Pharmacotherapy2020

Pharmacotherapy of bacterial and fungal diseases

Prudent use

• Great responsibility

• Prevention

• Good hygiene

• Good system:

• modern equipments,

• effective disinfection,

• clean drinking water,

• good quality feed,

• filtered air ventilation.

• All in/all out

• But

• Only if necessary

• Based on sensitivity test

• Narrow spectrum antimicrobials first

• Appropriate dose and duration

• Avoid CIAs in farm animals

Sensitivity test

• The MIC, or minimum inhibitory concentration, is the lowest concentration (in μg/mL) of an antibiotic that inhibits the growth of a given strain of bacteria.

• The MIC is the standard in vitro measure of the potency of an antimicrobial agent.

• A quantitative method of susceptibility testing.

• S (sensitive), the organism is inhibited by the serum concentration of the drug that is achieved using the usual dosage.

• I (intermediate), the organisms are inhibited only by the maximum recommended dosage.

• R (resistant), organisms are resistant to the usually achievable serum drug levels.

MIC and MBC

MIC and MPC

Prudent use

CategoryRisk to Public

HealthAntimicrobials Included Advice on use

A. Authorised CIAs

1Low/limited risk

to public health

Narrow spectrum Penicillins,

Macrolides, Tetracyclines

General principles of

responsible use to be

applied

2Higher risk to

public health

Fluoroquinolones, systemic

3rd /4th generation

Cephalosporins,

(Aminoglycosides, broad-

spectrum Penicillins), Colistin

Restricted to use where

there are no alternatives

or response to

alternatives expected to

be poor

Treatment of pyoderma

• Pyoderma literally means “pus in the skin”, most commonly, pyodermarefers to bacterial infections of the skin.

• Pyodermas are common in dogs and less common in cats.

• Bacterial pyodermas are either simple infections or complex infections.

• Simple infections are those occurring in young animals that are triggered by one-time or simple events, e.g. flea infestation.

• Complex infections are recurrent and are associated with underlyingdiseases:

- allergies (flea allergy, atopic dermatitis, food allergy)

- internal diseases (endocrinopathies such as hypothyroidism orhyperadrenocorticism)

- seborrheic conditions (including follicular or sebaceous gland diseases)

- parasitic diseases (eg, Demodex canis)

- anatomic predispositions (eg, skin folds).

Treatment of pyoderma

• Either simple or complex infections can be superficial or deep.

• The primary pathogen of dogs is Staphylococcus pseudintermedius.

• NOT: Amoxicillin, penicillin, and tetracycline, because they are ineffective in 90% of these cases.

• Fluoroquinolones should be used only if based on susceptibility test.

• Polymyxin combinations (bacitracin) are more effective againstGram-negative bacteria than other topical antibiotics but are inactivated in purulent exudates.

• Dogs with superficial pyoderma should be bathed 2–3 times/week during the first 2 weeks of therapy and then 1–2 times until the infection has resolved.

Treatment of pyoderma

• Dogs with deep pyoderma may require daily hydrotherapy. Medicated shampoos should be prediluted 1:2 to 1:4 before application to facilitate lathering, dispersal, and rinsing.

• Appropriate antibacterial shampoos include benzoyl peroxide, chlorhexidine, chlorhexidine-ketoconazole, ethyl lactate, and triclosan.

• Shampooing will remove bacteria, crusts, and scales, as well as reduce the pruritus, odor, and oiliness associated with the pyoderma.

• Clinical improvement in superficial pyodermas may not be evident for at least 14–21 days, and recovery may not be as rapid as expected.

• NOT fluoroquinolones and second- and third-generation cephalosporins as empirical therapy to minimize the development of multi-resistant staphylococci!

Treatment of greasy pig disease

• Exudative epidermitis is a generalized dermatitis that occurs in 5- to 60-day-old pigs and is characterized by sudden onset, with morbidity of 10%–90% and mortality of 5%–90%.

• Lesions are caused by Staphylococcus hyicus, which can produce an exfoliative toxin but seems unable to penetrate intact skin. Both virulent and avirulent strains exist.

• Pigs develop resistance with age, but S. hyicus may be recovered from the skin of older pigs.

• The causative organism is inhibited by many antibiotics, including amoxicillin, ampicillin, erythromycin, lincomycin, penicillin, tylosin, trimethoprim-sulfonamide, aminoglycosides, and cephalosporins.

Treatment of greasy pig disease

• Successful treatment requires that the antimicrobial be given in high dosages early in the disease and for 7–10 days. Success is greatest when antimicrobial therapy is combined with daily applications of antiseptics to the entire body surface.

• Treatment is less effective in very young pigs and ineffective in advanced cases.

• In severe outbreaks, in-contact pigs should also be given antibiotics for several days.

• Sows due to farrow, and their housing, should be thoroughly disinfected toprevent outbreaks.

• Hygiene in the weaner accommodation and strategic in-water orin-feed medication for 3–5 days will help control outbreaks afterweaning.

Treatment of dermatophylosis

• Dermatophilus infection, Cutaneous streptothricosis, Lumpy wool,

Strawberry footrot

• Dermatophilus congolensis has a wide host range. Not very frequent in Europe.

• Cattle, sheep, goats, and horses are affected most frequently, and pigs, dogs,

and cats rarely.

• Acutely infected animals usually heal rapidly and spontaneously, treatment was

indicated only for cosmetic reasons in food-producing animals.

• However, in certain parts of the world, the disease is associated with significant

morbidity and mortality, loss of body condition, decreased milk production, and

increased somatic cell counts in milk.

• Treatment is recommended in horses because the lesions interfere with use

and are painful.

Treatment of dermatophylosis

• Organisms are susceptible to a wide range of antimicrobials:

erythromycin, spiramycin, penicillin G, ampicillin, chloramphenicol,

streptomycin, amoxicillin, tetracyclines, and novobiocin.

• Two doses of long-acting oxytetracycline (20 mg/kg) 1 day apart have shown to

be curative in 85% of cattle and 100% of sheep, compared with cure rates of

71% in cattle and 80% in sheep for a single dose.

• In food-producing animals, topical applications of lime sulfur are a cost-

effective adjuvant to antibacterial therapy.

• In horses, the lesions should be gently soaked and removed. Topical

antibacterial shampoo therapy is effective as adjuvant therapy. Chlorhexidine is

recommended.

• Topical treatment with povidone-iodine is superior to parenteral oxytetracycline

alone.

Treatment of bovine pleuropneumonia

• Contagious bovine plueuropneumonia is caused by Mycoplasma mycoidesmycoides small colony type.

• Susceptible cattle become infected by inhaling droplets disseminated by coughing in affected cattle.

• The disease is reportable by law in many countries from which it has been eradicated by slaughter of all infected and exposed animals.

• Treatment is recommended only in endemic areas because the organisms may not be eliminated, and carriers may develop.

• Tylosin (10 mg/kg, IM, bid, for six injections) and danofloxacin 2.5% (2.5 mg/kg/day for 3 consecutive days) have been reported to be effective.

Treatment of bovine pleuropneumonia

• Mycoplasma mycoides mycoides small colony type.

• Danofloxacin has concentration dependent bactericidal activity

• Rapidly and extensively absorbed from the site of subcutaneous injection, bioavailability is around 90%.

• Poorly metabolised and subsequently eliminated via both the renal and hepatic routes.

• A difference in elimination kinetics is observed between pre-ruminant animals (half-life of 12 hours) and ruminant animals (half-life of 4 hours).

• High drug concentrations in lung, enteric and lymphatic tissues are observed.

• Concentrations in lung and enteric tissues approximately four times greater than in plasma.

Treatment of bovine pleuropneumonia

• Mycoplasma mycoides mycoides small colony type.

• Macrolides are binding to the 50S ribosomal subunit and inhibiting protein synthesis in susceptible micro-organisms.

• They are bacteriostatic at therapeutic concentrations and this action is time dependent.

• Following intramuscular injection, tylosin blood levels peak 1-2 hours post-injection.

• Duration of activity is approximately 12 hours.

• Tylosin concentrations are greater in lung tissue than in serum.

Treatment of bovine respiratory disease

• Mannheimia haemolytica serotype 1 is the bacterium most frequently isolated from the lungs of cattle with BRD.

• Pasteurella multocida is also an important cause of bacterial pneumonia.

• Histophilus somni may invade the lung and cause pneumonia after damage to the respiratory defenses.

• Long-acting antimicrobials such as tulathromycin, gamithromycin, tildipirosin, tilmicosin, florfenicol, and enrofloxacin are effective

• NSAIDs have been shown to be a beneficial ancillary therapy in controlling fever in cases of BRD.

+ Tuloxxin, Tulaxa 100 mg/ml Solution for Injection for Cattle, Pigs and Sheep

Treatment of bovine respiratory disease

• Mannheimia haemolytica, Pasteurella multocida, Histophilus somni

• Tulathromycin is a semi-synthetic macrolide antimicrobial.

• It differs from many other macrolides in that it has a long duration of action that is,partly due to its three amine groups: triamilide.

• After single subcutaneous dose of 2.5 mg/kg bodyweight; rapid and extensive absorption followed by high distribution and slow elimination.

• Tulathromycin concentrations in lung considerably higher than in plasma.

• Plasma protein binding is low, approximately 40%.

• The bioavailability of tulathromycin after subcutaneous administration in cattle was approximately 90%.

• Tildipirosin (Zuprevo inj.), gamithromycin (Zactran inj.) aresimilar long acting drugs.

+ Tuloxxin, Tulaxa 100 mg/ml Solution for Injection for Cattle, Pigs and Sheep

Treatment of bovine respiratory disease

• Mannheimia haemolytica, Pasteurella multocida, Histophilus somni

• Florfenicol is a synthetic broad spectrum antimicrobial.

• Florfenicol acts by inhibiting protein synthesis at the ribosomal level and is bacteriostatic.

• In cattle, intramuscular administration at the recommended dose of 20 mg/kg maintains efficacious blood levels in cattle for 48 hours.

• The administration of the product by subcutaneous route at the recommended dosage of 40 mg/kg maintains bovine efficacious blood levels in cattle .

• The elimination half-life is 18 hours.

Necrotic Laryngitis in Cattle

• Calf diphtheria, Laryngeal necrobacillosis; USA: 1-2%, Europe: 0,1%

• Necrotic laryngitis is an acute or chronic Fusobacterium necrophorum infection of the laryngeal mucosa and cartilage of young cattle, characterized by fever, cough, inspiratory dyspnoea, and stridor.

• Oxytetracycline (11 mg/kg, IV or SC, bid, or 20 mg/kg of long-acting tetracycline, SC,every 72 hr) or procaine penicillin (22,000 U/kg, IM, bid) are the antimicrobials of choice.

• NSAIDs (aspirin, 100 mg/kg, PO, bid; flunixin, 1.1–2.2 mg/kg, IV, once daily or dividedbid; or ketoprofen, 3 mg/kg/day, IM or IV, for up to 3 days) are used to decrease the fever and laryngeal inflammation and oedema.

• A single dose of dexamethasone (0.2–0.5 mg/kg, IV or IM) may be used to decrease laryngeal oedema in animals with severe respiratory distress.

Necrotic Laryngitis in Cattle

• Oxytetracycline is a bacteriostatic antibiotic it binds irreversibly to receptors on the 30S subunit of the bacterial ribosome where it interferes with the binding of the aminoacyl-transfer RNA to the acceptor site on the messenger RNA ribosome complex.

• Oxytetracycline is widely distributed in the body, including to the kidneys, liver, lungs and muscle.

• The placenta is readily passed by oxytetracycline and concentration in the fetal blood may reach that of the maternal circulation.

• Oxytetracycline is not metabolised in vivo and is eliminated primarily unchanged, via glomerular filtration. It is also excreted into the GI tract via both biliary and non-biliary routes and may become inactive after chelation with faecal material.

Necrotic Laryngitis in Cattle

• Penicillin G = benzylpenicillin

• Procaine penicillin G is specifically formulated to provide sustained antibacterial activity following a single administration.

• The procaine penicillin is rapidly absorbed from the site of injection.

• It is widely distributed in the extracellular fluids after absorption, and eliminated almost entirely by the kidneys.

• The procaine penicillin gives high initial blood levels.

• The penicillin elimination half-lives are approximately 16 hours following intramuscular injection and 8.5 hours following subcutaneous injection.

• Treatment may be repeated at 24 or 48 hour intervals to maintain therapeutic levels.

Pharyngitis, tonsillitis

• Escherichia coli, Staphylococcus aureus, and hemolytic streptococci are thepathogenic bacteria most often cultured from diseased tonsils.

• Penicillins are often effective, but in refractory cases, culture and sensitivity testing may be needed.

• Bacterial pharyngitis should be treated with systemic antimicrobials based on microbial culture and sensitivity testing. (Cephalosporins, penicillins, macrolides, lincosamides)

Sinusitis, Coryza

• Mycoplasma gallisepticum is commonly involved in the polymicrobial "chronic respiratory disease" of chickens; in turkeys, it frequently results in swollen infraorbital sinuses and is called "infectious sinusitis."

• Most strains of M. gallisepticum are sensitive to a number of broad-spectrum antibiotics, including tylosin, tilmicosin, tetracyclines.

• Tylosin or tetracyclines have been commonly used to reduce egg transmission or as prophylactic treatment to prevent respiratory disease in broilers and turkeys.

Sinusitis, Coryza

• Infectious coryza is an acute respiratory disease of chickens characterized by nasal discharge, sneezing, and swelling of the face under the eyes.

• Erythromycin and oxytetracycline are usually beneficial.

• Several new-generation antibiotics (eg, fluoroquinolones, macrolides) areactive against infectious coryza.

• Various sulfonamides, sulfonamide-trimethoprim, and other combinationshave been successful.

Pneumonia, rhinitis

• Mycoplasmal pneumonia is a chronic, clinically mild, infectious pneumonia of pigs, characterized by its ability to become endemic in a herd and to produce a persistent dry cough and retarded growth rate.

• When the disease first enters a herd, mass treatment with antibiotics (eg, tylosin,tilmicosin, lincomycin, tiamulin, or a tetracycline) helps to control the severity of signs.

• The disease has been divided into two forms:

• - nonprogressive atrophic rhinitis, due to B. bronchiseptica, is mild and transient and probably does not greatly affect the pig’s growth and performance;

• - progressive atrophic rhinitis, due to toxigenic P. multocida, is severe, permanent, and usually accompanied by poor growth.

• Drugs commonly used are ceftiofur, sulfonamides, tylosin, and tetracyclines.

Sulfadiazine, Trimethoprim

Tracheobronchitis in Small Animals

• Canine infectious tracheobronchitis (kennel cough) is often secondary to viral infectionof the respiratory system.

• Other causes of tracheobronchitis in dogs include parasites, eg, Aelurostrongylusabstrusus (also in cats), Capillaria aerophila, Crenosoma vulpis, and Oslerus osleri.

• Cough suppressants containing codeine derivatives, such as hydrocodone (0.25 mg/kg, PO, bid-qid) or butorphanol (0.05–0.1 mg/kg, PO or SC, bid-qid), should be used only as needed to control persistent nonproductive coughing.

• Antibiotics are usually not needed except in severe chronic cases; cephalosporins, quinolones, chloramphenicol, and tetracycline are preferable because they reach effective concentrations in the tracheobronchial mucosa.

• Antibiotics given PO or IM may not significantly reduce the numbers of B.bronchiseptica in the distal trachea or major bronchi.

• Thus, in severely affected dogs that are not responsive to parenteralantibiotics, kanamycin sulfate (250 mg) or gentamicin sulfate (50 mg)diluted in 3 ml of saline may be administered by aerosolization bid for 3 days.

Feline Respiratory Disease Complex

• Feline respiratory disease complex includes those illnesses typified byrhinosinusitis, conjunctivitis, lacrimation, salivation, and oral ulcerations.

• The principal diseases, feline viral rhinotracheitis (FVR; feline herpesvirus type1), feline calicivirus (FCV), Chlamydia felis, Mycoplasma felis, or combinations of these infections, affect exotic as well as domestic species.

• Treatment is largely symptomatic and supportive, but broad-spectrumantibiotics are useful against secondary bacterial invaders (eg, amoxicillin withclavulanic acid, cephalosporins, trimethoprim-sulfa, fluoroquinolones, tetracyclines, chloramphenicol) as well asdirectly against C. felis and M. felis.

Feline Respiratory Disease Complex

• Tetracyclines and fluoroquinolones are the most effective against C. felisand M. felis.

• Nasal and ocular discharges should be removed frequently for the comfort of the cat.

• Nebulization or saline nose drops may aid in the removal of tenacious secretions.

• Nose drops containing a vasoconstrictor (eg, two drops of ephedrine sulfate [0.25% solution] in each nostril, bid) and antibiotics may help reduce the amount of nasal exudate.

Rhodococcus equi

• Rhodococcus equi is the most serious cause of pneumonia in foals 1–4 months old.

• The combination of erythromycin (25 mg/kg, PO, qid; esters or salts) and rifampicin (5–10 mg/kg, PO, bid) has historically been the treatment of choice for R. equi infection in foals.

• Clarithromycin is the macrolide of choice for foals with severe disease.

• The combination of clarithromycin (7.5 mg/kg, PO, bid) and rifampicinis superior to erythromycin-rifampicin and azithromycin-rifampicin.

• Foals treated with clarithromycin-rifampicin have improved survivalrates and fewer febrile days than foals treated with erythromycin-rifampicin and azithromycin-rifampicin.

• Reported adverse events of clarithromycin-rifampicin include diarrhoeain treated foals.

Mycotic pneumonia

• Cryptococcus neoformans, Histoplasma capsulatum, Coccidioides immitis, Blastomyces dermatiditis, Pneumocystis jiroveci, Aspergillus spp., Candida spp.

• Aspergillosis is most commonly associated with sinonasal infection in dogs or sino-orbital infection in cats, with systemic infection being quite rare and seen only in immunocompromised individuals.

• Cryptococcosis most commonly affects the nasal cavity in cats, with CNS infection less commonly encountered in dogs and cats.

• Treatment of mycotic pneumonia is often lengthy.

• Drugs of choice include itraconazole, fluconazole (cryptococcosis), lipid-complexedamphotericin B, and terbinafine (aspergillosis).

• Newer generation azole antifungals such as voriconazole or posaconazole are more effective for resistant infections or systemic aspergillosis.

Bovine Cystitis and Pyelonephritis

• Bovine cystitis is an inflammation of the urinary bladder of cattle that may ascend the ureters to cause infection of the kidneys (pyelonephritis).

• E. coli and Trueperella (formerly Arcanobacterium or Corynebacterium) pyogenes aremost frequently isolated from cows with pyelonephritis.

• Other opportunistic and environmental bacteria may be involved, includingstaphylococci and streptococci.

• The treatment of choice for pyelonephritis due to Corynebacterium spp. is penicillin(22,000 IU/kg, IM, bid) or trimethoprim-sulfadoxine (16 mg/kg, IM, bid) for ≥3 wk.

• The dosage, frequency, and length of administration for both of these drugs isextra-label, and adequate precautions must be taken to prevent antibioticresidues from entering the human food supply.

• E. coli infections require a broad-spectrum antimicrobial.

• Ceftiofur (1.1–2.2 mg/kg/day, IM or SC) or gentamicin (2.2 mg/kg, IM, bid) for ≥3 week have been used successfully in some cases.

• Because of the extremely long tissue-depletion time, the aminoglycosidesmay not be indicated in food-producing animals. (eg. 192 days WP)

Treatment of Urinary tract infections

• Common organisms include Escherichia coli, Staphylococcus, Enterococcus, and Streptococcus.

• Less common organisms causing infection include Klebsiella, Proteus, and Pseudomonas. Pasteurella is more common in cats than dogs.

• Bacterial infections of the urinary tract typically ascend from the urethra into the bladder and in some cases into the kidneys.

• Simple bacterial cystitis is treated for 2 wk. with a broad-spectrum antibiotic that achieves a high concentration in the urine.

• Initial choices include amoxicillin (10–20 mg/kg, PO, bid-tid), cefadroxil (22–30 mg/kg, PO, bid), cefpodoxime (5–10 mg/kg/day), SUA+TMP (25mg/kg, PO, day one, then 12.5 mg/kg/day, PO), or cefovecin (8 mg/kg, SC, day one, which may be repeated once 7 days later).

Treatment of Urinary tract infections

• A repeat urine culture 3–7 days after oral therapy or on day 21 if cefovecin is used is recommended.

• Pyelonephritis should be treated aggressively with broad-spectrum antibiotics, based on urine culture and antimicrobial susceptibility testing, for 4–8 week.

• The infection may respond to the same antibiotics recommended for cystitis, but more frequent administration (eg. amoxicillin tid rather than bid) and/or higher dosages are indicated.

• A fluoroquinolone or a combination of a fluoroquinolone with a β-lactam antibiotic is often effective.

Treatment of mastitis in cattle

• Most infections are caused by various species of streptococci, staphylococci, and Gram-negative rods, especially lactose-fermenting organisms of enteric origin, commonly termed coliforms.

• Staphylococcus aureus, Streptococcus agalactiae, and Corynebacterium bovis.

• Subclinical mastitis is the presence of an infection without apparent signs of local inflammation or systemic involvement.

• Staphylococcus hyicus, Staphylococcus epidermidis, Staphylococcus xylosus, and Staphylococcus intermedius.

• Depending on susceptibility testing, lipophilic antibacterial drugs that distribute well into mammary tissue, such as oxytetracycline (11 mg/kg/day) are the best candidates for systemic administration.

Treatment of mastitis in cattle, intramammary

• Dry cows: Numerous products are available and include penicillin, cloxacillin, cephapirin, ceftiofur, dihydrostreptomycin, neomycin or novobiocin.

• One tube per quarter is sufficient and should be administered immediately after the last milking of lactation.

• Systemic administration should be used as an adjunct to the intramammary infusion, in case of extended infection.

• Heifers: Intramammary infusions of β-lactam antibacterial drugs 7–14 days before expected calving dates have been reported to reduce the rate of intramammary infections at calving.

Treatment of mastitis in cattle

• Clinical mastitis is an inflammatory response to infection causing visibly abnormal milk (eg, color, fibrin clots). As the extent of the inflammation increases, changes in the udder (swelling, heat, pain, redness) may also be apparent.

• 90%–95% of the isolated bacteria include a wide variety of streptococci, staphylococci, or coliforms.

• Severe clinical mastitis: Coliforms (lactose-fermenting Gram-negative rods of the family Enterobacteriaceae) are the most common cause of this.

• Many inflammatory and systemic changes seen in severe coliform mastitis result from the effects of release of lipopolysaccharide (LPS) endotoxin from the bacteria and subsequent activation of cytokine and arachidonic acid–derived mediators of inflammation and the acute phase response.

Treatment of mastitis in cattle

• Treatment of endotoxin-induced shock with fluids, electrolytes, and anti-inflammatory drugs.

• Many cows with endotoxic shock are marginally hypocalcaemic; thus, 500 mL of calcium borogluconate should be administered SC.

• Oxytetracycline (11 mg/kg/day, IV), Ceftiofur sodium (2.2 mg/kg/day, IM)

• NSAIDs are widely used in treatment of acute mastitis.

• Flunixin meglumine, carprofen, ibuprofen, and ketoprofen can be used astreatments for coliform mastitis or endotoxin-induced mastitis.

• Pseudomonas aeruginosa, Trueperella pyogenes, Mycoplasma spp. less frequently cause cow mastitis.

Prevention of mastitis in cattle

• New infections caused by Strep. agalactiae and Staph. aureus can be prevented by focusing management efforts on milking technique and hygiene.

• Clean and dry bedding, clean and dry udders at the time of milking.

• The single most important management practice to prevent transmission of new infections is the use of an effective germicide as a post-milking teat dip.

• Dip (rather than a spray) immediately after milking.

• Use of individual towels for drying teats, gloves for milkers’ hands, use of a pre-milking germicide (spray or dip).

• Cleaning milking units after an infected cow has been milked.

• Routine milking equipment checking. Liners and rubber air hoses should be replaced as needed.

• Proper milking hygiene also reduces the new infection rate of noncontagious pathogens.

• For environmental pathogens, cows should be provided dry, clean housing.

Metritis and Endometritis in Large Animals

• In cows, the causative organisms are most often Trueperella pyogenes, alone or in association with Fusobacterium necrophorum or other Gram-negative anaerobic organisms.

• Signs of infection vary from obvious and persistent purulent exudate from the uterus to inapparent infection.

• Acute puerperal metritis responds well to systemic antimicrobial therapy combined, if necessary, with NSAIDs and other supportive measures such as fluid therapy.

• Cephalosporin antibiotics (cefalexin, ceftiofur) or aminopenicillins are considered most appropriate for systemic treatment of cows with metritis.

• Oxytetracycline requires administration at high levels (11 mg/kg, bid) to maintain uterine tissue concentrations of 5 mg/kg.

• Escherichia coli, Staphylococcus, Streptococcus, and Mycoplasma spp,

• Potentiated SA, fluoroquinolones

• Antibiotics should be selected on the basis of sensitivity testing and given for 3–4 wk.

• Enrofloxacin at a dosage of 5 mg/kg, bid, orally is a good empiric treatment choice while awaiting results of microbiologic testing.

Treatment of prostatitis

Sulfadiazine, Trimethoprim

The canine prostate gland commonly developsdiseases.Bacterial prostatitis, prostatic abscesses.

Age distribution of diarrhoeal diseases in pigs

Bacterial diseases Nursing Weaning Growing-finishing

Clostridium difficile +++ + +

C. perfringens, A ++ + -

C. perfringens, C ++ - -

Enteric colibacillosis +++ +++ -

Intestinal spirochaetosis - ++ +++

Proliferative enteritis - ++ +++

Salmonella enteritis + ++ +++

Swine dysentery + ++ +++

Clostridium enteritis in pigs

• Clostridium difficile is an important emerging pathogen that causes diarrhoeaprimarily in neonatal swine.

• The agent was first recognized as a cause of antibiotic-associated diarrhoea inpeople.

• It most commonly causes disease in piglets 1–7 days old and in other domesticand laboratory animals.

• Erythromycin, tetracycline, and tylosin may be useful for treatment of suckling piglets.

• Tiamulin and virginiamycin may help to reduce levels of the organism in adult swine.

Treatment of Swine Dysentery

• Bloody scours

• Swine dysentery is a severe, infectious disease characterized by mucohemorrhagic diarrhoea and marked inflammation limited to the large intestine (coecum and/or colon).

• It occurs at all ages, but more frequently in growing/finishing pigs.

• Brachyspira hyodysenteriae

• Therapeutic use of antibacterials is effective if started early. Water medication is preferred at first.

• Lincomycin, tylvalosin, tiamulin (treatment inj.), valnemulin commonly used.

Intestinal Salmonellosis in Pigs

• Enteropathogenic salmonellae cause inflammation and necrosis of the small and large intestines, resulting in diarrhoea that may be accompanied by generalized sepsis.

• All ages are susceptible, but the disease is most common in weaned and growing-finishing pigs.

• Salmonella choleraesuis

• Parenteral administration of antibacterials to acutely ill pigs and medication of the affected group via water or feed may decrease the severity of the outbreak.

• Neomycin and lincomycin-spectinomycin are the most often used water medications. Several other options possible (tetracyclines, aminopenicillines, quinolones, phenicols, SUA-TMP).

Neoiven, Neomay 500 000 IU/g Powder for Use in Drinking Water

Porcine Proliferative Enteritis

• Porcine proliferative enteritis is a common diarrheal disease of growing-finishing and young breeding pigs characterized by hyperplasia and inflammation of the ileum and colon.

• Lawsonia intracellularis, an intracellular, Gram-negative, small rod-shaped bacterium

• The more common, nonhemorrhagic form of the disease often affects18- to 36-kg pigs and is characterized by sudden onset of diarrhea. The feces are watery to pasty, brownish, or faintly blood stained.

• Most affected pigs recover spontaneously, but a significant number develop chronic necrotic enteritis with progressive emaciation. The hemorrhagic form is characterized by cutaneous pallor, weakness, and passage of hemorrhagic or black, tarry feces. Pregnant gilts may abort.

• Many antibiotics such as tiamulin, tylosin, tetracycline, lincomycin are documented to be effective at prophylactic doses to control L. intracellularisinfections.

• During clinical disease outbreaks, antibiotics such as tylosin, enrofloxacin, tetracyclines, tiamulin, and tilmicosin are commonly used at higher doses and are effective.

Bacterial Diarrhoea in Foals

• Bacterial enterocolitis in neonatal foals can be a component of neonatal septicaemia, and diarrhoea can be seen with bacteraemia of any cause.

• Salmonella spp., Escherichia coli, and Actinobacillus spp.

• Intensive antimicrobial treatment, correction of fluid loss and electrolyte abnormalities, and nursing care are needed.

• Rhodococcus equi can cause acute and chronic enteritis and can cause diarrhoea in foals 1–4 months old.

• Clarithromycin combined with rifampicin is the treatment of choice for R.equi infection in foals.

Bacterial Diarrhoea in Foals

• Other macrolides such as azithromycin or erythromycin can be used, but erythromycin can predispose to diarrhoea and hyperthermia.

• Enteric infection with Lawsonia intracellularis causes proliferativeenteropathy, resulting in outbreaks of diarrhoea, rapid weight loss, colic, lethargy, subcutaneous oedema, and protein-losing enteropathy in weanlingfoals.

• Treatment: oxytetracycline (6.6 mg/kg, IV, bid for 3–7 days) followed by doxycycline (10 mg/kg, bid for 14 days). COST-BENEFIT!

• Alternatives include erythromycin (alone or in combination with rifampicin) for 3–4 wk. or chloramphenicol (availability?).

Clostridia-associated Enterocolitis in Horses

• Clostridium difficile and C. perfringens are common causes of enterocolitis in horses and foals.

• Antimicrobial administration has been associated with C. difficile diarrhoea.

• Treatment with metronidazole (15–20 mg/kg, PO, tid-qid) appears to be beneficial intreating enteric clostridial infections.

• Polymyxin B may aid in binding systemic endotoxin.

• Continuous infusion of IV fluids and parenteral nutritional support is optimal.

• The yeast Saccharomyces boulardii has been shown to be protective in clostridialdiarrhoea in other species, and there is some evidence of beneficial effects in thetreatment of horses with colitis. It produces a protease that specifically degrades C. difficile toxins A and B.

• Orally administered DTO (Di-tri-octahedral) smectite powder also binds clostridialtoxins and may be useful in horses with diarrhoea.

Tyzzer Disease

• Tyzzer disease is an enterohepatic syndrome of a wide range of animals.

• Caused by Clostridium piliforme, a motile, sporeforming, rod-shaped, flagellated, obligate, intracellular bacterium.

• C. piliforme is sensitive to tetracycline and partially sensitive to streptomycin, erythromycin, penicillin, and chlortetracycline. It is resistant to sulfonamides and chloramphenicol.

• In neonatal foals, the disease seems to be nearly 100% fatal, although it is likely thatolder foals less severely affected may survive.

• A few presumptive cases of Tyzzer disease in foals have been treated successfully by intensive administration of IV dextrose, sodium bicarbonate, potassium chloride, penicillin, and sulfamethoxazole-trimethoprim.

• Reducing the nitrogenous dietary compounds, including protein and nitrate in the diet that may induce immunosuppression in neonatal foals, may lessen the incidence of the disease.

Salmonellosis

• Salmonellosis in warm-blooded vertebrates is in most cases associated with serovars of Salmonella enterica.

• Young calves, piglets, lambs, and foals may develop both the enteritis and septicaemic form.

• Adult cattle, sheep, and horses commonly develop acute enteritis, and chronic enteritis may develop in growing pigs and occasionally in cattle.

• Initial antimicrobial therapy should be based on knowledge of the drug resistance pattern of the organisms.

• Trimethoprim-sulfonamide combinations may be effective. Alternatives are bac- orpivampicillin, fluoroquinolones, or third-generation cephalosporins.

• Resistance to ampicillin, trimethoprim, sulfonamide, tetracyclines, andaminoglycosides is generally plasmid mediated and transfers readily between different bacteria.

• Resistance to quinolones is mutational, but random mutations may be selected by antibiotic use and may be transferred by bacteriophages.

• Treatment should be continued daily for up to 6 days.

Trimethoprim - Sulfadiazine

Enteric Campylobacteriosis

• Campylobacter spp. are spiral, microaerobic, Gram-negative bacteria that cause gastroenteritis in people and animals.

• C. jejuni jejuni, C. coli, C. jejuni, C. upsaliensis, and C. helveticushave been associated with intestinal disease in companion animals.

• In cattle and sheep, Campylobacter spp. can cause enteritis and abortion, including C. jejuni jejuni, C. fetus subsp. fetus, C. hyointestinalis subsp. hyointestinalis and C. sputorum.

• Pigs have anorexia, fever, and diarrhoea for 1–5 days followed by remission of clinical signs but continue to shed C. jejuni jejuni in the faeces. C. hyointestinalis hyointestinalis and C. mucosalis are also implicated as causes of enteritis in pigs.

• Birds, including intensively farmed poultry, appear to have a higher infection rate and carriage of Campylobacter spp., especially C. jejuni jejuni.

Enteric Campylobacteriosis

• Clindamycin, gentamicin, tetracyclines, erythromycin, cephalosporins, and fluoroquinolones are effective against C. jejuni, C. helveticus, and C. upsaliensis.

• C. fetus, C. hyointestinalis, C. mucosalis, and C. sputorum are usually resistant tothe fluoroquinolones yet sensitive to cephalosporins.

• C. coli is sensitive to fluoroquinolones but resistant to cephalosporins.

Chlortetracycline Hydrochloride

Meningitis, Encephalitis, and Encephalomyelitis

• Inflammation of the meninges (meningitis) and inflammation of the brain (encephalitis) are seen in animals and often manifest concurrently (meningoencephalitis).

• Causes of meningitis, encephalitis, and meningoencephalitis include bacteria, viruses, fungi, protozoa, rickettsia, parasite migrations, chemical agents, and idiopathic orimmune-mediated diseases.

• In ruminants, generally bacterial infections are more common than other causes of meningitis or encephalitis.

• In species other than ruminants, especially adult animals, viruses, protozoa, rickettsia, and fungi are as or more frequent causes of meningitis or encephalitis than are bacteria.

• Listeria monocytogenes is a common infection in cattle.

• Streptococcus equi equi is one of the most common causes of brain abscessation in horses, and Rhodococcus equi abscesses have been described in foals.

• Spontaneous bacterial meningitis or meningoencephalitis develops in dogs rarely, occurs more commonly in food animals, and is most common in septic neonatal animals.

Meningitis, Encephalitis, and Encephalomyelitis

• Various aerobic bacteria (Pasteurella multocida, Mannheimia haemolytica, Staphylococcus spp., Escherichia coli, Streptococcus spp., Actinomyces spp., and Nocardiaspp.)

• and anaerobic bacteria (Bacteroides spp., Peptostreptococcus anaerobius, Fusobacteriumspp., Eubacterium spp., and Propionibacterium spp.) have been isolated from animalinfections.

• Appropriate use of antibiotics, according to culture or serology results, is basic to successful therapy.

• Broad-spectrum antibacterials that can penetrate the blood-brain barrier should be selected, and bactericidal drugs are preferred over bacteriostatic agents.

• Recommended drugs include ampicillin, metronidazole, tetracyclines, potentiated sulfonamides, fluoroquinolones, and third-generation cephalosporins; higher than normal dosages may be necessary to achieve and maintain adequate concentrations in the CNS.

Treatment of dermatophytosis

• In dogs, ~70% of cases are caused by Microsporum canis, 20% by M. gypseum, and 10%by Trichophyton mentagrophytes;

• In cats, 98% are caused by M. canis.

• Dermatophytosis in dogs and shorthaired cats may be self-limiting.

• Whole-body topical therapy fasten the clinical cure and decrease environmentalcontamination.

• Whole-body lime sulfur dips (1:16), 0.2% enilconazole rinses, 2% miconazole, and a combined 2% miconazole/chlorhexidine shampoo were found to be antifungal.

• Local lesions can be treated effectively with topical miconazole or clotrimazole.

Chlorhexidine Gluconate, Miconazole Nitrate

enilconazole

Treatment of dermatophytosis

• Systemic treatment: chronic or severe cases and ringworm in longhaired cat breeds and Yorkshire terriers.

• Itraconazole, fluconazole, terbinafine, ketoconazole, and griseofulvin.

• The microsized formulation of griseofulvin in dogs: 25–100 mg/kg, daily or in divided doses

• - in cats: 25–50 mg/kg, daily in divided doses

• - it is best absorbed when given with fatty meal.

• Or itraconazole: 5–10 mg/kg/day, or pulse therapy 5–10 mg/kg/day for 28 days then on an alternate-week regimen: 1 week on, 1 week off,

• - ketoconazole: 5–10 mg/kg/day

• - terbinafine: 30–40 mg/kg/day

• - fluconazole: 5–10 mg/kg/day.

Grisol V Powder 7.5% w/w Oral Powder for horses

Treatment of dermatophytosis

• Trichophyton verrucosum is the usual cause of ringworm in cattle, but T.mentagrophytes, T. equinum, Microsporum gypseum, M. nanum, M. canis, and others have been isolated.

• Generalized skin disease may develop, but nonpruritic periocular lesions are most characteristic.

• Cows and heifers are reported to develop lesions on the chest and limbs most often, and bulls in the dewlap and intermaxillary skin.

• Spontaneous recovery is common.

• Valuable individual animals should still be treated, because this will limit both progression of existing lesions and spread to others in the herd.

• Thick crusts should be removed gently with a brush, and the material burned or disinfected with hypochlorite solution.

• Treatment: 4% lime sulfur, 0.5% sodium hypochlorite (1:10 household bleach), 0.5% chlorhexidine, 1% povidone-iodine, natamycin, and enilconazole.

• Individual lesions can be treated with miconazole or clotrimazole lotions.