Tuesday, 15 July 2014

Positive Reinforcement Has Its Rewards

Does rewarding a horse during training make a difference? Scientists recently sought to answer that question by comparing how horses respond when trained with and without positive reinforcement.
The researchers worked with twenty horses driven on long-reins in an indoor arena, focussing on training the horses to halt. Half the horses were trained using only negative reinforcement, while the other half received both negative and positive reinforcement.
After five days of training, the two groups responded equally well when asked to halt. But there were signs that the horses which received rewards during training had a demeanour different from the others.
Horses encouraged with positive handling licked their lips more, shook their heads less often, and increased their overall roundedness. All these signs indicate that giving a horse positive reinforcement during training makes for a happier horse.

Doggy Dental Facts

  • Puppies have 28 temporary teeth, 14 in the upper jaw and 14 in the lower jaw. These deciduous teeth erupt at about three to four weeks of age.
  • IllustrationsDogs have 42 permanent teeth, 20 on the top, and 22 on the bottom (Figure 1). These begin to emerge at about four months of age.
  • Dogs have 6 permanent teeth that have 3 roots each, and 14 teeth that each have 2 roots.
  • Puppies should lose a puppy tooth before the corresponding adult tooth emerges. If a puppy tooth is still in place when an adult tooth begins to show it is called a retained deciduous teeth. If this occurs, see your veterinarian so the dog's occlusion is not affected.
  • Studies show that by age three, 80 percent of dogs exhibit signs of gum disease. Symptoms include yellow and brown build up of tartar along the gumline, red inflamed gums and persistent bad breath.
  • Facial swelling below the eye is usually due to an infection of the 4th premolar (carnassial) tooth.
  • Sneezing and nasal discharge may be due to an infection of the upper canine tooth. The infection may lead to an opening between the mouth and the nasal cavity. This is called an oronasal fistula.
  • Small dog breeds are more likely to develop periodontal disease than large dogs because the teeth of small dogs are often too large for their mouths, according to veterinary dentistry experts.
  • A broken tooth is a common problem, especially among outdoor dogs. The canine teeth of working dogs are essential to allowing the dogs to carry prey and other objects. If these teeth become broken, a canine dentist can prepare a metal crown.

Tuesday, 8 July 2014

Horses Find Blue Floors Scary

Horses consider certain floor colours more alarming than others, according to researchers in Nottingham. They documented the reactions of 16 horses to various coloured mats laid as flooring across an aisle. Each horse confronted a coloured floor mat while it was allowed to walk freely along the aisle. Half the coloured mats elicited apprehension and hesitation from the horses.
The horses showed the most unease with yellow, white, black or blue mats laid across their path. They also took longer to walk across these colours than they did with green, red, brown or grey mats.
When the horses encountered the coloured floor mats for a second time, their distress with the scary colors was still evident, although the horses didn't pause any longer before passing over.
In another trial, horses were exposed to the same mats hung against a wall in the stable alleyway, instead of placed on the ground. In this situation, colour made no difference to how the horses reacted to the wall mats.

Friday, 4 July 2014

Lumps and Bumps!

Dogs and cats can develop small bumps (papules) or larger lumps (nodules) on their skin. The term 'tumor' means an abnormal growth or swelling, and is often used to designate cancer. Often, the word 'lump' also brings the word 'cancer' to mind. There are, however, many other causes of lumps and bumps. The following table includes most of the conditions which result in solid lumps and bumps. The list is rather extensive, so you can understand why a quick diagnosis may be difficult to make and various diagnostic tests, such as biopsies, may need to be performed. The most common causes of solid lumps and bumps are color-coded gray in the table (some may be more common in certain geographical areas).

 
ConditionDescriptionSymptomsDiagnosisTreatment
AbscessesAccumulation of pus; may or may not be caused by an infection; in cats, often due to bite woundsThese may appear as firm or fluid-fillednodules of varying shapes and sizes; if due to infection, the animal may have fever, loss of appetite, and depression; may open and drainHistory, physical exam, needle aspirateSurgically open, drain and flush; if infected, administer appropriateantibiotics
Acral lick dermatitis (neurodermatitis)Self-licking in dogs results in self-trauma; possible causes include anxiety, boredom, stress (e.g., new member in household); licking can develop into an obsessive behaviorRed, hairless, well-circumscribed, sometimes raised lesion usually on leg; if chronic, will drainExclude other causes; history importantRelieve underlying cause e.g., anxiety; restrict licking, e.g.,Elizabethan collar; behavior modifying medication may be necessary
Allergic and irritant contact dermatitisAn allergic reaction following exposure to antibiotics applied to the skin; metals such as nickel; materials such as rubber, wool, and plastic; and chemicals such as dyes and carpet deodorizers; or inflammation caused by irritating substances such as poison ivy. Generally requires multiple exposures.Red skin and small bumps or blisters on the areas of skin that are sparsely haired and directly exposed to the offending substance; itching; hair loss in chronic conditionsPatch test, exclusion trialsRestrict exposure to the allergen or contact irritant in the dog's environment; steroids, antihistamines
Apocrine sweat gland cystCommonSingle, round, smooth noduleswith no hair; may appear bluish; usually filled with a watery liquid; most common on head, neck, and limbsPhysical exam; biopsySurgical removal is optional
Basal cell tumorsCancerous, slow-growingtumor which rarely metastasizes; seen in older dogsSingle, sometimes fluid-filled nodules, which may ulcerate; usually on the head, neck, and chest; may behyperpigmentedBiopsySurgical removal
Bee, wasp, hornet stingsSkin reactions can vary dramatically in severityImmediately after the bite, see swelling, redness, pain, possibly itching; subsequently may develop extensiveulcers with draining; may develop hives or anaphylaxisHistory, physical examAntihistamines, steroids; wet dressings, if ulcerated; protect the area from self-inflicted trauma
Benign tumorsSee specific type, e.g., Fibromas, Lipomas, Histiocytomas, Basal cell tumor   
Calcinosis cutisMineralizationof the skin usually due to an excess of corticosteroids; also rarely occurs in kidney failure, or in granulomas andtumorsHard nodules andpapules usually on the back, groin, oraxilla ulcerate, drain, and developcrusts; severe itching; may become infected; often see other signs ofCushing's diseaseSkin scrapings, biopsy, history, and other clinical signs, adrenal gland function testsIf due to glandular tumors, selegiline, o,p-DDD (Mitotane), or surgical removal of tumor; if due to high steroid doses, withdraw use of steroids slowly
CallusResults from chronic pressure, especially in large breed dogsThickened, hairless raised areas over bony pressure points such as elbows; may become secondarily infectedHistory, clinical signsProvide softer bedding and padding around affected area
Canine acneDeep inflammation of hair follicles; exact cause unknown; usually in young dogs; may see secondary bacterial infectionPapules, and sometimes draining lesions on chin and lipsSkin biopsyMild: Benzoyl peroxide; Severe: Also treat with antibiotics
Chiggers (harvest mites)Seasonal disease caused by larvae of the chiggerItching, bumps usually on feet, abdomen (belly), folds at base of earsVisualization of mite larvae or microscopic examination of skin scrapingPyrethrin,Permethrin(Do NOT use permethrin on cats.)
CoccidioidomycosisCaused by the fungusCoccidioides immitis found in the soil in the Southwestern U.S.Draining nodulesover infected bones; usually seerespiratory signs, fever, weight lossMicroscopic examination of drainage; blood testsKetoconazole,itraconazole
CryptococcosisFungal infection often transmitted through bird droppings; more common in dogs with suppressed immune systemsNodules often over the nose, which may ulcerate; many other signs depending on what other body systems are infectedMicroscopic exam of discharge, blood tests, culture, biopsy; look for underlying cause of immunosuppressionItraconazole
Cutaneous hornBenign growths of hard tissue, which look like small horns; cause unknown, though may be associated with some underlying disease such ascancers or follicular cysts½ to 2 inch hard horn-like growths; may be single or multiple; in cats, may occur on foot padsClinical appearance; look for underlying causeSurgical removal
CuterebraCaused by the 1-1½ inch larva of the Cuterebrafly; usually seen in late summerNodule forms around the larva; usually found on the head and neck; nodule has a small opening through which the larva breathes and will eventually escapeClinical signs; opening the nodule and finding the larvaSurgically open the nodule and remove the larva; do NOT squeeze the nodule or break up the larva or a severe allergic reaction may occur
DracunculiasisNodule formed around the parasitic wormDracunculus insignis(Guinea worm)Single or multiple nodules on limbs, head, and belly; nodules may drainClinical signs; opening nodule and finding the female worm (1-4 feet in length!)Surgical removal
Drug or injection reactionRare skin reaction to a drug which is inhaled, given orally, or appliedtopically; more common with penicillins, sulfonamides, and cephalosporins; usually occurs within 2 weeks of giving the drugCan vary widely and may include itching, hair loss, redness, swelling, papules,crustsulcers, and draining woundsHistory of being treated with a drug, symptoms, biopsyDiscontinue offending drug; treat symptomatically
Epidermal inclusion cysts (infundibular cysts)Result from body's reaction to certain skin cellsVery small, up to 2 inch diameternodules, which often contain thick sebaceous materialNeedle aspirate, histopathology on removed noduleSurgical removal may be performed, although new nodules will often form elsewhere; do NOT squeeze these cysts, since a more severe skin reaction will occur
Epitheliotropic lymphoma (mycosis fungoides)Rare cancer ofT lymphocytesseen in older dogsCan take multiple forms: redness with itching and scale;ulcers and loss of pigment; one or more nodules; oral ulcersNeedle or other biopsyPoor response to treatments, which includechemotherapy, surgical removal, retinoids, fatty acids
FibromaUncommonbenign tumorSingle nodule with a pedicle, usually on legs, groin, or sidesBiopsySurgical removal is optional
FibrosarcomaRapidly growing, invasive tumor; may occur at the site of a vaccination or injectionIrregular-shaped, firm nodule; may ulcerateBiopsySurgical removal, however, since tumor is invasive need to remove large area around tumor, sometimes including large masses of muscle and bone; if tumor is on a leg, amputation of the leg is commonly recommended; surgery may be combined with chemotherapy and radiation
Flea allergy dermatitis (flea bite hypersensitivity)Severe reaction by the dog to the saliva of the fleaIntense itching, redness, hair losspapulescrusts, and scales; sometimes development of infection or hot spotsPresence of fleas; reaction tointradermal testingFlea controlin the environment and on the dog; steroids and antihistamines for the itching
Follicular cystMost commoncyst; may be called 'sebaceous cysts' by some veterinariansSingle roundnodules on or underneath the skin; may appear bluish; may contain a thick, yellowish to gray material; usually found on the head, neck, and trunkBiopsySurgical removal optional; do NOT squeeze these cysts, since a severe skin reaction will occur
GranulomasMay be due to infections; the body's reaction to foreign material such as plant material (e.g., foxtail) and suture material; other constant irritation; or unknown causesSolid firm nodulesof varying sizes; those due to foreign bodies often have draining tracts; may develop hair loss,ulcers, andsecondary infectionsHistory, clinical signs, biopsy, surgical exploratorySurgical removal of the foreign body (in the case of plant material, tracts may be extensive and require major surgery); antibiotics, if infected; treat any other underlying cause
HemangiosarcomaMalignant, invasive tumormore common on sun-damaged skinBlue to reddish black nodule; usually on chest or abdomen; often ulcerateBiopsySurgical removal; need to remove large area around the tumor; if tumor is on a leg, amputation of the leg is commonly recommended
HematomaLocalized collection of blood that has leaked out of blood vessels; often occurs in dogs with ear infections and pendulous earsThese may appear as firm or fluid-fillednodules of varying shapes and sizesNeedle aspirateDepending on location and size, may resolve on their own, or need drainage (e.g., on ear flap)
HistiocytomaBenign tumor of younger dogsSolitary raised, rednodules with a strawberry-like appearance; usually on the legs, head, and earsNeedle aspirate, biopsyGenerally resolve on their own; can be surgically removed
HistiocytosisThere are several kinds of histiocytosis:Malignant, which is acancer that affects the skin and internal organs; Systemic, which is a rare disease which affects skin and internal organs;Cutaneous, which is abenign disease affecting the skinAll cause noduleswith hair loss; malignant and systemic also haveulcersBiopsy, fine needle aspirate;Malignant: None effective, may need to consider euthanasia; Systemic: Poor response to chemotherapy; Cutaneous: Corticosteroids, relapse is common, especially in Shar-Peis
HistoplasmosisFungal infection, which can rarely cause skin lesionsUlcerated and draining nodules; most commonly see respiratory and gastrointestinal symptomsNeedle aspirate or biopsyKetoconazole,itraconazole
HookwormsInfection with the larvae (immature forms) of hookwormsRed bumps, usually on feet, rough foot pads, abnormal nail growth, itchingPhysical exam, history of poor sanitationTreat for intestinal infection; move dog to different environment
Infundibular keratinizing acanthomaRare benignnodules more common in young Norwegian ElkhoundsOne or more small to 1½ inch nodules, with small opening through which thick material can be expressedBiopsySurgical removal; retinoids, if multiple lesions
KerionComplication of ringworm infectionNodule with hair loss and multiple draining tracts; may not see other signs of ringwormCulture, biopsyClip area and apply topicaltreatment and shampoos; may require systemic treatment with ketoconazole oritraconazole
LeishmaniasisCaused by a parasite of blood cells; can be transmitted to people who develop a very severe diseaseHair loss, scaling,ulcers on nose and ears, sometimesnodules; many other nonskin-related signsIdentify the organism in blood or biopsy; blood testsBecause it causes severe disease in people, and treatment of dogs is not curative, euthanasia may be performed
Lichenoid dermatosisOften a response to other underlying disease such as fleas or bacterial infectionsSmall flat noduleswith thick surfacesBiopsy, look for underlying diseaseTreat underlying cause; this reaction usually resolves on its own
LipomaUncommonbenign fatty tumorUsually single, soft, domed nodule; can become very largeFine needle biopsySurgical removal, if large or interferes with movement
LymphomaCommon cancer in dogs; can involve the skinItching, ulcers, nodules, rednessBiopsySurgery, chemotherapy, radiation; lymphoma of the skin does not usually respond to treatment as well as other lymphomas
Mammary cancerMost common in unspayed females; in dogs, 50% aremalignantSingle or multiplenodules under the skin, of varying sizes, often irregular in shape; may ulcerate and drainBiopsySurgical removal
Mast cell tumorCommoncancer which is graded from 1-4: Grade 1 is slow-growingtumors, and Grade 4 is rapidly growingmalignanttumors with metastasesTumors may be of various sizes, appearances, and numbersBiopsy to grade the tumors, which determines treatment and prognosisDepends upon grade; surgical removal, taking large area around tumor; chemotherapy; prednisone; radiation
MelanomaMalignanttumor of older dogsUsually single dark-colored nodule, which often ulceratesBiopsySurgical removal, taking large area around tumor
NeviUsually benignlesions; some types may indicate the presence of an underlying diseaseWell-delineated firmnodules, often multiple and on the head and neckBiopsySurgical removal, although recurrence is common; depending upon the type, look for underlying disease
NocardiaBacterial infection usually acquired from a puncture woundUsually see respiratory signs; skin lesions include draining nodulesBacterial culture, microscopic examination of drainagePoor prognosis; antibiotics
PanniculitisMay be caused by trauma, foreign bodies, infections, autoimmune diseases or unknown causesDeep-seatednodules, often ulcerated and draining; usually on the body vs. the head or limbs; may see loss of appetite, depressionMicroscopic exam of drainage; biopsy; tests to rule out other causesSurgical removal; if multiple lesions, prednisone and Vitamin E; may need long-term treatment
Pelodera dermatitisAccidental infection with larvae from a non-parasitic worm that lives in straw and other organic materialAffects areas of skin touching ground; intense itching, redness, hair loss,papulescrusts, and scalesSkin scraping and microscopic examinationRemove bedding; mild antibacterial shampoo; steroids if necessary, to control itching
PhaeohyphomycosisCaused by wound contamination with a fungusA single nodule on the legs or multiple ulcerated and draining nodules over the bodyMicroscopic examination of drainage, culture, biopsySurgical removal, though often recurs; possibleantifungalmedications
Pyoderma-deep (bacterial infections of skin and underlying tissue)Often secondary to another skin disease such as self-inflicted trauma, wounds, acral lick granulomas, allergies, seborrheaUlcerated pustulesor nodules, draining tracts,crusts, and thickened skinSkin scrapings, biopsy, cultureClip and cleanse area; antibiotics, prevent self-trauma (licking, scratching), NO Steroids
PythiosisCaused by an aquatic moldUlcerated draining nodules on the legs, head, and base of tail, which may itch; often see other signs of illness due to infection of the gastrointestinal tractMicroscopic examination of drainage; biopsyOften fatal; surgical removal
RingwormInfection with several types of fungusHair loss,scalinesscrustyareas, pustules, and vesicles, some itching; can develop a draining nodulecalled a 'kerion'CultureMiconazole, lime sulfur dips; oralgriseofulvinoritraconazole
Sarcoptic mangeInfection with the SarcoptesmiteIntense itching and self-trauma, hair loss, papules,crusts, and scalesSkin scraping and microscopic examination - the mite is often very difficult to findAmitraz (Mitaban) dips (off-label use*); ivermectin (off-label use*)
Schnauzer comedo syndromeUncommon; only seen in Miniature SchnauzersComedones (black heads) on back, mild itching; may see secondary infection, thinning of hair; small crusts may developClinical signs, breed, skin biopsyLong-term antiseborrheic shampoos; sometimes antibiotics and retinoids
Sebaceous gland cystExtremely rareFirm nodules, usually less than ½ inch in diameterBiopsySurgical removal
Sebaceous gland tumorsCommon; rarely spread or recur; several typesNodules, which may ulcerate; usually on the head and legsBiopsySurgical removal, if invasive; if abenign lesion, removal is optional
Skin cancerSee specific type, e.g., Fibrosarcoma, Melanoma, Squamous cell carcinoma, Mast cell tumor, Lymphoma   
Spider bites/eosinophilic folliculitisBites from some spiders and caterpillars contain strong toxins; usually appear on the nose of dogs and paws of catsImmediately after the bite, swelling, redness, pain; subsequently may develop extensiveulcers with drainingHistory, biopsyCorticosteroids, wet dressings, protect the area from self-inflicted trauma; may develop permanent loss of hair and scarring
SporotrichosisCaused by the fungusSporothrix schenckii, which generally enters through a puncture woundRaised noduleswith multiple draining tracts; cats may develop fever, depression, and loss of appetiteMicroscopic exam of drainage; culture; fluorescent antibody testPotassium iodide, ketoconazole,itraconazole
Squamous cell carcinomaCommonmalignanttumor; may occur more commonly in sun-damaged or chronically irritated skinTwo forms: Cauliflower-like lesions, often ulcerated more common on lips and nose; Crustedulcers on limbs or bodyBiopsySurgical removal, radiation,hyperthermia
Superficial necrolytic dermatitis of Miniature SchnauzersSkin reaction to shampoos (usually insecticidal or medicated)Papulespustules, and ulcers with drainage; develop 2-3 days after exposure to the shampoo; may also see fever and depressionBreed, history of exposure, clinical signsTreat symptomatically
Tail dock neuromaNerve regrowth after tail docking causes symptomsNodule at site of docking, itching with self-mutilation, hair loss, andhyperpigmentationHistory and symptomsSurgical removal
Tail gland hyperplasiaDogs have asebaceous gland on the top of the tail near its base; in this disorder, the gland enlarges; seen in unneutered dogs and secondary to other diseases such as hypothyroidismOily area, hair loss,crusts, andhyperpigmentationon area over glandClinical signs; look for underlying causeCastration may help; treat underlying cause; surgical removal
Tick bitesTicks cause a local inflammation in the skin, even when the entire tick is removedNodule and redness at site of the bite; may itch and develop crusts; may last several monthsHistoryRemove the tick; use a tick preventive; allow nodule to resolve on its own
Urticaria (hives)Reaction, often allergic, to insect bite, drug, vaccine, sunlight, etc.Multiple swellings, with hair standing up over swellings; itching may occurHistory, physical examOften resolves on its own; in the case of allergic reactions, antihistamines, epinephrine, or corticosteroids depending upon severity
Warts (cutaneous papilloma)Benign growths caused by a virus; usually seen in puppiesLight-colored growths with a cauliflower appearance; usually on the lips, tongue, inside of the mouth, and eyelidsClinical appearance, biopsyUsually none - they resolve by themselves; if severe, removal by cryosurgery
ZygomycosisUncommon fungal diseaseDraining nodules; may also see pneumonia, vomiting, or jaundice depending upon the body organs involvedMicroscopic examination of the drainage; biopsyOften fatal; surgical removal of nodules followed by amphotericin B, benzimidazoles, or potassium iodide
 
 
References and Further Reading
Birchard, SJ; Sherding RG (eds.) Saunders Manual of Small Animal Practice. W.B. Saunders Co. Philadelphia, PA; 1994.
Greene, CE (ed.) Infectious Diseases of the Dog and Cat. W.B. Saunders Co. Philadelphia, PA; 1998.
Griffin, C; Kwochka, K; Macdonald, J. Current Veterinary Dermatology. Mosby Publications. Linn, MO; 1993.
McKeever, PJ; Harvey, RG. Skin Diseases of the Dog and Cat. Iowa State University Press. Ames, Iowa; 1998.
Paterson, S. Skin Diseases of the Cat. Blackwell Science Ltd. London, England; 2000.
Paterson, S. Skin Diseases of the Dog. Blackwell Science Ltd. London, England; 1998.
Scott, D; Miller, W; Griffin, C. Muller and Kirk's Small Animal Dermatology. W.B. Saunders Co. Philadelphia, PA; 1995.

Tuesday, 24 June 2014

Getting ready for the Summer heat

Summer heat can be dangerous for horses, resulting in dehydration, lethargy, and general malaise. Severe heat stress can cause diarrhea, or even colic. But owners can take important steps to keep horses safe and comfortable during the hot days ahead.
In a release issued June 19, Janet Johnston, DVM, Dipl. ACVIM, ACVS, an emergency critical care veterinarian at University of Pennsylvania School of Veterinary Medicine's New Bolton Centre, suggested the following ten tips to keep your horse comfortable and safe in the summer heat.
1. Choose cooler turnout times. If your horse has a stall but is turned out for part of the day, provide turnout during the cooler hours. Overnight is ideal, but if that's not possible, turnout as early as possible during the day.
2. Provide shade. If your horse lives outdoors or if he must be outside during the day, provide relief from the sun. A run-in shed is best. Trees are a source of shade, but as the sun moves, so will the shade; ensure that, regardless of the time of day, the trees are offering shade.
3. Move the air. Fans are a great way to help keep the air moving in the barn, but use them wisely. Always ensure that your horse can't get a hold of cords and plugs.
4. Mist your horse. If you are fortunate enough to have a misting system for your horse, use it. As moisture is absorbed from your horse’s skin, it will take away some of the heat. Frequent mistings are far more effective than a single dousing with a hose.
5. Provide fresh, cool water. Make sure your horse has plenty of fresh, cool water. A bucket hanging on a pasture fence will get warm, and the water will no longer be appealing. Left long enough, the water will also become stagnant and unhealthy. If you are providing clean, cool water and your horse doesn’t seem to be drinking enough, encourage him to consume water by providing a salt block, or even by misting hay with salt water.
6. Offer electrolytes. If your horse is sweating a great deal, an electrolyte supplement or water laced with electrolytes can help keep his body in balance. Whenever you offer electrolytes, however, be sure to offer fresh water, as well. Too many electrolytes can be harmful.
7. Slow down the work. Don’t think that because your horse has been working intensely at 1 p.m. every day that he can take the heat when the temperature tops 90°. If you have to work your horse in the heat, lighten the work or spread it out over a couple of short sessions. This is especially important when the humidity is high, which can diminish the poor quality of the air your horse is breathing.
8. Stick to a schedule. Within the parameters of keeping him cool, try to stay as close as possible to his normal schedule. Too much change at one time can be an invitation for colic.
9. Avoid sunburn. Horses, especially white horses, can suffer from sunburn. Even those with white socks and blazes, pink noses, or hairless patches from scarring can be susceptible. Using a fly scrim can help. In addition, applying sunblock to small, particularly vulnerable areas can be effective. Staying out of the sun’s harmful rays will, of course, be best. (Also be aware: If a horse has excessive sunburn it could indicate a rare, underlying liver disease.)

10. Clip horses with longer hair coats. Clipping is important, especially for those with pituitary pars intermedia dysfunction (PPID, or equine Cushing's disease). While some coat can provide protection from the sun and insulation, a long, thick coat tends to hold heat and makes it difficult for the horse to cool down.