A major benefit of sunflower meal is that it does not have antinutritional factors such as those found in soybean, cottonseed and rapeseed meals. For that reason, it is considered to be a safe feed for all species, its only limitations being its fibre content and amino acid deficiencies. However, residues and contaminations from sunflower cultivation, harvest and post-harvest operations may be of concern.
Copper toxicity
The use of fertilizers containing copper occasionally result in high copper levels in sunflower products. Sheep are more susceptible to chronic copper poisoning than other livestock. In south-eastern Spain, deaths have been reported in lambs that had consumed sunflower meal with moderate Cu content (up to 14 mg/kg), but with high copper:molybdenum ratio (over 6:10), making toxicosis very likely. Sunflower products should be fed to sheep in combination with sources of molybdenum, such as green forage, that may help to prevent excessive accumulation of Cu in the liver (Garcia-Fernandez et al., 1999).
Contaminations during processing
Sunflower meal may be contaminated during harvest and post-harvest operations: risk factors are pesticides residues, hexane residues, dioxin contamination resulting from the utilization of anticaking agents, mycotoxin development due to poor drying before storage and salmonella (FEDIOL, 2010).
Eggshell staining
Chlorogenic acid, a phenolic compound present in sunflower meal, causes eggshell staining when eggs come in contact with sunflower meal dust. Feeding poultry with sunflower meal pellets and frequent egg collection alleviate this problem (Daghir, 2008).