Phenylbutazone in racing Greyhounds: plasma and urinary residues 24 and 48 hours after a single intravenous administration

SUMMARY The concentrations of phenylbutazone (PBZ), oxyphenbutazone (OPBZ) and gammahydroxyphenylbutazone (OHPBZ) in plasma and urine from 50 Greyhounds 24 and 48 h after the intravenous administration of a single dose of PBZ (30 mg/kg) were measured. The 24 h plasma concentrations of OPBZ and OHPBZ, the 48 h plasma concentration of OHPBZ and the 24 h urinary concentration of PBZ were normally distributed, while log transformations were required before the 24 h plasma concentration of PBZ and the 24 and 48 h urinary concentrations of OPBZ and OHPBZ became normally distributed. The 95%, 99%, 99.9% and 99.99% upper predicted confidence intervals for both 24 h and 48 h plasma and urinary concentrations demonstrated wide potential variation in the concentration of the analytes should PBZ be administered to Greyhounds. The 24 h plasma and urinary concentrations of PBZ were weakly correlated, but no similar relationship existed for OPBZ or OHPBZ. The urinary concentrations of each analyte were not affected by the trainer or sex of the Greyhound or the urinary pH. We conclude that it would be impossible to predict the timing of the PBZ administration or the plasma concentration of PBZ from the measurement of the concentration of PBZ in a single sample of urine.     

Carbon structures with three-dimensional periodicity at optical wavelengths

Porous carbons that are three-dimensionally periodic on the scale of optical wavelengths were made by a synthesis route resembling the geological formation of natural opal. Porous silica opal crystals were sintered to form an intersphere interface through which the silica was removed after infiltration with carbon or a carbon precursor. The resulting porous carbons had different structures depending on synthesis conditions. Both diamond and glassy carbon inverse opals resulted from volume filling. Graphite inverse opals, comprising 40-angstrom-thick layers of graphite sheets tiled on spherical surfaces, were produced by surface templating. The carbon inverse opals provide examples of both dielectric and metallic optical photonic crystals. They strongly diffract light and may provide a route toward photonic band-gap materials.     

Treatment of anovulatory anoestrous postpartum dairy cows with a gonadotropin-releasing hormone (GnRH), prostaglandin F2𝛂, GnRH regimen or with progesterone and oestradiol benzoate

AIM: To compare 2 treatments for anovulatory anoestrus (AA) in postpartum dairy cows. The treatments were combinations of gonadotropin-releasing hormone (GnRH) and prostaglandin F_2𝛂 (PG) or progesterone (P4) and oestradiol benzoate (ODB).

METHODS: Forty AA cows from each of 5 herds were blocked by age (2 or >2 years old) and randomly assigned to 1 of 2 treatments. The first group (GPG) were treated with 250 𝛍g of a GnRH analogue, gonadorelin, followed 7 days later by 15 mg of the PG analogue, luprostiol. Two days later the cows were injected with 250 𝛍g of gonadorelin. Cows were artificially inseminated 16–24 h after the second GnRH injection. The second group (P4+ODB) were treated with an intravaginal P4 releasing device for 6 days, followed 24 h after device removal by injection of 1 mg of ODB. Cows were pregnancy tested 35–40 days after the initial insemination and twice again at 6–8 week intervals thereafter.

RESULTS: There was no significant difference between P4+ODB and GPG groups in the percentage of cows submitted for insemination in the first 7 days (94.0% vs 100% for P4+ODB vs GPG, respectively; p>0.3), in conception rate to first insemination within the first 7 days (43.6% vs 35.0% for P4+ODB vs GPG, respectively; p>0.2), in the percentage of cows conceiving in the first 28 days of the breeding period (68.0% vs 58.3%, P4+ODB vs GPG, respectively; p>0.1), or in median interval from the end of treatment to conception (20 vs 21days;p>0.1).

CONCLUSIONS: No differences in the reproductive performance of AA cows treated with either P4+ODB or GPG were detected. However, given the small number of animals enrolled, further data are required before the GPG protocol can be recommended for treatment of AA cows.     

Effect of Ascorbic Acid Concentrations,Methods of Cooling and Freezing on Boer Goat Semen Cryopreservation

To improve the Boer goat semen quality during cryopreservation process, three experiments were carried out to investigate the effect of (i) different concentration of ascorbic acid supplementation (ii) rate of cooling with chilled semen characteristics and (iii) method of freezing on post‐thaw Boer goat sperm using Tris‐based extender. Ascorbic acid at 8.5 mg/ml improved the sperm parameters (motility, integrity of membrane and acrosome, morphology and viability), compared to control in cooled samples (p < 0.05). With regard to other concentrations and post‐thawed parameters, ascorbic acid at 2.5–8.5 mg/ml led to higher percentages of sperm motility and integrities of membrane and acrosome when compared to control (p < 0.05). Slow cooling rises to higher percentages of sperm motility, acrosome integrity and viability, in comparison with fast cooling, in terms of cooled and frozen samples (p < 0.05). Programmable freezing method produced the higher percentages of sperm motility, integrities of membrane and acrosome and viability when compared to the freezing method of polystyrene box during goat sperm freezing (p < 0.05). In conclusion, chilled and post‐thawed sperm quality of Boer goat was improved when a Tris‐based extender supplemented with ascorbic acid was used at stages of different cooling rates and freezing methods.     

Pre‐ and Post‐Partum Mild Underfeeding Influences Gene Expression in the Reproductive Tract of Cyclic Dairy Cows

Undernutrition before and after calving has a detrimental effect on the fertility of dairy cows. The effect of nutritional stress was previously reported to influence gene expression in key tissues for metabolic health and reproduction such as the liver and the genital tract early after calving, but not at breeding, that is, between 70 and 90 days post‐partum. This study investigated the effects of pre‐ and post‐partum mild underfeeding on global gene expression in the oviduct, endometrium and corpus luteum of eight multiparous Holstein cows during the early and middle phases of an induced cycle 80 days post‐partum. Four control cows received 100% of energy and protein requirements during the dry period and after calving, while four underfed received 80% of control diet. Oestrous synchronization treatment was used to induce ovulation on D80 post‐partum. Oviducts, ovaries and the anterior part of each uterine horn were recovered surgically 4, 8, 12 and 15 days after ovulation. Corpora lutea were dissected from the ovaries, and the endometrium was separated from the stroma and myometrium in each uterine horn. The oviduct segments were comprised of ampulla and isthmus. RNAs from ipsi‐ and contralateral samples were pooled on an equal weight basis. In each tissue, gene expression was assessed on a custom bovine 10K array. No differentially expressed gene (DEG) in the corpus luteum was identified between underfed and control, conversely to 293 DEGs in the oviduct vs 1 in the endometrium under a false discovery rate (FDR) < 0.10 and 1370 DEGs vs 3, respectively, under FDR < 0.15. Additionally, we used dedicated statistics (regularized canonical correlation analysis) to correlate the post‐partum patterns of six plasma metabolites and hormones related to energy metabolism measured weekly between calving and D80 with gene expression. High correlations were observed between post‐partum patterns of IGF‐1, insulin, β‐hydroxybutyrate and the expression in the oviduct of genes related to reproductive system disease, connective tissue disorders and metabolic disease. Moreover, we found special interest in the literature to retinoic acid‐related genes (e.g. FABP5/CRABP2) that might indicate abnormalities in post‐partum tissue repair mechanisms. In conclusion, this experiment highlights relationships between underfeeding and gene expression in the oviduct and endometrium after ovulation in cyclic Holstein cows. This might help to explain the effect of mild undernutrition on fertilization failure and early embryonic mortality in post‐partum dairy cows.     

Wounds of the pastern and foot region managed with phalangeal casts: 50 cases in 49 horses (1995–2006)

Objective   Describe the use of a phalangeal cast as treatment for wounds in the pastern and foot region of horses. Secondly, to evaluate the healing and soundness of horses treated with phalangeal casts.
Design   Retrospective study of 49 horses.
Procedures   Medical records of 49 horses that were treated with a phalangeal cast for 50 cases of wounds in the pastern and foot region at equine referral hospitals from 1995 to 2006 were reviewed and follow-up information was obtained.
Results   Treatment consisted of wound debridement, lavage, wound closure (28 wounds), cast application and antibiotics (84%). At follow-up, the majority of horses were sound (42 of 47 wounds, 89.4%), three horses were still lame and one horse was euthanased because of persistent lameness. Three horses were lost to follow-up. There was no statistical difference between the outcomes of horses treated acutely (<24 h) or after a 24-h delay. Similarly, the involvement of synovial structures in the wound did not significantly influence outcome.
Conclusions   In this study, wounds involving the pastern and foot that were treated with a phalangeal cast carried a good prognosis for soundness (89.4%) and cosmetic healing (89.5%). The phalangeal casts were well-tolerated and effective.     

Sensitivity and specificity of western blot testing of cerebrospinal fluid and serum for diagnosis of equine protozoal myeloencephalitis in horses with and without neurologic abnormalities

OBJECTIVE: To determine sensitivity and specificity of western blot testing (WBT) of CSF and serum for diagnosis of equine protozoal myeloencephalitis (EPM) in horses with and without neurologic abnormalities. DESIGN: Prospective investigation. ANIMALS: 65 horses with and 169 horses without neurologic abnormalities. PROCEDURE: CSF and serum from horses submitted for necropsy were tested for Sarcocystis neurona-specific antibody with a WBT. Results of postmortem examination were used as the gold standard against which results of the WBT were compared. RESULTS: Sensitivity of WBT of CSF was 87% for horses with and 88% for horses without neurologic abnormalities. Specificity of WBT of CSF was 44% for horses with and 60% for horses without neurologic abnormalities. Regardless of whether horses did or did not have neurologic abnormalities, sensitivity and specificity of WBT of serum were not significantly different from values for WBT of CSF. Ninety-four horses without EPM had histologic evidence of slight CNS inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: The low specificity of WBT of CSF indicated that it is inappropriate to diagnose EPM on the basis of a positive test result alone because of the possibility of false-positive test results. The high sensitivity, however, means that a negative result is useful in ruling out EPM. There was no advantage in testing CSF versus serum in horses without neurologic abnormalities. Slight CNS inflammation was common in horses with and without S neurona-specific antibodies in the CSF and should not be considered an indication of CNS infection with S neurona.     

Enzyme-linked immunosorbent assay for the detection of antibodies to bovine viral diarrhea virus in bovine sera

A specific and sensitive enzyme-linked immunosorbent assay (ELISA) was established for the detection of antibodies to bovine viral diarrhea virus (BVDV) in bovine sera. Polyethylene-glycol concentrated, equilibrium density gradient purified BVDV was used as test antigen at an optimal amount of 1 microgram/well, whereas the optimal concentration of conjugate was at 1/2000 dilution. The standardized test encountered no non-specific reaction with test sera at a starting dilution of 1/10. A total of 50 bovine serum samples was assayed for the presence of antibodies against BVDV by ELISA and serum neutralization test (SNT). A positive correlation between the 2 tests was found. However, ELISA could be as much as 500-fold more sensitive than SNT in detecting low levels of BVDV antibodies.     

Nonspecific reactions in an enzyme-linked immunosorbent assay caused by binding of immunoglobulins in situ to egg-propagated infectious bronchitis virus

High levels of nonspecific background absorbance and increased variability were found in a previously optimized enzyme-linked immunosorbent assay (ELISA) for infectious bronchitis virus (IBV) antibody after changing to commercially available non-pathogen-free eggs for viral antigen production. An increase in bound viral antigen in the assay caused a proportionate increase in the nonspecific binding of the conjugate, independent of other variables, in the absence of serum. Virus was propagated in non-pathogen-free eggs, and individual viral proteins were separated by polyacrylamide gel electrophoresis and transferred to nitrocellulose. Localization of chicken IgG-virus complexes were identified by immunoprecipitation with peroxidase-conjugated anti-chicken IgG. Specific staining at molecular weights corresponding to major proteins of IBV was demonstrated in these viral preparations. Virus grown in specific-pathogen-free eggs and treated in the same manner showed only slight amounts of staining. This evidence suggests that viral antigens grown in eggs from a non-pathogen-free flock bind with maternal chicken immunoglobulins present in the allantoic cavity of eggs. This IgG caused nonspecific reactions in our chicken ELISA system and gives cause for concern in any diagnostic system requiring the propagation of agents in fertile eggs.