Babesiosis/ Texas Cattle Fever/ Red Water Fever (A disease caused by Unicellular Blood Protozoan)

 

Babesiosis/ Texas Cattle Fever/ Red Water Fever

Introduction:

Unicellular Blood Protozoan that requires vector for its transmission i.e. Ticks (Boophilus microphilis or Riphicephalus). Caused by Babesia bovis, B. bigemina, and B. divergens in cattle and by B. ovis and B. motasi in sheep.

B. bovis is transmitted by the larval stage of these ticks and B. bigemina by nymphal stage of ticks.

Occurrence:

Seasonal or in summer or rainfall season and when there is a prevalence of ticks.

Pathogenesis:

Tick bite results in entry of babesia into the body of host that damage the peripheral and visceral vessels + erythrocytes and cause icterus, anemia and hemoglobin urea (characteristic feature) that’s why known as red water disease. B. divergens lead to subacute and persistent fever and B. bovis leads to fatal thrombosis and death of an animal in addition to that bovis release inflammatory mediators that cause vasodilation and result in hypotension.

Clinical Findings: (Incubation period 2-3 weeks)

Acute onset of fever (104°- 107° F), anorexia, depression, weakness, fall in blood pressure, ruminal stenosis, tachycardia and tachypnea due to breakdown of RBC's. Initially, the conjunctiva is brick red but later it becomes pale due to the break down of RBCs. There are hemoglobin urea and animal pass brick red or brownish urine. Other signs are diarrhea and later on constipation. Abortion may occur in pregnant animals.

Differential Diagnosis:

Differentiated with those conditions in which Hemoglobin urea and anemia occur.

Pre-parturient Hemoglobin urea: occur due to Phosphorus deficiency near parturition, mostly in winter season or due to brassica eating.

Thileria: The long incubation period, sub-acute

Bacillary hemoglobin urea: Highly acute, severe toxemia, acute signs, no blood cells in urine.

Hemonchosis: Jaundice, anemia without Hgurea.

Leptospirosis: More in dogs, transient fever, no Hemoglobin urea.

Treatment:

Imidocarb dipropionate, Diaminazine diaceturate 3.5mg/kg Bid or 12 mg/kg single dose IM, B-complex in combination with liver tonic

Control:

Eradicated by eliminating the ticks. Treat cattle’s every two to three weeks with acaricides.

Aspergillosis/Mycotic pneumonia (An acute and chronic disease of birds)

 

       Aspergillosis/Mycotic pneumonia

Etiology:

Aspergillus fumigatus

It is an acute and chronic disease of birds. It was first reported in ducks in 1833 and 1898 in Turkey. It is transferred from hatchery through contaminated soil and penetrates the eggs. Mostly occur in immunosuppressant birds. When there is high ammonia then it causes spores to germinate.

Route of infection:

1.       Inhalation

2.       Contaminated feed

3.       Litter

Clinical findings:

·         Dyspnea

·         Gasping

·         Cyanosis of comb and wattles

·         Dehydration

·         Diarrhea

·         Polydipsia

·    Sometimes nervous signs also appear like ataxia, falling of birds, Pushing over backward, Opisthotonous

Postmortem findings:

·         Bluish, greenish and blackish layer on air sacs when body opened

·         Yellowish or grey nodules may present on lungs

Diagnosis:

·         Hyphae saw under microscope

·         Lesions have leathery appearance

·         Immunosuppression by the spores

·         Spores present

·         Systemic and visceral involvement

·         Respiratory signs

·         Peritoneum and gizzard effected

Treatment:

·         Nystatin

·         Amphotericin B

·         Ketoconazole

·         Fluconazole

·         Miconazole

·         Broad-spectrum antibiotics to avoid secondary infection

·         Disinfection with CuSo4

Control

·         Improve husbandry and management practices

·         Frequently replace the litter and disinfection of shed

·         Spores are in eggs, so eggs are also disinfected or mostly discarded

Actinobacillosis (A disease of non-motile, gram-negative, rod-shaped bacteria)

 

Actinobacillosis

Etiology:

Actinobacillus species are non-motile, gram-negative, rod-shaped bacteria.

These are facultative anaerobes.

Most species are oxidase-positive and produce urease.

Species of veterinary importance grow on MacConkey agar.

Actinobacillus lingnieresii cause a lesion in the tongue, lymph nodes, ruminal wall, and skin in cattle.

It is a common inhabitant of the oral cavity which needs wound or laceration for entry to cause disease.

Pathogenesis:

Bacteria enter through the wound and cause acute infection at the local site, there is granulomatous lesion formation with pus discharge, there is the involvement of regional lymph nodes (parotid, lingual and retropharyngeal). If lesions break under the tongue, the pus goes down and cause visceral infection.

In actinomycosis, there is no involvement of lymph nodes while in the case of actinobacillosis, there is involvement of soft tissue.

Clinical Findings:

Acute inflammation of tongue called glossitis.

Difficulty in prehension and chewing.

Excessive salivation.

Animals become anorexic for 24-48 hrs.

On palpation, swelling is painful and is present mostly on the base of the tongue. There is formation of nodules and ulcers on the dorsum and lateral side of the tongue.

In chronic cases, there is fibrosis of tongue and its size shrink.

The tongue becomes immovable.

There is inflammation of submaxillary and parotid lymph nodes thus causing difficulty in swelling.

It is pyogranulomatous lymphadenitis, and when these granules rupture pus run down and infects the viscera.

There are nasal discharge and snoring sounds when maxillary lymph nodes are involved.

Granulomatous lesions develop on external nares, the skin around the nostrils, and on eyelids as well.

In sheep, there is less involvement of the tongue, the formation of a granulomatous lesion on the face, lower jaw, from nostrils to the sternum.

Size of granules is about 8 cm,

There is cranial and cervical lymph node enlargement,

Yellowish green pus discharge occurs,

Difficulty in mastication,

Scabs around lips,

Bilateral nasal discharge and cud dropping.

Treatment:

Potassium iodide is given per oral; 6-10g daily for 7-10 days in cattle.

Sodium iodide @1g/12kg body weight as 10% solution is injected IV, single dose enough for soft tissue.

If hard tissue is also involved e.g. in case of actinomycosis, repeat the dose after 15 days.

If there is a high dose, this causes iodine toxicity which may lead to lacrimation, anorexia, abortion, coughing, dyspnea, tachycardia, and staggering.

In sheep, a 20 ml solution of sodium iodide 10% sub-cut is given for 4-5 weeks.

Streptomycin and penicillin the combination is given; 1 g in small animals and 5 g in large animals.

Iodine also causes infertility i.e. chemical neutering so it should be used more carefully.

Rabies (Disease of all warm-blooded animals)

Rabies

Disease of all warm-blooded animals

Etiology:

·        Rabdoviridae/Genus/Lysa Virus

Clinical Importance:

·        Zoonotic and acute type of encephalomyelitis

Characteristics of Virus:

·        Bullet shaped

·        RNA

·        Capsid Proteins

·        Surface glycopeptide serve as a neurotoxin for this virus, its helps to enter virus in nerves due to presence of surface glycopeptide receptor on nerves (Lipid receptors)

Transmission:

·      Always through bite of infected or carrier animal

·     Mainly dogs, wild carnivores particularly foxes, racoons are important while rodents (rate bite in KPK) and bats (not common in our area, Important in America and African continents)

·     Saliva is rich in rabies virus

·  Its present in world wide but countries are considered rabies free like Australia, New-zeland, Norway, England and Sweden.

Pathogenesis:

·        Virus enters through bite (Saliva inject virus)

·        Initial replication occurs in local tissues

·        Virus reaches at neuromuscular junction

·    Enter into peripheral nerves, from nerves travel in axons via retrograde manner and then reach spinal cord and brain affected (Specially forebrain), then moves centrifugally through trigeminal nerve (Cranial Nerve) to salivary gland and comes in saliva. (Rabies also occur through wound, where dog lick, cats pawing on skin and has licking habit, In USA cats are major carrier)

·  Bats which cause rabies not in Pakistan, vampire virus responsible transmission of this disease in nerves.

Incubation period vary depends upon;

·        Distance from site of bite

·        Intensity of innervation

·        Amount of virus in inoculum

·       Speed of rabies in nerves is 100mm/day, if area more nervated then speed is 400mm/day.

·        No aerosol transmission

·      Rabies 2^nd name is death because when virus enter in nerves then there is no recovery

·      Negri bodies formed in brain

• Before appearing nerves signs, virus began to shed from saliva

Clinical Findings:

·        Clinically course 3-10 days

·        Incubation period is 4-24 weeks in dogs, 2-6 weeks in cats, years in human (up to 17 years)

·        Acute behavioral changes

·        Sudden onset of anorexia (esophageal obstruction leads to drooling of saliva)

·        Nervousness

·        Hyperexcitability

·        Changes in temperament

·        All above signs in esophageal shocking but not enter mouth of animal

Phases:

1.     Prodromal

2.     Dumb/Paralytic

3.     Furious

Prodromal Phase:

·        Nervousness

·        Anxiety

·        Variable fever

·        Erratic behavior

·        Loneliness and solitude

·        Corneal and palpebral reflexes are very slow

·        Pupillary dilation

·   Licking at site of wound (If excessive chewing either self-mutilation in rabies)

Furious Form:

·        Vigor in movement and forebrain effected

·        Incubation period is 2-4 days

·        Restlessness

·        Irritated behavior

• Include auditory and visual response

Photophobia:

·        Hyperexcitation

·        Barking at inanimate objects and pica like behavior

·        Muscular incoordination

·        Seizure and death

Paralytic/dumb form:

·        Incubation period is 2-4 days

·        Whole nervous system involved

·    Progressive motor lower nerve paralysis (ascending paralysis). It starts where bite, limbs and head paralysis

·        Laryngeal paralysis which leads to horror sounds

·        Dyspnea due to laryngealparalysis

·        Change in bark, hoarse sound due to laryngealparalysis

·        Pharyngeal paralysis leading to hypersalivation and dysphagia

·        Lockjaw

·        Masticatory paralysis or dropped jaw

·        Paralysis of respiratory muscles and cause comma and death

·       In cattle there is frequent urination and bellowing which is confused with estrous. In estrous not continuous bellowing, in paralysis continuously and sounds heavy

Diagnosis:

·        Case history

·        Stole test in which Fluorescent Ab technique is used (standard test)

·        In cats there is hyperexcitation and no carrier stage

Treatment:

·        No treatment, prophylactic vaccine, canvac, Rabisin and hexadoy

·        First vaccine at day zero- post exposure

·        If mother vaccinated, then 6th week pup

·        At 4 weeks age, first deworming then first shot after 3 weeks, 2nd shot. 6, 9, 12th and15th week then annual booster which depends on manufacturer

·        3 weeks 3 months, annual+ then 3 years in book

·        Serological titer does not show complete protection

Post exposure or of vaccinated:

·        Day zero            1 ml s/c

·        Day 7                  1ml s/c

In Non-vaccinated:

·        Zero-day             1ml S.c

·        7-day                   1ml S.c

·        14-day                 1ml S.c

·        21-day                1ml S.c

·        28-day                 1ml S.c

 

·        In buffalo: 4ml, 2cc IM, 2cc s/c, 7, 14, 21 days 3ml each

·        In horse: 3ml initially and then 2,2 ml

·  IGs and vaccine must be given, after exposure 2-8 weeks disease disappear

·     In vaccine 3 weeks takes for Abs, so no immediate treatment; so, IGs given but not available so keep it under observation. If behavioral abnormality then euthanizes it immediately

·        In humans: 5 injections, only 18% chances of death if vaccinated

·        In donkey, if dog bite then rabies occurs