The Tropentag 2011 Thematic Presentations on Animal Production Systems discuss various trade-offs between different animal feeds and feeding practices. The livestock in question ranged from cattle to shrimp and even guinea pigs! Presentations on Animal Production Systems at Tropentag 2011. Transforming to Integrated Ecosystems The common thread through all the presentations was how to integrate livestock production into the natural environment. Sustainable aquaculture that aims at minimizing impact on the environment can in the long run provide farmers with much better livelihoods. We were presented with some great use of Google map imaging depicting the boundaries of land usage and how livestock production can be integrated without degrading the environments around it. A ratio between environmental land coverage and live stock land usage enforces the ongoing theme of 'doing more with less'. Can we reduce our land usage yet increase agricultural productivity and at the same time reduce environmental impacts? The researchers at Tropentag present us with many small solutions such as mixed cropping, specific animal feed, or as far as alternative sources of energy. Life Cycle Assessments show that even fish livestock do have environmental footprints. It is important to consider that these livestock effect especially household livestock production as they can have a significant effect on their livelihood. Feed vs. Food Another thread of discussion throughout the thematic session debated whether farmers should be investing in feed for animals or instead investing it in food for themselves. For example in Uzbekistan, household farms heavily rely on a feed supply from outside instead of growing their own feed. The trade-off is where farmers can make the largest gain to support their livelihoods. Should farmers invest in food for themselves, feed for livestock, or plants such as banana trees that provide some feed and some food? Tropentag researchers have been testing the effects of using different feeds, using different chemical compositions or organic compositions, to see which has the most positive effect on livestock. There is a general consensus that optimizing a feed regime can significantly improve animal production efficiency. Self sufficient and sustainable livestock practices such as growing crops that provide both feed and food also prove to be very beneficial. Guinea Pigs! The highlight of the session came with the final presentation on the Impact of Guinea Pig Husbandry in Tanzania by Theda Matthiesen. Matthiesen’s topic not only brought a hearty chuckle to the crowd, but it also captured the interest of all listeners in the room. By the end of the presentation, and after a series of little guinea pig pictures, the crowd seemed strongly convinced of the advantages of guinea pig husbandry. Due to low maintenance requirements, fast breeding, very low resource input requirements, high resilience to diseases, guinea pigs can easily be maintained as livestock. Their uses range from the manure to the meat, which is becoming the second most popular meat, next to beef, in guinea pig households in Tanzania. It is often consumed as a snack or as an offering to honorable guests. Theda Matthiesen at Tropentag 2011. There is a significant number of small animals in livestock households in Tanzania, and guinea pigs can be found in almost 57% of households. It goes to show that the common European pet can also be a very relevant livestock for the poorer people in Tanzania, and there is potential for guinea pig husbandry on a supra-regional level!