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The anadromous Geotria australis , one of only three lamprey species representing the early agnathan (jawless) stage of vertebrate evolution in Australia and New Zealand, is declining in abundance. Its adults were caught soon after they had entered rivers on their non-trophic upstream migration and maintained in laboratory tanks for 13–15 months through to spawning. As adult G. australis are susceptible to haemorrhagic septicaemia, they were treated prophylactically and maintained in 3-m3 aquaria supplied with a flow-through charcoal filtration system and UV steriliser. Air temperature and the light : dark regime were constantly adjusted to parallel those in the environment. Males developed the very large suctorial disc and gular pouch characteristic of maturity and both sexes matured at the same time as in the wild. While males frequently showed aggressive behaviour towards each other, the same male and female mated on several occasions. The male coiled around the female and, with his urogenital papilla close to the female's cloaca, twisted and vibrated, leading to egg release. These eggs formed coagulated clusters as in the wild, with many progressing through to the eight-cell stage. Remarkably, numerous G. australis were still alive 95–392 days after the end of the short spawning period, and one male after a further 119 days. Postspawning survival would be facilitated inter alia by extensive proteolysis, reflected in a shortening of the body. The data in this paper emphasise that G. australis is a highly atypical lamprey and provides invaluable information for conserving this declining species. The lamprey Geotria australis , when provided with appropriate conditions, can be maintained in laboratory tanks for many months from the commencement of the upstream migration through to spawning. Successful maintenance requires, however, the provision of conditions that overcome the potential for this species to succumb to haemorrhagic septicaemia. Spawning, which occurs at the same time as in their natural environment, is described. The prolonged period during which G. australis survive after spawning parallels that recorded for this species in its riverine environment and is unique among lampreys. [ABSTRACT FROM AUTHOR]

dults of the Southern hemisphere lamprey Geotria australis were subjected to an exercise/recovery regime at the commencement and end of their 12-15 month non-trophic, upstream spawning migration. In early (immature) migrants and pre-spawning females, muscle glycogen was markedly depleted during exercise, but became rapidly replenished. As muscle lactate rose during exercise and peaked 1-1.5 h into the recovery period, and therefore after muscle glycogen had become replenished, it cannot be the direct source for that replenishment. However, both plasma lactate and glycerol (but not muscle glycerol and glucose) rose sharply during exercise and then declined markedly during the first 0.5 h of recovery and thus exhibited the opposite trend to that of muscle glycogen, implying that these limited pools of glycogenic precursors contribute to glycogen replenishment. Although plasma glucose rose following exercise, and consequently could also be a precursor for muscle glycogen replenishment, it remained elevated even after muscle glycogen had become replenished. While resting pre-spawning females and mature males retained high muscle glycogen concentrations, this energy store became permanently depleted in females during spawning. In mature males, muscle glycogen remained high and lactate low during the exercise/recovery regime, whereas muscle glycerol declined precipitously during exercise and then rose rapidly. In summary, vigorous activity by G. australis is fuelled extensively by anaerobic metabolism of glycogen early in the spawning run and by pre-spawning females, but by aerobic metabolism of its energy reserves in mature males. [ABSTRACT FROM AUTHOR]

The study design included a multidisciplinary examination of the mineral phase of ovine intervertebral disc calcifications. The objective of the study was to investigate the mineral phase and its mechanisms of formation/association with degeneration in a naturally occurring animal model of disc calcification. The aetiology of dystrophic disc calcification in adult humans is unknown, but occurs as a well-described clinical disorder with hydroxyapatite as the single mineral phase. Comparable but age-related pathology in the sheep could serve as a model for the human disorder. Lumbar intervertebral discs ( n = 134) of adult sheep of age 6 years ( n = 4), 8 years ( n = 12) and 11 years ( n = 2) were evaluated using radiography, morphology, scanning and transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray powder diffraction, histology, immunohistology and proteoglycan analysis. Half of the 6-year, 84% of the 8-year and 86% of the 11-year-old discs had calcific deposits. These were not well delineated by plain radiography. They were either: (a) punctate deposits in the outer annulus, (b) diffuse deposits in the transitional zone or inner annulus fibrosus with occasional deposits in the nucleus, or (c) large deposits in the transitional zone extending variably into the nucleus. Their maximal incidence was in the lower lumbar discs (L4/5–L6/7) with no calcification seen in the lumbosacral or lower thoracic discs. All deposits were hydroxyapatite with large crystallite sizes (800–1,300 Å) compared to cortical bone (300–600 Å). No type X-collagen, osteopontin or osteonectin were detected in calcific deposits, although positive staining for bone sialoprotein was evident. Calcified discs had less proteoglycan of smaller hydrodynamic size than non-calcified discs. Disc calcification in ageing sheep is due to hydroxyapatite deposition. The variable, but large, crystal size and lack of protein markers indicate that this does not occur by an endochondral ossification-like process. The decrease in disc proteoglycan content and size suggests that calcification may precede or predispose to disc degeneration in ageing sheep. [ABSTRACT FROM AUTHOR]

The major iron binding protein (IBP) of larval M. mordax has an estimated molecular weight (354,000), subunit molecular weight (18,000) and pI (5.1) identical to those recorded previously for larval G. australis. The IBP in larval G. australis has also been shown to be relatively heat stable and to react immunologically with antihorse spleen ferritin. The weight of total non-haem iron in the whole body, and both the ferritin and haemosiderin iron components, increased with increasing body weight in larval G. australis. While the concentration of ferritin iron remained similar throughout larval life, the concentration of total non-haem iron and haemosiderin iron increased rapidly in animals up to a body weight of 0.1-0.2 g, but thereafter rose only slowly throughout the rest of larval life. This implies that any iron in excess of the amount required for the maintenance of a constant ferritin concentration is converted into haemosiderin iron, and that once non-haem iron has reached a particular concentration (c. 500-600 μg g), the rate of iron accumulation is greatly reduced. While the larvae of both G. australis and M. mordax had very high plasma iron levels (>19,000 μg 100 ml), the former had significantly greater concentrations of iron in the whole body (702 vs. 267 μg g) and more particularly in the nephric fold (7382 vs. 224 μg g). A greater reservoir of non-haem iron could facilitate the maintenance of the large amounts of haem and erythrocytic ferritin present in this species as a result of an exceptionally high haemoglobin concentration and red blood cell number. The greater concentration of non-haem iron in the intestine of M. mordax than of G. australis (1338 vs. 824 μg g), when considered in conjunction with histological studies, indicates that Mordacia mordax eliminates a larger amount of iron during the extrusion of its intestinal columnar cells. [ABSTRACT FROM AUTHOR]

The secreted proteins obtained from nasal washings from eighty-five normal children and fifty asthmatic children, between 6 and 14 years, were investigated by immunological assay for their content of albumin, secretory IgA and IgG. A smaller number of specimens from asthmatic and normal children were examined for their IgE content. There was no statistically significant difference in the levels of albumin, secretory IgA and IgG in the asthmatic and the normal children. The IgE content of nasal wash protein in normal children averaged approximately 70 ng/mg of protein, whereas the IgE content in the asthmatic children averaged greater than 400 ng/mg of wash protein. [ABSTRACT FROM AUTHOR]

Background: Producing graduates for a breadth of sectors is a priority for veterinary science programs. Undergraduate career intentions represent de-facto 'outcome' measures of admissions policy and curricula design, as intentions are strong predictors of eventual behaviour. Informed by Ajzen's Theory of Planned Behaviour, this study aimed to identify if contextually relevant attitudes and self-ratings affect student intentions for veterinary career sectors. Results: Survey responses from 844 students enrolled in five Australian veterinary programs in 2014 were analysed. Intention was measured for biomedical research/academia, industry, laboratory animal medicine, public health/government/diagnostic laboratory services, mixed practice, intensive animal production, companion animal practice, not work in the veterinary profession, and business/entrepreneurship. Hierarchical multiple linear regression analysis enabled comparison of explanation of variance in intent by demographics, animal handling experience, species preference, and attitudes to aspects of veterinary work. Career sector intentions were highest for mixed or companion animal clinical practice, then business/entrepreneurship, then non-clinical sectors. Overall, intent was explained to a greater extent by species preferences than by animal experience, attitudes to aspects of veterinary work and demographics (with the exception of mixed practice intent) with gender having no significant effect. Several variables exerted negative effects on career intent for less popular career sectors. Conclusion: Ajzen's Theory of Planned Behaviour (TPB) provides a framework to increase understanding of and predict career sector intentions. Incorporation of attitude and self-efficacy measures in our study revealed preference for species types contributes greatly to career sector intentions for veterinary students, particularly for the more popular practice based sectors. Importantly, specific species preferences and other attitudes can have a negative effect on intent for non-aligned veterinary sectors. Further research is required to identify additional attitudes and/or beliefs to better explain variance in intent for less popular career sectors. Veterinary admissions processes may benefit from utilising the TPB framework. Identified effects revealed by this study may stimulate innovation in marketing, recruitment, admissions and curricular design, such as timing and role modelling, to utilise positive effects and mitigate against negative effects identified for sectors requiring greater representation of career intent in the student body. [ABSTRACT FROM AUTHOR]

Assessment of general risk posed from transgenic (T) animals is important to their future contributions to society. Identification of potentially harmful properties of transgenic livestock is the initial step in a risk assessment. We previously developed and characterized transgenic swine containing a mammary-specific transgene (bovine a-lactalbumin, bALAC) that results in increased milk production in sows. We are currently determining whether bALAC is expressed in tissues of T swine other than the lactating mammary gland and whether the transgene DNA (Tg) crosses into nontransgenic control (C) swine under various physiological and physical conditions. The specific aims addressed in the present study were to determine (1) whether the Tg can be transferred directly by physical association or contact; (2) whether the Tg can be transferred directly via mating; (3) whether the Tg can be transferred directly during gestation and parturition; and (4) whether the Tg can be transferred directly during lactation. The T animals utilized in these studies are in at least generation 10 and have stable incorporation of the Tg. Comparable age- and weight-matched animals, T and C, were housed together allowing general contact that is normal in swine production, for either 180, 220, or 250 days of age after weaning. Swine typically ingest saliva, regurgitated food, and stool or urinary products, as well as other bodily fluids and cells during normal housing. In the second study, vaginal, cervical, uterine, oviductal, and ovarian tissues from C females on 2, 7, or 90 days after mating to T males, and penis, bulbourethral gland, urethra, testis, and epididymis tissues from C males on 2 or 7 days after mating to Tg females were collected. The presence of Tg in tissues from all C animals was tested by using PCR. We have analyzed for the presence of the Tg in various tissues [including mammary gland, salivary gland, skin (sebaceous gland), muscle, lung, liver, kidney, brain, ovary, oviduct, uterus, cervix, vagina, penis, bulbourethral gland, urethra, testis, epididymis, blood, inner and outer placental membranes and intestine]. Results indicate no presence of the Tg in tissues of C animals (n= 28) after co-habitation for 180, 220, or 250 days (n= 305 samples analyzed) or at 2 (n= 7), 7 (n= 16), or 90 (n= 6) days post-mating (n= 72, 192, or 71 samples analyzed, respectively). At Day 112 of gestation, all the samples (n= 78 samples analyzed) from nontransgenic piglets (n= 13) whose dam was aTg female were negative except for the outer placental membrane (n= 13), which screened positive for the transgene. This is not surprising because the outer placental membrane is in close contact with the uterus of the Tg dam. Finally, control piglets (n= 4) that were cross-fostered (3 days after birth) and suckled Tg dams showed no evidence of the transgene in their tissues (n= 20 samples analyzed) at weaning. The present results suggest that there is no horizontal Tg transmission between T and C pigs caused by rearing, mating, gestation, or lactation. This project was supported by USDA BRAG Project #2005-03799. [ABSTRACT FROM AUTHOR]