Theory question 107
Poultry Production(a)(i) What is incubation in poultry production? (ii) State two advantages and two disadvantages of natural incubation.
(b) List four factors that affect pasture establishment in West Africa.
(c) In a tabular form, state the causal organism and two symptoms of each of the following diseases of farm animals: (i) Brucellosis; (ii) Newcastle.
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(a)(i) Incubation is keeping fertile eggs at the right temperature, humidity and turning until they hatch, either under a broody hen or in an incubator.
(ii) Advantages: cheap, no equipment; hen turns eggs and gives correct heat and humidity; hen broods chicks after hatching. Disadvantages: few eggs at a time; hen stops laying while sitting; hen may desert eggs; diseases can pass from hen to chicks; hatching depends on hen's broodiness.
(b) Any four: rainfall; soil fertility; land preparation/seedbed; choice of species/seed quality; time of planting; weeds; pests and diseases; grazing management/fire.
(c) Table: Brucellosis – causal organism: bacterium Brucella abortus (cattle)/B. melitensis; symptoms: abortion in late pregnancy, retained placenta, infertility, swollen joints/testes. Newcastle – causal organism: virus (Newcastle disease virus/paramyxovirus); symptoms: gasping and coughing, greenish diarrhoea, twisting of neck/paralysis, drop in egg production, sudden death.
Set (c) out in a table with columns for disease, cause and symptoms.