לזכות רפואת אבי מורי ר' יצחק יונה בן חנה ור' מרדכי דוד בן קריינא ודינה ברכה בת אסתר הדסה בתוך שח"י 

Is not eating before you feed your animals a mitzva or issur? 

Nafka Minahs: 

1] מצוות צריכות כוונה: If it is a mitzva it requires kavanna. If it is an issur, it does not. 

2] עוסק במצוה: If it is an aveira then even if one is busy with another mitzva he is not פטור from feeding his animals. If it is a mitzva then if he is doing another mitzva he doesn't have to do this one b/c עוסק במצוה פטור מן המצוה.

Or if someone is feeding his animals does he stop for another mitzva? If it is a mitzva then he wouldn't. If it is an aveira then maybe would. Or maybe we would say that this is לכת שמים and not לכת דידך [see Succah 25a] and he would be פטור from the other mitzva. 

3] Do we say עשה דוחה לא תעשה? If it is a mitzva then it overrides aveiros. If it is an aveira then it would not override mitzvos but rather would be overriden by mitzvos.

4] At what expense: Mitzva - up until a fifth of one's money. Aveirah: Everything if necessary. [The Chofetz Chaim writes that even for an איסור דרבנן you have to pay all of your money].

5] If there is an instance of פיקוח נפש and one would have to be מבטל this din. We have a rule of הקל הקל תחילה - first we transgress the lesser aveira. So that would mean that if it is a mitzva it is easier to transgress while a לא תעשה is more severe [יבמות ח, א].

6] If it is an aveira one would be allowed to override it in order to allow his friend to do a mitzva. If it is  a mitzva then the rule is you never have to forgo a mitzva to allow your friend to perform a more stringent mitzva. 

7] If he is not sure if he fed them. If it is a mitzva then he has to do it again just in case b/c he has a חזקת חיוב. If it is an aveirah then there is no חזקת חיוב. [And if it is מדרבנן as the Magen Avraham holds - he can go לקולא]. 

8] Is he allowed to bring himself into an אונס and become פטור? If it is a mitzva then yes [like wearing a 4 cornered garment w/o tzitzis on Shabbos which is permitted b/c he is אנוס that he may not tie tzitzis]. If it is an aveira then no. 

9] If it is a mitzva then you would have to give an עני money to do this mitzva as the ביאור הלכה paskens in hilchos chanuka while if it is an aveira then one is not obligated to give tzdaka to prevent an aveira באונס. 

10] If he cannot fully give his animal what the animal needs. If it is a mitzva then no b/c there is no חצי שיעור מצוה [according to the 'דובב מישרים ח"ב סי' י but that is hotly contested]. If it is an aveira then he should give them whatever he can. 

[מאוצרות הגר"א גנחובסקי זצ"ל]