Characterization of changes related to mineral balance and bone metabolism in the young racing Quarter Horse

This study was conducted to determine physiologic responses reflective of bone metabolism during the onset of training and to relate those responses to the mineral requirements of young racehorses. Ten previously untrained Quarter Horse geldings were put into race training. They were fed a diet balanced to meet NRC recommendations for young horses in training. Feed, feces and urine were collected, weighed and analyzed over the experiment to determine mineral balance. Radiographs were taken of the left front leg to determine mineral content of a cross-sectional area of the third metacarpal. Blood samples were taken to determine osteocalcin, parathyroid hormone, 25-hydroxyvitamin D, Ca and inorganic P concentrations. Horses were gentled to ride, trained to gallop on the track and maintained in training for four 28-day periods. Blood serum was collected every 14 day, while radiographs and 72-hr total collections of urine and feces were taken every 28 d. Radiographs demonstrated that mineral content was lowest at day 56 in the dorsal, palmar and medial cortices of the third metacarpal. Urinary Ca declined dramatically from day 0 to day 28, then remained constant to day 56, before decreasing at day 84. Fecal Ca peaked at day 28 and remained elevated above day 0 amounts until day 112. calcium retention was negative at day 0, became slightly positive by day 28 and increased through day 112. Phosphorus and Mg balance remained relatively unchanged throughout the duration of the study. This study demon-strated changes in the mineral content of the third metacarpal and Ca balance during early training and suggests that further studies be performed.     

Pathogenesis of porcine Actinobacillus pleuropneumonia, part II: roles of proinflammatory cytokines.

The in vitro production of proinflammatory cytokines after stimulation with Actinobacillus pleuropneumoniae and the relation of these cytokines in vivo with the disease caused by A. pleuropneumoniae were investigated. Within 24 h, in vitro stimulation by A. pleuropneumoniae (serotype 1) preparations, including killed bacteria, bacterial culture supernatant, lipopolysaccharide, and bacterial extracts, porcine pulmonary alveolar macrophages (PAM) produced significant (P < 0.05) amounts of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) as measured by bioassays. The supernatants containing interleukin-8 from PAM after stimulation by bacterial preparations showed significant neutrophil chemotaxis, while bacterial preparations alone did not. After in vivo infection with A. pleuropneumoniae, the mean levels of TNF-alpha and IL-1 in serum, as measured by bioassays, were elevated 37- to 27836-fold for TNF-alpha and 11- to 5941-fold higher for IL-1 within 4 d post-infection, depending on the treatments, and remained elevated up to Day 7. Both cytokines were also detected in porcine lungs by bioassays and immunocytochemistry. The results indicated that both secreted and surface components of A. pleuropneumoniae can stimulate PAM to produce proinflammatory mediators. Neutrophil chemoattractants rather than bacterial components are the major factor causing acute lung inflammation. The elevation of TNF-alpha and IL-1 in pigs occurred coincident with the onset of acute clinical disease.     

Mitoxantrone and cyclophosphamide combination chemotherapy for the treatment of various canine malignancies.

Thirteen dogs with histopathologically confirmed malignancies were treated with mitoxantrone and cyclophosphamide combination therapy. One to four doses were administered at 21-day intervals. Recombinant human granulocyte colony-stimulating factor was administered to ameliorate myelosuppression in dogs with neutrophil nadirs less than 1,000/microl. While the protocol appears to be safe for use in tumor-bearing dogs, an advantage over mitoxantrone single-agent protocols in terms of tumor response was not demonstrated in this initial pilot study.     

Potential impact of weedy Brassicaceae species on oil and meal quality of oilseed rape (canola) in Australia

Brassicaceae weeds are a widespread problem in Australian oilseed rape crops. The weeds not only compete for resources during crop growth, but also have the potential to reduce both oil and meal quality of the harvested crop. This study investigated oil and meal quality of weedy species from the Brassicaceae family that were collected throughout cropping regions of Australia. Eighty‐nine lines from 19 species were grown and evaluated in the same environment for their potential to contaminate Australian oilseed rape seed lots. Seed and flowering characteristics of each species were also examined. The glucosinolate concentration of most of the weedy species was greater than 100 μmol g^?1 of oil‐free meal, well above the threshold for meeting oilseed rape quality. Erucic acid content of 18 of the 19 weedy species also exceeded the oilseed rape quality standard of less than 2% erucic acid. This study highlights the potential of the weedy species to reduce the quality of Australian oilseed rape crops.     

What is your diagnosis? Vertebral mass in a dog

Abstract: A 1‐year‐old, castrated male, mixed‐breed dog was presented for sporadic episodes of kyphosis, tremors, and vocalizing. On neurologic examination, the lesion was localized to spinal cord segments T3–L3. Magnetic resonance imaging of the spine showed an expansile mass occupying most of the ventral aspect of the spinous process of T6. Fine‐needle aspirates of the mass were examined cytologically. A moderately cellular population of pleomorphic spindle cells and abundant mucinous matrix were observed. The cytologic diagnosis was spindle cell neoplasia, with myxosarcoma and fibrosarcoma as the primary differential diagnoses. The dog was euthanized. Histopathologic evaluation of the mass and surrounding tissue confirmed a low‐grade spindle cell sarcoma, with severe compressive myelopathy and mild neutrophilic inflammation. The neoplastic cells stained positive for mucopolysaccharides with Alcian blue, resulting in a final diagnosis of low‐grade (grade 1) myxosarcoma. Fine‐needle aspiration was useful in making a preliminary diagnosis of myxosarcoma in this case. Myxosarcoma should be included in the differential diagnosis for a vertebral mass in a young dog.     

Evaluation of chlorfenapyr for control of the bed bug,Cimex lectularius L.

BACKGROUND: The presence of bed bug populations resistant to pyrethroids demands the development of new control tactics, including the use of insecticides with new modes of action. Insecticides that disrupt oxidative phosphorylation in insect mitochondria can be an option. Laboratory assays were used to measure the toxicity of chlorfenapyr to susceptible strains and two strains highly resistant to pyrethroids. The effectiveness of two chlorfenapyr‐based formulations was compared, and behavioral responses of bed bugs to dry residues of aerosol sprays were evaluated. RESULTS: Chlorfenapyr was effective against all bed bug strains, killing them at a similar rate, regardless of their susceptibility status to pyrethroids. Dry residues aged for 4 months were as toxic as fresh dry residues. The aerosol formulation had contact activity and caused faster mortality than a water‐based formulation. Bed bugs did not avoid resting on surfaces treated with aerosol. CONCLUSION: Chlorfenapyr is an option for controlling pyrethroid‐resistant bed bugs. While it does not cause quick knockdown, its long residual activity and no avoidance behavior of bed bugs to dry residues appear to make this insecticide suitable for bed bug control. A faster insecticidal effect is obtained with the aerosol formulation, suggesting greater bioavailablity of the toxicant. Copyright © 2010 Society of Chemical Industry     

All three classes of CpG ODNs up-regulate IP-10 gene in pigs

The analysis of CpG ODN induced innate immune responses in different animal species has shown substantial similarities and differences in levels and types of induced cytokines profile. The objectives of these studies were to identify innate immune biomarkers activated by three classes of CpG ODNs in pigs. For this purpose, we investigated the kinetics of innate immune responses in immune cells from pigs following in vitro and in vivo stimulation with CpG ODNs. The mRNA expression of cytokine and chemokine genes were assayed by SYBR^@ green based quantitative real time PCR. A-class CpG ODN induced significant but transient levels of IFN-γ, IL-12 (P40), IL-6, IL-4 and TNF-α mRNA, C-class CpG ODN induced significant level of IFN-γ, IFN-α and IL-12 mRNA and the lowest level of IL-4 (Th-2 type) mRNA. A very low level of some cytokines stimulation was observed by GC ODNs. It is noteworthy, that IL-12 (P35) mRNA was significantly stimulated by B-class GpC ODN 7909. Interestingly, all classes of CpG ODNs induced significant level of IP-10 at 12 h post stimulation. These in vitro and in vivo observations suggest that interferon-γ inducible protein 10 (IP-10) may be a reliable biomarker for immune activity induced by CpG ODNs in pigs.     

Antioxidative Effects of Astaxanthin against Nitric Oxide‐Induced Oxidative Stress on Cell Viability and Gene Expression in Bovine Oviduct Epithelial Cell and the Developmental Competence of Bovine IVM/IVF Embryos

The aim of the present study was to elucidate the fundamental mechanism of bovine oviduct epithelial cell (BOEC) co‐culture on developmental capacity of bovine in vitro oocyte maturation/in vitro fertilization (IVM/IVF) embryos. We examined the effects of astaxanthin against nitric oxide‐induced oxidative stress on cell viability by MTT assay, lipid peroxidation (LPO) by using thiobarbituric acid (TBA) reaction for malondialdehyde (MDA) and the expression of antioxidant genes (CuZnSOD, MnSOD and Catalase) or apoptosis genes (Bcl‐2, Caspase‐3 and Bax) by RT‐PCR in BOEC. We also evaluated the developmental rates of bovine IVM/IVF embryos co‐cultured with BOEC pre‐treated with astaxanthin (500 μm ) in the presence or absence of sodium nitroprusside (SNP, 1000 μm ) for 24 h. Cell viability in BOEC treated with SNP (50–2000 μm ) lowered, while astaxanthin addition (50–500 μm ) increased it in a dose‐dependent manner. Cell viability in astaxanthin plus SNP (1000 μm ) gradually recovered according to the increase in astaxanthin additions (100–500 mm ). The LPO in astaxanthin group (50–500 μM) gradually decreased in a dose dependent manner and among SNP or astaxanthin plus SNP group, SNP alone and astaxanthin (50 μM) plus SNP shown a significant increase than other groups (p < 0.05). Expression of apoptosis or antioxidant genes was detected by RT‐PCR. Bcl‐2 and antioxidant genes were detected in astaxanthin or astaxanthin plus SNP group, and Caspase‐3 and Bax genes were only found in SNP group. When bovine IVM/IVF embryos were cultured for 6–7 days under co‐culture system such as BOEC treated with astaxanthin in the presence or absence of SNP, the developmental ability to blastocysts in 500 μm astaxanthin group was the highest of all groups. These results suggest that astaxanthin has a antioxidative effect on cell viability and LPO of BOEC, and development of bovine IVM/IVF embryos due to the induction of antioxidant genes and suppression of apoptosis genes.