Environmental impact of pig production and ways to reduce it
OPTIMIZATION OF SWINE PRODUCTION
The global increase of meat production and farms intensification have led to a greater pressure on producers to reduce the environmental impact of animal production. In pig farming, the main elements contributing to environmental pollution are nitrogen and phosphorus.
Image 1. Meat production, trends and forecast, in million tones (The Meat Atlas by H. Böll).
The knowledge causes for environmental pollution in pig farming is the clue to understand the mechanisms to diminish it. Such causes can be summarized as:
- Improper installations (smells and gases)
- Improper excreta and sewage handling
- Excessive excretion of the diet’s nitrogen, and the release of ammonia to the atmosphere
- Excessive excretion of phosphorus and other minerals in the diet
Therefore, there are to major mechanisms to reduce the environmental impact of pig production:
- Production optimization
- Diet optimization
A) PRODUCTION OPTIMIZATION
The relationship between the environmental impact and the production system’s efficiency is clear: greater efficiency leads to greater utilization of the resources and less production residues. Thus, optimizing growth parameters is essential to reduce the days in the farm per animal, the resources and the excreta.
Optimizing the installations and housing is also essential to reduce the need for heating systems and the production of bad smells and gases. A proper handling and treatment of liquid manure and slurry is just as important to achieve a lower environmental impact.
The global increase of meat production and farms’ intensification have led to a greater pressure on producers to reduce the environmental impact of animal production. In pig farming, the main elements contributing to environmental pollution are nitrogen and phosphorus.
Graph 1. Relationship between nitrogen requirements and the number of feeding phases in pig production (Jongbloed et al., 1998).
Graph 2. Phosphorus deposition curve in growing pigs (Jongbloed et al., 1998).
Despite this fact, adjusting minerals supply (especially phosphorus) to animal requirements is often complex due to the use of premixes that don’t allow the individual quantification of their ingredients. Moreover, there is a high level of uncertainty regarding the mineral supply of the raw materials because of the lack of analytic information, which leads to an excessive mineral supplementation.
B) Diet optimization
B.2.) Improvement of feed utilization
B.2.1. Using a highly bioavailable mineral source to supply the mineral requirements of pigs.
B.2.2. Improving mineral utilization via enzymes: phytase is an enzyme that increases phosphorus and other minerals bioavailability by increasing phosphorus release associated to phytic acid in the ingredients of the diet.
Phosphorus has a significant environmental impact in intensive production systems located in specific geographic zones (see image 2). This element reaches aquatic ecosystems by runoff, causing eutrophication and the misbalance of the ecosystem.
Image 2. Pigs density map (number/km2) (FAO).
B.2.3. Utilization of pronutrients:
B.2.3.1. Utilization of Improvers of the Mineral Absorption: natural products that allow a greater utilization of minerals in the diet. They’re based on pronutrients, active molecules from a botanical origin that improve the animal’s physiology. Pronutrients that are improvers of the mineral absorption are the ones acting on enterocytes, promoting its physiological function and the absorption of minerals from the diet.
B.2.3.2. Utilization of Intestinal Conditioners: they’re also natural products based on pronutrients, but, in this case, they promote the regeneration of the intestinal mucosa. When farm animals are fed pronutrients, their intestinal mucosa regenerates faster (at a physiologic rate) and is renewed, so that digestion and nutrients absorption are optimized (there’s a better diet utilization).
In the table below there are the results of a trial carried out in an experimental farm where the use of Intestinal Conditioners (without AGPs) was compared with a control group (no pronutrients, but with AGPs) in broilers until 35 days of life:
|WITH INTESTINAL CONDITIONERS
WITHOUT INTESTINAL CONDITIONERS
Live weight (g)
Feed Conversion Rate
% of breast
The use of these natural additives helps to reduce the mineral supply from the diet, since they a greater percentage of them will be used by the animals (less natural resources will be used), and to reduce their excretion (less environmental impact).
MV. Júlia Pié Orpí
Veterinary Technical support to the area of Latin America at Biovet S.A. Laboratories Official Veterinary Services (SVO) in poultry slaughterhouse