Blood chemistry and hematology of gray seal (Halichoerus grypus) pups from birth to postweaning.

Serum and plasma samples were collected from 92 gray seal (Halichoerus grypus) pups, all less than 5 wk old, and from 21 yearlings during the breeding season at the Isle of May, Firth of Forth, Scotland, for hematologic and clinical chemistry analysis. In the pups, total WBC, total protein, and glucose values increased until weaning and declined during the postweaning fast. Liver enzymes, particularly alkaline phosphatase, were high at birth and decreased steadily with age, most rapidly during the postweaning fast. In the yearlings, total WBC, erythrocyte sedimentation rates, and rectal temperatures were significantly higher than in the pups and glucose levels were significantly lower. Therefore, consideration should be given to the growth phase of gray seal pups (lactation or postweaning fast) or stage of development when hematology and clinical chemistries are used for diagnostic purposes.     

Affinity of detomidine, medetomidine and xylazine for alpha-2 adrenergic receptor subtypes

α₂-Adrenergic receptor agonists are widely used in veterinary medicine as sedative/hypnotic agents. Four pharmacological subtypes of the α₂-adrenergic receptor (A, B, C and D) have been identified based primarily on differences in affinity for several drugs. The purpose of this study was to examine the affinities of the sedative agents, xylazine, detomidine and medetomidine at the four α₂-adrenergic receptor subtypes. Saturation and inhibition binding curves were performed in membranes of tissues containing only one subtype of a₂-adrenergic receptor. The K_D for the α₂-adrenergic receptor radioligand, [³H]-MK-912, in HT29 cells (α_2A-), neonatal rat lung (α_2B-), OK cells (α_2C-) and PC12 cells transfected with RG20 (α_2D-) were 0.38 ± 0.08 n m , 0.70 ± 0.5 n m , 0.07 ± 0.02 n m and 0.87 ± 0.03 n m , respectively. Detomidine and medetomidine had approximately a 100 fold higher affinity for all the α₂-adrenergic receptors compared to xylazine but neither agonist displayed selectivity for the α₂-adrenergic receptor subtypes. These data suggest that available sedative/hypnotic α₂-adrenergic receptor agonists can not discriminate between the four known α₂-adrenergic receptor subtypes.     

Clinical natural history of the postsurgical cruciate deficient canine stifle joint: year 1

The aims of this prospective study were to investigate the associations and correlations between individual clinical features of osteoarthritis of the cruciate deficient stifle joint and to document the temporal changes in these features over a 13-month period following surgical treatment. Fifty-eight dogs with osteoarthritis of the stifle joint, secondary to cranial cruciate ligament deficiency, were examined before surgical treatment for cruciate deficiency and at one and a half, seven and 13 months after surgery. At each visit, clinical features were graded using four-point, discontinuous, ordinal grading (Likert) scales and intra-articular pathology was also scored in a similar fashion at arthrotomy. No attempt was made to construct an aggregate score because the relative importance of different disease features and the relationships between them were not understood at the time of writing. At entry, the relationships between background and disease variables and clinical parameters were investigated as well as the relationships between clinical parameters and intra-articular pathology scores. Longitudinal analysis was performed to test for those features which showed significant change over the 13-month follow-up period. At entry, periarticular thickening and degree of crepitus were significantly correlated with disease duration. Several features showed significant change over the study period. Notably, the degree of quadriceps atrophy showed significant decrease from baseline scores at seven and 13 months while remaining different from normal, suggesting that a measure of quadriceps atrophy may be a useful measure of long-term outcome in this disease.     

Holding Power of Different Pin Designs and Pin Insertion Methods in Avian Cortical Bone

Objective —To measure pullout strength of four pin types in avian humeri and tibiotarsi bones and to compare slow-speed power and hand insertion methods.
Study Design —Axial pin extraction was measured in vitro in avian bones.
Animal Population —Four cadaver red-tailed hawks and 12 live red-tailed hawks.
Methods —The pullout strength of four fixator pin designs was measured: smooth, negative profile threaded pins engaging one or two cortices and positive profile threaded pins. Part 1: Pins were placed in humeri and tibiotarsi after soft tissue removal. Part 2: Pins were placed in tibiotarsi in anesthetized hawks using slow-speed power or hand insertion.
Results —All threaded pins, regardless of pin design, had greater pullout strength than smooth pins in all parts of the study ( P < .0001). The cortices of tibiotarsi were thicker than the cortices of humeri ( P < .0001). There were few differences in pin pullout strengths between threaded pin types within or between bone groups. There were no differences between the pullout strength of pins placed by slow-speed power or by hand.
Conclusions —There is little advantage of one threaded pin type over another in avian humeri and tibiotarsi using currently available pin designs. There were few differences in pin pullout strengths between humeri and tibiotarsi bones. It is possible that the ease of hand insertion in thin cortices minimizes the potential for wobbling and therefore minimizes the difference between slow-speed drill and hand insertion methods.
Clinical Relevance —Threaded pins have superior bone holding strength in avian cortices and may be beneficial for use with external fixation devices in birds.     

A Comparison of Indirect Blood Pressure Monitoring Techniques in the Anesthetized Cat

Objective —To determine the accuracy of three indirect blood pressure monitoring techniques (oscillometric technique [OS], Doppler [DOP], and optical plethysmography [OP] [blood pressure determined with a pulse oximeter waveform]) when compared with direct arterial pressure measurement in cats. Study Design —Prospective study. Animal Population —Eight healthy (five female, three male), domestic short-hair cats, weighing 3.5 ± 0.8 kg Methods —Cats were anesthetized with isoflurane. The inspired concentration of isoflurane was adjusted to produce mild hypotension (80 to 100 mm Hg direct systolic), moderate hypotension (60 to 80 mm Hg direct systolic), and severe hypotension (<60 mm Hg direct systolic). Indirect pressure measurements were obtained from the thoracic limb and compared with concurrent direct measurement using regression analysis and a modification of Bland and Altman's technique. Results —All three techniques underestimated systolic pressure. OS produced the best prediction of systolic pressure with a bias ± precision of -15.9 ± 8.1 mm Hg. DOP and OP were relatively inaccurate with a bias ± precision of -25 ± 7.4 mm Hg and -25 ± 7.5 mm Hg. All three techniques correlated well with direct pressure with r values of 0.81, 0.88, and 0.88 for OS, DOP, and OP. DOP and OP provided an accurate prediction of direct mean arterial pressure with a bias ± precision of -0.8 ± 6 mm Hg and 0.6 ± 5.5 mm Hg. Correlation was good between DOP and mean arterial pressure with r = 0.89. Correlation was also good between OP and mean arterial pressure with r = 0.90. Conclusions —OS provided the most accurate prediction of direct systolic pressure. DOP and OP provided a good prediction of mean arterial pressure in the cat. Clinical Relevance —All three of these techniques are useful for detecting trends. Direct monitoring of blood pressure should be considered if accurate blood pressure measurement is required.