Welfare of Pigs

Pig welfare is an important area of livestock production management because pigs are intensively reared, highly intelligent, and sensitive animals. Poor welfare can affect health, productivity, behavior, and meat quality.

a. Nutrition and Feeding

• Pigs require balanced diets with energy, protein, minerals, and vitamins.
• Feed restriction in sows is a welfare concern, often leading to hunger, frustration, and stereotypic behavior.
• Water must be available ad libitum, as pigs are very sensitive to dehydration.
• Welfare indicators: body condition score, feed intake, presence of stereotypies (bar biting, sham chewing).

b. Housing and Space

• Adequate space is necessary to avoid overcrowding, aggression, and tail biting.
• Flooring must be non-slippery and comfortable; slatted floors may cause injuries.
• Pigs prefer clean resting areas, separate from dunging and feeding zones.
• Welfare indicators: lying behavior, lesion prevalence, aggression levels.

c. Health and Disease Prevention

• Respiratory diseases (e.g., pneumonia, pleurisy) and enteric diseases are common welfare threats.
• Good biosecurity, vaccination, and hygiene are crucial.
• Lameness, skin lesions, and tail biting are major health-related concerns.
• Welfare indicators: morbidity, mortality, coughing, sneezing, veterinary records.

d. Environmental Management

• Pigs are very sensitive to temperature extremes.
• Heat stress leads to reduced feed intake, slower growth, and high mortality.
• Cold stress causes shivering, piling, and increased disease susceptibility.
• Proper ventilation reduces respiratory disease and ammonia build-up.
• Welfare indicators: panting, piling, rectal temperature, growth performance.

e. Behavior and Enrichment

• Pigs are highly curious and exploratory by nature.
• Lack of enrichment leads to abnormal behaviors such as tail biting, ear biting, and bar biting.
• Provision of straw, manipulable materials, and rooting substrates improves welfare.
• Welfare indicators: frequency of abnormal behavior, play behavior, social interactions.

f. Breeding and Reproduction

• Sows confined in gestation crates (stalls) suffer from severe movement restriction and stress.
• Farrowing crates restrict maternal behavior, although they reduce piglet crushing.
• Alternative systems (loose housing, group housing of sows) improve welfare.
• Welfare indicators: reproductive performance, piglet mortality, sow behavior.

g. Painful Husbandry Procedures

• Common practices include tail docking, teeth clipping, ear notching, and castration.
• These procedures cause pain, stress, and risk of infection if performed without anesthesia.

Welfare-friendly alternatives:

• Use of analgesics/anesthetics.
• Genetic selection for reduced aggression/tail biting.

Indicators: vocalization, cortisol levels, wound healing.

h. Transport and Slaughter

• Transport causes stress due to mixing, overcrowding, noise, heat, and dehydration.
• Rough handling increases fear, injuries, and mortality (dead-on-arrival pigs).
• Proper stunning before slaughter is critical to minimize suffering.
• Welfare indicators: mortality during transport, injury rates, meat quality (PSE meat – Pale, Soft, Exudative).