Multidose pharmacokinetics of orally administered florfenicol in the channel catfish (Ictalurus punctatus)

Plasma disposition of florfenicol in channel catfish was investigated after an oral multidose (10 mg/kg for 10 days) administration in freshwater at water temperatures ranging from 24.7 to 25.9 °C. Florfenicol concentrations in plasma were analyzed by means of liquid chromatography with MS/MS detection. After the administration of florfenicol, the mean terminal half‐life (t_1/2), maximum concentration at steady‐state (C_ss(max)), time of C_ss(max) (T_max), minimal concentration at steady‐state (C_ss(min)), and V_c/F were 9.0 h, 9.72 μg/mL, 8 h, 2.53 μg/mL, and 0.653 L/kg, respectively. These results suggest that florfenicol administered orally at 10 mg/kg body weight for 10 days could be expected to control catfish bacterial pathogens inhibited in vitro by a minimal inhibitory concentration value of <2.5 μg/mL.     

Sonographic characteristics of goat testis on water bath based ultrasonography

Assessing the health of the testes in domestic animals is an important aspect of the breeding soundness examination and selection. The aim of the present study was to develop a simple method for scanning and to establish ultrasonographically the gross anatomic structures of the goat testes. Six adult male goats were examined to study the sonographic appearance of normal testes and epididymides using a water bath based ultrasound scanning technique. The ultrasonographic examinations were done using a 5–9 MHz/60 mm (7.5 MHz) linear-array transducer and a B-mode scanner. The ultrasonographic examination was performed in goats after standardizing the procedure on six testes collected from slaughter house. Results showed that in live goats when the probe was placed directly over the scrotum it gave distorted and unclear image. In water bath method the entire scrotum was dipped into a container filled with water and linear probe was used to observe the sonographic features of the testis. Each testis was viewed vertically, resulting in longitudinal image which was frozen, measured and printed through a thermal printer. The results of the ultrasonogram revealed that the testicular parenchyma was homogenous and moderately echogenic throughout. The diameter (mean±se) of the right and left testes was 4.47±0.14 and 4.42±0.07 cm respectively and no significant difference was observed between the testes. The mediastinum testis was a 1.50±0.22 cm wide linear structure of greater echogenicity than the testicular parenchyma when viewed in the transverse plane and nearly circular echogenic “spot” in the midline of the testis when viewed horizontally. The head and tail of the epididymides were easily identified on all the testes, but the epididymal body and ductus deferens were difficult to identify consistently. The tail of the epididymis was easily identified on the distal end of the testis with sonolucent tubules and appeared sonographically as a ‘peaked cap’ upon the testicular parenchyma. The diameter (mean±se) of the tail of right and left epididymis was 2.11±0.18 and 1.92±0.06 cm and no significant difference was observed between epididymides. The vascular pampiniform plexus (1.42±0.18 cm) was easily identified on the proximal end of the testes. The tunics of the testes appeared as a bright echogenic line. Inter-testicular septum appeared between testes as a hyperechoic line. It is concluded that ultrasonography permits a noninvasive evaluation of the internal structure of the scrotum and testes and water bath based sonographic examination may prove to be a valuable simple diagnostic methodology for evaluating physiopathologic conditions of goat testes and can be employed as a routine investigative method during breeding soundness and clinical examination.     

Ovarian Structure and Oogenesis of Catfish Pimelodella vittata (Lütken, 1874) (Siluriformes,Heptapteridae)

The morphology of the ovaries and oogenesis of Pimelodella vittata were studied using anatomical and histological techniques to provide information of its reproductive biology. Eighty adult females were captured trimonthly during the period November 2005 to October 2006. The ovaries are paired, saculiform organs, which are coated with tunica albuginea and contain ovigerous lamellae, where the oocytes develop before being released into the ovarian lumen and following the ovarian duct until reaching the genital papilla. Oogenesis was divided into stages based on the alterations to the nucleus, ooplasm and surrounding follicular layers. Oogonia form groups from the germinal epithelium have asynchronous development and differentiate into initial perinucleolar oocytes. The formation of the zona pellucida is initiated in the advanced perinucleolar oocytes reaching a thickness of 1.46 ± 0.58 μm in the vitellogenic oocytes. The follicular cells are squamous in perinucleolar oocytes, become cubical in the pre‐vitellogenic oocytes and prismatic in the vitellogenic oocytes with a height of 11.20 ± 4.74 μm. The histochemical reactions indicate that zona pellucida, cortical alveoli and yolk globules contain neutral glycoproteins and the follicular cells contain neutral glycoproteins in association with carboxylated and sulphated glycoconjugates. Statistical analyses showed significant differences in the diameter of the oocytes and follicular cells height as oocytes matured. This study represents the first data about the ovarian structure and oogenesis of this species.     

The Histological Appearance of the Proximal Aspect of the Dorsal Condylar Sagittal Ridge of the Third Metacarpal and Metatarsal Bone in Young Warmblood Horses: Normal Appearance and Correlation with Detected Radiographic Variations

The objective of this study is to describe the normal histological appearance of the dorsoproximal aspect of the sagittal ridge of the third metacarpal/metatarsal bone in young Warmblood horses, and to compare it to the different radiographic variations (irregular, indentation, lucency, notch) described at this level. A total of 25 metacarpo/metatarsophalangeal joints of 12 Warmblood horses were used. Five samples of each radiographically described group were selected for histological processing. Each category was compared with the normal control group. Each group showed a bone cortex, covered by hyaline cartilage and longitudinally aligned collagen fibres covered by loosely organized connective tissue proximally. The normal and irregular group showed a smooth bone cortex. In the indentation and lucency group, a depression in the cortex was detected. The notch group presented an expansion of the cortex. The collagen fibres and connective tissue were located in the depression in the indentation group whereas the location varied in the lucency and notch group. The radiologic detected differences are translated into detectable histological differences. Further research is warranted to determine whether these variations are developmental or congenital and to evaluate their potential influence on the joint function during hyperextension.     

Laser treatment of urethral defects in geldings and stallions used as the primary treatment or in combination with a temporary subischial incision: Eight cases (2003–2011)

Two geldings with haematuria and 6 stallions with haemospermia presented for evaluation between 2003 and 2011 to the Iowa State University Lloyd Veterinary Medical Center. Both geldings presented for haemorrhage at the end of urination. All stallions presented for evaluation of infertility following natural service or artificial insemination that was related to haemospermia. Urethroscopy identified a urethral defect in all 8 horses. Both geldings possessed a urethral rent. One stallion possessed a urethral varicosity while the remaining 5 possessed a urethral rent. Two geldings and 2 stallions received only laser treatment. The remaining 4 stallions received concurrent laser treatment with a temporary subischial incision (TSI) into the corpus spongiosum penis. All 6 stallions received 8 weeks of sexual rest after the completion of the surgical/laser treatment. Laser treatment alone was successful in resolving haematuria in one of 2 geldings. In the stallion group, all 4 horses with a urethral rent receiving laser treatment concurrent with a TSI resolved haemospermia. Of the remaining stallions, one with a urethral varicosity resolved clinical signs with only laser treatment and one stallion with a urethral rent received only laser treatment and haemospermia recurred. We conclude that laser treatment of a urethral rent in geldings can result in resolution of haematuria. Laser treatment used in combination with a TSI may result in improved success when compared to surgery alone. Laser treatment alone can result in resolution of a urethral varicosity.     

Duplex gall bladder associated with choledocholithiasis, cholecystitis, gall bladder rupture and septic peritonitis in a cat

A 10-year-old cat was presented with a history of inappetence, pyrexia and weight loss. Clinical investigations showed anaemia, hyperbilirubinaemia, septic peritonitis and a double gall bladder with choleliths in an extrahepatic duct. Initial medical stabilisation was performed. At laparotomy, a duplex gall bladder with two separate cystic ducts was identified. The left gall bladder was thickened and had ruptured at the apex. Multiple choleliths were identified in the left cystic duct. The right gall bladder and cystic duct were grossly normal. The ruptured gall bladder was repaired, the gallstones were removed via a choledochotomy of the left cystic duct and a choledochoduodenostomy was created from the dilated left cystic duct. The cat remained depressed and anorexic, and it was euthanased 72 hours postoperatively at the owners' request. This is the first ante-mortem investigation of extrahepatic biliary disease associated with gall bladder duplication in the cat.