Clinical pathology of amphibians: a review

Amphibian declines and extinctions have worsened in the last 2 decades. Partly because one of the main causes of the declines is infectious disease, veterinary professionals have increasingly become involved in amphibian research, captive husbandry, and management. Health evaluation of amphibians, free‐living or captive, can benefit from employing the tools of clinical pathology, something that is commonly used in veterinary medicine of other vertebrates. The present review compiles what is known of amphibian clinical pathology emphasizing knowledge that may assist with the interpretation of laboratory results, provides diagnostic recommendations for common amphibian diseases, and includes RIs for a few amphibian species estimated based on peer‐reviewed studies. We hope to encourage the incorporation of clinical pathology in amphibian practice and research, and to highlight the importance of applying veterinary medicine principles in furthering our knowledge of amphibian pathophysiology.     

Pyrenocines J-M: four new pyrenocines from the endophytic fungus, Phomopsis sp

Four new pyrenocines, named pyrenocines J-M (1-4), were isolated from an endophytic fungus, Phomopsis sp, by a bioassay-guided method. The structures of the new compound have been assigned from 1H and 13C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. Preliminary studied showed that compounds 1, 2 and 4 showed good antifungal, antibacterial, and algicidal properties, while compound 3 had good antibacterial and algicidal properties.     

The effects of succinylcholine or low-dose rocuronium to aid endotracheal intubation of adult sows

This randomized, prospective, blinded study compared the use of succinylcholine or rocuronium to aid endotracheal intubation of 27 adult sows [mean body weight 261 ± 28 (standard deviation) kg]. Preliminary trials allowed development of the intubation technique and skills. The sows were premedicated with azaperone, atropine, and morphine, and anesthesia was induced with thiopental [6 mg/kg body weight (BW)]. Nine sows each received succinylcholine (1.0 mg/kg BW), rocuronium (0.5 mg/kg BW), or saline (15 mL) after induction. Increments of thiopental (1 mg/kg BW) were used if swallowing impaired intubation. Intubation was performed 45 s after injection of the test drug and was timed and scored. The intubation scores were analyzed with Kruskal-Wallis analysis of variance (ANOVA). Time taken for intubation, body weight, and total dose of thiopental were analyzed with ANOVA and Bonferroni's multiple-comparisons test. No significant differences (at P < 0.05) were found between the groups with regard to intubation score, time taken for intubation, or total thiopental dose. Thus, neuromuscular blocking agents did not aid endotracheal intubation of adult sows anesthetized with thiopental.     

Resistance to classical scrapie in experimentally challenged goats carrying mutation K222 of the prion protein gene

ABSTRACT: Susceptibility of sheep to scrapie, a transmissible spongiform encephalopathy of small ruminants, is strongly influenced by polymorphisms of the prion protein gene (PRNP). Breeding programs have been implemented to increase scrapie resistance in sheep populations; though desirable, a similar approach has not yet been applied in goats. European studies have now suggested that several polymorphisms can modulate scrapie susceptibility in goats: in particular, PRNP variant K222 has been associated with resistance in case-control studies in Italy, France and Greece. In this study we investigated the resistance conferred by this variant using a natural Italian goat scrapie isolate to intracerebrally challenge five goats carrying genotype Q/Q 222 (wild type) and five goats carrying genotype Q/K 222. By the end of the study, all five Q/Q 222 goats had died of scrapie after a mean incubation period of 19 months; one of the five Q/K 222 goats died after 24 months, while the other four were alive and apparently healthy up to the end of the study at 4.5 years post-challenge. All five of these animals were found to be scrapie negative. Statistical analysis showed that the probability of survival of the Q/K 222 goats versus the Q/Q 222 goats was significantly higher (p = 0.002). Our study shows that PRNP gene mutation K222 is strongly associated with resistance to classical scrapie also in experimental conditions, making it a potentially positive target for selection in the frame of breeding programs for resistance to classical scrapie in goats.     

Immunophenotyping and characterization of BNP colostra revealed pathogenic alloantibodies of IgG1 subclass with specifity to platelets, granulocytes and monocytes of all maturation stages

Bovine neonatal pancytopenia (BNP) is mainly characterized by multiple haemorrhages, thrombocytopenia and leukocytopenia as a result of bone marrow depletion. BNP can be induced in healthy calves through application of colostrum from BNP donors, proofing that BNP is mediated to maternal alloantibodies. Alloantibody binding to bovine blood cells is present in sera and colostra of BNP donors and is probably initialized by vaccination with a certain BVD vaccine. To understand etiology and pathomechanisms of BNP, we closely characterized disease inducing antibodies regarding immunoglobulin subclass and binding specificities to peripheral blood derived leukocytes and platelets. By exact phenotyping the targeted blood cell subsets, including platelets for the first time, we investigated that BNP alloantibodies are exclusively of IgG1 subclass. Interestingly, IgG1 of BNP colostra bound to 70% leukocytes and 100% platelets irrespective of different bovine breeds and cellular maturity of all specimens tested. Furthermore, staining pattern on platelets as well as leukocyte subsets by BNP-IgG1 alloantibody exposed 100% reactivity to platelets, granulocytes and monocytes. Interestingly, the main part of T-helper cells was not bound by colostral alloantibodies. Our results point to a crucial role of IgG1 antibodies in BNP and to a target antigen that is expressed by all cells of myeloid lineage, but only partially by the lymphoid lineage.     

Could fetal fluid and membranes be an alternative source for Mesenchymal Stem Cells (MSCs) in the feline species? A preliminary study

Domestic cats are preferred models for normal physiology and several human diseases. In the present study feline fetal fluids and membranes were evaluated as possible sources of MSCs. Samples were recovered from 4 pregnant queens after ovarian-hysterectomy. Gestational sacs were separated from uterine wall; after allantoic and amniotic fluids aspiration and chorion-allantois and amniotic membranes separation, all cell lineages were cultured into 25 cm(2) flasks, in DMEM/TCM199, in a 5% CO(2) incubator at 38.5 °C. At passage 3, chondrogenic, osteogenic and adipogenic differentiation ability were evaluated by culturing cell monolayers in differentiating media for 21 days. Cellular characterization with CD90, CD44, CD105, CD73, CD34, CD14, CD45, was performed by flow cytometry. In all samples, adherent fibroblastoid spindle-shaped cells were observed. Positive von Kossa and Alizarin Red staining confirmed osteogenesis. Alcian blue staining of matrix glycosaminoglycans illustrated chondrogenesis, and positive Oil Red O lipid droplets within cell cytoplasm suggested adipogenesis. All cell lines isolated were positive for CD90, CD44, CD105 and negative for CD34, CD14 and CD45; as unexpected and different from human cells, feline cells resulted negative for CD73. Based on this preliminary results, fetal fluids and membranes could represent an alternative sources for mesenchymal stem cells in feline species.     

Hind limb kinematics during therapeutic exercises in dogs with osteoarthritis of the hip joints

Objective-To assess joint kinematics in dogs with osteoarthritis of the hip joints during walking up an incline or down a decline and over low obstacles and to compare findings with data for nonlame dogs. Animals-10 dogs with osteoarthritis of the hip joints (mean ± SD age, 6.95 ± 3.17 years; mean body weight, 34.33 ± 13.58 kg) and 8 nonlame dogs (3.4 ± 2.0 years; 23.6 ± 4.6 kg). Procedures-Reflective markers located on the limbs and high-speed cameras were used to record joint kinematics during walking up an incline or down a decline and over low obstacles. Maximal flexion, extension, and range of motion of the hip joints were calculated. Results-Osteoarthritis of the hip joints reduced extension of both hip joints and flexion of the contralateral hind limb, compared with flexion of the lame hind limb, during walking down a decline. Walking up an incline resulted in decreased extension of the stifle joint in both hind limbs of osteoarthritic dogs; extension was significantly decreased for the lame hind limb. During walking over low obstacles, maximal flexion of the stifle joint was increased significantly for the contralateral hind limb. Maximal flexion was increased in both tarsal joints. Conclusions and Clinical Relevance-Osteoarthritis of the hip joints led to complex changes in the gait of dogs, which involved more joints than the affected hip joint alone. Each exercise had specific effects on joint kinematics that must be considered when planning a rehabilitation program.