Tzaar Baalei Chayim

In Chutz La’aretz, this week parshas Balak is read, and in Eretz Yisroel, this is one of the rare years when we read parshas Pinchas before the Three Weeks. Since both parshiyos include allusions to tzaar baalei chayim, I present:

Tzaar Baalei Chayim

Question #1: Scientific experimenting

“Are there halachic laws governing when and how one may conduct scientific or medical experiments on animals?”

Question #2: Licensed to kill!

“Are there any halachic concerns that I should know about becoming an exterminator?”

Question #3: Oversized rider

pony“On visiting day in camp, we went pony riding, accompanied by some parents. One of our campers’ fathers is very obese, and the ponies were small, meant to carry the weight of children or, at most, average-sized adults. Fortunately for the pony involved, Mr. Big decided to forgo the ride. But does halachah address whether he would have been permitted to ride one of the ponies?”


The topic of tzaar baalei chayim, the responsibility to alleviate, avoid and prevent the suffering of animals, is discussed fairly extensively by the halachic authorities. One early source, the Sefer Chassidim, discusses this mitzvah in regard to this week’s parshah — within the context of Bilaam striking his donkey.

All authorities agree that it is forbidden to cause animals to suffer unnecessarily, such as to strike an animal out of anger or frustration (Sefer Chassidim #666). If an animal that is normally well-behaved and responsive to its vocation refuses to work one day, one should not beat it to get it to cooperate – rather, one should consider the possibility that it might be ill (Sefer Chassidim #668). Animals do get sick and, as we see from the story of Bilaam, they may have difficulty expressing themselves. Thus, the Sefer Chassidim teaches that Bilaam was punished for striking his donkey (Sefer Chassidim #668). This esteemed early authority thereby implies that a gentile is required to observe the laws of tzaar baalei chayim, an aspect of the mitzvah that we will leave for a future article.

One should not work his pregnant animal too hard when he knows that it is ready to give birth (Sefer Chassidim #667). It goes without saying that it is prohibited to raise livestock in an inhumane way, such as by feeding them an unusual diet or depriving them of proper ventilation or exercise. Also, tzaar baalei chayim includes alleviating the suffering of an animal (Orach Meisharim Chapter 15:1).

Using animals

One may use an animal to service people, even though doing so involves inflicting pain on the animal (Nimukei Yosef, Bava Metzia 32b; Terumas Hadeshen 2:105; Rema, Even Ha’ezer 5:14; these authorities base their rulings on Talmudic sources, see Chagigah 14b; Shabbos 110b and 154b; Avodah Zarah 13b). The rationale provided is that animals and the rest of creation were created in order to service mankind (Terumas Hadeshen, based on Kiddushin 82a).

How much suffering?

A question raised by earlier authorities: Is there a limit to how much pain one may cause an animal, if the goal is for human benefit? We find a dispute among rishonim whether it is prohibited to burden an animal excessively, so that humans can benefit. For example, may I place a load on an animal that is greater than it should be carrying? According to the Sefer Chassidim #666, this constitutes tzaar baalei chayim. On the other hand, the Terumas Hadeshen (1:105) rules that this is permitted. He further discusses whether one may remove the down, which is the soft feathers, from live geese. Is this halachically the same as shearing sheep, which is certainly permitted, or is it prohibited because of the level of discomfort? The Terumas Hadeshen concludes that although any use of an animal is permitted and does not violate tzaar baalei chayim, the custom is not to remove the down from live birds because this is very painful. This conclusion is quoted by the Rema as standard halachah (Even Ha’ezer 5:14).

Scientific experimentation

Is it permitted to use animals to run tests for medical research or other scientific experimentation? The earliest discussion I found on this question dates back over three hundred years, in a responsum penned by Rav Yaakov Reisher (Shu”t Shevus Yaakov 3:71), who permitted it. A much lengthier and very thorough analysis of the topic is found in a more recent work, the twentieth-century responsum of the late rav of Zurich, Rav Yaakov Breisch (Shu”t Chelkas Yaakov, Choshen Mishpat #34). He concludes that one may use animals to test products to see if they are safe, although it seems that this is permitted only when there is a direct research benefit and the potential suffering of the animals cannot be avoided. In other words, it is permitted to test a new medicine or cosmetic item on an animal to see if medical problems develop, but one may only do this to the extent necessary to see if the product is safe. One may not, while experimenting, abuse the animals in any way that is not necessary for the test being performed.

What is the halachah if the medical testing will cause excessive pain to the animals? Is this still permitted? As mentioned above, all opinions forbid inflicting or causing any unnecessary pain to animals. Whether one may conduct medical test or research that will cause considerable pain to the animal might be the subject of a dispute between the Sefer Chassidim and the Terumas Hadeshen. The Terumas Hadeshen rules that this is permitted, as long as there is human benefit. The Sefer Chassidim states that even human benefit permits only a degree of normal discomfort to the animal, but not an excessive amount.

However, it is possible that the Sefer Chassidim agrees that one may test a medicine under these circumstances, since the importance of the potential benefit is great. It would seem that he would prohibit testing a new cosmetic item that will cause an animal to suffer tremendously, whereas the Terumas Hadeshen would permit it.

The Shevus Yaakov concludes that testing a medicine or cosmetic item on a living creature to see if it is safe for humans is permitted, even if it causes much suffering to the animal (Shu”t Shevus Yaakov 3:71). This is because one is not causing pain to the animal directly, and one is trying to research whether this product is safe for people.


Some authorities bring evidence from the story of Shimshon that, when necessary, one may even cause excruciating pain to an animal. The book of Shoftim tells us that Shimshon captured 300 foxes and tied together their tails in a way that each knot held a torch; he then sent the foxes into the fields and orchards of the Pelishtim, burning everything to the ground (Shoftim 15:4-5). Thus, we see that one can cause tremendous pain to animals when necessary for human need.

However, others question this proof, since during warfare, much is permitted that is not otherwise allowed. Thus, in general, causing this degree of pain to an animal would certainly be forbidden (Shu”t Chelkas Yaakov).

Furthermore, I question this proof, since nowhere does it say that the foxes themselves were on fire – the torches that they transported set fire to the fields and orchards of the Pelishtim.

Animals or even insects?

Does the prohibition of tzaar baalei chayim apply to all living creatures? We find a dispute among the acharonim concerning this issue.

Rav Moshe Feinstein (Shu”t Igros Moshe, Choshen Mishpat 2:47) discusses whether one is permitted to work as an exterminator of unwanted mice, insects and other such wildlife. He rules that this is permitted when it is necessary for people, but that one should try to avoid killing the unwanted creatures directly.

Rav Moshe’s reason is that although it is permitted to eliminate pests when they are harmful to mankind, killing them still remains an act of cruelty that makes an impression on the neshamah of the person who does it. Rav Moshe demonstrates this from the fact that after we fulfill the mitzvah of destroying the ir hanidachas, the city that goes wayward, the Torah promises that Hashem will provide rachamim to the Jewish people (Devorim 13:18). Rav Moshe quotes the Ohr Hachayim, who says that notwithstanding that this destruction is necessary and fulfills a mitzvah, it still affects the neshamah of those involved, because doing brutal things makes one into a nasty person. However, the Torah promises that Hashem will provide us with rachamim, meaning that He will restore us to being our usual, merciful selves. In other words, He will remove from our neshamos the harm created by what we were forced to do. (To the best of my knowledge, this is one of only three places in all of Rav Moshe’s responsa that he quotes the Ohr Hachayim.) Similarly, exterminating varmints, even though it is necessary and therefore permitted, will affect one’s neshamah. Therefore, it is better to do the exterminating in an indirect way, which makes less of an impression on the neshamah. According to Rav Moshe, we can conclude that killing a fly, moth or other insect that is not bothering anyone is prohibited.

(Rav Moshe contends that shechting for food will not cause a person to become cruel, since this act fulfills a mitzvah, notwithstanding that one is not required to perform it. Rav Moshe seems to hold that since the Torah sometimes requires shechitah, such as, when offering a korban, its performance could never cause someone to become cruel.)

Insects should not apply

However, we find that an earlier authority, Rav Yaakov Emden, who sometimes referred to himself by his acronym Ya’avetz* (Yaakov ben Tzvi), did not understand that the concept of tzaar baalei chayim extends this far. He rules that tzaar baalei chayim does not apply to insects, but only to creatures large enough that mankind can use them for work (She’eilas Ya’avetz 1:110). Although Rav Yaakov Emden quotes the Arizal as having commanded his students not to kill even lice, the Ya’avetz explains this to be a midas chassidus, beyond the strict requirements of the halachah. In his understanding, it could be that the Arizal prohibited this destruction because it causes harm to one’s neshamah, the same line of reasoning that Rav Moshe applied to discourage an exterminator from killing insects in a direct way.

Is it prohibited min hatorah?

The tanna’im dispute whether the law of tzaar baalei chayim is min hatorah or whether it is only of rabbinic origin (Bava Metzia 32b; Shabbos 154b). One of the differences that results from this dispute is as follows: Let us assume that in order to avoid causing an animal pain or distress, one would need to violate a rabbinic prohibition. May one supersede the rabbinic prohibition in order to avoid tzaar baalei chayim? The answer is that if tzaar baalei chayim, itself, is only a rabbinic prohibition, one cannot violate one rabbinic mitzvah for the sake of another. However, if tzaar baalei chayim is prohibited min hatorah, then preventing suffering to an animal overrides a rabbinic prohibition (Shu”t Maharam meiRottenberg 3:181).

The following discussion of the Gemara will demonstrate this to us:

Rabban Gamliel’s donkey was laden with barrels of honey, and he did not want to unburden it until Shabbos was over. The Gemara asks why Rabban Gamliel waited until Shabbos was over, since this was clearly causing unnecessary discomfort for the animal. The Gemara replies that the honey had hardened and was therefore no longer suitable as a food, which would make it muktzah on Shabbos. The Gemara then asks why didn’t Rabban Gamliel release the ropes binding the barrels to the donkey so that they could fall off the donkey on Shabbos, something he could do without moving the muktzah. The answer was that Rabban Gamliel did not want the barrels to break. The Gemara, still not satisfied, asks why didn’t he place pillows under the barrels, thus cushioning their fall so that they would not break? The Gemara answers that the pillows would get dirty this way and become useless for the rest of Shabbos, and doing this on Shabbos is prohibited because of a rabbinic proscription called bitul kli meiheichano, literally, nullifying a tool from its use. The Gemara then asks that the prohibition of tzaar baalei chayim should supersede the rabbinic prohibition of bitul kli meiheichano. To this the Gemara replies that Rabban Gamliel held that the law of tzaar baalei chayim is only rabbinic, and therefore it does not supersede a different rabbinic prohibition (Shabbos 154b).

The Gemara’s conclusion

Notwithstanding Rabban Gamliel’s position that tzaar baalei chayim is forbidden only as a rabbinic injunction, there are other tanna’im who rule that it is forbidden min hatorah. The following passage of Gemara implies that Rabban Gamliel’s position is rejected by the later authorities in the time of the Gemara:

Rav Yehudah said in the name of Rav: One may place cushions and pillows underneath an animal that fell into an irrigation ditch to enable it to get out by itself. However, it is preferred to bring food and water to the animal for the rest of Shabbos, if possible, and if this will satisfy the animal’s needs, rather than place cushions and pillows underneath the animal, which will violate bitul kli meiheichano (Shabbos 128b).

This Gemara implies that if we can avoid both transgressing the law of bitul kli meiheichano and avoiding tzaar baalei chayim, we strive to accomplish both, but if that option does not exist, then tzaar baalei chayim supersedes the rabbinic prohibition of bitul kli meiheichano. Since this passage reflects the conclusion of the amora’im, we see that we do not rule in accordance with Rabban Gamliel, but rather we rule that tzaar baalei chayim is min hatorah. This is the halachic conclusion reached by most, if not all, halachic authorities (Shu”t Maharam of Rottenberg 3:181; Mordechai, Shabbos #448; Nimukei Yosef, Bava Metzia 32b; Sefer Chassidim #666; Shiltei Hagiborim, Shabbos chapter 18, pg. 51a note 3, quoting Riaz; Kesef Mishneh, Hilchos Rotzeach 13:9; Rema, Choshen Mishpat 272:9; Sma 272:12, 15; Gra, Choshen Mishpat 272:11). This law is also codified in Shulchan Aruch (Orach Chayim 305:19).

The Shulchan Aruch, reflecting this conclusion, cites a different halachah that results from the fact that tzaar baalei chayim is prohibited min hatorah. Although there is a rabbinic injunction prohibiting mounting or dismounting from an animal on Shabbos or Yom Tov, if someone did mount an animal, he is required to get off. (If this were forbidden, he would be required to remain on horseback the rest of Shabbos or Yom Tov, which would certainly cause tzaar baalei chayim.) This is true, notwithstanding that the act of dismounting constitutes a rabbinic violation of Shabbos (Shulchan Aruch, Orach Chayim 305:18). This ruling is consistent with our previous analysis. Since we conclude that tzaar baalei chayim is prohibited min hatorah, it can, when necessary, supersede a rabbinic prohibition, such as that of dismounting from an animal on Shabbos.

Violent rooster

Here is a related question, culled from the more contemporary responsa literature. If one discovers on Shabbos that one rooster is attacking other chickens, may one remove it from the coop on Shabbos, notwithstanding that a live animal is muktzah on Shabbos (Shu”t Har Tzvi, Orach Chayim 1:205)?

This question was asked of the late Rav Tzvi Pesach Frank, then rav of Yerushalayim. In his analysis of the topic, he quotes the previously mentioned conclusions of the Shulchan Aruch, that someone who mounted an animal on Shabbos should dismount it, because of tzaar baalei chayim, and that one must remove a burden from an animal, even by moving muktzah if no other method will work, because of tzaar baalei chayim. Therefore, Rav Frank concludes that it is permitted to remove the treacherous rooster from the others. He writes that it is preferred to have a gentile worker remove it, but if there is no gentile available, a Jew may remove it, notwithstanding that a rooster is muktzah on Shabbos. In other words, tzaar baalei chayim supersedes the prohibition of muktzah, when there is no way to accommodate both laws.


Shlomoh Hamelech teaches (in Mishlei 12:10) Rachamei re’sha’im achzari, that the compassion of the evil is cruelty. What does this mean, particularly since the context of the pasuk implies that it is discussing the care one takes of his animals? The example chosen by the Sefer Chassidim (#669) is of an evil person who fed his animal well, but then expects it to perform beyond its capabilities – after all, he treated it so nicely. When the owner’s expectations are not realized, he beats the animal mercilessly. It turns out that his initial compassion caused him to be cruel.

The Tosefta (Bava Kama, end of Chapter 9) states that Rabbi Yehudah said in the name of Rabban Gamliel: “Know this sign well: as long as you act with mercy, Hashem will have mercy on you.” Sefer Chassidim #666 notes: If we are merciful to our animals, Hashem and others will be merciful to us.

*Note that several different scholars are referred to by this acronym.