Prediction of parental combination for introduction of stay-green associated loci in wheat

In wheat, the increase of yield and stability associated traits can be achieved by combining parents containing the stay-green trait and favorable alleles for grain yield. The aim of this work was to analyze the genetic dissimilarity between wheat lines from stay-green and synchronized maturation groups and elite cultivars. Moreover, to propose promising combinations seeking the selection of high-grain yield and high bread-making quality genotypes containing stay-green trait. The experiment was conducted in a randomized block design with three replications in 2003, 2004, and 2005, using sister-lines with the presence and absence of stay-green trait and elite cultivars. Genetic variability exists among wheat strains from the synchronized stay-green maturation group and elite cultivars. Genotypes of maturation group stay-green obtained an average performance superior to the synchronized group. Crosses between stay-green lines and the CEP 29 and BRS 177 cultivars are promising in the selection of genotypes carrying the stay-green trait with high yield and bread-making quality.     

Assessing seed desiccation responses of native trees in the Caribbean

New Forests - Native trees from the Caribbean were tested for seed desiccation responses, by adapting the “100-seed test” protocol. Ninety-seven seed lots of 91 species were collected...     

High‐throughput Cryopreservation of Sperm from Sex‐reversed Southern Flounder,Paralichthys lethostigma

The Southern flounder, Paralichthys lethostigma, is a valuable aquaculture fish with established markets in the USA. All‐female production in this species is an important technology for aquaculture because the females usually have body sizes twice those of males at the same age, and sex‐reversed males (genotypic XX neomales) are used for all‐female production by crossing with genetically normal females. However, sperm volume from the neomales is usually small (<0.5 mL) and limits their application for all‐female fish production. Cryopreservation of sperm from these sex‐reversed neomales will provide access on demand with increased efficiency to extend the application of neomales. The goal of this study was to develop a protocol for cryopreservation of sperm from the Southern flounder by using an automated high‐throughput processing system. The objectives were to: (1) determine the effect of osmolality on activation of sperm motility; (2) evaluate the effect of extender solutions on sperm motility capacity; (3) evaluate the acute toxicity of cryoprotectants (dimethyl sulfoxide [DMSO], propylene glycol, and polyethylene glycol) on sperm motility, and (4) estimate the effect of cooling rate on sperm cryopreservation and post‐thaw fertilization. Sperm motility was activated when osmolality was 400 mOsmol/kg or higher. Of the three extender buffers tested, HEPES4‐(2‐hydroxyethyl)‐1‐piperazineethanesulfonic acid (HEPES) at 300 mOsmol/kg resulted in better protection for sperm motility than did Hanks' balanced salt solution and Mounib solution at 300 mOsmol/kg during 7 d of refrigerated storage. After 30 min equilibration with the cryoprotectant of 15% DMSO, sperm motility was 24 ± 21% (fresh sperm motility without any cryoprotectants was 42%). After cooling at a rate of 20 C/min, post‐thaw sperm motility was 8 ± 5% and fertilization was 63 ± 40% evaluated at the 32–64 cell stage (5 × 10⁵ sperm per egg). Overall, a protocol was developed for sperm cryopreservation in the Southern flounder with high‐throughput processing, which provides a tool to preserve the valuable genetic resources from neomale flounders, and enables germplasm repository development for the Southern flounder.     

Equine intravenous glucose tolerance test: glucose and insulin responses of healthy horses fed grain or hay and of horses with pituitary adenoma

Intravenous glucose tolerance testing (0.5 g/kg of body weight) was done on 2 groups of healthy horses maintained with hay (group 1, n = 5) and with hay plus grain supplementation (group 2, n = 5) and on a group of horses with clinically diagnosed pituitary adenoma (group 3, n = 10). Healthy horses showed an immediate increase of plasma glucose concentration after the IV glucose injection, with return of values to base line in 1 hour. Group 3 horses showed resting hyperglycemia and a delayed return of glucose values to base line (3 hours). Group 3 horses showed resting hyperinsulinemia and a feeble (nonsignificant) response to the glycemic stimulus, with gradual decrease of insulin values to base line. In addition to the apparently reduced tissue sensitivity to insulin in group 3 horses, as evidenced by hyperglycemia, hyperinsulinemia, and protracted glucose and insulin curves, the initial decrease in the insulin/glucose ratio indicates that there was secretory deficiency in response to acute IV glucose loading.     

Spontaneous listeric encephalitis and neuritis in sheep. Light microscopic studies

Sixteen of 17 sheep with spontaneous listeric encephalitis had neuritis characterized by diffuse and focal intrafascicular and perineural accumulations of lymphocytes, plasma cells, macrophages and neutrophils in one or more cranial nerves. Nine sheep had extensive trigeminal neuritis which was usually unilateral. Brain lesions were mainly in the stem and were foci of macrophages or neutrophils or both, malacia, neutrophilic neuronophagia, vascular cuffing, and meningitis. Lesions in the brain and trigeminal ganglia were most severe on the same side as the affected trigeminal nerve. Gram-positive bacilli were in proximal parts of cranial nerves in foci of inflammatory cells and occasionally in morphologically intact nerve fibers. Organisms in the brain were in phagocytes in areas of inflammation and in scattered neurons and axons. The results were consistent with centripetal migration of the infectious agent along one or more branches of the trigeminal nerve to the brain and dissemination in the brain stem occurring, at least partly, along fiber tracts. Intraaxonal movement of bacteria probably is a mechanism involved in the pathogenesis of this disease.     

Results of a Preliminary Trial with Sphaerophorus necrophorus Toxoids to Control Liver Abscesses in Feedlot Cattle

A preliminary field experiment was undertaken to evaluate the efficacy of alum precipitated toxoids of Sphaerophorus necrophorus prepared from sonicated whole cells and cell fractions to reduce the incidence of bovine abscesses. A total of 108 calves were divided into five groups and treated as follows: I. uninoculated control, II. adjuvant inoculated control, III. 15.5 mg protein of sonicated (fragmented cells) toxoid, IV. 10.5 mg protein of cytoplasmic toxoid. V. 15.5 mg protein of cytoplasmic toxoid. All animals were maintained under similar conditions to those prevailing in feedlots in Alberta. Livers were examined at slaughter. The most promising result was achieved with the injection of 15.5 mg protein of cytoplasmic toxoid. In this treatment group, no scars (healed lesions) were found in the liver and the incidence of liver abscesses was reduced to 10% from the average 35% liver abscesses and scars found in the uninoculated and adjuvant inoculated groups. The toxoid from sonicated whole cells did not reduce liver abscess incidence. These data suggest that the incidence of liver abscesses in cattle fattened in feedlots may be reduced by immunization.     

SDS-PAGE and Western blot of urinary proteins in dogs with leishmaniasis

Canine leishmaniasis is an endemic disease in the Mediterranean area caused by the protozoan Leishmania infantum, which usually produces renal failure. Sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blot using antibodies to IgG and IgA from dogs were carried out in the urine of 22 dogs with leishmaniasis diagnosed by ELISA and confirmed by PCR, and 20 healthy dogs. The results were compared to renal function laboratory tests and to those from a histopathological study of the kidneys from sick animals that died naturally or were euthanized. Five different bands with molecular weights ranging from 10 to 110 kDa were obtained from the electrophoresis of the urine of healthy dogs. 33.5% of total proteins corresponded to low molecular weight proteins and the other proteins had middle and high molecular weights. However, in the group with leishmaniasis, a maximum of 11 different bands with molecular weights ranging from 10 kDa to 150 kDa were displayed in the electrophoresis of the urine. The urine electrophoretic pattern in the sick dogs was classified as mixed (proteins with high and low molecular weights) because low molecular weight proteins made up 57.9% and the rest of the proteins had middle and high molecular weights. In Western blot, none of the healthy dogs showed excretion of IgG and/or IgA, whereas IgG and IgA were detected in the Western blot of urine of 68% and 55% respectively of dogs with leishmaniasis. The results obtained in the leishmaniasis group agreed with glomerular and tubular damage, which were confirmed by the histopathological findings.     

Transplacental transfer of propofol in pregnant ewes

Propofol is an injectable anaesthetic that is currently used both in veterinary and human medicine for the induction and maintenance of anaesthesia. Although little is known about the pharmacokinetics of propofol in fetuses, it is widely used in obstetric procedures, particularly in caesarean section. This study determines the pharmacokinetics of propofol in pregnant ewes in the last third of pregnancy, and placental transfer and pharmacokinetics in fetuses after the administration of a 6 mg/kg intravenous (i.v.) bolus (phase 1) or a 6 mg/kg i.v. bolus followed by continued infusion of 0.4 mg/kg/min. In ewes, the area under the blood concentration-time curve (AUC) and C(max) (8.6 mgh/mL and 9.5mg/mL, respectively) was higher than those of the fetus (1.6 mgh/mL and 1.19 mg/mL, respectively). The mean half-life was 0.5h in the dam and 1.1h in the fetus.