Polybrominated biphenyl (PBB) in the growing pig diet

Area of Science:

• Animal Science
• Toxicology
• Environmental Health

Background:

• Polybrominated biphenyls (PBBs) are persistent organic pollutants with potential toxic effects.
• Understanding the impact of PBBs on livestock health and productivity is crucial for food safety and agricultural practices.

Purpose of the Study:

• To evaluate the effects of dietary polybrominated biphenyls (PBBs) on growth performance, blood parameters, organ weights, and tissue alterations in pigs.
• To assess the reversibility of PBBs toxicity by observing pigs after dietary PBB withdrawal.

Main Methods:

• A 16-week growth trial involving twelve pigs fed diets with 0, 20, or 200 ppm of PBBs.
• Biweekly blood sampling for hematological and biochemical analyses.
• Post-trial examination of organ weights and gross pathology.
• A follow-up study involving PBB withdrawal to assess recovery.

Main Results:

• Pigs fed PBBs exhibited significantly reduced average daily gain and feed intake, with feed/gain ratios increasing with PBB levels.
• Reduced hemoglobin and hematocrit were observed at 6 weeks in the 200 ppm PBB group.
• Liver, heart, kidney, and adrenal weights increased significantly as a percentage of body weight in PBB-fed pigs.
• Dermatosis was observed in two pigs on the 200 ppm PBB diet; however, no overt signs of significant liver, heart, or muscle necrosis were detected.

Conclusions:

• Dietary PBBs significantly impair growth performance and alter organ weights in pigs.
• While some hematological changes and organ weight increases occur, significant tissue necrosis is not evident at the tested levels.
• Pigs can recover normal growth and reproductive function after withdrawal of PBBs from their diet, suggesting a degree of reversibility.