Atmospheric physics: atmospheric electrodynamics     

Richmond AD 《Science (New York, N.Y.)》1985,228(4699):572-573

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Ultrasonographic imaging of the temporomandibular joint in healthy cattle and pathological findings in one clinical case     

NC Borges  GE Weissengruber  J Huber 《New Zealand veterinary journal》2016,64(6):330-336

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The effect of benomyl and carbendazim on mitosis in hyphae of Botrytis cinerea Pers. ex Fr. and roots of Allium cepa L     

D.V. Richmond  A. Phillips 《Pesticide biochemistry and physiology》1975,5(4):367-379

The effects of benomyl [methyl 1 (butylcarbamoyl)-benzimidazol-2-ylcarbamate] and carbendazim (methyl benzimidazol-2-ylcarbamate) on mitosis in hyphae of Botrytis cinerea and root tips of onion (Allium cepa) were studied. The effect of the fungicides on root tips was compared with the effect produced by griseofulvin.Benomyl or carbendazim had a rapid effect on dividing hyphal nuclei. The effects of the fungicides were apparent after 5 min, and the normal stages of division were not seen clearly in any of the treated material. Chromosomes became visible at prophase-metaphase, but they did not separate completely. At the end of division, the chromatin became stretched into long threads, daughter nuclei did not separate completely, and chromatin was often present as irregular shaped masses.Benomyl and carbendazim induced abnormalities in cell division in about 3% of onion root tip cells. After treatment for 6 h, formation of the cell plate was inhibited and cells were seen with two nuclei; other aberrations produced were lagging chromosomes and anaphase bridges. After 3 days chromosomes sometimes occurred as amorphous clumps, and nuclei were found with more than two nucleoli. Griseofulvin produced similar effects in onion root tip cells, but the chromosome bridges persisted through to telophase.The results show that benomyl and carbendazim can interfere with mitosis in cells in green plants as well as in hyphae of fungi.  相似文献   

Preadsorption of boar semen with kaolin: increased efficiency of foot-and-mouth disease virus detection.     

J Y Richmond 《American journal of veterinary research》1978,39(10):1612-1616

The boar semen-associated cytotoxic factor(s), but not the antiviral activity, were removed by adsorption with kaolin. Although foot-and-mouth disease virus was efficiently removed from medium by kaolin or kieselguhr, the virus was not removed from semen-virus mixtures. Because the cytotoxicity induced by boar semen apparently altered the ability of tissue culture cells to support virus replication, preadsorption with kaolin increased the probability of detecting this virus in semen samples.  相似文献   

Severity and persistence of footrot in Merino sheep experimentally infected with a protease thermostable strain of Dichelobacter nodosus at five sites     

LJ DEPIAZZI  WD ROBERTS  CD HAWKINS  MA PALMER  DR PITMAN  NC MCQUADE  PD JELINEK  DJ DEVEREAUX  RJ RIPPON 《Australian veterinary journal》1998,76(1):32-38

Objective To test the hypothesis that ovine footrot associated with a thermostable protease strain of Dichelobacter nodosus undergoes self cure or is sustained as an annually recurring disease, depending on the environment.
Design and procedure Forty Merino sheep from a single blood line were infected with a protease thermostable strain of D nodosus a t each of five sites in Western Australia. Footrot lesions and microscopic evidence of D nodosus were recorded every fortnight for 2.5 years, supplemented by laboratory culture. Rainfall, soil and air temperature, pasture quantity and composition and soil types were also recorded. Flocks that apparently self cured were relocated to a more favourable site for footrot in the final spring season.
Results The maximum prevalence of feet with clinical footrot lesions was 80.6, 1.3, 14.4, 3.8 and 88.1% at the five sites. Severe footrot occurred for three consecutive spring seasons at one site that had clay loam soil and at least 3500 kg/ha total pasture dry matter annually. However, the infection was asymptomatic for up to 10 weeks between outbreaks. D nodosus was isolated from flocks for 2.5 years at only two sites, although there was microscopic evidence of the organism at other sites in the final year. A thermolabile variant (strain U6) of D nodosus was isolated from the two sites where footrot persisted.
Conclusion Depending on time and location, ovine footrot induced by a protease thermostable strain of D nodosus either self cured or persisted as annual outbreaks interspersed with periods of asymptomatic infection.  相似文献   

Causes of death in sheep exported live by sea     

RB RICHARDS  RT NORRIS  RH DUNLOP  NC McQUADE 《Australian veterinary journal》1989,66(2):33-38

Post-mortem examinations were conducted on 950 dead and terminally ill sheep during assembly for export and during transport by sea from Fremantle, Western Australia to various Middle East ports. Causes of death were grouped into 5 major categories; inanition (deaths associated with reduced feed intake, including hypocalcaemia and hypomagnesaemia), salmonellosis (enteric and septicaemic), trauma, diseases associated with excessive feed intake (lactic acidosis and enterotoxaemia) and miscellaneous diseases (mostly of farm origin). During assembly the causes of death were salmonellosis 53.4%, miscellaneous diseases 23.8%, trauma 12.6%, inanition 10.2%, acidosis 3.9%, enterotoxaemia 3.4% and no diagnosis was made in 3.4%. During shipping the causes of death in defined populations of sheep in 5 voyages were; inanition 43.4%, salmonellosis 20.2%, trauma 10.6%, miscellaneous diseases 5.9%, enterotoxaemia 1.0% and no diagnosis was made in 19.0%. The range of mortality rates per 10,000 sheep at risk for the first 11 days at sea in 5 voyages were inanition 52.6 to 76.7, salmonellosis 7.8 to 109.8, trauma 2.1 to 17.1, miscellaneous diseases 5.9 to 17.1 and enterotoxaemia nil to 10.3.  相似文献   

Circulating Metabolic Hormones During the Peripubertal Period and Their Association with Testicular Development in Bulls     

LFC Brito  AD Barth  NC Rawlings  RE Wilde  DH Crews Jr    PS Mir  JP Kastelic 《Reproduction in domestic animals》2007,42(5):502-508

The objective of the present study was to characterize changes in serum metabolic hormones concentrations from 20 weeks before to 20 weeks post-puberty in bulls and to investigate the associations of metabolic hormones concentrations with testicular development. Leptin concentrations increased from 16 weeks before puberty to 8 weeks post-puberty and insulin concentrations increased from puberty to 8 weeks post-puberty. Growth hormone concentrations decreased after 4 weeks post-puberty, whereas IGF-I concentrations increased from 8 weeks before puberty to 8 weeks post-puberty. During this period, testicular growth was accelerated and testosterone secretion increased substantially, without any significant changes in gonadotropin secretion. Monthly circulating concentrations of leptin, IGF-I and insulin accounted for 63% of the variation in scrotal circumference and 59% of the variation in paired testes volume. In conclusion, the secretion of metabolic hormones was not associated with changes in gonadotropins concentrations. Furthermore, the associations of leptin, IGF-I and insulin concentrations with testes size indicated that these hormones might be involved in a gonadotropin-independent mechanism regulating the testicular development in peripubertal bulls.  相似文献   

Plasma Cortisol Concentrations after CIDR Insertion in Beef Cows     

ST Long  NC Thinh  M Yusuf  T Nakao 《Reproduction in domestic animals》2011,46(1):181-184

The objective of this study was to show plasma cortisol concentration after treatment with controlled internal drug release (CIDR) in non‐suckling beef cows. On day 9 after oestrus, two cows were inserted with CIDR into the vagina for 24 h and the other two cows were treated as a control group. Four days later, the two control cows were treated with CIDR and the other two CIDR‐treated cows were used as controls. Cortisol concentrations were determined by ELISA in plasma samples collected before, during and after insertion of CIDR. There was a significant increase in plasma cortisol concentrations (p < 0.01) after insertion of CIDR. Mean (±SEM) plasma cortisol concentrations increased from 1.3 ± 0.4 to a peak of 8.8 ± 1.1 ng/ml at 5 h and then decreased to basal concentrations at 7 h after insertion of the device. In conclusion, the insertion of intra‐vaginal device causes an increase in plasma cortisol concentrations in beef cows, although the pathophysiological significance of the elevation of cortisol is not known.  相似文献   

Adrenocortical Response in Cows after Intramuscular Injection of Long‐Acting Adrenocorticotropic Hormone (Tetracosactide Acetate Zinc Suspension)     

NC Thinh  C Yoshida  ST Long  M Yusuf  T Nakao 《Reproduction in domestic animals》2011,46(2):296-300

The objectives of this study were first to show adrenocortical response to a long‐acting adrenocorticotropic hormone preparation (tetracosactide acetate zinc suspension) (ACTH‐Z) and its effect on adrenocortical function in beef cows ( Experiment 1 ) and second to apply the ACTH‐Z challenge in dairy cows based on cortisol concentrations in milk collected at routine milking ( Experiment 2 ). In Experiment 1 , four beef cows in luteal phase were challenged with ACTH‐Z, and plasma cortisol concentrations were determined for 48 h after the injection at 30‐min to 2‐h intervals. A rapid ACTH test was conducted 3 days before and 2 h after the completion of ACTH‐Z injection for 48 h to investigate the effect on adrenocortical function. Plasma cortisol concentrations increased significantly 30 min after ACTH‐Z injection (p < 0.001), and the high cortisol levels were maintained for approximately 10 h after the injection. In Experiment 2 , eight dairy cows were subjected to ACTH‐Z challenge 1–2 weeks and 4–5 weeks post‐partum. Blood and milk samples were taken at morning and afternoon milking. All the cows showed a significant increase in cortisol concentrations in plasma as well as in skim milk 8 h after ACTH‐Z injection 1–2 weeks and 4–5 weeks post‐partum (p < 0.001). There was a significant correlation between plasma and skim milk cortisol concentrations 8 h after ACTH‐Z challenge (r = 0.74, p < 0.001). The results obtained in this study suggest that elevated levels of plasma cortisol are maintained for approximately 10 h after ACTH‐Z treatment without adverse effect on adrenocortical function and a long‐acting ACTH‐Z challenge based on cortisol concentrations in milk, which were collected at the morning and the afternoon milking, can be a useful tool to monitor adrenocortical function in cows.  相似文献   

Nitrification in soil suspensions treated with chromium (III,VI) salts or tannery wastes     

Bruce R. James  Richmond J. Bartlett 《Soil biology & biochemistry》1984,16(3):293-295

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