cow sacrifice not for killing

 
Aśvamedha yajnas or gomedha yajnas, sacrifices in which a horse or a bull is sacrificed, were not, of course, for the purpose of killing the animals.
Asvamedha yajnas or gomedha yajnas, or the sacrifices in which a horse or a bull is sacrificed, were not, of course, for the purpose of killing the animals. Lord Caitanya said that such animals sacrificed on the altar of yajna were rejuvenated and a new life was given to them. It was just to prove the efficacy of the hymns of the Vedas. By recitation of the hymns of the Vedas in the proper way, certainly the performer gets relief from the reactions of sins, but in case of such sacrifices not properly done under expert management, surely one has to become responsible for animal sacrifice. In this age of quarrel and hypocrisy there is no possibility of performing the yajnas perfectly for want of expert brahmanas who are able to conduct such yajnas. Maharaja Yudhisthira, therefore, gives a hint to performing sacrifices in the age of Kali. In the Kali-yuga the only sacrifice recommended is the performance of Harinama yajna inaugurated by Lord Sri Caitanya Mahaprabhu. But one should not indulge in animal killing and counteract it by performing the Harinama yajna. Those who are devotees of the Lord never kill an animal for self-interest, and (as the Lord ordered Arjuna) they do not refrain from performing the duty of a ksatriya. The whole purpose is, therefore, served when everything is done for the will of the Lord. This is possible only for the devotees.    (More...)
The killing and rejuvenation of such old and invalid cows was not truly killing but an act of great benefit
"In this age of Kali, five acts are forbidden: the offering of a horse in sacrifice, the offering of a cow in sacrifice, the acceptance of the order of sannyasa, the offering of oblations of flesh to the forefathers, and a man's begetting children in his brother's wife." The word pala-paitrkam refers to an offering of flesh in oblations to forefathers. Formerly, such an offering was allowed, but in this age it is forbidden. In this age, Kali-yuga, everyone is expert in hunting animals, but most of the people are sūdras, not ksatriyas. According to Vedic injunctions, however, only ksatriyas are allowed to hunt, whereas sūdras are allowed to eat flesh after offering goats or other insignificant animals before the deity of goddess Kali or similar demigods. On the whole, meat-eating is not completely forbidden; a particular class of men is allowed to eat meat according to various circumstances and injunctions. As far as eating beef is concerned, however, it is strictly prohibited to everyone. Thus in Bhagavad-gita Krsna personally speaks of go-raksyam, cow protection. Meat-eaters, according to their different positions and the directions of the sastra, are allowed to eat flesh, but never the flesh of cows. Cows must be given all protection.    (More...)
"Therefore the great sages sometimes killed old animals, and by chanting Vedic hymns they again brought them to life for perfection.    (More...)
"The killing and rejuvenation of such old and invalid animals was not truly killing but an act of great benefit.    (More...)
"Formerly there were powerful brahmanas who could make such experiments using Vedic hymns, but now, because of Kali-yuga, brahmanas are not so powerful. Therefore the killing of cows and bulls for rejuvenation is forbidden.    (More...)

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