bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptedness of Variants at an Alcohol Dehydrogenase Locus in Bromus mollis L. (Soft Bromegrass)
Authors: Brown ADH , Marshall DR , Munday J
Published: July 2016

Alcohol dehydrogenase is highly polymorphic in many plant and animal species. Here we report evidence that the naturally occurring, electrophoretically detectable allozyme variants of the AdhlB locus in B. mollis can respond differentially to environmental stresses. It is argued that alcohol dehydrogenase activity is specifically involved in response to these stresses. Crude extracts of predominantly selfed seeds sampled from plants of known Adh1B genotype were assayed for their ADH activity in the forward and backward reactions. The seeds from Adh~B Adh~B plants produced extracts about 12 % less active in both directions than seeds from their Adh~BAdh~B counterparts. Such Adh~BAdh~B plants were also shown to produce about 13% more dry matter when grown under continuous flooding in the greenhouse whereas no difference between genotypes was detected in control pots. The seeds of Adh~B Adh~B plants showed an advantage over the alternative homozygotes in more rapid germination at 2�C, but no difference was found at 15�C. Thus the variants are differentially adapted, and this is likely to playa role in the maintenance of the polymorphism in natural populations.
Fatty Liver and Kidney Syndrome in Chicks I. Effect of Biotin in Diet
Authors: A Pearson Judith , Johnson AR , Hood RL , Fogerty AC
Published: July 2016

Fatty liver and kidney syndrome, a disorder of young chicks, was studied under laboratory conditions. Affected chicks had enlarged livers (hepatomegaly), an increased content of lipid in the liver, and an increased level of palmitoleic acid in the liver lipids. The disorder was observed mainly in chicks from young parent flocks, and was associated either with commercial diets which were subsequently found to be low in biotin, or with specially formulated low-biotin diets. A third factor, imposition of stress, was required to initiate the disorder. There was evidence of increased lipogenesis causing an increase of triacylglycerols in the liver lipids and an increased production of saturated fatty acids, particularly palmitic acid. Increased levels of palmitoleic acid resulted from an increased desaturation of palmitic acid. Under stress, affected chicks had low blood glucose levels, suggesting that gluconeogenesis was impaired. Since biotin-dependent enzymes are involved in both gluconeogenesis and lipogenesis, it would appear that the relevant enzymes respond differently to a deficiency of biotin.
Effect of Heptane Treatment on the Response of Sarcoplasmic Reticulum Preparations to Phosphate
Authors: J Horgan Douglas
Published: July 2016

The calcium-stimulated (extra) ATPase and calcium uptake activities of sarcoplasmic reticulum (SR) preparations treated with aqueous heptane mixtures were compared with those of untreated SR, and with those of SR treated with aqueous ether. Both treatments altered the kinetic behaviour of the extra ATPase, the Lineweaver-Burk plot being changed from its normal non-linear shape to a straight line. Kinetic constants, Vma ., Km for ATP and KI for phosphate, were measured. The extra ATPase activity of heptane-treated SR was inhibited by phosphate as was that of ether-treated SR, to a lesser extent. The magnitude of this inhibition by phosphate was found to be considerably less than the degree of stimulation of the extra ATPase activity of untreated SR caused by phosphate through its calcium-precipitating action. The steady-state concentrations of the phosphoryl-enzyme intermediates were measured and together with the K m and K, values they indicate that the binding of ATP to heptane-treated SR is weaker than it is to untreated SR, and that phosphate is an efficient competitor for the binding sites.
Metabolism of Cystine by Merino Sheep Genetically Different in Wool Production IV. Rates of Entry of Cystine Into Plasma, Measured With a Single Intravenous Injection of L- [35S] Cystine, and the Subsequent Incorporation of 35S Into Wool Fibres
Authors: Williams AJ
Published: July 2016

Ten, 2-year-old Merino ewes from a flock selectively bred for high clean fleece weight (Fleece Plus) and ten from a flock bred for low clean fleece weight (Fleece Minus) were randomly divided between two dietary treatments: 600 or 1100 g/day of pelleted lucerne hay. After 14 weeks, each ewe received an intravenous injection of L-[35Sjcystine (66�4.uCi). Venous blood samples were collected at 15 specified times until 8 h after the injections, and wool fibres were plucked until 65-75 days after the injections. Protein-free filtrates prepared from blood plasma were bulked within sample times for ewes from the same flock and dietary treatment. Equations relating the specific radioactivity of free cystine isolated from the bulked filtrates to time after injection contained three exponential terms. The entry rate and pool size of cystine estimated from these equations were greater in Fleece Minus than in Fleece Plus ewes (by 25 and 44 % respectively for entry rate and pool size). Both traits were also higher in ewes offered 1100 g lucerne/day than in those offered 600 g/day (58�7 v. 33�9 mg/h for entry rate and 19�2 v. 11� 8 mg for pool size). The concentration offree cystine in plasma was greater in ewes offered 1100 g lucerne/day (3�0 v. 2�1 mg/I; P < O� 05), and greater in Fleece Minus ewes (3�0 v. 2�1 mg/I; P < 0�05).
Transfer of Sulphur to the Digestive Tract of Sheep
Authors: Kennedy PM , Hogan JP , Lindsay JR , Hogan RM
Published: July 2016

The transfer of sulphate from plasma to digestive tract and from digestive tract to plasma in crossbred sheep was estimated by the use of isotope dilution techniques with Na235S04. The passage of 35S along the digestive tract was simultaneously measured by reference to two inert radioactive markers infused intraruminally. In the first experiment, three sheep given a roughage-based diet containing 174� 7 mg S/day received an intravenous infusion of Na23SS04 for 7 days before collections were made of plasma and of digesta from the rumen, abomasum and terminal ileum. Similar collections were made in the second experiment in which four sheep received intrahuninal infusions of Na23SS04. From estimates of infusion rate of 35S, specific radioactivity of 3SS in plasma and digesta and rate of flow of sulphur in the digestive tract the following calculations were made: The transfer of sulphate from the plasma to the rumen was calculated as 29 mg S/day. Of this only 12 mg S/day passed as organic sulphur in digesta from the stomach. As the net gain of sulphur in the stomach in this experiment was 153 mg/day, sulphate transferred from the plasma contributed only a small amount of sulphur derived from endogenous sources in the stomach. In contrast, the substantial passage of 35S into the intestinal lumen during intravenous infusion of 35S04 suggested that 38 and 41 mg S/day of the 236 and 145 mg organic S/day flowing from the small and large intestine respectively was derived from plasma sulphate, corresponding to about 26 % of the dose.
Changes in Plasma Volume and Haematocrit in Intact and Splenectomized Sheep During Feeding
Authors: Dooley PC , Williams VJ
Published: July 2016

Changes in jugular haematocrit during daily 2-h feeding periods in trained sheep with and without spleens were compared with changes in the concentration of the plasma tracer radio-iodinated human serum albumin. Jugular haematocrit was increased by 16 % in intact sheep and 9 % in splenectomized sheep 20 min after they started to eat dry rations. The dilution of tracer in plasma, studied after mixing in the vascular system had been completed, showed four phases. Phase 1 was the rate of removal of tracer in the period before eating began. Phase 2 was the sudden increase in plasma radioactivity that occurred in the first 20 min of eating, indicating a loss of plasma from the circulation. Phase 3 was the decrease in tracer concentration during the remaining feeding period and phase 4 was a post-feeding phase, characterized by a slower rate of decrease of tracer than during phase 3, implying that there was significant recycling of tracer during this phase. The sudden increase in plasma radioactivity, initiated by the onset of feeding, represented a reduction in plasma volume of 10-12 %. Minimum plasma volume coincided with peak haematocrit values. The reduced plasma volume accounted for the increased haematocrit in splenectomized sheep, but only accounted for about half of the increase in intact sheep. The residual increase in haematocrit in intact sheep was most likely the result of splenic contraction.
The Regulation of Gluconeogenesis in Pouch Young of the Tammar Wallaby, Macropus eugenii (Desmarest)
Authors: A Janssens Peter , A Jenkinson Lynette , C Paton Barbara , Whitelaw Emma
Published: July 2016

Parenchymal cells have been prepared from wallaby pouch-young liver by enzymic means. Such cells exclude Trypan blue, lose little lactate dehydrogenase into the incubation medium, have an adenylate energy charge of about 0'75 and increase production of glucose from endogenous sources in the presence of 1O-9M glucagon. We conclude that the cells are metabolically viable. Hepatocytes isolated from fed pouch young released glucose in the absence of added substrates'. The rate of glucose release was increased when L-Iactate, L-Iactate+ pyruvate, propionate or fructose were added. After 24 h without food, glucose release in the absence of substrate was greatly reduced but the effect of substrate addition was greater with all substrates other than fructose.
Mating System and Hybridity in Eucalyptus pauciflora
Authors: Phillips MA , Brown AHD
Published: July 2016

Allozyme polymorphisms at four loci expressed in seeds, and three other loci expressed in seedlings, were used to determine the outcrossing rate in three natural subalpine populations of snow gum (E. paucijlora). Based on the seed loci data, an estimated 37 % of seed was derived from self-fertilization and 63 % from random outcrossing. In the most elevated population the estimate after germination was similar. However, at lower elevations the frequency of effective self-fertilization estimated at the seedling stage was only 16 %. The less elevated populations also showed a greater average heterozygosity and a larger increase in heterozygosity in the adult over the progeny stages. Heterosis apparently operated differentially in these populations-it was more intense at the lower altitudes. Selection in favour of outcrossed individuals may be an important factor in checking the spread through the population of genes which promote self-fertilization, and which would otherwise enjoy an evolutionary advantage.
Studies on Metatherian Sex Chromosomes VI. A Third State of an X-linked Gene: Partial Activity for the Paternally Derived Pgk-A Allele in Cultured Fibroblasts of Macropus giganteus and M. parryi
Authors: Cooper DW , Edwards CarmeI , James Elizabeth , Sharman GB , VandeBerg JL , A MarshalI Graves Jennifer
Published: July 2016

The locus for the glycolytic enzyme phosphoglycerate kinase A (PGK-A) is sex-linked in the eastern grey kangaroo (M. giganteus) and the pretty-face or whip tail wallaby (M. parryi). Females older than the pouch life stage of development do not express their paternally derived allele in some tissues such as blood and liver. This phenomenon is called paternal X inactivation and is characteristic of kangaroos. This distinguishes them from eutherian females, which are mosaics of two kinds of cell brought about by random X inactivation of either the paternally derived or the maternally derived X chromosome. But in skeletal and cardiac muscle the paternally derived allele is weakly expressed. This paper reports data which show that in fibroblast cells cultured from tissue explants of these two species the paternally derived allele is also weakly expressed. This suggests the possibility of a form of mosaicism as in eutherians but with unequal proportions of the two types of cell. Our results show this is not so. Cloning experiments have been performed with cultured cells from three heterozygous M. giganteus females. A total of 49 clones was obtained and each clone was like its parent culture, i.e. there was a strongly active maternally derived allozyme and a weak paternally derived one. Two interpretations of these data are possible. Each cell may have a fully active maternally derived allele and a partly active paternally derived one. Or the clones themselves may be heterogeneous, such that one or the other of the X-linked alleles may switch on or off every few cell generations or less. Since X inactivation is known to be rather stable this latter hypothesis is considered the less likely. Autoradiography shows that the longer arm of the X chromosome in the cultured cells is late-replicating. Thus later replication of the X chromosome in kangaroos does not necessarily mean complete inactivity. Differences in morphology between the two X chromosomes in females are described.
Fusion and Hybridization of Marsupial and Eutherian Cells II. Fusion of Marsupial Cells
Authors: A MarshalI Graves Jennifer , M Hope Rory
Published: July 2016

Marsupial cells could be fused using inactivated Sendai virus, and fusion frequencies were comparable to those for similar eutherian cell types. Established lines fused readily, primary diploid fibroblasts fused less well and lymphocytes fused poorly. The effects of varying the virus titre and the time of incubation of the fusion mixture were determined. The optimal conditions for fusion of marsupial cells to form homokaryons are described.
Artificial Induction of Lactation in Ewes: The Use of Prostaglandin
Authors: Fulkerson WJ , McDowell GH , Hooley RD , Fell LR
Published: July 2016

Injections of an analogue of prostaglandin F2Cl (T.F.lO!) initiated secretion of copious amounts of fluid resembling normal ovine milk when given to non-pregnant ewes with developed mammary glands. Injections of T.F.101 elicited a substantial but transient increase in the levels of prolactin in plasma. Results for intact and ovariectomized ewes were similar.
An Autoradiographic Study of the Implantation of Transferred Mouse Blastocysts
Authors: Kaye MD
Published: July 2016

Mouse blastocysts collected on day 4 were cultured in [3Hlthymidine (0�01 .uCi/ml) for 24 hand transferred to the uteri of pseudopregnant recipients. Autoradiography revealed that when such blastocysts were allowed to develop for 48 h in utero, label was apparent in the nuclei of decidual cells. The experimental conditions were physiological since blastocysts developed into normal offspring when gestation was allowed to proceed in pseudopregnant recipient animals. The transfer of foetal DNA into maternal decidual cells may be of important immunological significance.
The bipectinata Complex: A Study in Interspecific Hybridization in the Genus Drosophila (Insecta: Diptera)
Authors: R Bock Ian
Published: July 2016

Although there is no evidence of hybridization in nature, interspecific crosses in all six possible pairwise combinations may be effected in the laboratory amongst the four species of the Drosophila bipectinata complex (D. bipectinata, D. parabipectinata, D. malerkotliana and D. pseudoananassae) of the Oriental-Australian biogeographic zones. Results range from a high degree of crossability in one direction with production of large numbers of sterile male and fertile female offspring in a 1 : 1 ratio (bipectinata x parabipectinata) to almost complete isolation in both directions; in the latter case (malerkotlianaxpseudoananassae) the very small proportion of successful crosses yielded only a few females oflow viability. These results combined with those previously obtained in polytene chromosomal and electrophoretic investigations suggest very close phylogenetic relationships among bipectinata, parabipectinata and malerkotliana, with a greater degree of divergence between these species and pseudoananassae.
Dexamethasone Concentrations in Ovine Plasma During its Intravenous Infusion, its Relation to the Production of Some Endogenous Hormones, and Some of the Effects on Wool Growth
Authors: Panaretto BA , Wallace ALC
Published: July 2016

Plasma concentrations of dexamethasone have been measured in sheep during an 8-day infusion of dexamethasone-21-phosphate. The dexamethasone concentration profiles generally revealed a reproducible pattern with three phases-a peak during the first 48 h infusion which was followed by falling concentrations during the next 5 days, and a small increase in dexamethasone concentration during the final 24 h infusion was not uncommon. The pattern of dexamethasone concentrations was retained when dosage was arranged in such a way as to infuse increasing quantities of hormonal analogue as infusion progressed. Aspects of the metabolism of the analogue are discussed.
Prostaglandin F in the Fallopian Tube Secretion of the Ewe
Authors: Warnes GM , Amato F , Seamark RF
Published: July 2016

Oviducal secretions were obtained from conscious unrestrained ewes throughout the oestrous cycle via indwelling cannulae and the content of prostaglandin F (pGF) was determined by radioimmunoassay. Levels of PGF of up to 230 ngjml were found in oviducal fluids obtained from ewes showing regular patterns of secretion and normal cyclical ovarian function as indicated by plasma progesterone measurement. Relatively large day to day fluctuations in content were evident, but there was no consistent relationship between concentration and stage of the oestrous cycle. Concentrations of PGF in excess of 100 ngjml were common in preparations where autopsy later revealed infection or tissue irritation, and the concentration of PGF invariably exceeded 75 ngjml when the concentration of protein in the oviducal fluid was abnormaIly high.
Oxygen Binding of Monotreme Haemoglobins I. Oxygen Binding Parameters of the Haemoglobins of Platypus, Ornithorhynchus anatinus, and Echidna, Tachyglossus aculeatus
Authors: Hosken RW
Published: July 2016

Oxygen binding parameters have been determined for echidna and platypus haemolysates. At pH 7� 1 and 25�C platypus haemoglobin with an oxygen half-saturation pressure (Pso) of 2�4 kPa has a lower oxygen affinity than echidna haemoglobin with a Pso of 1�6 kPa. The AHo of oxygenation of platypus haemoglobin is -38�9kJ/mol which is more exothermic than the -29�7kJ/mol of echidna haemoglobin. Platypus haemoglobin has a steeper alkaline Bohr curve than echidna haemoglobin, while both haemoglobins show high levels of cooperativity at various temperatures and pH values. It appears that diphosphoglyceric acid modulates the affinity of echidna and platypus haemoglobins to different extents. This information is interpreted in terms of the steric effects of ligand binding originating in the amino acid sequence differences of these two species.
Oxygen Binding of Monotrene Haemoglobins II. Fixation of Functionally Non-equivalent Haemoglobins in the Echidna Population
Authors: Hosken RW , Boettcher B
Published: July 2016

The echidna, Tachyglossus aculeatus, has two haemoglobins and polymorphic variants of both have been described. Haemoglobins Hb-IA, Hb-IB and Hb-IIA have been separated and their oxygen binding parameters studied. Hb-IIA has a markedly higher oxygen affinity and lower cooperativity than the polymorphs ofhaemoglbin I. In phosphate buffer, pH 7�1 and 25�C, Hb-IIA has an oxygen half-saturation pressure (Pso) of 1�3 kPa and a Hill coefficient of 2�4, whereas the polymorphic forms of Hb-I have P so values of about 1�6 kPa and Hill coefficients of about 2�9. Differences in diphosphoglyceric acid interactions account for some of these differences. When the polymorphic forms of haemoglobin I were compared at pH 7 �1, Hb-IA had a AHo value of -27�9 kJjmol and a Hill coefficient of 2�9, whereas Hb-IB had a AHo value of -31�7 kJjmol and a Hill coefficient of 3�0.
Effects of Bicarbonate on the Respiration and Glycolytic Activity of Boar Spermatozoa
Authors: Murdoch RN , Davis WD
Published: July 2016

The metabolism of washed boar spermatozoa was studied in the presence and absence of low levels of bicarbonate (6 mM) and carbon dioxide (2 %). Bicarbonate stimulated the oxygen consumption of the spermatozoa but had no apparent effect on glycolysis. The stimulatory effect of bicarbonate on respiration depended on the presence of a utilizable exogenous energy source such as glucose, fructose, lactate, or pyruvate and no stimulation occurred when no substrate was added or when acetate was used as substrate. The response of the spermatozoa to bicarbonate also depended on the presence of adequate concentrations of potassium (5 mM) and to a lesser extent magnesium (1 mM).
Studies on Metatherian Sex Chromosomes VIII. Evidence for an Absence of Dosage Compensation at the Glucose-6-phosphate Dehydrogenase Locus in Cultured Cells of Macropus rufogriseus
Authors: A Raphael Kathie , Cooper DW
Published: July 2016

The level of the sex-linked enzyme glucose-6-phosphate dehydrogenase (G6PD) has been measured in cultured fibroblasts of M. rufogriseus and several other kangaroo species. The data obtained support the conclusion obtained from other evidence that there is a failure of dosage compensation at this locus in fibroblasts of females.
Fusion and Hybridization of Marsupial and Eutherian Cells VI. Hybridization
Authors: M Hope Rory , A MarshalI Graves Jennifer
Published: July 2016

We have fused many different combinations of marsupial and eutherian cells, in order to test their capacity to form proliferating marsupial x eutherian somatic cell hybrids. During the first week after fusion we were able to identify marsupial x eutherian synkaryons, a number of which had undergone extensive chromosome fragmentation. For some combinations of marsupial and eutherian cells one parental cell type could not be completely eliminated from the fused cultures by the various selective systems employed, making it difficult to distinguish possible hybrid cells from parental cells. However, many hybridizations yielded discrete colonies which could be isolated and further studied. The first hybrids to be confirmed were produced from fusions between Pseudocheirus peregrinus (Marsupialia) lymphocytes and cultured mouse cells from the line PG19. These hybrid cells possessed clearly identifiable marsupial and mouse chromosomes and enzyme markers. Certain other combinations of marsupial and eutherian cells yielded 'eutherian-like' colonies. Although initially slow growing, these cells came to resemble the eutherian parental cell type in morphology, growth rate and cloning efficiency. Some of these colonies were shown to be composed of variant eutherian cells. However, others were clearly marsupial x eutherian hybrids as they possessed enzyme markers of each parental cell type even although, in some cases, these cells possessed no identifiable marsupial chromosomes. All the marsupial x eutherian hybrids isolated showed either partial or complete loss of marsupial chromosomes. We discuss the difficulties associated with the derivation of marsupial x eutherian hybrids, the important features of these hybrids, and their potential use for further studies.
Lipid Content of Sheep Ovarian Follicles in Culture
Authors: Hamilton RP , Seamark RF
Published: July 2016

A detailed examination was made of the lipid content of sheep ovarian follicles maintained in organ culture, and of the effect on this of human chorionic gonadotrophin.
Response to Partial Selection on Clean Fleece Weight in South Australian Strong-Wool Merino Sheep III. Genetic Distance Between Flocks
Authors: Mann TLJ , Mayo O
Published: July 2016

Divergence over time in flocks selected for clean fleece weight and for fecundity is measured by gene frequency changes at the R-r-i blood group, haemoglobin, and transferrin loci. No unequivocal effect of selection is demonstrable. Problems of interpretation even in flocks of known history are discussed.
Post-Mortem Electrical Stimulation of Muscle and its Effects on Sarcoplasmic Reticulum Adenosine Triphosphatase
Authors: K Tume Ronald
Published: July 2016

Sarcoplasmic reticulum (SR) was isolated from control muscles and from muscles which had been subjected to short-term post-mortem electrical stimulation. Both preparations had similar protein compositions but the SR from electrically stimulated muscle had a lower 'extra' ATPase activity. The ability of the SR preparations from electrically stimulated muscles to accumulate Ca2+ was about the same as the controls. There was, therefore, an apparently greater efficiency of Ca2+ transport in the isolated vesicles, the reason for which is not known, but an alteration in the 'leakiness' of the membrane may be involved. Purified ATPase isolated from control and stimulated SR contained, in addition to the ATPase protein, a polypeptide of molecular weight about 30000. The purified ATPase vesicles from electrically stimulated muscle had a reduced activity as measured by ATP splitting activity, phosphoenzyme formation from either inorganic orthophosphate (Pi) or ATP, or by an ATP � Pi exchange reaction. These reduced activities probably result from an alteration in the binding affinities of the ATPase for ATP and Pi' The low affinity site for calcium binding was not affected by electrical stimulation. Purified ATPase vesicles from stimulated muscle were more susceptible to proteolytic attack, suggesting that the conformation of the protein or its association with the membrane lipids had been altered.
The Use of Oestrogen, Progesterone and Reserpine in the Artificial Induction of Lactation in Cattle
Authors: Peel CJ , Taylor JW , Robinson IB , Hooley RD
Published: July 2016

Oestradiol-17 p, progesterone and reserpine were utilized in three experiments in an attempt to improve the success rate and the magnitude of hormonally induced lactations. Onset of lactogenesis induced by steroid administration was measured by a surge in the lactose content of the mammary secretion and lactations were regarded as being successfully induced if milk yields exceeded 3 kg/day. In all experiments, the dose rate of oestradiol-17 p was standardized at the reduced level of 20 mg/day (approximately 0�05 mg/kg body weight daily), and progesterone maintained at 100 mg/day (approximately 0�25 mg/kg body weight daily) for the initial 7 days (days 1-7). The halving of the dose rate of oestradiol-17 p from the commonly used 0�1 mg/kg body weight daily eliminated the occurrence of noticeable physical injuries in the 60 animals so treated.
Relationship Between Protein Synthesis and Secretion in Liver Cells and the State of the Adenine Nucleotide System
Authors: Edwards Kaylene , Urban Jörg , Schreiber Gerhard
Published: July 2016

Adenine nucleotide levels could be precisely and reproducibly adjusted in liver cell suspensions by partially depleting the ATP pool with D-fructose or glycerol. Thus, it was possible to quantitatively correlate rates of protein synthesis and secretion with intracellular levels of ATP and with derived parameters, such as the adenylate energy charge. Half the maximum rate of incorporation of leucine into protein was observed at an energy charge of 0�80, a ratio of ATP to ADP of 2�6, and an ATP level of 1�05 pmol per g of wet cells. Proteins were secreted with half the maximum rate at an energy charge of 0�85, a ratio of ATP to ADP of 3�1 and an ATP concentration of 1 �1 pmol per gof wet cells. Protein secretion dill not depend on continued synthesis. Inhibitors of oxidative phosphorylation inhibited protein secretion in addition to protein synthesis, in contrast to observations by other authors on liver slices.
Tumour Incidence, Growth, Reproduction and Longevity in Female C3H Mice Fed Polyunsaturated Ruminant-Derived Foodstuffs
Authors: R Pennycuik Pamela , Fogerty AC , E Willcox Mary , C Ferris Margot , Baxter RI , Johnson AR
Published: July 2016

Earlier studies with the random-bred Quackenbush mouse strain showed that human-type diets based on linoleic acid-enriched foodstuffs derived from ruminants fed protected polyunsaturated oils have no detrimental effects on growth, reproduction or longevity. Tumour incidence and time of onset of tumour development have now been studied in the inbred, tumour-prone mouse strain C3H, in addition to growth, reproduction and longevity. Mice were fed a polyunsaturated human diet, a conventional human diet, or mouse cubes.
Foetal and Placental Growth in the Mouse After Pre-implantation Development in Vitro Under Oxygen Concentrations' of 5 and 20%
Authors: M Harlow Gaye , Quinn P
Published: July 2016

Blastocysts which developed from two-cell mouse embryos in culture tubes containing an atmosphere with 20 % oxygen had approximately 20 % fewer blastomeres than blastocysts which developed under an oxygen concentration of 5 %. When these smaller blastocysts were transferred to the uteri of pseudopregnant foster mothers, the foetuses developing were as viable as those developing from blastocysts cultured under 5 % oxygen, indicating their ability to regulate for a lower blastomere number by at least day 17 of development.
Haemoglobin Oxidation in Whole Blood Samples From Sheep in Relation to Glutathione Peroxidase Activity
Authors: Wilkins JF
Published: July 2016

A high correlation was observed between HzOz-induced oxidation of haemoglobin and glutathione peroxidase activity in whole blood samples from sheep. A role of this enzyme in the prevention of oxidative damage to the erythrocyte and its contents has been previously demonstrated. The possibility of using haemoglobin oxidation in whole blood as an alternative assessment of glutathione peroxidase activity and hence of selenium status is proposed.
Pituitary Response of Prepuberal Lambs to Oestradiol-17ß
Authors: T Tran Chu , Edey TN , Findlay JK
Published: July 2016

In two experiments 48 prepuberal Merino ewe lambs were injected with oestradiol-17P (E2) or saline to study the effect of E2 on their plasma LH levels and on oestrus and ovulation. In the three groups which received 30 (experiment I), 50 and 30 (experiment II) p,g E2 respectively, 27 out of 28 lambs showed an LH response, the corresponding mean LH peaks being 64�3�22�5, 153�6�33�4 and 91�7�16�9ng/mi at mean intervals of 11�1,11�2 and 10�5h, respectively, after injection. None of the 20 lambs in the control groups had an LH level higher than 18 ng/ml12 h after injection. In the three E2 groups, 41�7, 62�5 and 37�5 % of animals showed oestrus within 26 h of injection while in the control groups only one animal showed oestrus. Of 13 animals showing oestrus in the E2 groups, 11 failed to ovulate. The mean pre-injection plasma FSH level in experiment I was 102�7 ng/mI, and in four 5-7-month-old lambs over several weeks was 155�3 ng/mi. Despite these high pre-injection levels of FSH, it appears that the follicles were unable to respond to the LH peak which followed the E2 injection.
Frequency-Dependent Models for X-linked Loci in Kangaroos
Authors: Crozier RH , Parnilo P
Published: July 2016

In kangaroos, the paternal X-chromosome is genetically inactivated, so that there is not a perfect correspondence between phenotype and genotype frequencies. Following the demonstration by Cooper in 1976 that constant fitnesses are much less likely to lead to balanced polymorphisms under this type of inheritance than under autosomal or ordinary sex-linkage, we examined the situation with regard to frequency dependency under simple exponential and arithmetic fitness function models. Except for the case of exponential fitness functions operating in females only, which results in allele frequency cycles of neutral stability, all cases examined yield single stable equilibrium points. Addition of a constant to the fitness functions converts the cyclic case to one with a single stable equilibrium point and results in a slower approach to equilibrium in the other cases.
Serum Prolactin .and Brain and Pituitary Monoamine Responses to Chronic Monoamine Oxidase Inhibition in the Rat
Authors: Smythe GA , Brandstater JF
Published: July 2016

The acute administration of the monoamine oxidase inhibitor iproniazid to rats causes a highly significant suppression of serum prolactin levels at 2 h. At the same time there is a significant rise in the hypothalamic-median eminence concentrations of the biogenic monoamines dopamine, noradrenaline and serotonin. When iproniazid is administered daily to rats for 4 days and the animals are examined on the fifth day brain noradrenaline and serotonin levels are elevated similarly to those seen after acute administration but dopamine concentration is near normal while serum prolactin is significantly elevated. This study thus demonstrates that a quite specific and unexpected change occurs in the regulation of hypothalamic-median eminence dopamine when iproniazid is administered chronically and provides an explanation of previous observations in human subjects where raised serum prolactin levels are observed after chronic therapy with monoamine oxidase inhibitors.
Effects of Genotype and Light on Mating Preference in Drosophila Melanogaster
Authors: Oakeshott JG , Hayman DL
Published: July 2016

Patterns of mating have been investigated among yellow-bodied and white-eyed D. melanogaster. The relative mating success of yellow-bodied and white-eyed males was found to depend on both the light/dark regime and the phenotype of the female receiving them. White-eyed males were more likely to succeed in the dark 01' with white-eyed females. The effect of the light/dark regime probably reflected the visual defect in white-eyed males and the effect of the female phenotype was primarily due to strong avoidance of yellow-bodied males by white-eyed females. The overall pattern of mating indicated environment-dependent sexual selection and suggested several models for the experimental analysis of the relations between environmental and genetic variability. Possible implications for wild populations are also discussed.
Properties and Function of Fumarate Reductase (NADH) in Streptococcus Lactis
Authors: Hillier AJ , Jericho RE , Green SM , Jago GR
Published: July 2016

The fumarate reductase (NADH) present in cell-free extracts of S. lactis CIO was purified approximately 100-fold by chromatography on DEAE-cellulose in the presence of the non-ionic detergent Teric X-lO, and some of the properties of this partially purified enzyme were characterized. Fumarate was able to act as a terminal electron acceptor and decreased the amount of lactate formed and oxygen used during the metabolism of pyruvate by resting cells of S. lactis. Anaerobic growth of S. lactis on glycerol was not observed and fumarate reduction was not coupled with glycerol-3- phosphate oxidation.
Pathways of Energy Metabolism Required for Phenotypic Expression of Nif+Kp Genes in Escherichia Coli
Authors: L Skotnicki Mary , G Rolfe Barry
Published: July 2016

In E. coli K12 (F'nif+ KP) hybrids, electron-transport-dependent phosphorylation is not necessary for anaerobic nitrogen fixation, and substrate level phosphorylation can provide sufficient ATP from glucose for nitrogenase activity, The fumarate-reduction system, however, is essential in these hybrids for the transfer of electrons to nitrogenase, This system is probably also involved in maintaining the membrane in the energized state, thereby allowing nitrogen fixation to occur
Changes in the Matrix Proteins of Wool and Mouse Hair Following the Administration of Depilatory Compounds
Authors: Gillespie JM , Frenkel MJ , Reis PJ
Published: July 2016

After sheep were defieeced with mimosine, cyclophosphamide or N-[5-(4-aminophenoxy)pentyl]phthalimide, the first samples of the new growth of wool differed markedly in composition from the pretreatment samples, there being substantial reductions in the high-tyrosine proteins and increases in the high-sulfur proteins. Similar results were obtained with mice dehaired with mimosine and with sheep treated with low levels of mimosine which resulted in weakened wool rather than depilation. The composition of later samples of the regrowth wool showed progressive changes with time. The high-tyrosine proteins tended to approach the pretreatment levels, although this may take up to 12 weeks to occur, whereas the levels of high-sulfur proteins, after the initial increase, often fell below normal. In experiments involving defieecing with cyclophosphamide, the level of the latter proteins was still below normal after 3 months.
Myoglobins of Cartilaginous Fishes. II. Isolation and Amino Acid Sequence of Myoglobin of the Shark Mustelus Antarcticus
Authors: Fisher WK , Koureas DD , Thompson EOP
Published: July 2016

Myoglobin isolated from red muscle of the gummy shark M. antarcticus was purified by gel filtration and ion-exchange chromatography on carboxymethyl cellulose in 8 M urea-thiol buffer. Amino acid analysis and sequence determination showed 148 amino acid residues. The amino terminal residue is acetylated as shown by nuclear magnetic resonance and mass spectrographic analysis of an N-terminal peptide. There is a deletion of four residues at the amino terminal end as well as one residue in the CD interhelical area relative to other myoglobins. These overall differences were also found previously in myoglobin of Heterodontus portusjacksoni.
Effects of Grafting the Skin in Merino Sheep, With Special Reference to the Growth of Wool and Hair
Authors: Lyne AG , Hollis DE
Published: July 2016

Grafts of wool-growing trunk skin (wool grafts) and hair-growing inguinal skin (hair grafts) were studied in two black and two black and white adult Merino sheep. Skin growing black wool was transplanted to skin growing white wool and vice versa. Also, skin in both black and white regions was excised and returned to the same site. Inguinal skin was transplanted to black wool-growing skin.
Degradation of Nucleic Acid by Allomyces macrogynus during the Production of Zoosporangia and Resistant Sporangia
Authors: Youatt Jean
Published: July 2016

Allomyces macrogynus plants were induced to make either zoosporangia in distilled water or resistant sporangia in a solution of glucose and glutamic acid. Analyses during the stages of developmentJ showed that plants of both series degraded nucleic acid, releasing uracil, hypoxanthine and guanin~ to the suspending medium. Plants in distilled water released inorganic phosphate to the medium while those in glucose-glutamic acid solution conserved the phosphate as bound phosphate. A. arbuscula also released the purines and pyrimidines.
Immunological Functions of the Mammary Gland and Its Secretion-Comparative Review
Authors: Watson DL
Published: July 2016

The mammary gland performs vitally important immunological roles, both in providing passive immune protection to the suckling infant and in immunological defence of its own tissues against infection with microorganisms. These immunological functions differ greatly between species of mammals in both nature and magnitude. In ungulates the mammary gland is singularly responsible for transfer of immunoglobulin (IgG) from mother to young. This process is dependent on a highly selective mechanism which results in the transport of blood-borne IgG molecules across secretory epithelial cells of the colostrum-forming mammary gland and into secretion. Upon ingestion of colostrum by the young ungulate this immunoglobulin is absorbed across the wall of the small intestine and thence into the bloodstream.
Effects of Somatostatin and Glucagon on the Utilization of [2_14C] Propionate in Glucose Production in Vivo in Sheep
Authors: P Brockman Ronald , Greer Cindy
Published: July 2016

This study examined the effects of hypoglucagonaemia and hyperglucagonaemia on the incorporation of 14C from [2-14C]propionate into plasma glucose of sheep in vivo. The sheep were adult ewes fed a maintenance diet of lucerne pellets delivered in equal aliquots hourly. The irreversible loss of glucose was determined by the continuous infusion of [6-3H]glucose. During the control period (the hour immediately preceding infusion of hormones) 63 �2 % of the propionate was converted to glucose, accounting for 30�2 % of glucose production. Glucagon deficiency, induced by infusion of somatostatin (100 J1g/h), did not affect gluconeogenesis and the irreversible loss of glucose significantly. However, glucagon infusion at 11 �5 �O� 6 J1g/h significantly increased the irreversible loss of glucose, with the greatest increase occurring in the first 15 min of infusion. The 14C specific radioactivity of glucose and the fraction of glucose derived from propionate decreased significantly during glucagon infusion. The data are consistent with glucagon having a marked glycogenolytic effect initially, but little or no selective effect in promoting the utilization of propionate for glucose synthesis in vivo in sheep.
Amino Acid Sequences Containing Cysteine or Half-Cystine Residues in ß-Glucuronidase
Authors: Leighton PH , Fisher WK , Moon KE , Thompson EOP
Published: July 2016

Amino acid analysis of oxidized or reduced and carboxymethylated p-glucuronidase have shown the presence of 24 cysteic acid or S-carboxymethylcysteine residues respectively per mole of the tetrameric enzyme. Titration of sulfhydryl groups gave eight cysteine residues, and by difference 16 half-cystine residues per mole.
Properties of Mouse Inner Cell Masses Isolated by Immunosurgery, Exposure to the Calcium Ionophore A23187 or Low Osmolarity
Authors: Harlow GM , Quinn P
Published: July 2016

Mouse inner cell masses remained intact when exposed to extreme bsmotic stress (distilled water) for short periods, but the trophectoderm was lysed in one-third of blastocysts. However, these inner cell masses were not viable as they could not fluoresce after incubation in fluorescein diacetate nor continue development in vitro. It was concluded that cells of the inner cell mass are not more tolerant of osmotic stresses than those of the trophectoderm.
Sulfate Uptake and Somatomedin Levels in the 'Little' (lit/lit) Mouse
Authors: M McKern NeiI , B Cheek Donald , Crewther WGordon
Published: July 2016

The mutant 'little' (lit/lit) mouse is deficient in growth hormone and has correspondingly low levels of serum somatomedin. Injection of these mice with human or bovine growth hormone significantly r(l.ises serum somatomedin levels within 6 h. In vivo uptake of radioactive sulfate by costal cartilage in lit/lit mice is similar to that of normal mice, which is unexpected in view of the low levels of circulating somatomedin. If costal cartilages from normal and lit/lit mice are preincubated in medium 199 in vitro before transfer to fresh medium containing radioactive sulfate and serum, there is no consistent difference in uptake of sulfate, demonstrating similar endogenous cartilage activity. In contrast, omission of the preincubation step reveals a lower uptake of sulfate in vitro by cartilage from lit/lit mice as compared with normal mice. Cartilage removed from lit/lit mice 24 h after injection with growth hormone, however, takes up greater amounts of sulfate than cartilage from untreated normal mice.
Inheritance and Expression of Two Peptidases in the Wallaroo, Macropus rohustus (Gould)
Authors: Briscoe DA , Murray JD , Sharman GB
Published: July 2016

The formal genetics of two peptidase loci in M. robustus are presented. Both loci are autosomal but do not appear to be located on the same chromosome pair. Alleles at both loci are codominantly expressed in neonates, pouch young and adults. The application of autosomal loci segregating for three or more alleles in studies of embryonic gene expression is discussed.
Enzymes of Galactose Metabolism in Livers of Suckling and Adult Tammar Wallabies (Macro Pus Eugenii) and Other Marsupials
Authors: K Vernon Jennifer , Messer MichaeI , Green Brian
Published: July 2016

The activities of galactokinase, hexose-I-phosphate uridylyl transferase and UDPglucose 4-epimerase in homogenates of livers of two adult and 20 suckling tammar wallabies aged from 6 to 50 weeks were investigated. The activities of all three enzymes were high until 24-30 weeks post partum, after which they declined to low levels.
Iodine Deficiency and Brain Development in the Rat
Authors: McIntosh GH , Howard DA , Mano MT , Wellby AML , Hetzel BS
Published: July 2016

An assessment was made of the influence of low-iodine diet on somatic and brain development at birth (day 0) and 21 days postnatally in the rat. The rat mothers were proven to be iodine-deficient by assay of plasma thyroxine and thyroid stimulating hormone prior to mating, and at 21 days postnatally, when maternal thyroids were removed, weighed and stored for subsequent iodine analysis, along with those of the offspring. There were no significant differences in body weight or brain weight of the offspring at birth, or in the content of DNA or protein. However, at 21 days there was a significant reduction in body weight (21 �7%) and whole brain weight (7�9 %, P < 0�02) which was associated with a significant fall in cholesterol content (12�4 %, P < 0�05) and protein level (9�6%, P < 0�01), while DNA was not significantly affected (6%). The greatest reduction in weight was seen in the cerebellum. The thyroids in these rats were double normal size, showed follicular cell hypertrophy and absence of colloid histologically, and contained 8 % of the iodine content of controls.
Control of Gluconeogenesis in the Lactating Sheep
Authors: Gow CB , McDowell GH , Annison EF
Published: July 2016

Ewes which had been lactating for 3-4 weeks and which had been milked by hand from the day of parturition were subjected to food restriction for 4 days. One group of three ewes was fed ad libitum and a second group of four ewes was fed to meet calculated requirements for maintenance and milk production. Over 4 days food intake was reduced by 80 % in both groups of ewes.
Modulation of Functional Capacity of Small Ovarian Follicles in the Post-partum Cow by Prolactin
Authors: Weiss TJ , Nancarrow CD , Armstrong DT , Donnelly JB
Published: July 2016

This study was undertaken to examine the possibility that the prolonged anovulatory period frequently experienced by the post-partum cow is due to a disruption of function at the ovarian level promoted by the high, suckling-induced, blood prolactin concentrations. Fifteen cows, less than 35 days post partum, were allocated to three groups (1, 3 and 5) and given no hormonal treatment, prostaglandin plus pregnant mare serum gonadotrophin (PMSG) treatment or injected with 2-bromo-ex-ergocryptine to reduce circulating prolactin levels.
Effects of Somatostatin and Adrenergic Blockade on Glucagon, Insulin and Glucose in Exercising Sheep
Authors: P Brockman Ronald , Halvorson Roseanne
Published: July 2016

This study was conducted to characterize the mechanisms of hyperglycaemia in exercising sheep. Sheep were run on a treadmill for 45 min (5�5 km h- 1 , 8 % incline) during adrenergic blockade (propranolol or phentolamine mesylate infusions) and during suppression of the rise in glucagon by infusion of somatostatin (SRIF). Propranolol did not alter the glucagon, insulin or glucose responses, except it tended to increase the metabolic clearance of glucose, presumably as a result of blocking the p-adrenergic inhibition of glucose uptake.
Detection of Human Spermatozoal Peptides After Conjugation to 125J-Labelled Human Serum Albumin
Authors: Mettler L , Skrabei H , Czuppon AB
Published: July 2016

Human spermatozoal peptides, liberated during autolysis of the cells, were fractionated by gelfiltration chromatography and thin-layer chromatography. After conjugation to 125I-labeIIed human serum albumin, all fractions were assayed with rabbit antihuman spermatozoa antiserum. The reactions indicated the presence of a number of antigenic peptides in the spermatozoal autolysate and one of the fractions revealed a significantly higher antibody binding capacity than all other fractions assayed (P < 0�05). Release of immunogenic peptides during autolysis of the spermatozoal membrane could be important in the aetiology of spermatozoal iso- and autoantibodies.