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You read about some concerns that have been raised about farming tuna. However, researchers are finding promising solutions to these problems. First, it's true that tuna farms need to be stocked with wild young. But this may soon no longer be the case, thanks to a breakthrough. Scientists found that they can get captive females to lay their eggs by injecting them with certain hormones. These injected hormones get the females to lay eggs reliably without posing health risks to the tuna or to consumers later on. With this advancement to the farming can be done without further reducing wild populations. Second, yes, tuna must eat a high protein diet and they usually get protein from fish, but the protein had tuna need doesn't have to come from fish. It can also be gotten from plants. Certain plants that are high in protein can be processed to make an inexpensive food for tuna. This food made from plants, could supply captive tuna with all the protein and nutrients they need. And since the plant derived food is inexpensive, the cost of tuna from tuna farms can be kept low. Third, parasites attack many ocean fish farms, but steps can be taken to treat infestations. For example, scientists studying a parasite problem in tuna farms in southern Australia discovered how to greatly reduce blood fluke infestations there. They found that when tuna cages were moved farther offshore into deeper waters, far fewer tuna had blood flukes in their bodies. It turns out that blood flukes need to stay close to shore to do well. That's because certain resources that blood flukes require for their life cycle are not available farther offshore. Because the tuna cages were moved into deeper waters where the blood flukes cannot thrive, blood fluke infestations among the caged tuna were basically stopped.
Summarize the points made in the lecture, being sure to explain how they challenge the specific points made in the reading passage.
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