bluuebunny/crossref_metadata_2025 huggingface dataset:
X-ray Induced Activity of N-Ethylmaleimide-Sensitive DNA Polymerase in Chinese Hamster Cells
Authors: Ramsay RG , Westerman M
Published: July 2016

Chinese hamster DDN cells have been exposed to low doses of X-irradiation � 15 Gy). These doses have been shown to induce significant levels of repair replication. Levels of activity of DNA polymerase were subsequently measured in cells exposed in G 1 phase of mitosis to 7�5 Gy of X-rays. Following exposure, the activity of this enzyme was observed to rise to a peak within 15 min postirradiation, then decline and then rise again over a long period. The initial rise at least was found to be sensitive to inhibition by N-ethylmaleimide, a known inhibitor of DNA polymerase-o< and DNA polymerase-y at the concentration used. It is therefore suggested that repair of X-ray-induced damage in these DON cells was at least in part dependent upon induced DNA polymerase activity and this may involve DNA polymerase-o< or DNA polymerase-y, or both.
Influenza Virus Haemagglutinin. Structural Predictions Suggest That the Fibrillar Appearance is Due to the Presence of a Coiled-Coil
Authors: W Ward Colin , A Dopheide Theo
Published: July 2016

Predictions of secondary structure for the two chains HAl and HA2 of the haemagglutinin from the Hong Kong influenza virus AjMemphisjl02j72 reveal a striking contrast between the potential conformations of the two chains. HAl is predicted to be rich in ft-structure while HA2 is highly helical. The predictions further suggest that coiled-coil type interactions between the central helical segments of the HA2 chains may hold the haemagglutinin monomers together in the virus.
Rates of Removal of Exogenous and Endogenous Glucagon From the Plasma of Sheep in Vivo
Authors: P Brockman Ronald
Published: July 2016

The removal of exogenous and endogenous glucagon from plasma was determined in vivo in sheep weighing 53�1 (mean�s.e.) kg. Porcine glucagon was infused intravenously for 90 min. The metabolic clearance rates (MCR) were determined from plateau immunoreactive glucagon (IRG) concentrations in plasma and infusion rates of glucagon. The mean clearance rate (�s.e.) was 16�7�1�6 litres per hour (n = 20). Upon termination of the infusion, the decrease in IRG concentrations in plasma was determined. Least-squares regression analysis of non-linear functions indicated the data fit a two-component exponential function. The time constant for the rapid component of the plasma IRG disappearance function was -0�32�0�04 min- 1 (mean�s.e.). The time constant for the slow component was -0�022�0�008 min-'. The rate of removal of endogenous glucagon was estimated during the infusion of somatostatin when glucagon secretion was inhibited. The time constants (mean�s.e., n = 8) for the decrease in IRG during somatostatin infusion were -0�42�0�08 and -0�003�0�002 min-' for fast and slow components, respectively. The time constants for the rapid components of exogenous and endogenous glucagon were not significantly different. This suggests that endogenous and exogenous glucagon are similarly removed from plasma.
Investigations of Ultradian and Circadian Rhythms in the Concentration of Cortisol and Prolactin in the Plasma of Dairy Cattle
Authors: Fulkerson WJ , Sawyer GJ , B Gow Christine
Published: July 2016

This experiment analysed the circadian and ultradian pattern of secretion of cortisol and prolactin in cattle, and from this a meaningful sampling technique for these hormones has been suggested.
An Electrophoretically Cryptic Alcohol Dehydrogenase Variant in Drosophila Melanogaster. 11. Post-Electrophoresis Heat-Treatment Screening of Natural Populations
Authors: Wilks AV , Gibson JB , Oakeshott JG , Chambers GK
Published: July 2016

The two common genetic variants of alcohol dehydrogenase in D. melanogaster, ADH-F and ADH-S, differ in substrate specificity and electrophoretic mobility. A third inherited variant, ADH-FCh.D., has a substrate specificity like ADH-S, an electrophoretic mobility like ADH-F, but much greater thermostability than either of the others. ADH-FCh.D. can be identified after post-electrophoresis heat treatment (15 s at 43�C) on cellulose acetate sheets. The AdhFCh?D ? allele has been found in 19 of 34 natural populations in Australasia but its frequency in these populations does not exceed 0�06. The partial correlation between AdhFCh ?D ? frequency and a maximum temperature variable is significant and positive among the Australasian populations although different climatic associations are found for a thermostable form of ADH-F in North America.
Sulfur-Selenium Studies in Sheep. II. Effect of a Dietary Sulfur Deficiency on Selenium and Sulfur Metabolism in Sheep Fed Varying Levels of Selenomethionine
Authors: White CL
Published: July 2016

The effect of a sulfur deficiency on the metabolism of selenium and sulfur was investigated in eight merino wethers. The sheep were fed high-sulfur (2 g S/kg) or low-sulfur (0�5 g S/kg) diets for two periods of 35 days each, and received selenium as selenomethionine at dietary concentrations of 0�02,0�06,0�09 and 0�67 mg Se/kg.
Critical Time Period for the Vagino-cervical Stimulus to Induce Pseudopregnancy in the Dioestrous Rat
Authors: Soares MJ , Chamley WA
Published: July 2016

Groups of rats experienced mechanical stimulation of the vagino-cervical region to induce pseudopregnancy at various intervals from 0900 h on dioestrus - 1 (D - 1) to 1800 h on D - 2. Twentyfour of 26 rats which were stimulated on D - I experienced immediate pseudopregnancy whereas when the stimulus was given on D-2, 39 of 45 rats continued to cycle and the latest time when such mechanical stimulation would reliably induce immediate pseudopregnancy was 2400 h on D-l. Abolition of the dark phase between 1800 h D-l and 0600 h D-2 did not alter this critical time period (2400 h on D-I). Stimulation as late as 1200 h on D-2 caused alterations in the normal pattern of 4-day cyclicity in 8 of 11 rats.
Fertilization of Pronase-Treated Mouse Ova in Vitro
Authors: Quinn P , Stanger JD
Published: July 2016

In order to obtain consistently a large number of zona-free mouse ova for studies of sperm-egg interactions, a study was made of the relative effectiveness of removing the zona pellucida from ova by mechanical or enzymatic treatments. Ova exposed to pronase before mechanical removal of the zona pellucida in medium devoid of pronase had similar fertilization rates in vitro compared with ova mechanically denuded in the absence of pronase. Ova with pronase-weakened zonae were easier to denude and survived the mechanical manipulations better than the ova denuded by vigorous aspiration in narrow-bore pipettes. However, exposure to pronase did significantly lower the incidence of polyspermy in the naked ova, indicating that some of the enzyme may have diffused across the perivitelline space and damaged sperm-binding sites on the vitelline plasma membrane. The enzyme treatment also reduced the fertilization rate of zona-intact ova.
Hormonal Correlates of Follicular Development in the Human Ovary
Authors: P McNatty Kenneth
Published: July 2016

This review summarizes recent studies pertaining to follicular development in the human ovary. Some of these studies were concerned with characterizing the steroidogenic capacity of the individual cell types of the follicle in relation to whether the follicle was healthy or atretic. Other studies covered in this review concern the oocyte and its hormonal environment both in vivo and in vitro, the effects of steroids and gonadotrophins on the steroidogenic potentials of follicle cells and also some endocrine and non-endocrine responses of thecal and granulosa cells after being separated and then recombined in vitro. The data are integrated in relation to the development of a follicle during the follicular phase of the menstrual cycle.
Effects on the Secretion of Pituitary Growth Hormone, Thyroid Stimulating Hormone, Luteinizing Hormone and Follicle Stimulating Hormone in Rats Rendered Hyperprolactinaemic by Chronic Treatment with Oestrogen
Authors: Smythe GA , Brandstater JF , Vining RF
Published: July 2016

The induction of hyperprolactinaemia in the male rat following chronic high-dose oestrogen administration over 3 months was associated With a significant inhibition of the secretion of growth hormone (OH) (P < 0�02) thyroid stimulating hormone (TSH) (P < 0�0025), luteinizing hormone (LH) and follicle stimulating hormone (FSH) (both P < 0�01). Acute, but not chronic, administration of bromocriptine (1 mg/kg) to these hyperprolactinaemic animals had the effect of normalizing the serum levels of GH and TSH but not those of LH or FSH. While the effects observed on GH, TSH, LH and FSH following induction of hyperprolactinaemia are likely to be consequential to brain actions of prolactin, the present data do not exclude the possibility of direct actions of oestrogen itself.
Repeated DNA Sequences and Kangaroo Phylogeny
Authors: Peacock WJ , S Dennis E , Elizur A , Calaby JH
Published: July 2016

Three highly repeated DNA sequences have been used to determine relationships of species within the Macropodidae (kangaroos and wallabies). Two highly repeated DNA sequences were isolated as buoyant density satellites in the red-necked wallaby and in the wallaroo-euro group. The third probe was a cloned representative of one class of highly repeated species from the red kangaroo.
Immunization of Sheep With Larval Antigens of Lucilia cuprina
Authors: O'Donnell IJ , Green PE , Connell JA , Hopkins PS
Published: July 2016

Sheep were immunized with antigens extracted from third-instar larvae of L. cuprina. This procedure produced substantial titres of circulating antibody as measured by solid-phase radioimmunoassay or immunodiffusion or by both techniques. However, immunization did not confer protection against subsequent implant challenge with first-instar larvae. In vitro studies indicated that pooled sera from immunized sheep (mean immunodiffusion titre = 3) significantly reduced larval survival. Antigen specificity and the modulating effects of concomitant humoral responses to larval challenge are discussed in relation to the findings.
Progesterone Control of the Initiation of Lactose Synthesis in the Rat
Authors: Nicholas KR , Hartmann PE
Published: July 2016

The in vitro incorporation of ['4C]glucose into lactose in mammary tissue, the concentration of lactose in the mammary tissue and the concentration of lactose in the mammary secretion were determined during late pregnancy and lactation in the rat. These changes were related to the decline in blood progesterone during late pregnancy.
The Foetoplacental Unit and the Initiation of Lactation in the Rat
Authors: Nicholas KR , Hartmann PE
Published: July 2016

Rats were either Caesarean-sectioned, ovariohysterectomized or ovariectomized on day 19 of gestation anti the role of prolactin and corticosteroids in the initiation of lactation was studied by administering 2~bromo-lX-ergocryptine (CB 154) and prolactin, and by using adrenalectomy and foetectomY. The concentrations of corticosteroids and prolactin in the plasma and the weight and lactose content of the inguinal mammary glands were determined 48 h after Caesarean section, and 24 h after ovariohysterectomy and ovariectomy.
Induction of Ovulation in Seasonally Anovular Ewes by the Introduction of Rams: Effects of Progesterone and Active Immunization Against Androstenedione
Authors: B. Martin Graeme , J Scaramuzzi Rex , R Lindsay David
Published: July 2016

The effects of progesterone priming and active immunization against androstenedione on ovulation, oestrus and premature luteal regression were observed in seasonally an ovular Merino ewes which had been induced to ovulate by the introduction of rams, Ovulation was induced in 27 out of 36 ewes, and the response was not affected by either immunization or progesterone priming, The ovulation rate (mean number of ovulations per ewe ovulating) was higher in ewes immune to androstenedione, but there was no significant effect of this treatment on oestrus or luteal maintenance
Effects of Photoperiod and Feeding on Plasma Corticosteroid Concentrations and Maximum Corticosteroid-binding Capacity in Pigs
Authors: Barnett JL , Winfield CG , Cronin GM , Makin AW
Published: July 2016

The effects of time of feeding and photoperiod on the circadian rhythm of total and free plasma corticosteroid concentrations and the maximum cortIcosteroid-binding capacity (MCBC) were measured in pigs. There were four photoperiod treatments: natural long and short daylengths (light:dark,14:10; 10!:13!. respectively), artificial short daylength and reverse artificial short daylength (light: dark, 9: 15).
Vascular Changes During Regression of the Corpus Luteum of the Guinea Pig
Authors: Hossain MI , O'Shea JD
Published: July 2016

Quantitative and qualitative changes in the microvasculature of the corpus luteum of the guinea pig during cyclical luteal regression were studied by light and electron microscopy. During luteal regression, between day 12 of the oestrous cycle and day 1 of the next cycle, there was a reduction in the extent of the luteal capillary bed as measured both by 'hit' counts and by differential counts of all nucleated cells. Luteal cells made up a constant proportion of :::::: 60 % of the luteal tissue area up to day 1 of the next cycle, but had increased as a proportion of all nucleated cells by that stage. Both fibroblasts and macrophages increased in number and in area occupied during luteal regression. Ultrastructural changes in capillaries during luteal regression included, an increased incidence and degree of protrusion of endothelial cells into the lumina of small blood vessels, and degeneration and death of many endothelial cells. In spite of the widespread presence of endothelial cell degeneration, most small vessels retained a continuous lining of apparently viable endothelium. It is concluded that in this species there is a rapid and substantial reduction in the luteal capillary bed, which commences during the early stages of luteal regression, and a mechanism is proposed by which the capillary bed may be reduced while retaining its integrity.
Carboxymethylation of Thiol Groups in Ovalbumin: Implications for Proteins that Contain Both Thiol and Disulfide Groups
Authors: Webster DM , Thompson EOP
Published: July 2016

The cysteine residues of hen ovalbumin were S-carboxymethylated with non-radioactive iodoacetic acid under various conditions by altering the pH at which the protein was denatured in 8 M urea, by using different molar ratios of non-radioactive iodoacetic acid to cysteine and by varying the time at which carboxymethylation was commenced after denaturing conditions had been applied. Under the various conditions, the thiol groups were carboxymethylated to different extents, the residual thiol groups being measured by reaction with 5,5'-dithiobis(2-nitrobenzoic acid) in the presence of sodium dodecyl sulfate. When ovalbumin is carboxymethylated in alkaline urea, it unfolds slowly and the carboxymethylation is incomplete even with 150-fold excess iodoacetic acid. The known rapid thiol-disulfide exchange that occurs at alkaline pH values makes this method of carboxymethylation unsuitable as a preliminary step for blocking the native cysteine residues of ovalbumin before reduction and labelling the thiol groups formed by reduction of the disulfide bonds. Titration of the thiol groups of ovalbumin in 6 M guanidine hydrochloride or 1 % (w/v) sodium dodecyl sulfate at pH 8�2 with 5,5' -dithiobis(2-nitrobenzoic acid) is more rapid than in 8 M urea and these solvents would be preferable for studies of the disulfide-bonded sequences. Denaturation of ovalbumin in acidic 8 M urea is a very rapid process, and under mild acid conditions thiol-disulfide interchange is much slower. Subsequent carboxymethylation of the cysteine residues at alkaline pH with 150-fold excess iodoacetic acid results in complete carboxymethylation and the carboxymethylated ovalbumin can be reduced and labelled with radioactive iodoacetic acid with specific labelling of the half-cystine residues involved in the disulfide bond. The results are discussed in relation to the allocation of half-cystine residues in other protein systems that contain both thiol and disulfide groups.
Effects of Scopolamine Hydrobromide on the Development of the Chick and Rabbit Embryo
Authors: McBride WG , Vardy PH , French J
Published: July 2016

When 100 or 200 µg of scopolamine hydrobromide were injected into hen eggs after they had been incubated for 96 h the major malformations of the embryo found were gastroschisis, exencephaly, reduction deformities of the limbs, microphthalmia and buphthalmia when the eggs were opened on the 12th day of incubation.
Eight foetuses of one of eight New Zealand white rabbit does given scopolamine hydrobromide at the rate of 473 µg/kg in their drinking water from the 10th to the 14th day of gestation showed malformations consisting of microphthalmia, buphthalmia, exencephaly and hydrocephaly. A second doe which similarly received 520 µg/kg of the hydro bromide had four malformed foetuses showing microphthalmia and had two foetuses which were resorbed. However, there were no malformations in foetuses of eight does given bolus doses of scopolamine hydrobromide ranging from 37 to 184 µg/kg by intramuscular injection every 12 h from the 10th to the 14th day of gestation.
Results indicate interference by the drug with the function of the cholinergic nerves on the development of the chick and rabbit embryo.
Development of Preimplantation Mouse Embryos in vivo and in vitro
Authors: Harlow GM , Quinn P
Published: July 2016

The culture conditions for the development in vitro of (C57BL/6 X CBA) F2 hybrid two-cell embryos to the blastocyst stage have been optimized. Commercially available pre-sterile disposable plastic culture dishes supported more reliable development than re-usable washed glass tubes. The presence of an oil layer reduced the variability in development. An average of 85 % of blastocysts developed from hybrid two-cell embryos cultured in drops of Whitten's medium under oil in plastic culture dishes in an atmosphere of 5% O2 : 5% CO2 : 90% N2 ? The time taken for the total cell number to double in embryos developing in vivo was 10 h, and in cultured embryos 17 h. Embryos cultured in vitro from the two-cell stage to blastocyst stage were retarded by 18-24 h in comparison with those remaining in vivo. Day-4 blastocysts in vivo contained 25-70 cells (mean 50) with 7-28 (mean 16) of these in the inner cell mass. Cultured blastocysts contained 19-73 cells (mean 44) with 8-34 (mean 19) of these in the inner cell mass. In the uterine environment, inner-cell-mass blastomeres divided at a faster rate than trophectoderm blastomeres and it is suggested that a long cell cycle is associated with terminal differentiation. Although cultured blastocysts and inner cell masses contained the same number of cells as blastocysts and inner cell masses in vivo, the rate of cell division in cultured inner cell masses was markedly reduced.
Pattern of Cortisol Release in Sheep following Administration of Synthetic ACTH or Imposition of Various Stressor Agents
Authors: Fulkerson WJ , A Jamieson Pamela
Published: July 2016

This paper describes experiments with sheep, in which changes in plasma cortisol, after imposition of various stressor agents, were compared to the changes following administration of synthetic ACTH. The influence of stress associated with shearing, yarding, oestrogen administration (30 Jlg oestradiol benzoate, i.v.), feeding and fasting on the plasma concentration of cortisol was monitored in four mature Merino ewes. They were placed in the experimental environment for 21 days before monitoring began. The ewes were treated in pairs, each pair being visually and acoustically isolated from the other. One pair of ewes was exposed to the particular stress and the remaining pair acted as their own controls. The treatments were reversed 2 days later. In the second part of the experiment, 0, 0'01, 0'1,1'0 or 10�0 i.u. synthetic ACTH were injected as an intravenous bolus, after endogenous secretion had been suppressed by administration of synthetic glucocorticoid. All blood samples were taken via an indwelling jugular catheter. A comparison of cortisol release-estimated from a plot of cortisol in plasma versus time-following imposition of various stressor agents and administration of synthetic ACTH, allowed stress to be defined in terms of synthetic ACTH equivalents. The most severe stress was associated with shearing (0' 84 i. u. synthetic ACTH equivalents), less stress was imposed by yarding and handling (0'45 i.u.), and there appeared to be no effect attributable to feeding, fasting or oestrogen administration. The similarity in the pattern of cortisol release following ACTH administration offers the possibility of defining acute, but not chronic, stress in terms of ACTH equivalents.
The Endocrine Control of Male Phenotypic Development
Authors: D Wilson Jean , E Griffin James , WGeorge Fredrick , Leshin Mark
Published: July 2016

Male and female embryos develop in an identical fashion during the initial portion of gestation. If the indifferent gonad differentiates into an ovary (or if no gonad is present), a female phenotype is formed. Male phenotypic differentiation, however, requires the presence of an endocrinologically active testis. Two secretions of the foetal testis, Mullerian-inhibiting substance and testosterone, are responsible for male development. Testosterone itself is responsible for virilization ofthe Wolffian duct system into the epididymis, vas deferens, and seminal vesicle, whereas dihydrotestosterone induces development of the prostate and male external genitalia. Thus, impairment of dihydrotestosterone formation results in a characteristic phenotype consisting of predominantly female external genitalia but normaIly virilized Wolffian ducts. The molecular mechanisms by which testosterone and dihydrotestosterone act during foetal development appear to involve the same high affinity receptor, a protein that transports both testosterone and dihydrotestosterone to the nucleus of target cells. When this receptor is either absent, deficient, or structurally abnormal, the actions of both testosterone and dihydrotestosterone are impaired, and the resulting developmental anomalies involve both internal and external genital structures.
Comparison of Sulfate Metabolism in Costal Cartilage of Normal and 'Little' Mice
Authors: M McKern NeiI
Published: July 2016

C57BL/6J and mutant 'little' (lit/lit) mice c. 50 days of age were injected with doses of [35S]sulfate proportional to their body weight. Despite the diminished growth rate of lit/lit mice compared with normal mice at this age, uptake of radioactivity per unit mass of cartilage was similar for both mouse types, confirming previous data. Additional experiments with these mice established that the similarity of sulfate uptake could not be accounted for by differences in the location of bound sulfate or (for females) by differences in cartilage cellularity. Investigation of sulfate loss by costal cartilage in vivo indicated that cartilage degradation occurred at a greater rate in lit/lit mice than in normally growing mice. These latter data suggest that growth hormone, which is lacking in lit/lit mice, may in part regulate skeletal growth (at least for female mice) by inhibiting degradation of cartilage.
Effects of 6-Methoxy-l,2,3,4-tetrahydro-b-carboline and Yohimbine on Hypothalamic Monoamine Status and Pituitary Hormone Release in the Rat
Authors: Smythe GA , W Duncan M , Bradshaw JE , Nicholson MV
Published: July 2016

Shortly after administration of 6-methoxy-1,2,3,4-tetrahydro-ft-carboline (6-MeOTHBC) and yohimbine to normal or hypothyroid rats [the latter exhibiting chronically elevated levels of serotonin (5-HT) neuronal activity in the hypothalamus] there was a highly significant increase in hypothalamic noradrenaline (NA) activity and in ACTH release concomittant with a reduction in hypothalamic 5-HT activity (P< 0'01) and in growth hormone (GH) (P<O'01) and in thyroid stimulating hormone (TSH) (P< 0'01) release from the pituitary. Both compounds caused an increase in hypothalamic dopamine (DA) metabolism and in pituitary prolactin (PRL) release in normal rats (P<0'01) but only yohimbine exerted this action in hypothyroid rats. Lower doses of 6-MeOTHBC exerted a relatively specific effect in hypothyroid rats, reducing (P< 0�01) 5-HT neuronal activity in parallel with pituitary TSH secretion (P<0�05). While gross effects of 6-MeOTHBC and yohimbine were similar with respect to their effects on NA and 5-HT status in the hypothalamus, there were quantitative differences. 6-MeOTHBC always caused a greater decrease in 5-HT turnover and a lesser increase in NA turnover than did yohimbine.
Natural Selection and the Maintenance of Colour Pattern Polymorphism in the Australian Plague Locust Chortoicetes terminifera
Authors: M Dearn John , AH Davies Richard
Published: July 2016

Twelve samples of C. termini/era from seven locations in eastern Australia were analysed for colour pattern polymorphism. Although there was heterogeneity between the samples the overall frequencies of the colour pattern genotypes were very similar. Males and females showed consistent differences in their genotype frequencies and this is presumed to reflect differential selection between the two sexes. A comparison between observed genotype frequencies and those expected under random mating and in the absence of selection revealed large differences. In particular, genotypes heterozygous for two dominant genes were consistently underrepresented. While these differences could result from non-random mating it is argued that they are more likely to be due to viability differences between the genotypes.
Isozyme Uniformity and Virulence Variation in Puccinia graminis f. sp. tritici and P. recondita f. sp. tritici in Australia
Authors: Burdon JJ , Luig NH , Marshall DR
Published: July 2016

During a routine survey of pathotypes of Puccinia graminis f. sp. tritici (the wheat stem rust pathogen) and P. recondita f. sp. tritici (the wheat leaf rust pathogen) present in Australia during the 1981-82 growing season, 16 pathotypes of P. graminis tritici and 12 pathotypes of P. recondita tritici were detected in total samples of 193 and 180 isolates of the two pathogens respectively. For both pathogens the distribution of isolates amongst the different pathotypes was highly uneven. The commonest pathotype of P. graminis tritici (pathotype 343-1,2,3,5,6) comprised 50% of isolates while the commonest pathotype of P. recondita tritici (pathotype 104-2,3,6) made up 69 % of isolates. Many pathotypes of both species were represented by single isolates only.
Douglas and Tinaroo Viruses: Two Simbu Group Arboviruses Infecting Culicoides brevitarsis and Livestock in Australia
Authors: Cybinski DH
Published: July 2016

Two Australian members of the Simbu group, Douglas and Tinaroo viruses, were found to be distinct, by virus-neutralization tests, from three previously known Simbu group viruses isolated in Australia, namely Akabane, Aino and Peaton viruses. A low-titre, two-way, cross-reaction was noted between Akabane and Tinaroo viruses. Antibody to Tinaroo and Douglas viruses was detected in serum from cattle, buffalo, sheep, goats and deer but not in humans, pigs, kangaroos and wallabies. The results for horses were inconclusive. The distribution of antibodies to each virus falls mainly within the geographical distribution of the biting midge Culicoides brevitarsis, an insect from which each virus has been isolated.
Synthesis and Degradation of Aflatoxins by Aspergillus parasiticus. II. Comparative Toxicity and Mutagenicity of Aflatoxin B1 and it Autolytic Breakdown Products
Authors: L Huynh V , Gerdes RG , Lloyd AB
Published: July 2016

A crude mycelial protein extract from a 16-day-old culture of A. parasiticus, on purification, lost 50% of its ability to degrade aflatoxin B1? The addition of hydrogen peroxide increased this activity to 97% of that of the crude extract.
Effect of Human Seminal Plasma and Mouse Accessory Gland Extracts on Mouse Fertilization in vitro
Authors: Quinn P , Begley AJ
Published: July 2016

The mouse in vitro fertilization system was used to investigate the effect of human seminal plasma (HSP) on the fertilizing ability of mouse spermatozoa. The addition of HSP to freshly collected mouse epididymal spermatozoa decreased their fertilizing ability to 30%, compared with 85-90% for control spermatozoa not exposed to HSP or for spermatozoa that had been exposed to the capacitating system for 55-145 min (which allowed capacitation to occur before the addition of HSP). Human seminal plasma from a vasectomized donor was more effective in retarding the acquisition offertilizing ability in mouse spermatozoa than was seminal plasma from non-vasectomized donors. Huid from the prostate glands and seminal vesicles of mice also reduced the fertilizing ability of freshly collected mouse spermatozoa to 30%.
Development of Myometrial Electrical Activity during the First Half of Pregnancy in the Sheep
Authors: Sigger JN , Harding R , Bailey A
Published: July 2016

Uterine myoelectrical activity was recorded in seven pregnant sheep covering the period between 13 and 75 days post-coitum. Activity in the myometrium was present at day 13 and took the form of intermittent spikes of low amplitude. Bursts of spikes of irregular duration became noticeable between days 25 and 40 but most were not coordinated throughout the myometrium. Coordinated bursts of myoelectrical activity, which could be recorded at several sites simultaneously, first appeared between 40 and 65 days. These bursts had similar characteristics to the myoelectrical activity associated with uterine contractions during the last third of gestation. The myoelectrical activity showed a progressive increase in amplitude during the first half of gestation. There was no relationship between plasma progesterone levels and the increase in amplitude or appearance of coordinated bursts of uterine activity.
Amino Acid Sequence of the Globin lIB Chain of the Dimeric Haemoglobin of the Bivalve Mollusc Andara trapezia
Authors: Fisher WK , Gilbert AT , Thompson EOP
Published: July 2016

The tryptic peptides of the S-carboxymethylated globin chain ofa dimeric haemoglobin from A. trapezia were purified by high-performance liquid chromatography and their amino acid sequences determined by the dansyl-Edman method.
Deacylation Rate Constants of Acylated Human and Porcine Plasmins
Authors: B McLaren Ashley , Tanizawa Kazutaka
Published: July 2016

Deacylation rate constants, k3, were measured for the human acyl-plasmins which contain in the acyl portion, RCO, the R groups methyl, cyclohexyl, p-nitrophenyl, isobutyl, trans-isopropenyl, phenyl, a-naphthyl, anisoyl and p-guanidinophenyl. Values of k3 were also determined for the porcine acylplasm ins which have R = methyl, cyclohexyl, phenyl, anisoyl and p-guanidinophenyl. In general, for both the human and porcine acyl-plasm ins, k3 decreased as the electron-donating ability of the acyl group increased. At 25�C, the human acyl-plasmin with R = methyl has the highest k3, 1�06 � 0�05 X 10-2 S-I, and the porcine acyl-plasmin with R = p-guanidinophenyl the lowest k3, 1�4 � 0�1 X 10-6 S-I.
Total and Free Plasma Concentrations of Progesterone, Cortisol and Oestradiol-I7ß during Pregnancy, Parturition and Early Lactation in Sows
Authors: Whitely JL , Willcox DL , Newton JA , Bryant-Greenwood GD , Hartmann PE
Published: July 2016

The total (bound plus free) concentrations of progesterone, 20a-<iihydroprogesterone, oestradiol-17{:1 and cortisol were determined in the plasma of sows at three stages during pregnancy and more intensively from 5 days pre-partum to 5 days post-partum. The free fractions of progesterone, oestradiol-17{3 and cortisol were measured in the same samples by a rate dialysis method. Up to day 110 of gestation, the amounts of free hormone in plasma did not fluctuate independently of their total concentrations. During farrowing, the total and free concentrations of progesterone and cortisol varied independently of each other, whereas total and free oestradiol-17{3 declined simultaneously. The initiation of parturition was associated with a decrease in circulating total progesterone, and was accentuated by a decrease in the free fraction (P<O� 005) so that its active free concentration was only 20% of its day 1 pre-partum value. Total and free cortisol concentrations rose rapidly during labour so that at 12-18 h after birth of the first piglet 30% of that cortisol in maternal plasma was free hormone.
Studies on the Scutellar Bristles of Drosophila melanogaster. IV. Selection for Low Bristle Number in Oregon-RC Wild-type Lines
Authors: Sheldon BL , K Evans M
Published: July 2016

Results are presented of 130-145 generations of selection for low scutellar bristle number in four lines of D. melanogaster derived directly from an Oregon-RC wild-type stock and in one derived from an Oregon-RC line selected for low sternital bristle number. The most rapid initial response and the lowest mean scutellar bristle number ultimately reached, just below 2 bristles, occurred in a line in which the response was due to a new recessive gene located at approximately 17�4 on the X chromosome. Three of the other four lines reached a plateau just above a mean of 2 bristles after different patterns of response. These plateaux reflected a new canalization or threshold phenomenon at 2 bristles in these lines. The remaining line reached a mean of about 2� 5 bristles after some 50 generations and remained at that level or slightly higher thereafter, but had no indication of canalization at 2 bristles. Two relaxed lines were derived from each selection line at different times and showed variable patterns of regression towards the base population level.
Transposable Elements in Maize the?Activator-Dissociation (Ac-Ds) System
Authors: A Howard E , S Dennis E
Published: July 2016

Although unstable mutants in maize (Zea mays) were described as early as 1914 (Emerson 1914, 1917, 1929; Rhoades 1936, 1938), the first explanation of such mutants in terms of transposable DNA was provided by Barbara McClintock's elegant series of experiments on the activator-dissociation (Ac-Ds) controlling-element system of maize (McClintock 1947,1948, 1951). McClintock demonstrated genetically thatAc and Ds were short regions of DNA which could move (transpose) from one chromosomal location to another. McClintock also established that Ds could transpose only in response to the action of Ac (i.e. both elements were required in the same nucleus for Ds transposition), and that Ac could transpose autonomously (i.e. in the absence of Ds). A total of eight transposable element systems have been recognized in maize, the best characterized of which are Ac(Mp)Ds, Spm and Robertson's mutator (reviewed in Fedoroff 1983; Nevers et al. 1984). All but Robertson's mutator occur as two-element systems, similar to Ac-Ds. Transposable elements have now been shown to be widespread in living organisms-occurring in prokaryotes and lower eukaryotes as well as other higher eukaryotes, including animals.
Effect of Cadmium on the Reproductive Organs of the Male Potoroo Potorous tridactylus (Macropodidae)
Authors: L Bryant S , Rose RW
Published: July 2016

Low (2' 28 mglkg) or high (4' 56 mg/kg) doses of cadmium chloride were administered, either intraperitoneally or subcutaneously, to adult male potoroos (P. tridactylus). After 7 days, the testes, caput epididymis and spermatic cords of the high-dose groups all displayed a degree of cellular damage; however, the damage was not as extensive as that which occurs in some eutherian species after only 24 h. This time differential might be attributed to structural differences between the testicular blood supply in eutherians and marsupials.
Ovarian Response to PMSG Treatment in Ewes Immunized against Oestradiol-17ß
Authors: Boland MP , Murray JD , Hoskinson RM , Hazelton IG , Sulton R , Nancarrow CD
Published: July 2016

The effects of active immunization against oestradiol-17J3 on the ovarian response to pregnant mare serum gonadotrophin (PMSG) was investigated in Merino ewes. Immunized (79) and control (41) ewes were synchronized with intravaginal sponges, given either 750 or 1500 i.u. PMSG and then mated to rams or inseminated laparoscopically with fresh diluted semen. All control ewes mated naturally exhibited oestrus and 40 out of 41 control ewes ovulated. The ovulation rate was higher in the controls receiving 1500 i.u. PMSG than in those ewes which received 750 i.u. PMSG (10'2 v. 3'3).
Shark Myoglobins. II.Isolation, Characterization and Amino Acid Sequence of Myoglobin from Galeorhinus japonicus
Authors: Suzuki Tomohiko , Suzuki Takanobu , Yata Tohru
Published: July 2016

Native oxymyoglobin (Mb02) was isolated from red muscle of G. japonicus by chromatographic separation from metmyoglobin (metMb) on DEAE-cellulose and the amino acid sequence of the major chain was determined with the aid of sequence homology with that of G. australis. It was shown to differ in amino acid sequence from that of G. australis by 10 replacements, to be acetylated at the amino terminus and to contain glutamine at the distal (E7) residue. It was also shown to have a spectrum very similar to that of mammalian Mb02. However, the pH-dependence for the autoxidation of Mb02 was seen to be quite different from that of sperm whale (Physeter catodon) Mb02. Although the sequence homology between sperm whale and G. japonicus myoglobins is about 40%, their hydropathy profiles were very similar, indicating that they have a similar geometry in their globin folding.
Effect on Wool Growth of Thyroxine Replacement in Thyroidectomized Merino Rams
Authors: Maddocks S , Chandrasekhar Y , Setchell BP
Published: July 2016

The effect on wool growth of thyroidectomy with subsequent thyroxine replacement at subnormal and supranormallevels has been investigated in Merino rams fed a restricted basal diet. Thyroidectomy without thyroxine replacement caused a greater than 60% reduction in wool growth. Provision of 30% of normal plasma thyroxine concentrations was sufficient to return wool growth to normal. Similarly, complete replacement of plasma thyroxine levels gave normal wool growth while increasing thyroxine concentrations to three times normal increased wool growth to levels slightly above normal. These results provide a possible explanation for the inability of other workers to correlate seasonal thyroxine patterns and annual wool growth variations.
Antifertility Activity and Toxicity of a-Chlorohydrin Aromatic Ketal Analogues in Male Rats
Authors: Brown-Woodman PDC , White IG , Ridleye DD
Published: July 2016

The antifertility activity and toxicity of a-chlorohydrin and seven aromatic ketal derivatives were investigated in male rats. At a dose of 5 mg/kg injected intraperitioneally.each day for 14 days, a-chlorohydrin and the methoxy benzaldehyde derivative (compound 2) produced complete infertility. The benzaldehyde derivative (compound 1) was 89% effective and the other five compounds 71-25% effective. All compounds except the least effective antifertility agent, the methylbenzaldehyde derivative (compound 3), reduced the motility of sperm recovered from the epididymis. None of the compounds caused a decrease in body or testes weight but some increased adrenal weight.
Pattern of Loss of Spermatozoa from the Vagina of the Ewe
Authors: Tilbrook AJ , Pearce DT
Published: July 2016

In a series of experiments spermatozoa were inseminated blindly into the vaginae of ewes and then recovered at varying times after insemination. Most of the spermatozoa inseminated were lost by drainage through the vulva. The rate of loss was not affected by the motility of spermatozoa or oestrous state of the ewe. Initially after insemination the loss was not rapid with 82% of the inseminate still remaining in the vagina after 3 h. After this time losses were very rapid and by 9 h after insemination 18% of spermatozoa remained and by 12 h 10% remained. Spermatozoa� were removed from the vagina during withdrawal of the penis after intromission and the extent of this loss varied between rams and with the volume of semen already in the vagina. Up to half the inseminate was lost in this way when there was o� 5 ml of semen in the vagina but only 11 % was lost when the volume of inseminate was 0�1 ml. The unavoidable loss of spermatozoa may influence the quantity available for fertilizing ova.
Effect of Suppressing Prolactin in the Mouse on Liveweight, Food Intake and Ovulation Rate
Authors: D Brien F
Published: July 2016

The involvement, if any, of prolactin in the relationship between appetite and ovulation rate was studied in mice. Injections of 0, 50, 100 or 150 p.g of bromocryptine were given twice-daily to 46- day-old virgin mice for a minimum of 15 days. Between days 5 and 12 of treatment, mice receiving either 50, 100 or 150 p.g of bromocryptine consumed 3 '1, 4�3 and 6�2 g more food, respectively, than did mice in the control group. Liveweights and liveweight gain, however, were unaffected by bromocryptine injections. From day 0 to 12 of treatment mice grew 0,16, 0'15, 0�21 and 0�16 g/day in the 0,50, 100 and 150 p.g bromocryptine groups, respectively, (P > O' 05). Plasma prolactin concentrations were suppressed, but ovulation rates were similar in the 50, 100 and 150 p.g bromocryptine groups compared with the control (median prolactin concentrations and mean ovulation rates were 32'9, 32'5 and 31�6 ng/ml and 14'4, 15�1 and 15�7 ova, respectively, compared with 217�2 ng/ml and 14�9 ova in the control).
Monoclonal Antibodies to a Subfraction of Merino Wool High-tyrosine Proteins
Authors: Hewish DR , French PW
Published: July 2016

Monoclonal antibodies were prepared which react with members of the high-tyrosine type proteins from Merino wool. Specificity was confirmed by the use of Western transfer immunoassays and by enzyme-linked immunosorbent assay on purified fractions. Immunofluorescent staining of sections of wool follicles using the antibodies showed that the proteins were present in the developing wool shaft but that staining was asymmetric, indicating specific location of the proteins in the orthocortex of the fibres. Immunogold-electron microscopy confirmed that one of the antibodies bound to the keratin microfibril bundles.
Population Genetics of Echium plantagineum L.Target Weed for Biological Control
Authors: Burdon JJ , Brown AHD
Published: July 2016

Eight Australian and two European populations of E. plantagineum were surveyed for their genetic structure at 16 variable isozyme loci. On average, the Australian and European populations possessed 2�7 and 2�6 alleles per locus, a gene diversity of 34 and 35% and heterozygosity of 32 and 29% respectively. Estimates of the outcrossing rate in one Australian population were 61 and 73% for mean single-locus and multi-locus methods respectively. The levels of genetic diversity detected in this species consistently exceed those detected in a range of other species that occupy a similar stage in succession or that have similar breeding systems. Moreover, contrary to expectation, genetic diversity was equally great in the colonial populations in Australia as in European-source populations. If this high level of isozyme diversity reflects the diversity likely to be found in other parts of the genome, attempts to achieve substantial biological control may require the use of many different control agents.
Luteolysis and Thrombus Formation in Ovaries of Immature Superstimulated Golden Hamsters
Authors: Spanel-Borowski K , Heiss Ch
Published: July 2016

Thrombus appearance during luteolysis with and without exogenous prostaglandin (PGF2a) was studied in immature golden hamsters between days 4 and 7 after stimulation with pregnant mares' serum gonadotrophin (PMSG) followed by human chorionic gonadotrophin. Both ovaries were weighed and cut in series for light-microscopic evaluation. The fibrinolytic activity was determined by the fibrin slide .method after treatment with PGF2a on day 4 after PMSG stimulation and compared with controls of days 3 and 4 after PMSG stimulation.
Epidemiology of Bovine Ephemeral Fever in Australia 1981?1985
Authors: Uren MF , D St George T , Kirkland PD , Stranger RS , Murray MD
Published: July 2016

Bovine ephemeral fever is an important viral disease of cattle in Australia. The disease occurred each year, principally in summer and autumn, between 1981 and 1985. Queensland and the northern half of New South Wales were areas of greatest activity with only sporadic cases being reported from the Northern Territory and the northern third of Western Australia. Since 1981, the disease has been endemic in an extensive area of eastern Australia and has tended to occur in widely scattered outbreaks rather than the north-south advancing wave form of the epidemics of 1936-37, 1967-68, 1970-71 and 1972-74. The southernmost outbreaks between 1981 and 1985 were well within the limits of these earlier epidemics. The pattern of disease appears to have become seasonally endemic rather than periodically endemic in the northern two-thirds of eastern Australia. Ephemeral fever was not recorded in Victoria, Tasmania, South Australia or the southern part of Western Australia between 1981 and 1985
Electrophoretic Resolution of Species Boundaries in Australian Microchiroptera. I. Eptesicus (Chiroptera: Vespertilionidae)
Authors: Adams M , Baverstock PR , Watts CHS , Reardon T
Published: July 2016

The technique of allozyme electrophoresis is used in the present study to define species boundaries in Australian Eptesicus. Until 1976, only one species of Eptesicus (E. pumilus) was recognized in Australia. More recently, a further four species have been recognised (E. vulturnus, E. regulus, E. sagittula and E. douglasl). Results obtained from an allozyme electrophoretic analysis of 35 loci in 182 individuals show that there are a minimum of nine species of Eptesicus in Australia. Moreover, in some geographic areas, up to four species occur sympatrically. These results highlight the applicability and significance of allozyme electrophoresis for the dissection of species complexes.
Local Intra-arterial Infusion of Growth Hormone into the Mammary Glands of Sheep and Goats: Effects on Milk Yield and Composition, Plasma Hormones and Metabolites
Authors: McDowell GH , C Hart I , Kirby AC
Published: July 2016

Lactating goats and sheep were fitted with catheters in the external pudendal arteries supplying both mammary glands. Saline was infused continuously into one artery whereas the other artery received continuous infusions, over successive 4-day periods, of either saline or growth hormone (GH)-doses increasing twofold between successive periods from 100 to 400 ltg/day in goats and 400 to 3200 Itg/ day in sheep.
Effects of Pituitary-derived Bovine Growth Hormone on Production Parameters and Biokinetics of Key Metabolites in Lactating Dairy Cows at Peak and Mid-lactation
Authors: McDowell GH , Hart IC , Bines JA , Lindsay DB , Kirby AC
Published: July 2016

Changes in production parameters and metabolite biokinetics induced by treatment with pituitary-derived bovine growth hormone (bGH) were monitored at peak (c. 40 days) and mid-lactation (c. 130 days) in dairy cows.
Cycle of the Seminiferous Epithelium in the Grey-headed Fruit Bat, Pteropus poliocephalus
Authors: A McGuckin MichaeI , W Blackshaw Alan
Published: July 2016

The seminiferous epithelial cycle of wild P. poliocephalus could be divided into eight stages on the basis of cellular associations and nuclear morphology. The relative frequencies of the stages (1-8) were, respectively: 15'8,20'5,9'4,8'9,11'1,7'7,9'8, and 16�8%. The duration of the cycle was determined by intratesticular injection of [3Hlthymidine followed by autoradiography and estimated to be 16�0 days. The duration of meiotic prophase and spermiogenesis were both 23� 3 days. Spermatocyte DNA synthesis appeared to occur in leptotene primary spermatocytes in stage 2. The duration of spermatogenesis is similar to that in man although the organization of the cycle resembles that of rodents.