| Since most pesticides are not biodegradable, once they enter the food chain they persist in plant or animal bodies. |
| Change is also in the air for the farming industry at the bottom of the food chain. |
| Both pathogens can colonise the intestines of beef cattle and get into the food chain during slaughter at the abattoir. |
| Experts speculate that the python could fight its way to the top of the food chain, ousting its native reptile adversary. |
| Mercury concentrates in large fish at the top of the food chain, but these fish are not used as the source of most fish oil. |
| Fluctuations in price spreads suggest relative variation in consumer demand and cattle supply entering the food chain. |
