Analysis of tidal breathing flow volume loop in dogs with tracheal masses

Objectives To investigate whether there are any changes in the tidal breathing flow volume loop (TBFVL) in calm, non-dyspnoeic dogs with intratracheal masses. Methods We compared 4 dogs with intratracheal masses (group 1) with 10 healthy dogs (group 2). Routine clinical and laboratory examinations of the dogs were unremarkable, except for episodic upper respiratory obstructive signs in the dogs in group 1. Lateral radiography of the neck and thorax showed that group 1 dogs had masses that appeared to protrude into the tracheal lumen. Tracheoscopy and surgery or necropsy was performed to confirm the presence of the mass. Arterial blood gas and TBFVL analysis was carried out in all dogs to assess respiratory status. Results The shape of the TBFVL for dogs in group 1 was narrower and ovoid compared with that for the group 2 dogs. Tidal volume and expiratory and inspiratory times were significantly reduced, whereas the respiratory rate was increased for dogs in group 1 compared with dogs in group 2. Arterial blood gas analysis was unremarkable for all dogs. Conclusions TBFVL is a non-invasive technique that is easy to perform and well tolerated by dogs. In the absence of abnormalities detected by routine diagnostic evaluations and arterial blood gas analysis in dogs with intratracheal masses, the TBFVL contributes to the definition of the physiologic status of the airways at the time of testing, and results suggests that these dogs breathe quite normally when they are calm and non-dyspnoeic.     

Quantification,Morphology and Ultrastructure of Preantral Follicles of Buffalo (Bubalus bubalis) Foetuses

The objective of this study was to determine the number, morphology and ultrastructure of preantral ovarian follicles of buffalo (Bubalus bubalis) foetuses at different ages. Quantification revealed number of primordial, primary and secondary follicles of 48 857 ± 17 506, 26 000 ± 20 452, 18 428 ± 10 875 and 18 375 ± 19 690, 225 ± 349, 326 ± 288 at 12–34 cm and 35–60 cm crown rump length (CRL), respectively. Follicular diameter values were 28.9 (±3.4), 34.7 (±5.9) and 59.4 (±12.6) μm; oocyte diameters were 21.7 (±2.8), 24.3 (±3.4) and 33.0 (±7.7) μm, and the numbers of follicular cells in the follicle equatorial section were 7.1 (±1.4), 12.0 (±2.4) and 13.8 (±2.4) for primordial, primary and secondary follicles, respectively. The primordial follicle consisted of an oocyte surrounded by a layer of flattened follicular cells with a normally eccentric oocyte nucleus. Dispersed Golgi complex, smooth endoplasmic reticulum, rounded mitochondria and several lipid vesicles were observed in the cytoplasm and cell junctions between the follicle cell membranes and the oocyte. This work describes the number, morphometry and ultrastructure of preantral follicles of buffalo foetuses, concluding that folliculogenesis is established between 8 and 34 cm CRL and that follicle number varies individually and according to age and that further studies are needed in this species.     

An outbreak of malignant catarrhal fever in young rusa deer (Cervus timorensis)

On the basis of clinical signs and histological findings eight 9-month-old male rusa deer ( Cervus timorensis ) were diagnosed with sheep associated-malignant catarrhal fever. Following a variable course involving rectal temperatures around 40.5°C, depression, inappetence, diarrhoea, corneal opacity and hypopyon all animals died or were euthanased over a 5-week period. Severe multifocal vasculitis, mainly periglomerular and in the arcuate vessels were consistent histological findings which in the past have been adequate to confirm clinical diagnosis of sheep associated-malignant catarrhal fever. A nested poly-merase chain reaction test has been used to detect a sheep associated-malignant catarrhal fever PRC product, 238 base-pairs in size, in DNA extracted from lymphocyte preparations. The result supported the diagnosis of sheep associated-malignant catarrhal fever in these deer.     

Oogenesis and lipids in gonad and liver of daubed shanny (Leptoclinus maculatus) females from Svalbard waters

Oocyte and liver histomorphology of the daubed shanny (Leptoclinus maculatus) from Isfjorden and Kongsfjorden in Svalbard were investigated during three Arctic seasons: summer (July), autumn (October) and winter (April). Three oocyte developmental phases were observed: primary growth phase, secondary growth phase and maturation phase. We observed four different developmental stages: (1) perinucleolus stage with cortical alveolus formation, (2) lipid droplets formation, (3) vitellogenesis stage and (4) maturation. Late maturation stage of oocytes in the ovaries was from the autumn season. Females accumulated lipids in liver (up to 35.2?% dw) and deposited large amounts of lipids into gonads (up to 52.2?% dw) during maturation. Lipid classes in female gonads changed seasonally, with relative increase in cholesterol during summer and depletion of storage lipids (triacylglycerols and wax esters/cholesterol esters) during the winter. Lipid composition in liver changed during oocyte development and spawning, as neutral lipids were transferred to developing oocytes during summer to autumn. During winter, storage lipids were depleted during starvation. Based on the increase in gonadosomatic index (GSI) with length and observed maturation stages, females seem to mature at a length of about 125-130?mm. The GSI and hepatosomatic index of large females sampled in autumn (September-October) were significantly higher than for females in late winter (April) and spring (May). These results indicate that spawning takes place during winter in Isfjorden and that energy reserves stored in the liver are utilized by females during gonadal development and reproduction.     

Attitudes and practices of Queensland dairy farmers to the control of the cattle tick, Boophilus microplus

Objective To determine practices for the control of cattle ticks on dairy farms in Queensland, the attitudes of farmers to tick infestations and to identify opportunities for and barriers against the introduction of non-chemical methods of tick control.
Design A survey of 199 dairy farmers from tick-infested parts of Queensland was undertaken by 20 dairy advisers and stock inspectors from October 1996 to June 1997. The sample was a proportional, random selection of dairy farms from four regions. A personal interview was conducted with each farmer and answers to 134 questions were obtained.
Results and conclusions Most farmers were not concerned by cattle ticks on their own farms, although they believed that ticks are important to the dairy industry. They were most concerned about the development of chemical resistance by cattle ticks. Inadequate facilities and lack of motivation appeared to be the factors most limiting to improving the methods of control. Most farmers claimed to have only small numbers of ticks at worst. Although a control program recom mended by the Queensland Dairyfarmers' Organisation was well regarded by farmers, few had adopted it. Many farmers saw no need to implement a strategic control program.     

Activity of metabolic enzymes and muscle-specific gene expression in parr and smolts Atlantic salmon <Emphasis Type="Italic">Salmo salar</Emphasis> L. of different age groups

This study was conducted to characterize the energy metabolism level and the features of muscle growth regulation during the development of Atlantic salmon (Salmo salar) inhabiting the Indera River (Kola Peninsula, Russia). The activities of aerobic and anaerobic enzymes (cytochrome c oxidase and lactate dehydrogenase) and carbohydrate metabolism enzymes (glucose-6-phosphate dehydrogenase, glycerol-3-phosphate dehydrogenase, and aldolase) were measured in muscle and liver tissue. Gene expression levels of myosin heavy chain (MyHC), myostatin (MSTN-1a), and myogenic regulatory factors (MRFs—MyoD1a, MyoD1b, MyoD1c, Myf5, myogenin) were measured in the white muscles of salmon parr of ages 0+, 1+, 2+, and 3+ and smolts of ages 2+ and 3+. Multidirectional changes in the activity of enzymes involved in aerobic and anaerobic energy metabolism with age were shown in the white muscles of the parr. The cytochrome c oxidase activity was higher in muscles of underyearlings (0+) and yearlings (1+) and decreased in 2+ and 3+ age groups. The activity of lactate dehydrogenase, in contrast, increased with age. The patterns of changes in expression levels of MyoD1a, MyoD1b, myogenin, MyHC, and MSTN-1a at different ages of the parr were similar. Particularly, the expression of these genes peaked in the yearling parr (1+) and then decreased in elder groups. The differences were revealed in parameters studied between the parr and smolts. The level of aerobic and anaerobic metabolism enzyme activities was higher in the white muscles of smolts than in parr. The activity of carbohydrate metabolism enzymes was decreased in the smolts’ livers. The expression levels of MyHC, MyoD1a, MyoD1b, and myogenin were lower in smolts at age 2+ compared to parr. These findings expand our knowledge of age-related and stage-related features of energy metabolism and muscle development regulation in young Atlantic salmon in their natural habitat. The results might be used for monitoring of the salmon population during restoration and rearing.     

Ultraslow electron spin dynamics in GaAs quantum wells probed by optically pumped NMR

Optically pumped nuclear magnetic resonance (OPNMR) measurements were performed in two different electron-doped multiple quantum well samples near the fractional quantum Hall effect ground state nu = 13. Below 0.5 kelvin, the spectra provide evidence that spin-reversed charged excitations of the nu = 13 ground state are localized over the NMR time scale of about 40 microseconds. Furthermore, by varying NMR pulse parameters, the electron spin temperature (as measured by the Knight shift) could be driven above the lattice temperature, which shows that the value of the electron spin-lattice relaxation time tau1s is between 100 microseconds and 500 milliseconds at nu = 13.     

Fluoride in Tea and Its Risk Assessment

Tea plant absorbs from soil a large amount of fluorine （F） which is accumulated in leaf,resulting in elevated F concentration in tea.It is a controversial topic whether the fluoride in tea is associated with fluorosis.The research advances in F variation of various kinds of tea,factors influencing F level in tea and the associated health risk assessment were reviewed in the present paper.The F level in tea increases with the maturity of the tea leaf.Brick tea had a high F content because it was prepared using mature shoots and old tea leaves as raw material.Some low grade UK supermarket economy teas contained elevated F comparable to the Chinese brick tea.Tea F level is also affected by tea cultivar,soil condition,tea processing method and tea infusion preparation method.     

Effects of l-Ascorbic Acid, α-Tocopherol and Co-culture on In Vitro Developmental Potential of Porcine Cumulus Cells Free Oocytes

The maturation and developmental potential on cumulus-cell-free oocytes is of great importance theoretically and practically. The present study was to investigate the effects of l -ascorbic acid, α-tocopherol and co-culture on in vitro developmental potential of porcine denuded oocytes (DOs). Porcine DOs were cultured in maturation medium supplemented with vitamin C (0, 50, 100, 250, 500, 750 μM) and vitamin E (0, 10, 20, 50, 100, 250 μ m ), respectively. And they were also co-cultured with dispersed cumulus cells (group CCscoculture), intact cumulus cells oocyte complexes (COCs) (group COCscoculture), and COCs whose oocytes were removed (group OOXcoculture), respectively. After 44 h incubation, the maturation rates, cleavage rates and blastocyst rates after parthenogenetic activation in three experiments mentioned above were collected and analysed, respectively. L -Ascorbic acid promoted porcine DOs in vitro maturation and blastocyt development after parthenogenetic activation while α-tocopherol did not increase the in vitro maturation rates, but improved the blastocyst rate. None of the three co-culture manner promoted the in vitro maturation and the cleavage of porcine DOs after parthenogenetic activation, but all the co-culture manners improved the blastocyst rates. Both Vitamin C and E enhance the in vitro developmental potential of porcine DOs. Co-culture increases the developmental potential of porcine DOs.