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Bulletin 4474 - Exotic Diseases - Horses, Agriculture Western Australia

Bulletins 4000 -

An exotic disease is a disease that is not present in Australia.

If an exotic disease did occur in Australia it would cause production losses, stock deaths and stop exports of primary production. When export markets are lost they can only be re-established once it is proven the disease is eradicated.

Re-Thinking The Summer Drenching Program, Brown Besier

Journal of the Department of Agriculture, Western Australia, Series 4

The summer drenching program has provided highly effective sheep worm control in Western Australia for many years - but recent research challenges its long term sustainability.

Trial results suggest that in large parts of the State, summer drenching is the main factor leading to the development of drench resistant worms. Alternative programs less likely to lead to drench resistance will require greater monitoring of worm burdens and panning pasture moves.

Clenbuterol In The Horse: Confirmation And Quantitation Of Serum Clenbuterol By Lc-Ms-Ms After Oral And Intratracheal Administration, A. F. Lehner, J Daniel Harkins, W. Karpiesiuk, W. E. Woods, N. E. Robinson, L. Dirikolu, M. Fisher, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Clenbuterol is a β₂ agonist/antagonist bronchodilator, and its identification in post-race samples may lead to sanctions. The objective of this study was to develop a specific and highly sensitive serum quantitation method for clenbuterol that would allow effective regulatory control of this agent in horses. Therefore, clenbuterol-d₉ was synthesized for use as an internal standard, an automated solid-phase extraction method was developed, and both were used in conjunction with a multiple reaction monitoring liquid chromatography-tandem mass spectrometry (LC-MS-MS) method to allow unequivocal identification and quantitation of clenbuterol in 2 mL of serum at concentrations as low as 10 …

Equine Laminitis Reviewed, Jocelyn Nelson

Undergraduate Honors Capstone Projects

Laminitis, also known as founder, is one of the most devastating and crippling conditions affecting horses throughout the world today. Traditionally defined as the inflammation of the laminae within the hoof, laminitis actually presents itself as a complicated, multi-system disease, that, through a series of interrelated events, leads to a characteristic lameness. This lameness has serious economic and humane consequences because affected horses are often seen in pain, and frequently must be destroyed due to permanent damages within the hoof.

Effect Of Amitraz And Xylazine On Some Physiological Variables Of Horses, A. Queiroz-Neto, A. B. Carregaro, G. Zamur, J Daniel Harkins, Thomas Tobin, M. I. Mataqueiro, S. C. Gonçalves

Maxwell H. Gluck Equine Research Center Faculty Publications

The effect of the intravenous injection of amitraz (0.1 mg/kg) to horses on cardiac activity, respiratory rate, intestinal motor activity, rectal temperature, sweating and masticating was evaluated and compared to the effect of intravenous administration of xylazine (1mg/kg, iv) on heart rate, respiratory rate and intestinal activity. Amitraz caused a significant decrease in heart activity, respiratory rate and intestinal movements, but these effects were not as pronounced as those caused by xylazine. Amitraz also caused a significant relaxation of the rectal smooth muscle, and an apparent increase in sweating and in the frequency of horses found masticating hay. Rectal temperature …

Remifentanil In The Horse: Identification And Detection Of Its Major Urinary Metabolite, A. F. Lehner, P. Almeida, J. Jacobs, J Daniel Harkins, W. Karpiesiuk, W. E. Woods, L. Dirikolu, Jeffrey M Bosken, W. G. Carter, J. Boyles, C. Holtz, T. Heller, C. Nattrass, M. Fisher, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Remifentanil (4-methoxycarbonyl-4-[(1-oxopropyl)phyenylamino]-1- piperidinepropionic acid methyl ester) is a μ-opioid receptor agonist with considerable abuse potential in racing horses. The identification of its major equine urinary metabolite, 4-methoxycarbonyl-4-[(1- oxopropyl)phenylamino]-1-piperidinepropionic acid, an ester hydrolysis product of remifentanil is reported. Administration of remifentanil HCl (5 mg, intravenous) produced clear-cut locomotor responses, establishing the clinical efficacy of this dose. ELISA analysis of postadministration urine samples readily detected fentanyl equivalents in these samples. Mass spectrometric analysis, using solid-phase extraction and trimethylsilyl (TMS) derivatization, showed the urine samples contained parent remifentanil in low concentrations, peaking at 1 h. More significantly, a major peak was identified as …

Development Of A Blocking Enzyme-Linked Immunosorbent Assay For Detection Of Serum Antibodies To O157 Antigen Of Escherichia Coli., W Laegreid, M Hoffman, J Keen, R Elder, J Kwang

Manuscripts, Articles, Book Chapters and Other Papers

The O157 antigen of Escherichia coli shares structural elements with lipopolysaccharide (LPS) antigens of other bacterial species, notably Brucella abortus and Yersinia enterocolitica 09, a fact that confounds the interpretation of assays for anti-O157 antibodies. To address this problem, a blocking enzyme-linked immunosorbent assay (bELISA) was designed with E. coli O157:H7 LPS as the antigen and a monoclonal antibody specific for E. coli O157, designated 13B3, as the competing antibody. The bELISA had equivalent sensitivity to, and significantly higher specificity than, the indirect ELISA (iELISA), detecting anti-O157 antibodies in sera from cattle experimentally inoculated with O157:H7. Only 13% of sera …

Absence Of Detectable Pharmacological Effects After Oral Administration Of Isoxsuprine, J. Daniel Harkins, G. D. Mundy, S. Stanley, W. E. Woods, R. A. Sams, D. R. Richardson, S. C. Grambow, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Isoxsuprine is reported to be a peripheral vasodilator used in human and veterinary medicine to treat ischaemic vascular disease. In horses, it is generally administered orally to treat navicular disease and other lower limb problems. To deflne the scope and duration of its pharmacological responses after oral administration, 6 horses were dosed with isoxsuprine HCI (1.2 mg/kg bwt) q. 12 h for 8 days and then tested to assess the duration and extent of pharmacological actions. There was no significant difference between isoxsuprine and control treatment values for heart rate, spontaneous activity, sweat production, anal muscle tone, core and skin …

An Overview Of The Methylxanthines And Their Regulation In The Horse, J Daniel Harkins, W. Allen Rees, G. D. Mundy, Scott D. Stanley, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Caffiene, theophylline and theobromine are naturally occurring members of the methylxanthine family;pentoxfylline, dyphylline and enprofylline are structurally related synthetic pharmaceuticals. Caffiene has predominantly central nervous system effects, theophylline, dyphylline and enprofylline have predominantly bronchodilator effects, while theobromine is associated with diuretic responses. Pentoxfylline is thought to increase red cell deformability and facillitate blood flow through capillary beds. The methylxanthines are not highly potent agents; they are typically administered in gram doses and they tend to have relatively long half-lives. They remain detectable in plasma and urine for relatively long periods. Similarly, traces of the naturally occurring members of this family …

The Pharmacologic Effects Of Isoxsuprine, J. Daniel Harkins, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Isoxsuprine is a therapeutic medication used to treat navicular disease and other lower limb problems in horses and is one of the more frequently detected therapeutic agents in racing horses. In crossover studies, horses were administered intravenous and oral isoxsuprine to determine the character and duration of pharmacological effects. Following intravenous administration, isoxsuprine significantly increased heart rate, spontaneous activity, and sweat production. There was an apparent, although statistically insignificant, increase in cutaneous blood flow. Skin temperature decreased below control values, and there was a significant decrease in core temperature. Isoxsuprine also reduced smooth muscle tone. In contrast, after oral dosing, …

Frequency Distribution Of Post Race Urine Ph From Standardbreds Compared With Thoroughbreds: Research And Regulatory Significance, S. D. Stanley, R. A. Sams, J Daniel Harkins, G. D. Mundy, J. Boyles, W. E. Woods, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

The concentration of drugs and drug metabolites in urine samples of racing horses is strongly influenced by urine pH(Tobin, 1981), depending on whether the drugs are weak acids or weak bases. Drugs that are weak acids tend to concentrate in besic urine. In contrast, drugs that are weak bases tend to concentrate in acidic urine. These relationships have a well-established theoretical basis (the Henderson-Hasselbalch relationship) and have been demonstrated repeatedly in experimental animals and man (Tobin, 1981). More recently, evidence suggests that these relationships also occur with clinically and forensically significant agents in equine urine (Wood, et al. 1990; Gerken …

1994 Beef Cattle Report, Darrell W. Nelson

Nebraska Beef Cattle Reports

Two grazing trials were conducted to determine i/protein or energy was first limiting in the spring-and fall-born nursing calf grazing native sandhills range. Spring-born calves supplemented with escape protein gained more rapidly than calves supplemented with energy or nonsupplemented controls. Fall-born calves supplemented with escape protein gained more rapidly than those supplemented with rumen degradable protein or energy and nonsupplemented controls early in the trial, but gained at a similar rate to the energy controls by the end of the trial. Milk intake was similar across treatments for both trials. Escape protein is more limiting in the young nursing calf …

1993 Beef Cattle Report

Nebraska Beef Cattle Reports

Cow-Calf • Forage Systems Using Sandhills Subirrigated Meadows and Range: Beef Production Traits • Forage Systems Using Sandhills Subirrigated Meadows and Range: Economic Analysis • High Quality Meadow Hay as a Winter Supplement for Gestating Beef Cows in the Sandhills of Nebraska • Heifers Sired by Bulls with Either High or Low EPD's for Marbling Do Not Differ in Age at Puberty • Synovex C Affects Growth, Reproduction, and Calving in Heifers • Synthetic Progestins Influence Secretion of Luteinizing and Timing of Ovulation • Level of Progesterone Influences Pregnancy Rate in Beef Cows and Heifers • Combination of Factors (Ratios) …

1992 Beef Cattle Report, Darrell W. Nelson

Nebraska Beef Cattle Reports

Economic efficiency of beef production to weaning and to slaughter was estimated in three groups, different in milk available (low, medium, and high) to the calves but the same in growth potential. Efficiency was the ratio of income to expenses. Income was derived from cull cows and calves at weaning or carcasses of calves fed to slaughter. Feed and non-feed expenses for the cowherd and for calves to weaning or to slaughter were included. Efficiencies were estimated assuming observed reproductive rates and energy requirements for maintenance, as well as for equal reproductive rates and equal requirements for maintenance in the …

Hordenine : Pharmacology, Pharmacokinetics And Behavioural Effects In The Horse, M. Frank, T. J. Weckman, T. Wood, W. E. Woods, Chen L. Tai, Shih-Ling Chang, A. Ewing, J. W. Blake, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Hordenine is an alkaloid occurring naturally in grains, sprouting barley, and certain grasses. It is occasionally found in post race urine samples, and therefore we investigated its pharmacological actions in the horse. Hordenine (2.0 mgkg bodyweight [bwt]) was administered by rapid intravenous (iv) injection to 10 horses. Typically, dosed horses showed a tlehmen response and defecated within 60 secs. All horses showed substantial respiratory distress. Respiratory rates increased about 250 per cent and heart rates were approximately double that of resting values. All animals broke out in a sweat shortly after iv injection, but basal body temperature was not affected. …

1991 Beef Cattle Report, Darrell W. Nelson

Nebraska Beef Cattle Reports

A two-year study tested the hypothesis that growth rate interacts with bull exposure to influence age at puberty in heifers. Heifers exposed to sterile bulls and fed to achieve a high growth rate (1.8 lb/day) attained puberty 73 days earlier than heifers not exposed to bulls and fed to a moderate growth rate (1.3 lb/day). Heifers exposed to bulls and fed to achieve a moderate growth rate attained puberty at ages similar to heifers not exposed to bulls and fed to a high growth rate. Furthermore. heifers receiving these two treatments attained puberty 23 days earlier than heifers not exposed …

The Incidence Of Lupinosis In Sheep Grazing Phomopsis-Resistant Lupin Stubbles, Peter Morcombe, Jeremy Allen

Journal of the Department of Agriculture, Western Australia, Series 4

Lupinosis is one of the major diseases of grazing livestock in Western Australia. It occurs when animals graze lupin stubble containing toxins produced by the fungus Phomopsis leptostromiformis. The Department of Agriculture has recently released new cultivars of Lupinus angustifolius which are more resistant to colonization by Phomopsis, and therefore develop less toxicity, than those previously available (Cowling et al. 1988). The new cultivars - Gungurru and Yorrel - are called Phomopsis-resistant, however their resistance is only moderate. The old cultivars are referred to as Phomopsis-susceptible.

The Detection, Pharmacokinetics And Behavioral Effects Of Diisopropylamine Dichloroacetate (Dada) In The Horse: A Preliminary Report, J.-M. Yang, W. E. Woods, T. J. Weckman, T. W. Wood, S.-L. Chang, J. W. Blake, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

1. Drug administration studies using diisopropylamine dichloroacetate (DADA) and diisopropylamine (DIPA) were conducted in Thoroughbred and Standardbred horses to assess physiological effects and develop detection methods.

2. Four horses received 0.08 mg DADA/kg body wt and showed no changes in heart and respiratory rates or body temperature as measured over a 1-hr period after administration. A transient diuretic effect was found to occur in 2 mares dosed with 0.80 mg DADA/kg body wt.

3. A qualitative detection method using thin-layer chromatography was developed to detect DIPA, the major metabolite of DADA in equine urine. A quantitative detection method (lower limit …

1987 Beef Cattle Report, Irvin T. Omtvedt

Nebraska Beef Cattle Reports

Acknowledgments

Finishing

Determining Moisture of Grain Using Oven, Microwave, and Moisture Tester

Sarsaponin in Receiving Diets of Feedlot Cattle

Effect of Probiotics: Feedlot Receiving Diets

Effect of Roughage Source in Dry or High Moisture Whole Corn Finishing Diets

High Moisure Corn, Dry Grain Combinations for Finishing Cattle

Dry Corn, Wheat Combinations for Finishing Lambs, Cattle

Dry or Wet Corn Bran or Gluten Feed for Ruminants

Corn Gluten Feed: A Review

Methods of Estimating Heat Damage in Protein Sources

Altering Rumen Degradability of Soybean Meal Using Non-Enzymatic Browning

Slaughter Steer Basis, Nebraska Panhandle

Computer Prediction of Finishing Cattle Performance

Cow-Calf

Nutrition …

The Incidence Of Cryptosporidial Infections In Nebraska Dairy Calves, Douglas Lee Varner

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Within the last decade a new etiologic agent has been identified as a possible cause of diarrhea in humans and domestic animals—that being the protozoan parasite Cryptosporidium. The purpose of this study was to determine the incidence and distribution of Cryptosporidium in the state of Nebraska, to determine if Cryptosporidium occurs more frequently in association with other enteropathogens and to determine about the relation of scouring in the calves to infection with Cryptosporidium. A total of 620 fecal samples from 334 dairy calves from 71 herds in Nebraska were examined for cyptosporidial oocysts using the Sheather’s sugar flotation …

Bulletin No 4101 - Flystrike - A Manual For Its Prevention And Control, N Monzu Dr

Bulletins 4000 -

The sheep blowfly is still regarded as the Australian sheep industry's most­damaging pest. Estimates of the cost to the industry, through production losses and prevention and control measures, exceed $ I 00 million in a year. This bulletin comprises the most relevant information available on:

• Blowfly types and life cycles

• Conditions predisposing sheep to flystrike

• The mechanism of flystrike

• Methods of preventing and controlling strike.

• Current research - including the development of a forecasting system for body strike.

Phenylbutazone In The Horse: A Review, Thomas Tobin, S. Chay, S. Kamerling, W. E. Woods, T. J. Weckman, J. W. Blake, P. Lees

Maxwell H. Gluck Equine Research Center Faculty Publications

Phenylbutazone is an acidic, lipophilic, nonsteroidal anti-inflammatory drug (NSAID). It is extensively metabolized in the horse. The metabolites so far identified, oxyphenbutazone, y-hydroxyphenylbutazone and y-hydroxyoxyphenbutazone. account for some 25-30% of administered dose over 24 h. The plasma half-life of phenylbutazone and termination of its pharmacological action are determined primarily by its rate of hepatic metabolism. Phenylbutazone acts by inhibiting the cyclooxygenase enzyme system, which is responsible for synthesis of prostanoids such as PGE?. It appears to act on prostaglalidin-H synthase and prostacyclin synthase, after conversion by prostaglandin-H synthase to reactive intermediates. It markedly reduces prostanoid-dependent swelling, edema, erythema, and hypersensitivity …

Pharmacokinetics And Protein Binding Of Morphine In Horses, Joan Combie, Thomas E. Nugent, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Morphine could be detected in horses dosed with 0.1 mg of drug/kg of body weight for up to 48 hours in blood and 144 hours in urine. This dose of morphine elicited no observ­able effects and is a suggested an­algesic dose. Computer analysis revealed that a 3-compartment open system was the best fitting model with a serum half life of 87.9 minutes and a urine half life of 101.1 minutes. Binding to equine serum proteins was linear over a drug con­centration range of 3.88 x 10-5M to 3.50 x 10-aM and averaged 31.6%. In RBC-partitioning experiments, 78.1 % of the …

1982 Beef Cattle Report, Daniel B. Faulkner, John K. Ward, Terry J. Klopfenstein, University Of Nebraska-Lincoln, V. J. Gibney, J. B. Campbell, D. C. Clanton, D. J. Boxler, M. K. Petersen, Robert A. (Bud) Britton, J. K. Ward, G. Llamas, G. H. Deutscher, B. L. Peverley, J. E. Kinder, M. L. Day, K. Imakawa, R. J. Kittok, W. A. Zollinger, M. K. Nielsen, R. M. Koch, D. S. Buchanan, J. T. Nichols, A. M. Gray, Darrel Myran, Keith Dehaan, Rick Stock, Steve Abrams, Dennis Brink, Felipe Cook, John K. Merrill, Mike L. Mcdonnell, Mark Nelson, Ivan Rush, Ray Carr, Warren Sahs, Abe Turgeon Jr., Dave Harmon, Bob Steele, Paul Q. Guyer, Stanley D. Farlin, Gregory Schindler, Stephen Lowry, Roy G. Arnold, Leo E. Lucas

Nebraska Beef Cattle Reports

Maximizing Forage in Beef Growing-Finishing Rations

Computer Simulation of Plant and Animal Growth

Effects of Cattle Lice on Gains of Cattle Fed Varied Nutrition Levels

Bypass Protein from Blood Meal in Range Supplements

Ammonia Treatment of Wheat Straw

Estrous Synchronization Programs Utilizing Utalyse

Endocrine Regulation of Puberty in the Beef Heifer

Dietary Energy Intake Influence-Reproductive Hormone Secretion in Beef Heifers I

Dietary Energy Intake Influence-Reproductive Hormone Secretion in Beef Heifers II

Genetic Trend in Weaning Weight

Genetic Gain Bias in Weaning Weight Estimated Breeding Values

Selection Applied in Three Lines of Hereford Cattle

Response (Estimated and Predicted) to Selection in …

Worms In Cattle In Western Australia's South West, G C De Chaneet

Journal of the Department of Agriculture, Western Australia, Series 4

In the early 1970s, when beef cattle numbers increased in the South West, worms came to be recognised as the cause of one of the most significant health problems affecting production. The disease ostertagiosis, caused by the brown stomach worm, Ostertagia ostertagi, started to occur regularly, but the anthelmintics available at the time were limited in their efficiency against the parasite. Because little was known of the epidemiology of ostertagiosis under local conditions, recommendations for control were based on observations made elsewhere in Australia and overseas. These were unsuited to local conditions and did not provide adequate control.

Drugs And The Performance Horse, Thomas Tobin

Veterinary Science Books

This book presents an unprecedented account of the actions, effects and consequences of drug use in performance horses. Written for horsemen by a veterinarian and world authority on equine drugs, it deals with all classes, types, and uses of drugs. Professor Tobin describes how the drugs act, how they influence performance, and the problems they may cause. He explains the drug testing process and presents the best information available on the clearance times for drugs in horses. The text is written in plain language and with a touch of humor.

Mechanical, Electrical And Anesthetic Stunning Methods For Livestock, Temple Grandin

International Journal for the Study of Animal Problems

A good stunning method must render an animal unable to experience pain and sensation prior to hoisting and slaughter. The three basic types of stunning methods which are classified as being humane (i.e., pain less) in the United States, Europe and other foreign countries are captive bolt (penetrating and nonpenetrating), electrical, and CO₂ (carbon dioxide) gas anesthesia.

The physiological mechanisms of stress are the same before and after the onset of unconsciousness. The release of epinephrine as a result of stress inducers has an effect on the quality of the meat and it is therefore desirable to use a …

1980 Beef Cattle Report, Leo E. Lucas

Nebraska Beef Cattle Reports

Weighing steers three consecutive days at the beginning and end of the trial reduced variation and increased the probability of detecting a difference in daily gain and gain/protein ratios between treatments when compared to a standard weighing method (once at the beginning and once at the end of the trial). Regressing 1 initial, 1 final and 11 weekly weights also decreased variation and increased the probability of detecting treatment differences compared to the standard method, but was more variable than using three weights at the beginning and end of the trial.

Young, growing steers and lambs supplemented with natural protein …

Testing Bulls For Breeding Soundness, R L. Peet

Journal of the Department of Agriculture, Western Australia, Series 4

New tests are available to ensure that bulls are fertile.

Growth Rate Of Thoroughbreds: Effect Of Age Of Dam, Year And Month Of Birth, And Sex Of Foal, R. L. Hintz, H. F. Hintz, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

Weight, height, and cannon bone measurements were obtained on 1,992 Thoroughbred foals. Colts were heavier than fillies at birth and the differences increased with age. Dams under 7 years of age and older than 11 years had foals of lighter weight at birth than mares 7 to 11 years of age and the differences persisted at 510 days of age. Foals born in April, May, or June were heavier than foals born in January, February, or March. Year of birth also influenced body weight. The trends for height at withers and cannon circumference were similar to those of body weight.