Variations in the Proportion of Glycolytic/Non-glycolytic Energy Substrates Modulate Sperm Membrane Integrity and Function in Diluted Boar Samples Stored at 15–17°C

In this work the role of energy substrates in the maintenance of boar-sperm survival during storage at 15-17 degrees C was tested. For this purpose, boar spermatozoa were stored at 15-17 degrees C in several defined media with separate combinations of a monosaccharide, glucose and a non-monosaccharide, either citrate or lactate, energy substrates. Our results indicate that the medium containing the highest concentration of glucose together with low lactate levels was the most suitable to maintain sperm quality for 168 h at 15-17 degrees C. This was confirmed after observation of the results of the percentages of viability and altered acrosomes, the osmotic resistance test, the hyperosmotic resistance test and the rhythm of L-lactate production. The survival ability of boar sperm was greater in this experimental medium than in the standard Beltsville Thawing Solution extender, which contains only glucose as an energy substrate, although at a concentration far higher than that of all the tested experimental media. Our results indicate that the exact composition, more than the pure quantity of energy substrates, is a very important modulatory factor which affects survival ability of boar sperm in refrigeration. Thus, the exact combination of several energy substrates would have to be taken into account when optimizing the design of commercial extenders to store boar spermatozoa at 15-17 degrees C.     

Effects of Matrix Filtration of Low-Quality Boar Semen Doses on Sperm Quality

The aim of this work was to develop a method to enhance the sperm parameters of ejaculates with low sperm quality from Piétrain boars. Seminal doses were filtered through columns of DEAE Sephadex (length 2.5 ± 0.5 cm), CM Sephadex (length 5 ± 0.5 cm), glass wool (length 2 ± 0.5 cm) or glass bead (length 10 ± 0.5 cm), with an exit flow rate of 1 ml/40 s in all cases. For each male, 10 ml of the sperm cell-rich fraction diluted at 1 : 6 were filtered. Sperm quality was assessed before and after filtration. Sperm morphology, sperm motility and sperm concentration were determined using the computer program sca ^® 2002 Production, and sperm viability was evaluated by fluorescence multistaining. Osmotic resistance test and hyperosmotic resistance test were used to determine the osmotic resistance of spermatozoa, whereas l -lactate production estimated the metabolic activity. Results showed a decrease of sperm concentration and osmotic resistance of spermatozoa after filtration in the four matrixes. However, an increase in the frequency of viable spermatozoa with intact acrosome after filtration in glass bead columns and an increase of morphologically normal spermatozoa after filtration in Sephadex CM-50, glass wool and glass bead columns were observed. Despite the decrease in the frequency of progressive motile spermatozoa, l -lactate production and mitochondrial sheath integrity maintained constant after filtration. Our findings indicate that column filtration is an effective method to enhance the sperm quality by selecting viable and morphologically normal spermatozoa without altering DNA, plasma membrane, mitochondrial sheath integrity or inducing premature acrosome reaction.     

POSITRON EMISSION TOMOGRAPHY FEATURES OF CANINE NECROTIZING MENINGOENCEPHALITIS

A Yorkshire terrier and a Chihuahua were referred for acute onset, generalized tonic‐clonic seizures and were suspected to have meningoencephalitis based on magnetic resonance (MR) imaging findings. Brain lesions appeared hyperintense with T2‐weighted imaging and hypointense with T1‐weighted imaging, and were characteristic of necrotizing meningoencephalitis. Both dogs were diagnosed with necrotizing meningoencephalitis based on pathologic findings. Fluorine‐18 fluorodeoxyglucose positron emission tomography (FDG‐PET) was performed on both animals before euthanasia with the permission of the owner. In FDG‐PET images, these lesions seen in MR images were characterized by multifocal or diffuse hypometabolism. Our FDG‐PET results provided evidence of glucose hypometabolism in areas of necrosis and cavitation associated with necrotizing meningoencephalitis. FDG‐PET has the potential to provide valuable diagnostic information in dogs with suspected necrotizing encephalitis.     

Acute lethal and behavioral sublethal responses of two stored-product psocids to surface insecticides

BACKGROUND: The psocids Liposcelis bostrychophila Badonnel and L. entomophila (Enderlein) (Liposcelididae) are emerging pests of stored products. Although their behavior, particularly their high mobility, may contribute to the reported relatively low efficacy of insecticides against them, studies to investigate this have not been conducted. The present study aimed to assess the label rate efficacy of three commercial insecticides (β‐cyfluthrin, chlorfenapyr and pyrethrins) applied on concrete surfaces against L. bostrychophila and L. entomophila, and also their sublethal effect on the mobility of these species. RESULTS: The synthetic insecticides β‐cyfluthrin and chlorfenapyr showed high short‐term efficacy (LT₉₅≤15 h) against both psocid species, unlike the natural pyrethrins (LT₉₅ ≥ 4 days). Liposcelis bostrychophila was slightly more tolerant (≥1.2×) than L. entomophila to all three insecticides. Behavioral assays with fully sprayed and half‐sprayed concrete arenas indicated that the insecticides reduced the mobility of both species. Pyrethrins seem to elicit weak repellence in L. bostrychophila. CONCLUSION: β‐Cyfluthrin and chlorfenapyr were effective against both psocid species, but not pyrethrins. The mobility of both species does not seem to play a major role in the differential selectivity observed, but the lower mobility of L. bostrychophila may be a contributing factor to its higher insecticide tolerance. Published in 2008 by John Wiley & Sons, Ltd.     

Adverse drug reactions: Report of the Australian Veterinary Association Adverse Drug Reaction Subcommittee, 1994

Seventy-seven reports of suspected adverse drug reactions (ADRs) were received by the Adverse Drug Reaction Subcommittee (ADRSc) of the Australian Veterinary Association from April 1993 to December 1994 inclusive. The number of reports received/number of animals involved per species were: dogs (32/44), cats (18/31), horses (17/48), and cattle (10/21). Of these, 49 (64%) were classified as definite ADRs and 9 (12%) as probable ADRs. In 11 (14%) reports an ADR could not be substantiated or there was insufficient information available to make a decision. Eight reports were not classified because the manufacturer and the ADRSc disagreed as to the appropriate classification. Sixteen reports involved apparent hypersensitivity reactions, which resulted in death on 6 occasions. Six reports were associated with ‘off label’ use and 1 report with use of an expired product. Of the definite, probable and unclassified reports of suspect ADRs, the most frequent types of drugs involved were antimicrobial drugs (13 reports), anthelmintics (13), insecticides (11), vaccines (10), nonsteroidal anti-inflammatory preparations (5), chondroprotective agents (4), anaesthetic/sedative agents (4) and vitamin preparations (2). Single reports concerning definite, probable or unclassified ADRs to a vasodilator, a corticosteroid, a local anaesthetic and a disinfectant were received.     

Morphological Changes of the Endometrial Epithelium in the Bitch during Metoestrus and Anoestrus

Although cyclic changes of the endometrium in dogs involving both stromal and glandular compartments have been described, the fate of the surface epithelium after progressive growth and secretion is still unclear. In the present study, uteri of 43 healthy bitches in metoestrus and anoestrus were examined macroscopically and histologically. Tissue biopsies were taken from three different locations (cranial and middle parts of uterine horns and bifurcation). The stage of the oestrous cycle was determined by evaluation of progesterone and oestradiol levels in plasma hormone and was also confirmed clinically. Crypts formed in the luteal phase were covered with a columnar epithelium which gradually underwent fatty degeneration. In addition, the stromal part of the crypts disappeared and finally, in early anoestrus, epithelial sheaths desquamated and shed off into the uterine lumen. The surface epithelium was replaced by new cuboidal cells proliferating and migrating from the glandular openings. These findings were confirmed by oil red O staining and immunohistochemical detection of proliferation with Ki‐67 marker.     

Molecular epidemiology of clinical isolates of Pseudomonas aeruginosa isolated from horses in Ireland

Clinical isolates (n = 63) of Pseudomonas aeruginosa obtained from various sites in 63 horses were compared using ERIC2 RAPD PCR to determine their genetic relatedness. Resulting banding patterns (n = 24 genotypes) showed a high degree of genetic heterogeneity amongst all isolates examined, indicating a relative non-clonal relationship between isolates from these patients, employing this genotyping technique. This study characterised 63 clinical isolates into 24 distinct genotypes, with the largest cluster (genotype E) accounting for 10/63 (15.9%) of the isolates. ERIC2 RAPD PCR proved to be a highly discriminatory molecular typing tool of P. aeruginosa in isolates recovered from horses. With the adoption of several controls to aid reproducibility, this technique may be useful as an alternative to PFGE, particularly in epidemiological investigations of outbreaks where speed may be a significant parameter. This is the first report of clonal heterogeneity amongst P. aeruginosa from horses and demonstrated that ERIC RAPD PCR is a rapid method for the examination of this species in horses, which may be useful in outbreak analysis.     

Evidence of shallow fault zone strengthening after the 1992 M7.5 landers, california, earthquake

Repeated seismic surveys of the Landers, California, fault zone that ruptured in the magnitude (M) 7.5 earthquake of 1992 reveal an increase in seismic velocity with time. P, S, and fault zone trapped waves were excited by near-surface explosions in two locations in 1994 and 1996, and were recorded on two linear, three-component seismic arrays deployed across the Johnson Valley fault trace. The travel times of P and S waves for identical shot-receiver pairs decreased by 0.5 to 1.5 percent from 1994 to 1996, with the larger changes at stations located within the fault zone. These observations indicate that the shallow Johnson Valley fault is strengthening after the main shock, most likely because of closure of cracks that were opened by the 1992 earthquake. The increase in velocity is consistent with the prevalence of dry over wet cracks and with a reduction in the apparent crack density near the fault zone by approximately 1.0 percent from 1994 to 1996.     

Heliotropium europaeum poisoning of sheep with low liver copper concentrations and the preventive efficacy of cobalt and antimethanogen

In a field experiment in the Mallee district of Victoria, Merlno xBorder Leicester ewes and wethers grazed Heliotropium europaeum (heliotrope) over periods of 3 to 4 months in 4 successive years. By the end of the second year 12% (14 of 120) of the sheep had died; after 4 years the loss attributable to heliotrope was between 18% and 35%. Mortality was not affected by intraruminal treatment with cobalt or antimethanogen. At the end of the experiment the highest concentration of copper in the liver was 1.95 mmol/kg wet weight (approximately 413 micrograms/g dry weight). The relatively low mortality from primary heliotrope poisoning and the low concentration of copper in the liver of sheep grazing the plant are discussed in relation to the contrasting situation that prevails in the Riverina area of New South Wales. The importance of local environmental factors in the management of heliotrope grazing by sheep is emphasised, particularly in relation to the number of seasons in which the plant may be a major component of the diet.