IMAGING DIAGNOSIS—USE OF RADIOGRAPHY,COMPUTED TOMOGRAPHY,AND ENDOSCOPY IN THE DIAGNOSIS OF ESOPHAGEAL PERFORATION BY AN EXTRA‐LUMINAL TRACHEAL RING PROSTHESIS IN A GOLDEN RETRIEVER

A 6‐year‐old neutered male, Golden retriever presented with regurgitation and excitement‐induced coughing. Two years prior, extra‐thoracic tracheal collapse was diagnosed and extra‐luminal tracheal ring prostheses were placed. Radiographs at presentation showed mineralized and undulant cervical tracheal cartilages. A dorsally broad‐based soft tissue opacity bulged into the caudal cervical tracheal lumen. Esophageal dysmotility and barium accumulation were identified at this level on contrast esophography. Computed tomography showed migration of a prosthetic tracheal ring, resulting in perforation of the esophagus. Hair, foreign material, and dynamic tracheal narrowing were identified on esophagoscopy and tracheoscopy, respectively. Esophagostomy and foreign body removal were performed.     

Ameliorative Effects of Melatonin against Hydrogen Peroxide‐Induced Oxidative Stress on Boar Sperm Characteristics and Subsequent In Vitro Embryo Development

Melatonin, the major secretory product of the pineal gland, scavenges a variety of reactive oxygen and nitrogen species in vivo and in vitro, indicating that melatonin is a potent function as an antioxidant. The objective of this study was to investigate the effect of melatonin in the presence or absence of hydrogen peroxide (H₂O₂) on sperm characteristics (motility, viability, survival rate, membrane integrity, lipid peroxidation (LPO) and mitochondria activity) and also to examine the developmental rates to the blastocysts stage of porcine oocytes fertilized in vitro with semen treated with or without melatonin (100 nm ) in the presence or absence of H₂O₂ (250 μm ). The sperm were treated with melatonin in the presence or absence of H₂O₂ for 3, 6, 9 and 12 h at 37°C and then analysed for the sperm characteristics. The porcine embryos were produced by in vitro maturation and in vitro fertilization (IVM/IVF) using semen treated with or without melatonin (100 nm ) in the presence or absence of H₂O₂ (250 μm ) for 6 h. The semen characteristics, including motility, viability, survival rate, membrane integrity and mitochondria activity, were higher in the groups that were treated with melatonin in comparison to other groups, irrespective of incubation periods. Malondialdehyde levels in control, melatonin and melatonin + H₂O₂ groups were lower than H₂O₂ only group. A positive correlation was shown among motility, viability, survival rate and membrane integrity, but a negative correlation was observed between LPO and the other evaluation methods. The developmental rates to blastocysts of IVM/IVF porcine oocytes fertilized by semen treated with melatonin were significantly increased compared with any other groups, with the cell number of blastocysts shown to have a similar trend to the developmental rates. These results demonstrate that melatonin can improve the semen characteristics during in vitro storage and support the developmental ability of IVM/IVF embryos 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.     

Exogenous DNA Uptake of Boar Spermatozoa by a Magnetic Nanoparticle Vector System

The sperm‐mediated gene transfer method is applicable to transgenesis in many species that use spermatozoa for reproduction recently, which has been shown various results. In the current study, we show that transgenic porcine embryos can be efficiently produced by employing a simple transfection method that uses magnetic nanoparticles (MNPs). The complexes formed between plasmid DNA and MNPs were bounded on ejaculated boar spermatozoa at a higher efficiency compared to methods using DNA alone or lipofection. Using confocal microscopy, rhodamine fluorophore‐labelled MNPs were detected on external surfaces of the spermatozoa membrane, which were bounded on zona pellucida of in vitro maturated oocyte during in vitro fertilization. Electron microscopy revealed that clusters of MNPs were detected in inside of plasma membrane and nucleus of the spermatozoa head. Additionally, we found that magnetofected boar spermatozoa could be fertilized with oocytes in vitro and that the resulting gene of green fluorescent protein was detected in fertilized eggs by genomic PCR analysis. Taken together, these results suggest that MNPs can be used to efficiently introduce a transgene into embryo via spermatozoa.     

Analysis of relationship between crop growth parameters,yield and physical environment within the crop canopy of sesame (Sesamum Indicum) at different sowing dates: Untersuchung der beziehungen zwischen wachstumsparametern,ertrag und physischer umwelt im pflanzenbestand von sesam (Sesamum Indicum) bei verschiedenen aussaatterminen

Relation between crop growth parameters of sesame (Sesamum indicum) and the physical environment within the crop canopy at different sowing dates was studied during the summer seasons of 1999 and 2000. The maximum leaf growth rate (LGR) and leaf area index (LAI) was obtained from February 19 sown crop. About 34.4% variation in LGR could be explained through the variation in the physical environmental elements within the crop canopy. The LAI was depressed in the later months of sowing. The February 19 sown crop produced significantly, the highest dry matter production (DMP) in all the stages of crop growth. The regression model indicated that the crop growth rate (CGR) was adversely affected by the ambient temperature and photosynthetic active radiation (PAR) within the crop canopy. Crops sown on 19 February and 1 March produced statistically similar yields. The cultivar Rama produced higher yields than B-67 and Kanke-1. Regression models suggested that the temperature profile and PAR within the crop canopy produced 69 and 39% variation in yield, respectively.     

Generalized motor seizures after portosystemic shunt ligation in dogs: five cases (1981-1988)

Severe generalized motor seizures developed in 5 dogs between 13 hours and 3 days after surgical attenuation of a single extrahepatic portosystemic shunt. Three dogs died, and a fourth was euthanatized because of poor prognosis for recovery. The fifth dog, although improved, was still not clinically normal 15 months after surgery. An intra-or extracranial cause for the seizures could not be identified in any of these dogs. Postmortem examination results in 3 dogs were similar to findings previously reported in dogs with portosystemic shunts, but which did not undergo surgical shunt ligation. Of the 5 dogs, 4 were greater than 18 months old, which may indicate that older dogs are more likely to develop seizures after shunt ligation than are younger dogs.     

The toxicity of Castanospermum australe seeds for cattle

Two calves given a mean of 16.1 g and 16.4 g ripe Castanospermum australe seeds/kg body weight daily for 13 and 16 days respectively developed haemorrhagic gastroenteritis. The first calf died. The second calf had mild myocardial degeneration and necrosis and mild nephrosis at necropsy. Two calves given a mean of 16.8 g unripe C. australe seeds/kg body weight daily for 18 days remained clinically normal and had mild gastritis at necropsy. The activity of alpha-glucosidase was reduced in the mononuclear cells of peripheral blood and in skeletal muscle. This was attributed to the presence of the indolizidine alkaloid, castanospermine, in the seeds. The toxin causing the gastroenteritis and other lesions is unknown.     

Genomic selection in multi‐environment plant breeding trials using a factor analytic linear mixed model

Genomic selection (GS) is a statistical and breeding methodology designed to improve genetic gain. It has proven to be successful in animal breeding; however, key points of difference have not been fully considered in the transfer of GS from animal to plant breeding. In plant breeding, individuals (varieties) are typically evaluated across a number of locations in multiple years (environments) in formally designed comparative experiments, called multi‐environment trials (METs). The design structure of individual trials can be complex and needs to be modelled appropriately. Another key feature of MET data sets is the presence of variety by environment interaction (VEI), that is the differential response of varieties to a change in environment. In this paper, a single‐step factor analytic linear mixed model is developed for plant breeding MET data sets that incorporates molecular marker data, appropriately accommodates non‐genetic sources of variation within trials and models VEI. A recently developed set of selection tools, which are natural derivatives of factor analytic models, are used to facilitate GS for a motivating data set from an Australian plant breeding company. The power and versatility of these tools is demonstrated for the variety by environment and marker by environment effects.