Nursery Pig Welfare: Post-Weaning Health and Management

Welfare in the Nursery Phase

The nursery phase — covering pigs from weaning (typically 3-4 weeks of age) to approximately 30 kg body weight — is one of the most challenging welfare periods in commercial pig production. Abrupt weaning creates multiple simultaneous stressors that compromise immune function, gut health, and behaviour, resulting in high disease incidence and significant welfare cost if not managed carefully.

The Post-Weaning Stress Cascade

At weaning, piglets simultaneously experience: separation from the sow (social and emotional stress), removal from the farrowing environment (environmental stress), dietary transition from milk to solid feed (nutritional stress), and mixing with unfamiliar pigs (social hierarchy disruption). These combined stressors cause immunosuppression, intestinal villous atrophy, and create ideal conditions for disease establishment.

Post-Weaning Diarrhoea (PWD)

PWD — predominantly caused by enterotoxigenic E. coli (ETEC) — is the most significant welfare disease of nursery pigs. Villous atrophy reduces absorptive capacity; ETEC toxins cause secretory diarrhoea leading to dehydration, weight loss, and death. Prophylactic zinc oxide (at pharmacological doses) has been widely used to prevent PWD but is being phased out in the EU due to environmental concerns, requiring alternative management strategies.

Alternatives to zinc oxide for PWD prevention include: acidifiers in water/feed, medium-chain fatty acids, organic acids, vaccination of sows (pre-farrowing F4/F18 vaccines), copper supplementation, and improved management reducing stress at weaning.

Nutrition and Feeding Management

Pre-starter diets (highly digestible, palatable feeds including milk products, fishmeal, and cooked cereals) bridge the dietary transition from milk to conventional pig feed. Palatability is critical — newly weaned pigs often don't eat for 24-48 hours post-weaning, causing hypoglycaemia and further immunosuppression. Multiple small meals, wet feeding, and highly palatable diets encourage early feed intake.

Environmental Conditions

Newly weaned pigs require environmental temperatures of 28-30°C — higher than older pigs — due to their limited thermoregulatory capacity and reduced fat reserves. Chilling dramatically increases PWD susceptibility and mortality. Solid floors with deep straw bedding or quality rubber mats, along with supplementary heat (heat lamps, heated flooring), maintain comfort.

Social Management

Post-weaning mixing creates fighting to establish dominance hierarchies. Best practice involves maintaining litter groups where possible, limiting group size to 8-12 pigs for the initial post-weaning period, providing additional space and enrichment during the high-risk first 48 hours, and monitoring for bullying and identifying victims early.

Behaviour and Enrichment

Nursery pigs without enrichment show increased redirected oral behaviours including tail biting, flank biting, and ear biting. Provision of rooting and foraging substrates (straw, corn stalks, paper) significantly reduces these welfare-compromising behaviours. Multiple feeding stations reduce competition stress during the critical post-weaning period.

This page is part of the Animal Welfare Hub — providing evidence-based information to improve the lives of animals. Return to home.