INTRODUCTION TO LIVESTOCK HEALTH

INTRODUCTION TO LIVESTOCK HEALTH

INTRODUCTION TO LIVESTOCK HEALTH,Health. State in which all the body organs or parts and systems are functioning normally.

Disease. Deviation/alteration in state of the body or its organs that interrupts the proper performance of its functions.

Importance of keeping livestock healthy.

1. Healthy animals grow well and fast enough to reach maturity quickly.
2. Good health gives animals a longer productive life.
3. Healthy animals give maximum production or performance, i.e. they maintain high productivity.
4. Healthy animals produce good quality products that command a high market value.
5. Healthy animals will not spread diseases to either animals or human beings.
6. Healthy animals are economical to keep as the farmer spends less money on disease treatment hence reduction of production cost.

Signs of good health in livestock.

• Physical appearance.
• Physiological body functions.
• Morphological conditions of the body.

Physical appearance.

1. Behaviour of the animal. A healthy animal should be gentle/docile and produce normal sound.  Abnormal sounds aggression and over excitement indicate ill-health.
2. General appearance of the animal. Should be alert, bright in manner and able to carry its weight evenly.  Should also be responsive to touch.  Dull eyes and restlessness indicate ill health.
3. Movement of the animal. Should have normal gait and walk with ease.  Limping or straining while walking could indicate ill-health.
4. Should have an easy and normal posture both while standing or lying down.

Physiological body functions.

1. Appetite and feeding. Appetite is the desire of the animal to have food.  Loss or excessive appetite indicates ill-health.
2. Should defecate normally and regularly.  Inconsistency in texture, colour, smell and frequency of defecation indicate ill health.  Dung containing eggs, larvae of parasites or blood stains indicate ill health.
3. Should show regularly and normal urination.  Urine should be pale-straw in colour and takes place as fast as possible.  Difficulties in urination, abnormal colour e.g. red or heavy yellow indicates ill-health.
4. Body temperature. Should be within the normal range.  Temperature of blood is taken by clinical/veterinary thermometer inserted in the rectum of animals or under the wings for birds.
5. Respiratory rate. Should have a normal respiratory rate per minute.  Measured using a respirometer.

Factors influencing rate of respiration.

• Body size of the animal.
• Amount of exercise done by the animal.
• The degree of excitement.
• Ambient/environment temperatures.

Difficult and faster breathing indicates ill-heath.

1. Pulse rate. Should have a normal pulse rate. Pulse rate is the wave of blood passing through the arterial blood stream corresponding to beats of the heart.

INTRODUCTION TO LIVESTOCK HEALTH

Factors influencing pulse rate.

• Degree of excitement.
• Age of the animal.
• Sex of the animal.
• Physiological status of the animal e.g. pregnancy.

1. Production level of the animal. Producing animals should have a steady yield. On the other hand young growing animals should steadily gain weight or increase in size.  Loss of weight, emaciation and reduced production are signs of ill-health.

Morphological conditions of the animals body.

1. Visible mucus membrane. Should be pink in colour, moist, soft and elastic, smooth and well lubricated.  Sick animals the mucous membrane turns bright red, pale and anaemic yellow or bluish.
2. The skin and animal`s coat. Skin should be warm to touch smooth, pliable and moist especially around the muzzle.  Extreme dry hair or staring coat, excessive sweating, loss if hair, swellings on the skin, boils, and presence of parasites are signs of ill-health.

PRE-DISPOSING FACTORS OF LIVESTOCK DISEASES.

Pre-disposing factors.

Conditions inside or outside the body of an animal that lead to an animal contracting a disease or injury.

Include.

1. Species of the animal. g. swine fever attacks only pigs and Newcastle affect only poultry.
2. Breed of the animal. g. cancer of the eye will affect only Hereford breed of cattle and solar erythema affects only large white breed of pigs.
3. Age of the animal. Certain disease are associated with animals of a certain age group. E.g.

• Piglet anaemia-piglets
• Lamb dysentery-lambs
• Calf pneumonia-calves.

4. Sex of the animal. Certain diseases are associated with the sex of the animal.

• Orchitis –male animals.
• Vaginitis- female animals.
• Mastitis-lactating female animals.

5. Colour of the animal. Animals which are black may suffer from heat stress.  Animals with a light skin may suffer from diseases like photosensitisation when exposed to high light intensity e.g. solar erythema in large white pigs. 

INTRODUCTION TO LIVESTOCK HEALTH

CAUSES OF LIVESTOCK DISEASES.

1. Nutritional causes.

Metabolic disorders arise from malfunction within the body.

Deficiency of some minerals in the body may cause nutritional disorders.

Examples of nutritional disorders in livestock.

• Anaemia in piglets due to iron deficiency.
• Curled toe paralysis in poultry due to calcium and phosphorus deficiency.
• Milk fever (Parturient paresis) in lactating dairy animals due to deficiency in calcium.
• Goitre in calves due to iodine deficiency.
• Enzootic ataxia/swayback in lambs due to impaired metabolism of CHO and volatile fatty acids.
• Osteomalacia due to phosphorus deficiency.

2. Amount of food eaten by the animal.

Excessive intake of lush pastures causes bloat/ruminal tympany that is, production of excess methane in rumen during fermentation.

Excess food intake in mono-gastric may cause raptured stomach, diarrhoea or constipation.

3. Physical causes.

Physical injuries to body organs or parts.

Application of pressure for a long period e.g. a rope on the neck can cause physical injury that may block breathing tube or blood vessels.

Application of excess heat may cause blisters or burns.

Obstruction of hollow organs of the body may be considered as physical injury.

4. Chemical causes.

Poison.  Substance that interferes with normal structure or physiological mechanism of an animal’s body.

E.g.  Acids, alkalis, insecticides and herbicides.

Chemicals may also interfere with the permeability of membranes.

Stings from certain insects causes swellings and irritation.

Ingestion of some poisonous weeds e.g. Thorn apple (Datura stramonium)

5. Living organisms.

Includes: Bacteria, Protozoa, Virus, Worms, and insects.

Divided into two

1. Infectious disease causing organisms.
2. Parasitic living organisms.

Infectious disease causing organisms.

They are microscopic.  Include: Bacteria, Viruses and Protozoa.

Bacteria.

Unicellular microorganisms that occur in various shapes.

Shapes.

Pathogenic bacteria’s cause disease in livestock.

Table showing some of the bacterial diseases of livestock.

INTRODUCTION TO LIVESTOCK HEALTH

Viruses.

Contain a nucleic acid and a protein coat (DNA or RNA group.) requires an electronic microscope to view.  Grow and multiply only in living cells of other organisms.  Reproduce rapidly leading to death of the cells.  Viruses are host specific.  Viral diseases are very contagious and highly infectious.

 Table showing some of the viral diseases of livestock.

Protozoans.

Microscopic single-celled organisms.  May be pathogenic, parasitic or free living.

They are spread by arthropod vectors.

Table showing some of the protozoan diseases that attack livestock.

Parasitic organisms.

They suck blood, transmit other organisms that cause disease.  They block internal organs in the animal and cause injuries to the body.  They can be internal or external.

General methods of disease control.

Ø Routine management practises. Ø Preventive measures.             

1. Routine management practices.
2. Proper feeding.

Proper feeding makes animals strong and able to resist disease attack.  Well balanced ratio acts as a measure of preventing nutritional or metabolic disorders.  Actively growing animals should be supplied with ration high in protein to help in developing disease resistance.

2. Proper breeding and selection.

Select healthy animals for breeding.  They should be free or resistance to prevalent diseases.  Cull animals susceptible or those that are chronically ill.

3. Proper housing and hygiene.

Houses should be:

• Well ventilated but draught free.
• Provide adequate space to avoid overcrowding.
• Allow for proper drainage.
• Be leak proof.
• Lit and easy to clean.

1. Preventive measures.

1. Isolation of sick animals.

Separation and confinement of a sick animal from the healthy6 one.

It avoids spread of disease especially highly infectious and contagious diseases.

2. Imposition of a quarantine.

Restriction of movement of animals and their products from and into the affected regions in the event of an outbreak of a notifiable disease.

Notifiable diseases. Disease whose outbreak must be reported to a government authority.

Quarantine is based on the principle of enclosure where affected animals are enclosed and their movement restricted.

3. Prophylactic measures and treatment.

Taking prophylactic measures.   Control of diseases and parasites using preventive drugs.

Includes:

1. Use of prophylactic drugs. g. use of coccidiostat in water/food in poultry to control coccidiosis.   Drenching animals with antiheliminthes to control internal parasite.

Use of sulphonamides drugs to control Nagana.

2. Regular vaccination.

Boosting the immunity of animals.  Vaccines contain weakened or killed pathogens.

3. Control of vectors.

Vector is an organism that transmit disease from infected to healthy animals.

4. Treatment of the sick.

Restores the health of the animal and more importantly prevents spread of the disease.

5. Slaughtering affected animals.

Isolate and slaughter all infected animals to prevent further spread of the diseases.   Dispose the carcases by burning or burying deeply.  For highly infectious and contagious diseases e.g. swine fever, Newcastle, FMD.

6. Use of antiseptics and disinfectants.

• Preparations of mild anti bacteria drugs for use on skin or in wound.  Contains pathogen-killing agents.
• Used to kill bacteria’s on farm structures.   Contain germicidal chemicals e.g. phenol.

INTRODUCTION TO LIVESTOCK HEALTH

Appropriate methods of handling livestock.

Reasons/cases requiring handling of livestock

• When inspecting the animal to ascertain any abnormality or signs of disease.
• When administering any form of treatment to the animal.
• When spraying or hand dressing animals to control external parasites.
• When performing routine management practices e.g. dehorning, castration, hoof trimming.

Methods of handling.

• Halters
• Ropers
• Bull ring and lead stick.
• Crush
• Use of head yoke.

 Activities necessitating handling livestock in livestock health. 

1. Drenching

Oral administration of drugs to the animal.

Procedure.

• Restrain the animal in a crush.
• Measure the right dose into the drenching gun.
• Hold the head close to and under the left hand arm pit.
• Open the mouth with the left hand and insert the drenching gun to the mouth and let the animal swallow the dose slowly until the dose is over. Ø Release the animal.

2. Injection

Drugs are injected into the muscles (intra-muscular) or into the veins (intra-venous)

3. Hand spraying.

All sites preferred by ticks should be given special attention.

4. Mastitis control.

Restrain the animal in a crush.  Complete milking is done and thereafter, antibiotics are infused into the teats.

INTRODUCTION TO LIVESTOCK HEALTH

ALL AGRICULTURENOTES FORM 1-4 WITH TOPICAL QUESTIONS & ANSWERS

PRIMARY NOTES, SCHEMES OF WORK AND EXAMINATIONS