratory rate (RR), tidal volume (TV), minute volume (MV), arterial blood gas data, core temperature (CT), and analgesic effects (by pricking the lumbar area and the abdominal wall) were determined at various times (2, 5, 15, 30, 45, 60, and 90 minutes) after epidural administration of lidocaine (5 μg/kg), alfentanil (5 μg/kg), or xylazine (0.2 mg/kg), all diluted in NaCl 0.9% to 0.5 mL/kg. Statistical analysis included two-way analysis of variance for repeated measures and the least significant difference test for determining differences among means. A probability level of P <.05 was used. The following results were statistically significant decreases in systolic AP, HR, TV, RR, MV, CT, pH, PaO₂, and TCO₂ and increases in PCWP, PaCO₂, and HCO₃ after LID. After ALF, only CT and HCO₃ decreased. Core temperature and TV decreased after XYL. Lidocaine provided 45 to 60 minutes of analgesia. Alfentanil had no analgesic effects, and xylazine provided 90 minutes of analgesia. The authors conclude that xylazine, when injected epidurally, provides suitable analgesia in isoflurane-anesthetized pigs.     

COMPUTED TOMOGRAPHY OF THE NORMAL FELINE NASAL CAVITY AND PARANASAL SINUSES

Computed tomography (CT) images of the feline nasal cavity and paranasal were acquiredfrom noraml adult cats. Good resolutin and amatomic detail were obtained from the CT images using soft tissue formatting. A desciption of normal feline nasal cavity and paranasal sinus anatomy using CT is presented.     

Efficacy of an ivermectin and pyrantel pamoate combination against adult hookworm, Ancylostoma braziliense, in dogs

A chewable tablet incorporating ivermectin and pyrantel was tested in 12 Beagle dogs for efficacy against the adult hookworm, Ancylostoma braziliense. The dogs were administered infective larvae of A braziliense orally. Twenty-one days after infection the dogs were weighed and allocated randomly to receive either an oral treatment with ivermectin and pyrantel in a beef-based chewable tablet or no treatment. The chewable tablet was a commercially available product, which was made to deliver ivermectin at 6 μg/kg and pyrantel at 5.0 mg/kg to each dog. Seven days after treatment the dogs were euthanased, necropsied, and examined for adult hookworms. At necropsy, no adult A braziliense was observed in any of the 6 treated dogs and all 6 dogs that had been left untreated were infected with adult A braziliense (range, 48 to 161). It was concluded that this combination product is 100% efficacious against adult A braziliense.     

MAGNETIC RESONANCE IMAGING OF THE BRAIN AND COELOMIC CAVITY OF THE DOMESTIC PIGEON (Columba livia domestica)

The technical feasibility of performing magnetic resonance imaging (MRI) in domestic pigeons was investigated. Imaging was performed with a 1.5 Tesla magnet using a human knee surface coil. The head and coelomic cavity of isoflurane-anesthetized birds were imaged in the dorsal, sagittal, and transverse planes to produce T1-weighted, T2-weighted, and contrast-enhanced T1-weighted images. The birds were then euthanatized, formalin perfused, frozen, and sectioned in the corresponding anatomic planes. The anatomy defined by MRI was correlated with gross anatomic sections made from the same birds. The following CNS structures were identified: cerebral hemispheres, cerebellum, optic chiasm, optic lobes, brain stem, and cranial spinal cord. The cornea, lens, and vitreous were also well differentiated in dorsal section MRI's. The abdominal organs identified included proventriculus, ventriculus, intestines, cloaca, liver, kidneys, spleen, testes, and ovary. The hepatic and renal vasculature were well defined.     

The Pathogenesis of Reactive Systemic Amyloidosis

The diagnosis of amyloidosis is based on the presence of extracellular tissue deposits of proteinaceous material that demonstrate a characteristic green color when stained with Congo red and viewed under polarized light. Several different proteins are amyloidogenic but, in domestic animals, spontaneously occurring systemic amyloidosis is reactive in nature and characterized by the presence of amyloid protein AA. This type of systemic amyloidosis may occur secondary to chronic inflammatory or neoplastic disease, but in many instances no predisposing disease is found. A sustained increase in the serum concentration of serum amyloid A protein (SAA) is necessary but not sufficient for the development of reactive amyloidosis. Other inherited and acquired host-related factors are likely to be important in the development of reactive amyloidosis because this condition develops in few patients with chronic inflammatory disease. The tissue tropism of amyloid deposits varies with the amyloid protein itself and species affected. The consequences of amyloidosis for the host depend upon the tissues involved and the response of these tissues to the presence of the amyloid deposits. In domestic animals, reactive systemic amyloidosis is nephropathic, leading to end-stage renal disease, and the clinical presentation is that of uremia.     

Transplantation of the Canine Distal Ulna as a Free Vascularized Bone Graft

An autogenous free vascular bone graft of the canine distal ulna was evaluated. The vascularity of the graft was based on a musculoperiosteal sheath supplied solely by the caudal interosseous artery and vein. Four autogenous heterotopic (ulna to tibia) vascular transfers were performed. Two avascular transfers were performed to provide baseline criteria from which the success of vascularized transfers could be assessed. Clinical lameness evaluation, serial radiographs, bone scintigraphy, and sequential fluorochrome bone labeling were performed after surgery in both vascular and avascular transfers. All dogs were free of lameness in the donor limb by the 26th postoperative day. Serial radiographs revealed rapid graft incorporation and hypertrophy in all vascularized grafts and severe bone resorption in nonvascularized grafts. Histology, microangiography, and evaluation of fluorochrome bone labels were performed 90 days after surgery to determine graft viability, incorporation and temporal remodeling patterns. Microangiography and fluorochrome assessment complemented the histological findings. Based on these findings the distal ulnar bone graft was determined to be both viable and structurally adequate for selected cases of long bone reconstruction.     

Transsphenoidal Hypophysectomy in Beagle Dogs: Evaluation of a Microsurgical Technique

Objective — Assessment of a microsurgical technique for transsphenoidal hypophysectomy in dogs.
Study Design — Prospective study using physical examination, pituitary function testing, computed tomography (CT), and histological examination at autopsy.
Animals or Sample Population — Eight laboratory beagle dogs.
Methods — Pituitary function was assessed before and at 10 weeks after hypophysectomy by combined administration of four releasing hormones (anterior pituitary), administration of haloperidol (pars intermedia), and infusion of hypertonic saline (posterior pituitary).
Results — CT imaging enabled accurate preoperative localization of the pituitary. Appropriate positioning and surgical technique facilitated exposure of the pituitary and its extraction without hemorrhage. Postoperative recovery was generally uncomplicated. None of die eight dogs had somatotropic, gonadotropic, lactotropic, melanotropic, or posterior pituitary responses to stimulation at 10 weeks after hypophysectomy. Four dogs (ACTH nonresponders) also had no cortico-tropic response and four (ACTH responders) had small but significant responses in the combined anterior pituitary function test. Adrenocortical atrophy was more pronounced in the ACTH nonresponders man in the responders. No residual pituitary tissue was found along the ventral hypothalamic diencephalon but nests of pituitary cells were found embedded in fibrous tissue in the sella turcica.
Conclusions — The surgical technique proved to be safe and effective. Microscopic nests of pituitary cells in the sella turcica may be responsible for residual corticotropic response to hypophysiotropic stimulation after hypophysectomy.
Clinical Relevance — The surgical technique may be used in the treatment of dogs with pituitary-dependent hyperadrenocorticism. The corticotropic response is the most sensitive criterion in assessing completeness of hypophysectomy in dogs.     

Dilated cardiomyopathy in an American Cocker Spaniel with taurine deficiency

An American Cocker Spaniel with low plasma taurine concentration (< 2 nmol/mL) was presented with dyspnoea associated with pulmonary oedema and a left ventricular shortening fraction of 9%. Emergency therapy with furosemide, dobutamine, nitroglycerine and oxygen supplementation led to a good response. Chronic therapy was started with enalapril, furosemide, digoxin and taurine. Improvement in all echocardiographic indices were noted over a 22 week follow-up, most notably an increase in left ventricular shorteningfraction to 20%, a decrease of E-point septal separation from 14 mm to 7 mm and marked left ventricular remodelling. This degree of improvement in myocardial function may represent a direct link between dilated cardiomyopathy in the American Cocker Spaniel andplasma taurine deficiency. Alternatively, this response may reflect a breed-related cardiomyopathy with a natural history and therapeutic response not commonly seen in the morecommon large breed cardiomyopathy presentations.