Vaccination Part 2

Early feeding

Should occur within 12 hours after hatch.

Importance of early feeding

Critical for optimal growth and development during the first week.

Preferred feed particle size for chicks

Coarse particles.

Consequence of not eating during the first two days

Lower breast muscle percentage.

Recent genetic selection in broilers

Focused on increased breast meat yield.

Result of genetic improvement

Increased feed intake, growth rate, and feed efficiency.

Negative consequence of genetic gains

Increased risk of metabolic disorders.

Target body weight of layers at 18 weeks

1.3 kg.

Desired flock uniformity at 18 weeks

80%.

Target peak egg production of layers

93–96%.

Target hen-day eggs to 72 weeks

More than 305 eggs.

Target egg weight at 40 weeks

More than 62 g per egg.

Target egg mass to 72 weeks

20 kg.

Most important factor for peak production

Flock uniformity.

Method of checking flock uniformity

Birds should be within ±10% of average body weight.

Excellent flock uniformity

Greater than 85%.

Good flock uniformity

75–85%.

Poor flock uniformity

Less than 70%.

Benefits of uniform flocks

Higher egg production, better persistence, and improved feed conversion.

Macronutrients

Nutrients essential for growth, energy, and overall health.

Water

Critical nutrient involved in metabolism and nutrition.

Function of water in nutrient transport

Transports nutrients throughout the body.

Function of water in temperature regulation

Helps maintain normal body temperature.

Function of water in waste removal

Mobilizes metabolic waste products.

AMEn

Apparent metabolizable energy corrected for nitrogen balance.

Definition of AMEn

Difference between gross feed energy and energy lost in feces, urine, and gases.

First limiting amino acids in poultry diets

Methionine and cystine.

Reason methionine and cystine are limiting

Plant protein sources contain low levels of these amino acids.

Micronutrients

Nutrients required in small amounts for vital body functions.

Broiler nutrient requirements

Absolute nutrient requirements have changed little over the last 50 years.

Major focus of modern genetic selection

Faster growth and higher feed intake.

Basis of modern broiler nutrition

Balanced digestible amino acids, enzymes, and proper calcium-phosphorus ratios.

Cause of nutrient deficiencies

Erroneous feed formulation.

Another cause of nutrient deficiencies

Oxidation of nutrients.

Feed-related cause of nutrient deficiencies

Mold contamination and excess moisture.

Effect of low energy intake

Reduced growth rate.

Effect of low energy intake in mature birds

Weight loss and decreased egg production.

Effect of low energy intake in male breeders

Infertility.

Effect of low energy intake on disease resistance

Increased susceptibility to infections.

Lysine deficiency effect

Reduced growth rate and poorer feed conversion.

Methionine deficiency effect

Reduced growth rate.

Effect of amino acid deficiency in layers

Reduced egg size and egg number.

Vitamin A deficiency condition

Ataxia or nutritional roup.

Vitamin A deficiency eye lesion

Xerophthalmia.

Common name for xerophthalmia

Night blindness or dry eye.

Prevention of Vitamin A deficiency

Provide green forage, fruits, vegetables, and properly stored feed.

Vitamin A deficiency egg abnormality

Blood spots and meat spots.

Vitamin D deficiency disease

Rickets.

Vitamin E deficiency neurologic disease

Encephalomalacia.

Common name for encephalomalacia

Crazy chick disease.

Vitamin E deficiency muscular condition

Muscular dystrophy.

Prevention of Vitamin E deficiency

Use quality feed ingredients and proper storage.

Vitamin B deficiencies commonly discussed

Thiamine, riboflavin, pantothenic acid, and biotin deficiencies.

Factors affecting eggshell quality

Mineral imbalance, disease, heat stress, genetics, and age.

Minerals important for shell quality

Calcium, phosphorus, manganese, and vitamin D3.

Diseases that affect shell quality

Newcastle disease and infectious bronchitis.

Recommended calcium level for older laying hens

More than 4%.

Effect of aging on phosphorus requirement

Requirement decreases with age.

Sodium chloride function

Regulates electrolyte balance and osmotic pressure.

Recommended sodium chloride level

0.12–0.15% of the diet.

Effect of sodium chloride deficiency

Reduced growth and egg production.

Behavior associated with sodium chloride deficiency

Tail picking and cannibalism.

Zinc requirement of poultry

40 mg/kg of feed.

Effect of zinc deficiency

Poor feathering and reduced growth.

Characteristic lesion of zinc deficiency

Chondrodystrophy.

Manganese and choline deficiency disorder

Perosis.

Another name for perosis

Slipped tendon.

Definition of perosis

Displacement of the gastrocnemius tendon from the hock groove.

Diagnostic clue for certain poisonings

Fluorescence of blood under UV light.

Common source of lead poisoning

Paint and orchard-spray materials.

Lethal dose of metallic lead

7.2 mg/kg body weight.

Clinical sign of lead toxicity

Greenish droppings within 36 hours.

Major signs of lead poisoning

Depression, weakness, thirst, inappetence, and emaciation.

Necropsy finding in lead poisoning

Greenish-brown gizzard mucosa.

Organs commonly damaged by lead toxicity

Liver and kidneys.