能源、气候与材料2017journals.plos.org
狗和猫食物消费的环境影响
Environmental impacts of food consumption by dogs and cats
入门 · 约 45 分钟读完前置知识：基本环境科学概念、畜牧业供应链常识
导读
这篇 PLOS ONE 论文估算美国猫狗的食物消费对环境的影响，指出宠物食品（尤其是肉类成分）的消耗量约占人类食物消耗的 30%，其土地、水和温室气体足迹可观。论文还讨论了高端宠物食品趋势加剧了与人类食品系统对动物产品原料的竞争。
HN 关注点：HN 读者争论的核心是：宠物食品是否真的与人类争夺肉类资源，还是只是利用了人类不吃的副产品，以及养宠物与养孩子在碳足迹上的比较。
HN 评论精选
这几条评论里：质疑 2 补充 1 亲历 1
亲历亲历者指出宠物食品用的是真正无人要的废弃物，而非人类可食用的部位
我在肉类加工厂工作过，可以保证没人会想吃进入宠物食品“炼制”环节的那些东西。我不是说内脏、肚、下水这些有人类消费市场（有些还是高毛利产品）的部位——动物几乎每个部位在世界上都有市场。进入宠物食品的只是被污染的或没有更高价值用途的部分。基本上宠物吃的是废弃物。冷知识：牛肉加工厂利润最高的产品是胎牛血，通常约 400 美元/升，有时能涨到 1000 美元/升。
jgbond查看英文原文
Having worked in a meat processing plant, I can assure you that no humans would want to eat anything that goes into "rendering" for use in pet food. I'm not talking about offal, tripe, small goods, etc., all of which have markets for human consumption. Some of those items are high margin, too. There are markets somewhere in the world for just about every last bit of an animal. The only stuff that goes into pet food is stuff that has been contaminated or that has no higher margin use in other applications. Basically, pets get the waste. Fun fact -- The highest margin product in a beef house is fetal calf blood. It typically goes for about $400/liter and can sometimes spike up to $1000/liter.
质疑批评论文标题党且论证粗糙，暗示宠物主人应感到内疚
标题很标题党。文章虽然引用了“喂给宠物的肉大部分不适合人类食用”这一概念，却没有考虑实际相关影响，只是含糊地说对不适合的部分进行后加工。最糟糕的是这段：宠物食品可能已经可以食用，是“最后的蛋白质来源”，有报道称贫困美国人靠吃宠物食品补充饮食……总之：你的猫狗可能太胖了，你应该为此感到内疚。
jaclaz查看英文原文
Clickbaity title. Original: Environmental impacts of food consumption by dogs and cats Anyway,it's not like the article seems like being a particularly good one, while it cites the concept that meat fed to pets is (largely) not suitable for human consumption, doesn't take into account the actual related impact and vaguely talks of post-processing the non-suitable parts. The IMHO terrible part is this one: >And much pet food probably is already edible and serves as a potential source of protein as a food of last resort; there are reports, both official and unofficial, of impoverished Americans eating pet food as a necessary supplement to their diet [55–57, 58, 59]. At any rate, the trend toward premium pet food with more animal products that Americans would recognize as edible indicates that pets are eating animal products that could also be eaten by humans and that there is direct competition with the human food system for ingredients in some of these products [10]. TL;DR: Your cat and/or dog is probably too fat, and you should somehow feel bad about it.
质疑质疑宠物食品是否真的增加了畜牧业的总体规模
我猜宠物吃的主要是人类不想吃的动物部位，所以这不一定意味着宠物扩大了畜牧业规模。
centimeter查看英文原文
I assume pets are mostly getting the parts of the animal that humans don't want to eat, so this doesn't necessarily imply that pets increase the scale of animal agriculture.
补充指出西方人只吃精肉的习惯才是内脏流向宠物食品的原因
如果人们重新学会爱吃内脏，这个比例可能会很不一样。很多西方人只吃肌肉组织，还偏好瘦肉。可惜了他们……更多的舌头、肝脏和牛肚留给我！
ravenstine查看英文原文
If people learned to love organ meats again, the proportion would probably be very different. So many people, especially in the west, will only eat muscle tissue, and even then they prefer it to be very lean. Too bad for them... more tongue, liver, and tripe for me!
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从这篇论文所有 HN 讨论帖的全部评论里整理出来的链接。
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- 2017Hacker News 讨论帖165 分 · 89 评
- 2021Hacker News 讨论帖86 分 · 156 评
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