bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Studies of a Dome Mutant and its Suppressor Gene in Schizophyllum Commune
Authors: Chang ST
Published: July 2016

A new morphological mutant of S. commune, dm.l0, was induced by trea.t-ment with ultraviolet light. It wa.s shown to be on a. linka.ge group where neither A nor B incompatibility factor is located. A wild� type sector grown out from the dome mutant colony proved to be genetica.lly controlled by a. suppressor gene, dm-l0-s, which can also a.ffect another non-allelic dome muta.nt, dm-9, but not dm-2, dm-5, and dm-7 dome-sha.ped mutants of the series. The na.ture i\nd significance of dm-l0-s and i\ possible mechanism for its operation are discussed.
The Regulation of Stomatal Aperture in Tobacco Leaf Epidermal Strips
Authors: Thomas DA
Published: July 2016

Stepwise decreases in the stomatal aperture of tobacco leaf epidermal strips followed stepwise increases in the concentration of KHCOa added to bathing solutions. Removal of KHCOa from the bathing solution resulted in a rapid increase in aperture. The reduction in aperture caused by KHCO., both in the light and dark, can be reversed by the addition of ATP or phosphoenol pyruvate to the bathing solution. The stomatal opening, supported by a NaCl bathing medium, is reduced by the addition of NaHCOa? From the results it is suggested that HCO;/C02t increases the permeability of guard cell membranes causing a net efflux of water or ions or both from the guard cells.
Ultrastructure and Differentiation of Hydrodictyon Reticulatum V. Development of Polyhedra
Authors: Marchant HJ , Pickett-heaps JD
Published: July 2016

The fine structure of mature zygospores and azygospores of H. reticulatum is briefly discussed before their differentiation to form biflagellate zoospores is described. These large zoospores are liberated through a rupture in the parental wall and after a brief period of feeble motility, retract their flagella and secrete a cell wall themselves. This wall is deposited unevenly, producing the characteristic spines of polyhedra.
Effect of Sulphate ion on the in Vitro Rumen Digestion of Polysaccharide Constituents of Bagasse
Authors: Dekker RFH , Richards GN
Published: July 2016

The dry matter digestibility (DMD) of poor quality roughages such as spear grass (Heteropogon contortus) by sheep and cattle has been shown to increase on addition of sulphur to the diet. The sulphur is added most frequently as inorganic sulphate, either alone (Playne 1969) or supplemented with urea (Bray and Hemsley 1969; Kennedy and Siebert 1972; Siebert and Kennedy 1972) or gluten (Playne 1969). These supplements have also increased feed intake in sheep (Playne 1969; Kennedy and Siebert 1972; Siebert and Kennedy 1972) and cattle (Siebert and Kennedy 1972), and have improved the nitrogen and sulphur balance (Moir, Somers, and Bray 1967; Bray and Hemsley 1969; Playne 1969; Kennedy and Siebert 1972) within the animal. Sulphates have been shown to increase the in vitro rumen digestion of starch (Kennedy, Mitchell, and Little 1971), crude fibre (Bray and Hemsley 1969), and acid-detergent fibre and cellulose (Barton, Bull, and Hemken 1971).
Histamine Levels in the Blood of Pregnant Mares
Authors: S Fernandes N , Rantilla CK
Published: July 2016

The problem of histamine metabolism has long been the subject of research. The excretion of histamine during pregnancy has been studied in cats, mice, hamsters, and many other animals, and also in human beings. However, few papers have been published on the levels of histamine in the blood of pregnant animals. In this paper the variation in blood histamine levels in pregnant mares from the first month of pregnancy until term is reported.
Studies on the Microbial Colonization of Sapwood of Pruned Apricot Trees
Authors: Price TV
Published: July 2016

The colonization by microorganisms of apricot sapwood exposed by winter pruning was investigated. The number of microorganisms isolated increased rapidly, reaching a peak 12 days after pruning unsheltered trees and 15 days after pruning trees under a rain-proof shelter.
Serological Identification of Eutypa Armeniacae
Authors: Price TV
Published: July 2016

The production of antiserum specific to E. armeniacae is described. E. armeniacae was identified by immunodiffusion tests; cross-reactions did not occur with isolates of Eutypella virescens, Eutypella parasitica, Va/seutypella tristicha, Va/sa pini, Va/sa eugeniae, Va/sa ambiens, Leucostoma cincta, Leucostoma sp., or Cytospora sp.
Action of Rec-3 on Recombination Near the Amination-I Locus of Neurospora Crassa
Authors: Smyth DR
Published: July 2016

The rec-J+ gene, which strongly reduces allelic recombination in am-I, has shown no effect on non-allelic recombination in a~ 8 map unit interval spanning am-i Allelic recombination in the gul-I locus, less than 0�3 map units distal to am-I, is also apparently not affected.
Photosynthesis and Assimilate Distribution in Lolium Multiflorum Lam. Following Differential Tiller Defoliation
Authors: Gifford RM , Marshall C
Published: July 2016

The rate of net CO2 exchange and the distribution of 14C-assimilates was studied in single plants of L. multi/lorum. Defoliation of tillers, while leaving the main shoot intact, diverted some of the 14C assimilated by leaf 10 of the main shoot to the regrowing tillers.
Response to Selection in Synthetic Lines of Drosophila Melanogaster
Authors: Howe RR , James JW
Published: July 2016

Response to selection in synthetic lines has been examined by both theoretical and experimental analyses. Synthetic lines were founded from 20 base lines of D. melanogaster all derived from the same base population and which had been selected for high sternopleural bristle number.
Aeration Pathways in Soybean Root Nodules
Authors: Bergersen FJ , Goodchild DJ
Published: July 2016

Soybean root nodule tissues contain many interconnected gas-filled intercellular spaces. They have been studied, in fresh and embedded tissue during the development and functional life of the nodules, by light and electron microscopy.
Effect of Urea on the Solubility of Bovine ,ß-Lactoglobulins
Authors: Mckenzie HA , Ralston GB
Published: July 2016

The effect of exposure of bovine ,B-Iactoglobulin to 7M urea at 25�C on its solubility in 2M ammonium sulphate-O� 5M sodium acetate-O� 22M acetic acid (PH 5�2) is examined. The solubility of the B and C variants decreases with increasing reaction time at pH 5�2, the change for B being greater than that for C.
The Application of Enzymic Hydrolysis and Tritium Labelling to a Study of the Modification of Tryptophyl Residues in Proteins
Authors: Holt LA , Milligan B
Published: July 2016

The tryptophyl residues of apomyoglobin, S-carboxymethyl-Iysozyme, and wool have been radioactively labelled in order to follow their reactions more easily. Whereas enzymic hydrolysis of these proteins gives good yields of tryptophan, it was found that enzymic hydrolysis of apomyoglobin, after either ozonolysis or treatment with o-nitrophenylsulphenyl chloride, released only part of the resultant modified tryptophyl residues.
Incorporation of [14C]Glucose and [3H]Uridine into the Major Classes of Rna in Mouse Embryos During Preimplantation Development
Authors: Murdoch RN , ales RGW
Published: July 2016

The incorporation of [U-HClglucose into the major classes of RNA in mouse embryos cultivated in vitro was studied at stages from eight-cell to the blastocyst. Comparative studies using [5-3H]uridine were also included.
Daily Changes in Stomatal Aperture and in Carbohydrates and Malate Within Epidermis and Mesophyll of leaves of Commelina Cyanea and Vicia Faba
Authors: Pearson CJ
Published: July 2016

Stomatal apertures and methanol-, water-, and hydrochloric acid-soluble carbohydrates and malate were measured in the epidermis, mesophyll, and midvein of leaves of C. cyanea R. Br. and V. [aba L. over a period of 26 hr in one experiment and over 9 hr during the photoperiod in a second experiment.
Cytokinins in Etiolated Barley Leaves
Authors: Menhenett R , Carr DJ
Published: July 2016

By the use of solvent partition, ion-exchange column chromatography, and the soybean callus bioassay, cytokinin-like substances were detected in extracts of etiolated whole leaves and leaf segments of barley, Hordeum vulgare L. cv. Pallas. The active material was retained by a cellulose phosphate column at pH 3�1 (cation exchanger) but not by a DEAE-cellulose column at about pH 6 (anion exchanger). This is consistent with the view that the active substance(s) is an N6-substituted purine derivative in the free base or nucleoside form. Preliminary attempts at characterization of the cytokinin(s) are reported.
The Role of Alternative Hosts in Survival of Phytophthora Drechsleri
Authors: Cother EJ , Griffin DM
Published: July 2016

Chlamydospores of P. drechsleri Tucker were observed in the' roots of six genera of artificially inoculated plants that are common weed species in eastern and southern Australia. Zoospore attraction to the roots of three plant species and subsequent sporulation were demonstrated. The activity of this fungus in agricultural soils is discussed.
A Growth Analysis of the Young Sorghum Root System
Authors: Hackett C
Published: July 2016

Root systems of sorghum plants grown in soil were measured at 9, 14, and 17 days from sowing. Data for 10 parameters of the root systems are reported. Notable features of the results were the low average diameter of the root members (c. O' 2 mm) and the very high mean extension rate (c. 0�8 cm per member per day), which was five to eight times higher than values reported for barley.
Erythrocyte Glutathione Level in Relation to Haemoglobin Tybe in Rajasthan Desert Sheep
Authors: D Kalla S , Ghosh PK
Published: July 2016

Concentrations of reduced glutathione (GSH) in erythrocytes were determined in 344 adult ewes of four sheep breeds (Marwari, Chokla, Jaisalmeri, and Magra) indigenous to the Rajasthan desert, India. Comparisons were made between the numbers of high GSH (GSHIl) and low GSH (GSHh) type animals and between the numbers of GSHH and GSHh animals of A, AB, and B haemoglobin type. In all, 77 % Jaisalmeri, 75 % Chokla, 67 % Marwari, and 52 % Magra animals were GSHh type. Chokla animals of both GSH types had the lowest mean erythrocyte GSH levels of all breeds tested. No effect of haemoglobin type on erythrocyte GSH level was apparent in the tested sheep of either GSH type.
Effects of Genetic Background on the Competition Between the Asc and Fm6 Chromosomes of Drosophila Melanogaster
Authors: M Mckay Charles
Published: July 2016

The asc and FM6 chromosomes of D. melanogaster were studied in competition in two differing genetic backgrounds, that of the FM6 strain and that of the combined Ore-R and FM6 strains.
Leucocyte Values in 1-6-day-old Calves of Bos indicus Crossbred and Bos taurus in a Tropical Environment
Authors: O'Kelly JC
Published: July 2016

Leucocyte counts were made on B. indicus crossbred and B. taurus calves aged 1-6 days. Calves were born in three adjacent paddocks in a tropical environment. Variations in the absolute counts of leucocyte components between animals were large and there were significant breed and age differences in lymphocyte counts. The proportions of lymphocytes increased (P<O'OI) and neutrophils decreased (P<0'05) with age. Total leucocyte, lymphocyte, monocyte and neutrophil counts were significantly higher (P< 0'001) in calves of all breeds in one paddock than in the other two.
A Histidine-3 Mutant, in Neurospora crassa, due to an Interchange
Authors: Catcheside DG , Angel Teresa
Published: July 2016

The his-3 mutant TM429, which has an absolute requirement for histidine, appears to be due to a break in the his-3+ gene just distal to the site of K874. In consequence the proximal three-quarters of the his-3 gene is separated from the distal quarter and from the cog locus, between his-3 and ad-3, at or near which most recombination in this region is initiated. The original stock of TM429 carried cog+. Allelic recombination between TM429 and his-3 genes with sites of difference proximal to TM429 is unaffected by the substitution of rec-2 for rec-2+, unless cog+ is also present in the second parent. Allelic recombination between TM429 and his-3 genes with sites of difference distal to TM429 is increased by rec-2, as also is non-allelic recombination between TM429 and ad-3, irrespective of whether cog+ or cog is in the second parent. The data are explicable if cog+ is very strongly competitive as the site for initiating recombination and if a recombination event running towards his-3 is not also established at once in the cog chromosome.
Infertility in Ewes caused by Prolonged Grazing on Oestrogenic Pastures: Oestrus, Fertilization and Cervical Mucus
Authors: Lightfoot RJ , Smith JF , Cumming IA , Marshall T , Wroth RH , Hearnshaw Helen
Published: July 2016

An experiment was conducted to investigate oestrus, fertilization and cervical mucus production in two groups of ewes, one group being of reduced fertility due to prolonged grazing on oestrogenic subterranean clover. Ewes within each of the oestrogenic (Yarloop subterranean clover) and control (Mt Barker subterranean clover) treatments were divided into subgroups of 'high' and 'low' fertility on the basis of total lambs born over the preceding 3 years.
Selected Factors that Affect the Measurement of Plasma Progesterone Concentrations in Pregnant Ewes
Authors: Gleeson AR , Thorburn GD
Published: July 2016

A competitive protein-binding technique was used to measure progesterone concentrations in the peripheral plasma of pregnant ewes. Neither haemolysis of blood nor thawing of plasma samples affected plasma progesterone concentration. Blood samples should be chilled immediately upon collection but subsequent to centrifugation immediate chilling of the plasma samples is not critical. No consistent diurnal variation in progesterone concentrations was evident but there was large apparently random day-to-day variation in progesterone concentrations for any ewe. Although a significant positive correlation was found between endogenous progesterone and corticosteroid concentrations, the present study failed to correlate experimentally elevated plasma corticosteroid concentrations with progesterone concentrations. Progesterone concentrations varied greatly between ewes at the same stage of pregnancy.
The Nature of Quantitative Genetic Variation in Drosophila. II* Average Dominance of Abdominal Bristle Polygenes
Authors: Frankham R
Published: July 2016

A comparison of 13 abdominal bristle selection lines with their base population and with reciprocal Fls between the selection lines and the base population was carried out. There was no significant directional contribution of maternally inherited factors to selection response.
A Kinetic Approach to Defining the Role of Chemically Modifiable Residues at the Active Sites of Enzymes
Authors: K Ashman Leonie , Bruce Keech D
Published: July 2016

Initial velocity studies can be used to define the function of chemically modifiable residues in the active site of a multisubstrate enzyme. Since the method relies on measuring biological activity, it has the advantage that it can be used with small amounts of relatively impure enzyme, but requires that modified enzyme molecules have some residual catalytic activity. The kinetic analysis of the modified enzyme can be carried out in the presence of some unmodified enzyme molecules.
Extra-ovarian Effects of Bovine Prolactin and Growth Hormone on the Vagina of the Mouse
Authors: Kennedy TG , Gidley-Baird AA
Published: July 2016

Hypophysectomized-ovariectomized mice receiving oestrogen and progesterone were treated with and without bovine prolactin and growth hormone (GH). Prolactin significantly increased vaginal weight and vaginal sialic acid content, but had no effect on vaginal sialic acid concentration, an indicator of vaginal mucification. Growth hormone significantly increased all three vaginal parameters. For vaginal sialic acid content and concentration, the synergism between oestrogen and progesterone was found to be greater in the presence than in the absence of GH and the maximum response to GH was obtained when between 20 and 100 Ilg GH was administered daily. It was concluded that GH but not prolactin has an extra-ovarian effect on vaginal mucification in the mouse.
Inheritance of Some Sweat Gland and Hair Follicle Characteristics in Cattle
Authors: McEwan Jenkinson D , L Mason I , Nay T
Published: July 2016

Using measurements made on cows in the herds of the Hannah Research Institute (Ayrshire), the West of Scotland Agricultural College (Ayrshire and Friesian) and in the twin herd of the Animal Breeding Research Organisation (Ayrshire), repeatability and heritability estimates were obtained for three hair follicle and four sweat gland traits. Average repeatability was high (50-70%) for all characters except angle of slope of the hair (18%). Heritability estimates were extremely variable among the different herds and methods of measurement but there was evidence of considerable genetic variation, particularly for sweat gland traits. The most consistent heritability estimate (30-45%) was given by the ratio of sweat gland length to diameter. The potential use of skin types for the selection of cattle for tropical regions is discussed.
Studies on Metatherian Sex Chromosomes I. Inheritance and Inactivation of Sex-linked Allelic Genes determining Glucose-6-phosphate Dehydrogenase Variation in Kangaroos
Authors: Johnston PG , Sharman GB
Published: July 2016

Wallaroos (Macropus robustus robustus), which have the G6PD-F electrophoretic phenotype, crossed with euros (M. r. erubescens), ofG6PD-S phenotype, produced F 1 animals which had only the maternal G6PD type regardless of the direction of the cross. When F 1 hybrids were backcrossed to wallaroos or euros, backcross progeny of either parental phenotype resulted. Sex-linked inheritance of allelic G6PD genes is shown to occur in wallaroos, euros and red kangaroos (M. rufus). Dose compensation for X chromosomes at the G6PD locus in kangaroos is achieved by inactivation of the allele of male parental origin.
Methane Production and Digestibility Measurements in the Grey Kangaroo and Sheep
Authors: Kempton TJ , Murray RM , Leng RA
Published: July 2016

Three grey kangaroos and three sheep were given a diet of lucerne chaff and measurements were made of feed intake, digestibility coefficients, methane production rate and volatile fatty acid content of the 'stomach' and caecum for each animal. The kangaroos had lower intakes of digestible dry matter and organic matter than the sheep; this was related to lower intakes of dry matter and lower apparent digestibility coefficients particularly of the crude fibre fraction. Methane production in the sheep (collected in respired air through a mask) was 0�81 Iitre/h; no methane was collected in the respired air from kangaroos. Anal release of methane in sheep and kangaroos indicated that some methane was produced in the hind gut of kangaroos and that all of this methane was lost via the anus. This finding was different to the sheep which apparently excreted 80-90 % of the hind gut methane via the lungs. Thus in both sites of apparent high microbial growth in the gut of kangaroos methane production is negligible or lower than in the same sites in sheep. Possible explanations for the absence of measurable methane production in the kangaroo forestomachs are discussed.
An Alternative Coupling Procedure for Preparing Activated Sepharose for Affinity Chromatography of Penicillinase
Authors: Coombe RG , George AM
Published: July 2016

Most applications of affinity chromatography employ the cyanogen bromide activation scheme first devised by Axtm et al. (1967). Porath and Sundberg (1972) reported an alternative procedure in which phloroglucinol and divinylsulphone are used in activating reactions. The advantages of this scheme and parameters relevant to the activating reactions are reported here. Conditions for the attachment of various ligand molecules to sepharose using a divinylsulphone activation method are defined, and a comparison with cyanogen bromide activating and coupling techniques is drawn. a-Chymotrypsin is immobilized by covalent attachment to activated sepharose. The optimum coupling pH is 8� 0-8� 6 and the reaction is virtually complete after 20 h at room temperature. Conjugates containing as much as 2 g of enzyme per gram dry weight of polymer were obtained. The immobilized enzyme retained 41 % of the free enzymic activity. An affinity column of divinylsulphone-activated methicillin-sepharose was used to demonstrate the reversible adsorption of penicillinase.
Effect of Electrical Stimulation of the Vagus Nerves on Bile Secretion in Anaesthetized Sheep
Authors: Pass MichaeI , Heath Trevor
Published: July 2016

Bile was collected before and during electrical stimulation of the vagus nerves in acute experiments on sheep with ligated cystic ducts. Most stimuli caused no change in: bile formation, but a 10-V, 10-Hz stimulus caused a slight increase in bicarbonate output. Neither the response to infused secretin nor the maximum rate of bile salt transpoit by liver cells changed during vagal stimulation; It was concluded that the vagal innervation of the liver is not likely to playa major role in the regulation of bile formation in sheep.
Kennedya Yellow Mosaic Virus: Another Tymovirus
Authors: Dale James , Gibbs Adrian
Published: July 2016

A virus has been isolated from an Australian native legume, Kennedya rubicunda. The virus, which we call Kennedya yellow mosaic virus (KYMV), is sap-transmissible to a limited number of other plant species. Purified preparations of KYMV particles contain two types of rounded isometric particles 28 nm in diameter. Particles of one type are infectious nucleoprotein with a sedimentation coefficient of 110 S and particles of the other type are non-infections protein shells with a sedimentation coefficient of 54 S. Nucleoprotein particles of KYMV contain 34 % single-stranded ribonucleic acid with a molar base content of guanine 15 %, adenine 22 %, cytosine 37 %, and uracil 25 %. The present cryptogram of KYMV is Ril : */34 : SIS: S/*.
Preparation of Metabolically Active Cell Suspensions From Wool Roots
Authors: Ward KA
Published: July 2016

A method is described for the preparation of metabolically active cell suspensions from plucked wool roots using the proteolytic enzyme trypsin. The suspensions consist of a heterogeneous population of cells which appear similar in morphology to follicle bulb cells, differentiating keratinocytes and possibly cells of the inner root sheath. The concentrations of trypsin and of inorganic ions for optimum activity of the suspensions have been determined, and the inclusion of EGTA was found to increase the yield of cells. The cell suspensions incorporate [14C]leucine, [3H]uridine and [3H]thymidine into acid-insoluble products, and are sensitive to the action of cycloheximide and emetine, but not to chloramphenicol or rifampin. Autoradiography has shown that the cells believed to be derived from the follicle bulbs show the greatest activity.
Effect of Lipid Solvents on Cutaneous Moisture Loss
Authors: Hiley PG , S Pan Y , Robertshaw D , Vercoe JE
Published: July 2016

Application of various lipid solvents and dimethyl sulphoxide to the skin of cattle, sheep, eland and African buffalo exposed to an air temperature of 20�C caused an increase in cutaneous moisture loss.
Responses of Thyroid Activity to Feed Restriction in the Goat
Authors: Abdullah Rasedee , R Falconer I
Published: July 2016

A study of the effect of restriction of feed intake on the deiodination, faecal excretion, -distribution and secretion of thyroid hormones was carried out in a group of-eight young inale goats.
Variation in the Direction of Selection Applied by Pentenol to the Alcohol Dehydrogenase Locus in Drosophila melanogaster
Authors: Oakeshott JG
Published: July 2016

This paper describes selective effects of pentenol-impregnated media on six genotypes at the alcohol dehydrogenase (Adh) locus in D. melanogaster. In the laboratory population studied, developmental times of pre-adults homozygous for an alcohol dehydrogenase 'null' allele increased with increasing pentenol concentrations. The developmental times of the other five genotypes, which produced active alcohol dehydrogenases, increased slightly at pentenol concentrations up to 0�0033%, but above this concentration they decreased markedly. In fact on 0�067% pentenol, the highest concentration tested, developmental times of these five genotypes were between 9 and 24 h less than their developmental times on media lacking penteno!. The magnitude of the reduction in developmental time differed significantly between genotypes and was positively correlated with alcohol dehydrogenase activity.
Population Cytology of the Genus Phaulacridium V. Ph. marginale ? The Omarama Population
Authors: Westerman M
Published: July 2016

During the 1975 meiotic season a sample of 105 Ph. marginale males was collected from Omarama (South Island, New Zealand). This population is polymorphic for a small metacentric B chromosome (BM) and for extra segments on the three smallest autosomes. Only 10% of males have the basic karyotype. Previous collections from this population had similar frequencies of the BM chromosomes and of the extra segments.
Proteins of the Hard Keratins of Echidna, Hedgehog, Rabbit, Ox and Man
Authors: Gillespie JM , C Marshall Robert
Published: July 2016

In the accompanying paper it has been shown that two major groups of proteins (low-sulphur and high-sulphur) of ovine wool, horn, and hoof contain similar components although the overall proportions of the groups of proteins and the relative proportions of components within the groups may show significant differences. In the present paper it has been shown for five other species (echidna, hedgehog, rabbit, ox and man) that the hard keratins produced by one animal contain the same groups of protein components but in different relative proportions. The wide apparent differences in the type and relative proportions of the low-sulphur components which comprise the major constituent proteins of the microfibrils suggest that microfibrils can tolerate a considerable variation in the constituent proteins and still produce functional structures.
Amino Acid Uptake by the Mammary Gland of the Lactating Ewe
Authors: Davis SR , Bickerstaffe R , Hart DS
Published: July 2016

(1) The arterio-venous difference technique, previously used to measure mammary substrate uptake with cows and goats, was used to measure amino acid uptake by the mammary gland of the lactating Merino ewe. Possession of a single large superficial epigastric vein by the Merino ewe makes the Merino breed the most suitable for this type of study.
The Importance of Prolactin and the Milking Stimulus in the Artificial Induction of Lactation in Cows
Authors: Peel CJ , Taylor JW , Robinson IB , McGowan AA , Hooley RD , Findlay JK
Published: July 2016

Lactations were successfully induced in 15 out of 18 non-pregnant cows treated with oestradiol-17P (0�1 mg/kg body weight) and progesterone (0�25 mg/kg body weight) on days 1-7 (where day 1 is the first day of treatment). A further 23 out of 26 cows were successfully treated with oestradiol-17 p and progesterone standardized at 40 and 100 mg/day respectively. No significant differences in milk yields were obtained by the additional treatments of twice daily milking from day 10, sustained elevation or suppression of plasma prolactin during the induction phase by reserpine and bromocryptine respectively, or by continuing oestradiol-17 p injections alone on days 8-11. Levels of plasma prolactin less than 20 ng/mI were adequate for the preparation of the mammary gland for lactation to occur. The induced lactations of 24 monozygotic twin cows ranged from 20 to 87 % of their respective siblings which had normal parturient lactations.
Testicular and Epididymal Sperm Numbers and Related Parameters in the Developing Awassi Ram
Authors: Abdou MSS , Hassun TM , El-Sawaf SA
Published: July 2016

Testicular parameters, parenchymal spermatid concentration, and epididymal sperm reserves were measured in tracts obtained from 16 Awassi rams classified into three age groups (1, 1�5 and 2�5 years old). Between 1 and 2�5 years of age the paired testis weight increased from 164�9 to 315�2 g, the testicular spermatid number (x 109 ) increased from 15�9 to 55�8, and the total epididymal sperm reserves (x 109) increased from 11�1 to 98�8.
Studies on Intravenously Infused Dexamethasone in Sheep
Authors: Leish Z , Panaretto BA
Published: July 2016

The metabolism of [1,2(n)-3Hldexamethasone intravenously infused for periods of 4 and S days was examined in four Merino wethers.
Progesterone and Corticosteroids in the Initiation of Lactation in the Sow
Authors: Martin CE , Hartmann PE , Gooneratne Anoma
Published: July 2016

The concentration of lactose in the mammary secretion from individual glands of two sows increased significantly (P < 0�01) between 0 and 24 h after parturition. In six sows studied during the perinatal period there was a negative correlation (r = - 0 .80; P < 0�02) at parturition between the concentration of progesterone in the blood and the concentration of lactose in the mammary secretion. Furthermore, the increase in concentration of lactose in the mammary secretion after parturition was related to the timing of the decline of plasma progesterone to low levels. The results indicate that the initiation of lactation occurs within 24 h of parturition in most sows, and the results are consistent with the hypothesis that progesterone withdrawal acts as the 'trigger'. Neither the changes in corticosteroid binding globulin nor the changes in total corticosteroids were temporally related to the initiation of lactation. However, a circadian rhythm was observed for total corticosteroids in the blood of three out of nine lactating and pregnant sows, whereas no circadian rhythm was observed in progesterone of the four pregnant sows. The results are discussed in relation to the disease complex mastitis-metritis-agalactia.
Transformation of Pseudomonas Aeruginosa Strain Pao With Bacteriophage and Plasmid DNA
Authors: Sinclair MI , Morgan AF
Published: July 2016

A procedure has been developed which allows transformation of P. aeruginosa strain PAD with plasmid and bacteriophage DNA at 'a frequency of 10- 6 per recipient cell. The method is similar in outline to. that developed for Escherichia coli. It involves growing the recipient cells to 3-5 x 108 per ml in nutrient broth, washing the cells with 0�1 M MgCI2 , resuspending in 0 �175 M CaC12 for 20 min, exposing to DNA for 1 h and then heat pulsing at 42�C for 1 min. Some plasmid markers are expressed immediately, whereas others require time for phenotypic expression.
Extraction and Partial Purification of Mouse Uterine Alkaline Phosphatase
Authors: Murdoch RN , Kay DJ , Capper WJ
Published: July 2016

Alkaline phosphatase in uterine homogenates from day 7 pregnant mice was solubilized using 0�2 % (v/v) Triton X-100 and extracted with 20% (v/v) n-butanol. The procedure, which resulted in 182- fold purification, included ammonium sulfate precipitation, DEAE-cellulose anion exchange chromatography and Sephadex 0200 gel filtration.
Long-Term Effects of Feeding Protected Sunflower Seed Supplement on the Composition of Body Fat in Growing Sheep
Authors: Mills SC , Searle TW , Evans R
Published: July 2016

Fifty-one Southdown crossbred and 37 Suffolk crossbred wether lambs were fed for 31 weeks a diet containing 6�6 % by weight linoleic acid derived from a formaldehyde-treated casein-sunflower seed supplement. Serial biopsy samples of subcutaneous fat were obtained during this time and over the following 49 weeks when no supplement was given. Samples of omental, perirenal and subcutaneous fat were obtained from 16 sheep slaughtered 17 weeks after supplementation ceased and the proportion of linoleic acid determined in all samples. Total body fat was estimated from tritiated water space on five occasions during supplementation.
Isolation of Inner Cell Masses From Mouse Blastocysts by Immunosurgery or Exposure to the Calcium Ionophore A23187
Authors: M Harlow Gaye , Quinn P
Published: July 2016

Two techniques have been evaluated for their use in routinely isolating inner cell masses from mouse blastocysts by destroying the trophectoderm. The most efficient method of immunosurgery was a 15-min incubation in a 1 : 50 dilution of rabbit anti-mouse spleen antiserum followed by a 30-60-min incubation in guinea pig complement (1: 10). Alternatively, inner cell masses were isolated by incubating blastocysts in 1O-5M calcium ionophore A23187 in medium devoid of calcium and magnesium ions.
Larvicidal Activity of Inhibitors of DOPA Decarboxylase on the Australian Sheep Blowfly, Lucilia Cuprina
Authors: Turnbull IF , Howells AJ
Published: July 2016

Inhibitors of DOPA decarboxylase, the key enzyme in the formation of the sclerotizing agent (N-acetyl dopamine) of the blowfly cuticle, have been tested for larvicidal activity against L. cuprina. A significant level of DOPA decarboxylase activity has been shown to be present throughout larval life in this species. Four potent in vitro inhibitors of L. cuprina larval DOPA decarboxylase (carbidopa, benserazide, methyl tyrosine and methyl DOPA) have been shown to be effective larvicides when fed to first- or second-instar larvae. However, no correlation is seen between the apparent K t and LDso values for these compounds. Treated larvae are observed to die at the next moult but death can be averted by the addition of N-acetyl dopamine to the food. Thus the toxic effects of the DOPA decarboxylase inhibitors appear to result from an inhibition of the formation of the sclerotizing agent in the cuticles of treated larvae.
Low-Iodine Diet for Producing Iodine Deficiency in Rats
Authors: McIntosh GH , Jones GB , Howard DA , Belling GB , Potter BJ , Hetzel BS
Published: July 2016

A low-iodine diet has been prepared for rats, using locally available low-iodine ingredients. On analysis it has been shown to consistently contain 15-20 ng iodine/g. When fed to growing female rats, this diet produced severe iodine deficiency while not significantly affecting growth or reproduction. The deficiency was manifested by a fall in daily urinary iodine excretion (to less than 1 JIg/day) and a seven-fold increase in thyroid uptake (1311) observable within 3 months. Levels of plasma thyroxine (T 4) and thyroid stimulating hormone (TSH) continued to change for 4-5 months, T 4 falling from 69�9 to 7�5 nmol/l and TSH increasing seven-fold from a control value of 364 to 2406 ng/ml. Goitre was present in all iodine-deficient rats and iodine content in the thyroid was 10 % of the control value.
Studies on the Apoproteins of the Major Lipoprotein of the Yolk of Hen's Eggs. IV. Aggregation in Urea of Proteins of Intermediate and High Molecular Weight and the Isolation of Four Electrophoretically Distinct Proteins
Authors: Burley RW , Sleigh RW
Published: July 2016

The gel-filtration chromatography of the total apoprotein mixture from hen's egg yolk lipoprotein in acidic 6 M urea has been re-examined using the gel-filtration materials Sephadex and cross-linked Sepharose. Electrophoresis has also been used in attempts at separating the constituents of intermediate and high molecular weight.
Sulfur and Methionine Metabolism in Sheep. IV. Metabolism and Absorption in the Intestines
Authors: Doyle PT , Moir RJ
Published: July 2016

Twelve I8-month-old Merino wethers were fed a ground and pelleted diet of equal parts oaten chaff and lucerne chaff. Sulfur flows at the ileum and faecal excretion of sulfur were estimated for two levels of dry matter intake (500 and 1000 g/day) in sheep receiving intraruminal infusions of water or 4�5 g DL-methionine per day.
Triacylglycerols and Glyceropbospbolipids in Ovaries From Maturing and Superovulated Immature Rats
Authors: Charles Tuckey Robert , Margaret Stevenson Patricia
Published: July 2016

The concentration and composition of triacylglycerols and glycerophospholipids in the rat ovary were measured during the development of follicles to corpora lutea. Changes occurring during normal development, as the rats aged from 20 to 41 days, were compared with those following treatment of 20-day-old rats with gonadotrophin to stimulate superovulation.
Effects of Heat Stress on the Lactation Performance of Ewes Accustomed to Tropical Conditions and the Total Fluid Intake of Their Lambs
Authors: Stephenson RGA , Hooley RD , Findlay JK , Hopkins PS
Published: July 2016

The impact of heat stress on the feed intake, milk production, water intake and urine output of undernourished lactating ewes and on the growth rate and water intake of their lambs was measured both in a climate chamber and during exposure to natural high ambient temperature conditions. Similar liveweight increases occurred in both stressed and unstressed lambs. Feed intake was depressed in heat-stressed ewes in the climate chamber but not under natural heat-stress conditions. During the first and second weeks of lactation calculated milk yield (200-500 mljday) and composition were unaffected by heat stress per se. However, undernutrition due to the poor quality roughage offered apparently depressed milk production of all ewes. Increased water intake (27 %) and plasma prolactin concentrations (220 %) were recorded in heat-stressed ewes, but daily urine output (27-36 mljkg body wt) was unaffected. No relationship between prolactin concentrations, milk production and antidiuretic activity was obvious. At the age of 5-6 weeks water intake accounted for 67 % (500 mljday) and 80 % (1000 mljday) of total fluid intake (water plus milk) of unstressed and heat-stressed lambs respectively. These data indicate the importance of making water freely available to lambs subjected to extensive grazing systems of tropical regions.
Estimation of Thyroid Gland Activity in the Snell Dwarf Mouse by Ultrastructural Observation of the Thyroid Gland, Measurement of Plasma Thyroxine Concentration and Thyroid Hormone Binding Capacity
Authors: Howe Effie , Howe Christopher , Pollard Irina
Published: July 2016

An ultrastructural study of the thyroid gland of the Snell dwarf mouse showed cellular activity to be very low. Follicle cell diameters were significantly lower than in controls whilst the nucleocytoplasmic ratio was significantly higher.
Multiple Haemoglobins of the Bivalve Mollusc Anadara Trapezia
Authors: Como PF , Thompson EOP
Published: July 2016

The respiratory proteins of the invertebrate marine mollusc A. trapezia have been separated by a combination of gel filtration and ion-exchange chromatography. There is a major tetrameric haemoglobin, HbI, of molecular weight approximately 67000 and two minor polymorphic haemoglobins HbIIa and HbIIb that are dimeric with molecular weight approximately 31000, in agreement with previous reports in the literature.
Amino Acid Sequence of the a-Chain of the Tetrameric Haemoglobin of the Bivalve Mollusc Anadara Trapezia
Authors: Como PF , Thompson EOP
Published: July 2016

The amino acid sequence of the IX-chain of the tetrameric haemoglobin of the bivalve mollusc A. trapezia shows 153 amino acid residues, longer than invertebrate globins previously sequenced. The amino terminal residue is acetylated as shown by nuclear magnetic resonance and mass spectrographic analysis of an N-terminal peptide. There are additional residues at the amino terminus, similar to the IX-globin of the shark and lamprey globin. In common with other invertebrate globin sequences, when compared with vertebrate globins it is necessary to insert extra gaps in interhelical regions of the vertebrate alignment to preserve homology.
Early Follicular Development and Atretic Changes in the Ovary of the Lamb? Fine Structure and Histochemistry
Authors: Tassell Robin , Kennedy JP
Published: July 2016

The fine structure of follicles was studied in ovaries from lambs up to 32 days old. Some animals received pregnant mare serum gonadotrophin prior to sampling. Follicles examined were in the primordial to early antral stages. The oocyte is described and changes associated with its development and the formation of the zona pellucida are recorded. Characteristics in which the lamb oocyte differed from those of other mammals included a greater prominence of smooth endoplasmic reticulum, the presence of microtubules, fine filaments in the peripheral parts and a large number of almost empty vacuoles. The latter were more numerous in oocytes which appeared to be degenerating, including some of those in primordial follicles. Granulosa cells had characteristics usually associated with protein secretion while some theca cells had large amounts of endoplasmic reticulum bearing few ribosomes. In early atresia changes were evident successively in the oocyte, granulosa and theca.
Liver Pathology in Mice in Poisoning by the Blue-Green Alga Microcystis Aeruginosa
Authors: R Falconer I , Jackson RB , Langley BJ , Runnegar MT
Published: July 2016

The bloom-forming M. acruginosa contains a peptide hepatotoxin. Injection of algal extracts or of solutions of purified toxin (5 x LDlOo approx.) into mice was shown to cause an increase in liver weight of 63 � 11 % within 45 min due to an increase in blood content of the organ. At the same time aspartate amino transferase and lactate dehydrogenase increased 50-fold and 20-fold respectively in serum collected by cardiac puncture. Histologically the toxin caused extensive haemorrhage in the liver with initial perilobular distribution. This was accompanied by necrosis of hepatocytes. Scanning electron microscopy showed progressive disruption of tissue structure, accumulation of erythrocytes, and loss of sinusoidal endothelium in the liver. Transmission electron microscopy confirmed that the toxin caused the breakdown of the sinusoidal endothelium and it also caused the disappearance of the space of Disse between hepatocytes and sinusoids, damage to hepatocyte membranes and necrotic changes in hepatocyte cytoplasm.
Theoretical Mechanism for Crimp
Authors: N Nagorcka B
Published: July 2016

A mechanism for crimp in wool fibres is proposed in which the inner root sheath of the wool follicle and the fibre cuticle rotate around the fibre cortex in the region just above the follicle bulb. The rotational movement of the fibre cuticle is passed on to groups of microfibrils in the cortical cells of the fibre through a gearing action, which causes them to be twisted into helices or spirals with the result that the cortical cells tend to shorten. The fibre deforms while still in the follicle causing the position of the fibre cortex near the bulb to change. This changes the magnitude and direction of the rotational movement of the inner root sheath and cuticle. A mathematical model of the mechanism is developed and several crimp forms, produced by using the model, are compared to those commonly observed.
Dexamethasone Concentrations in Plasma and Milk of Cows Following the Injection of Long- and Short-Acting Dexamethasone Esters
Authors: Fairclough RJ , Hunter JT , Welch RAS
Published: July 2016

A radioimmunoassay has been developed for the measurement of dexamethasone in plasma and milk of cows injected with long- and short-acting dexamethasone esters. Dexamethasone antiserum was produced by injecting cows with a dexamethasone-21-hemisuccinate-human serum albumin complex. The antisera was highly specific for dexamethasone, cross-reacting less than 0�7 % for all endogenous steroids tested.
Measurement of Organ Blood Flow Using Tritiated Water. I. Hind Limb Muscle Blood Flow in Conscious Ewes
Authors: Oddy VH , Brown BW , Jones AW
Published: July 2016

Blood flow rates to a hind limb preparation, consisting predominantly of muscle, were obtained with tritiated water (TOR) diffusion and radioactive microsphere techniques in four conscious ewes (a total of seven comparisons).
Amino Acid Sequences Containing Cysteine or Cystine Residues in Ovalbumin From Eggs of the Quail Coturnix Coturnix Japonica
Authors: Webster DM , Fisher WK , Koureas DD , Thompson EOP
Published: July 2016

Ovalbumin isolated from eggs of the Japanese quail, C. c. japonica, was subjected to limited proteolysis by subtilisin to give plakalbumin and then fractionated on Sephadex G75 in acid-urea to give plakalbumin S-protein and S-peptide. The plakalbumin peptide was recovered, oxidized with performic acid, and the sequence of amino acids determined from the peptides formed by enzyme digestion.
Structural Studies on the Microfibrillar Proteins of Wool: Characterization of the a-Helix-Rich Particle Produced by Chymotryptic Digestion
Authors: Woods EF , Gruen LC
Published: July 2016

The oc-helix-rich particle produced bychymotryptic digestion of the reduced and alkylated microfibrillar proteins of wool was characterized by physicochemical methods. The preparations were homogeneous with respect to size and the particle molecular weight was found to be 50200 � 2 000. Hydrodynamic methods indicated a length of about 20 nm for the particle. The properties of the particle, derived from two methods of isolation of the microfibrillar proteins, were identical and were also independent of the type of wool used.
Attraction of Drosophila Buzzatii and D. Aldrichi to Species of Yeasts Isolated From their Natural Environment. I. Laboratory Experiments
Authors: Barker JSF , Parker GJ , Toll GL , Widders PR
Published: July 2016

The attractiveness of yeast species isolated from rotting c1adodes of Opuntia inermis for adults of the cactophilic species D. buzzatii and D. aldrichi was determined by giving the flies a multiple choice of yeast species and counting the numbers on each yeast at regular intervals throughout 1 day in each of five experiments. Consistent effects implying behavioural differences between sexes, between immature and mature flies, and between the two Drosophila species were found. For immature flies of each species, there were significant differences in the numbers of flies attracted to each yeast, but preferences were more marked for females than for males.
Phenotypic Variation and Plasticity in the Colonizing Species Xanthium Strumarium L. (Noogoora Burr)
Authors: Moran GF , Marshall DR , Müller WJ
Published: July 2016

Levels of genotypic (O'G 2) and environmentally induced (O'E2) variation for 15 quantitative characters were estimated in seven populations of the four naturalized races of X. strumarium in Australia. Estimates of O'G2 indicated that populations of X. strumarium were often genetically variable for quantitative traits. However, for the majority of the characters studied, O'E2 was a larger component of the total phenotypic variation than was O'G 2 , indicating that phenotypic plasticity is the major mode of adaptation of this species to variable and varying environments. Few significant differences were found among the races, or among populations within a race, in either O'G2 or O'E2. This suggests that marked differences in colonizing ability of the four races of X. strumarium are probably not .due to differences in phenotypic plasticity (individual buffering) or genotypic variation (populational buffering) but to differences in such factors as their reproductive strategies and photoperiodic requirements for flowering.
Interpretation of the Kinetics of Consecutive Enzyme-catalysed Reactions: Studies on the Arginase-Ornithine Carbamoyltransferase System
Authors: Teasdale RD , Jeffrey PD , Kuchel PW , Nichol LW
Published: July 2016

A method that permits the use of measurements on the concentration of the intermediate in a coupled enzymic assay in determining the presence or absence of an interaction between the enzymes is presented. The method is shown to be closely analogous to a previously formulated procedure involving the determination of the rate of production of the final product of such a sequence and is shown to be applicable regardless of the complexity of the operative kinetic mechanisms, provided it may be assumed that all enzyme-substrate complexes are in the steady-state. Kinetic results obtained with the arginase--ornithine carbamoyltransferase couple, in which the intermediate ornithine is monitored, are examined in these terms to conclude that no heterogeneous association is operative between the enzymes.