Aglepristone decreases proliferation in progesterone receptor-positive canine mammary carcinomas

Background: Progesterone receptor (PR) antagonist aglepristone (RU534) has been used successfully for pregnancy termination and therapy of pyometra, vaginal tumors, and mammary hyperplasia in bitches and queens. All of these conditions share with canine mammary carcinomas the expression of PR. Objectives: To study the effect of RU534 on proliferation and apoptosis in canine mammary carcinomas in relation to PR expression. Animals: Twenty‐seven nonspayed bitches with mammary carcinomas were treated with either 2 doses of 20 mg/kg RU534 (n = 22, RU534‐treated group) or oil placebo (n = 5, control group) on days 1 and 8. Methods: Tumor samples were collected before (day 1) and after (day 15) treatment for immunohistochemistry. PR expression, proliferation index (PI), and apoptotic index (AI) were determined using antibodies against PR, Ki67, and cleaved lamin A/C antigens, respectively. The effect of treatment on these parameters was analyzed. Results: Differential expression of PR between day 1 (59.1% PR‐positive tumors) and day 15 (36.4% PR‐positive tumors) was observed in RU534‐treated tumors exclusively. After RU534 treatment, mean PI was significantly decreased in PR‐positive but unchanged in PR‐negative RU534‐treated tumors. A reduction of ≥20% in PI was found in 61.5% of RU534‐treated tumors with PR expression. Conversely, no effect on AI was observed after RU534 treatment. Conclusions and Clinical Importance: Neoadjuvant RU534 treatment had PR expression‐related inhibiting effects on proliferation of canine mammary carcinoma cells.     

Pharmacokinetics of oxytetracycline in hemolymph from the Chinese mitten crab, Eriocheir sinensis

Feng, Q., Wu, G. H., Liang, T. M., Ji, H. Y., Jiang, X. J., Gu, W., Wang, W. Pharmacokinetics of oxytetracycline in hemolymph from the Chinese mitten crab, Eriocheir sinensis. J. vet. Pharmacol. Therap. 34 , 51–57. The purpose of this study was to investigate the hemolymph kinetics and depuration time of oxytetracycline following intramuscular administration at doses of 2, 8 and 40 mg/kg body weight, respectively. The concentration of OTC in hemolymph was assayed using solid phase extraction and high performance liquid chromatography. The elimination half‐life of the terminal part of the elimination phase (t_1/2β) ranged from 87.9 to 114.3 h. The total body clearance (CL_b) was 0.0430 L/kg/h at the lower dose, 0.0123 L/kg/h at the medium dose and 0.0013 L/kg/h at the higher dose. The apparent volume of the central compartment (V_c) was found to be 1.383, 0.699 and 0.143 L/kg respectively. The depuration time for each dose was 13.6, 29.6 and 57.6 days, respectively. Results from the present study suggest that the 40 mg/kg dose might have the best therapeutic efficacy following intramuscular administration.     

Comparison of the effects of etomidate and its fluoro analogue, R 8110, on plasma Cortisol, 11β-deoxycortisol, 17α-hydroxyprogesterone and testosterone concentrations in dogs

R 8110, an imidazole derivative, was shown to be clinically superior to etomidate for induction and maintenance of anaesthesia in dogs. The present study compared the effects of intravenous (i.v.) R 8110, etomidate and Ringer solution on cortisol biosynthesis by the adrenal gland in seven male labradors. A tetracosactide challenge was carried out 30 min after the i.v. injection of 3 mg/kg of both drugs and after i.v. Ringer solution (1 ml/kg). Etomidate and R 8110 both suppressed the cortisol response to tetracosactide almost completely and increased the plasma 11 beta-deoxycortisol levels more than 20 fold. Maximal 11 beta-deoxycortisol values were reached 120 min after R 8110, and not less than 300 min after etomidate. Plasma 17 alpha-hydroxyprogesterone and testosterone concentrations did not differ between placebo and R 8110 treatment, but they decreased after etomidate. These results indicate that the effects of R 8110 on steroid biosynthesis in dogs are less pronounced than those of etomidate and are largely limited to a temporary inhibition of the 11 beta-hydroxylase in the adrenal gland.     

Detection of leptospiral antigens in kidney and liver of cattle

This study was designed to investigate the presence of leptospiral antigens in kidney and liver of naturally infected cattle using an immunoperoxidase (IP) staining and Levaditi's staining methods. A total of 39 cattle suspected from leptospirosis were examined histologically and immunohistochemically for the presence of leptospiral antigens. The leptospiral antigens were detected in 16 out of 39 cases (seven kidneys, three livers, and six kidneys and livers) when IP staining method was used, whereas leptospiral antigens were detected in 6 out of 39 cases (four kidneys and two livers) when Levaditi's staining method was used. This study ascertained that IP staining was more sensitive method than Levaditi's staining method for demonstrating the presence of leptospirosis in cattle.     

Immunogenicity of infectious bursal disease viruses in chickens.

Cross-protective properties of infectious bursal disease viruses (IBDVs) were studied. Viruses represented different subtypes of serotype 1, including recently isolated viruses (variants), and a serotype 2 virus. Chickens were vaccinated at 3 weeks of age with inactivated vaccines containing 10(5), 10(6), 10(7), or 10(8) mean tissue-culture infectious dose of a given virus and challenged 2 weeks later using either 10(2) or 10(3.5) mean embryo infectious dose (EID50) of either a standard virus or a variant serotype 1 virus. Protection was evaluated at 5 and 10 days post-challenge, based on gross and microscopic lesions, body weight, and bursa/body-weight ratios. The serotype 2 virus did not confer protection on birds challenged with the serotype 1 viruses. Vaccines made of variant viruses at the low doses protected chickens challenged with the high or low doses of either the standard or the variant viruses. Vaccines made of the standard or variant strains at low doses protected against high or low challenge doses of the standard strain. Vaccines made of the high dose of any of the standard strains protected chickens against the variant virus when the low challenge dose (10(2) EID50) was used, but not when the high challenge dose (10(3.5) EID50) was used. The lowest dose of the standard viruses vaccines required to confer protection against the variant virus varied depending on the strain. Results indicated that protection depended on the strain and dose of both the vaccine and challenge viruses and that the variant strains and standard strains share a common protective antigen(s).     

Insulinoma in 2 guinea pigs (Cavia porcellus)

This paper describes an insulinoma in 2 guinea pigs (Cavia porcellus). Both guinea pigs presented with neurologic signs and low blood glucose readings. The neurologic signs resolved with dextrose administration. Insulinoma was confirmed on postmortem examination.     

Reproductive Disorders of Crossbred Dairy Cows in the Central Highlands of Ethiopia and Their Effect on Reproductive Performance

The study was conducted to estimate the proportion of reproductive disorders and to determine factors affecting reproductive performance of crossbred dairy cows under four different production systems in the central highlands of Ethiopia. The principal postpartum reproductive disorders were retained fetal membranes (14.7%) and uterine infection (15.5%). Anoestrus was the major postpartum reproductive problem in the mixed crop–livestock production system (38.6%) and was significantly associated with this production system. Apart from anoestrus, the occurrence of reproductive disorders was not significantly associated with a production system. Most of the reproductive disorders occurred as a complex rather than as a single abnormality. Two or more abnormal conditions were seen in 11.4% of the cases. Each reproductive trait measured was affected adversely by reproductive disorders. Cows with reproductive disorders in each production system, lactation group and suckling and non-suckling group had longer intervals from calving to first service and to conception (p < 0.001) and required more services per conception (p < 0.001). Pregnancy rate and conception to first service were 84.7% and 51.7%, respectively, for cows without reproductive health problems; and 64.2% and 15.1%, respectively, for cows with reproductive disorders (p < 0.001). Overall, intervals from calving to first service were shorter (p < 0.05) than in younger cows. Intervals from calving to first service and to conception were longer in suckling than in non-suckling cows (p > 0.05). Cows with a good body condition score (>3.5) at calving had shorter calving to first service and conception intervals than cows in poor condition (p < 0.001). The results showed that reproductive abnormalities, coupled with poor body condition, are important factors that contributed to reproductive inefficiency. An appropriate reproductive health management, a reliable artificial insemination service and supplementary feeding could be the management options to reduce or alleviate some of the problems.     

Subcutaneous Botryomycosis Due to Bibersteinia trehalosi in a Texas Longhorn Steer

A 3-year-old Texas Longhorn steer had a long history of progressive swelling of the soft tissues of the jaw and neck. At necropsy, multifocal to coalescing dermal and subcutaneous pyogranulomas were surrounded by fibrous tissue. Microscopically, the pyogranulomas contained aggregates of gram-negative coccobacilli surrounded by Splendore-Hoeppli material and were separated by bands of fibrovascular tissue (botryomycosis). Phylogenetic analysis of multilocus sequence-typing data revealed that the bacteria recovered in pure culture from swabs of submandibular tissue were most closely related to Bibersteinia [Pasteurella] trehalosi. The bacterial colonies were immunohistochemically reactive with a rabbit polyclonal anti-Pasteurella class C acid phosphatase antibody. Botryomycosis is a pyogranulomatous inflammation caused by a variety of nonbranching, nonfilamentous bacteria that elicit the formation of Splendore-Hoeppli material. This case of botryomycosis is unique for its association with Bibersteinia trehalosi.