The Vedas are traditionally divided into two parts: Karma kanda and Jnana kanda. The Karma kanda consists of Yajnas involving animal sacrifice. Ancient Sri Vaishnava commentators and acharyas say that the Yajnas in the Karma kanda are a form of worship to Vishnu.
This means that Vishnu is pleased by animal sacrifices.
What do Sri Vaishnava acharyas specifically say about Vishnu being pleased by animal sacrifices?
The following are Mantras from the Krishna Yajurveda's Book 2 and Book 5. The Mantras are describing which animals are fit to be sacrificed to what Vedic deities. They also give the list of animals which are to be offered to Vishnu.
The gods and Yama were at strife over this world; Yama appropriated (ayuvata) the power and strength of the gods; therefore Yama has his name . The gods reflected, 'Yama here has become what we are.' They had recourse to Prajapati. Prajapati from his body fashioned out the bull and the cow; the gods offered a cow to Visnu and to Varuna, a bull to Indra; they caused him to be seized by Varuna and by Visnu, the sacrifice, they drove him away; his power they appropriated by means of that for Indra. He who has foes should in strife offer to Visnu and Varuna a cow , to Indra a bull; verily causing his foe to be seized by Varuna, by Visnu, the sacrifice, he drives him away, he appropriates his power by means of that for Indra, he prospers, his foe is defeated.
(Book 2 part 1)
The red, the dark red, the jujube red, these are for Prajapati; the brown, the reddish-brown, the parrot brown, these are for Rudra. The white, the white-eyed, the white-necked, these have the fathers as their deities. Three black barren cows are for Varuna, three white barren cows for the Sun; the dusky-spotted hornless ones are for Mitra and Brhaspati. The dappled, the one with cross-lines dappled, the one with dappled marks running up, these are for the Maruts; the bright, the ruddy woolled, the white, are for Sarasvati; the piebald, the grey piebald, the slightly piebald, these are for the All-gods; three dark barren cows are for Pusan, three ruddy barren cows for Mitra; the red-spotted hornless ones are for Indra and Brhaspati. v. 6. 13. The white limbed, the one with white limbs on one side the one with white limbs on both sides, these are for Indra and Vayu; the one with white ear-holes, that with one white ear-hole, the one with both white ear-holes, they are for Mitra and Varuna; the one with a pure tail, the one with a completely pure tail, the one with a tail in lumps, these are for the Açvins; three barren cows of varied colours are for the All-gods, three white for the supreme lord; the white-spotted hornless ones are for Soma and Pusan.
The humped, the bull, the dwarf (animal), these are for Indra and Varuna; the one with white hump, the white-backed, the white-rumped, these are for Indra and Brhaspati; the white-footed, the white-lipped, the white-browed, these are for Indra and Visnu; the three white-flecked barren cows are for Viçvakarman; the three with piebald bellies are (to be offered) to Dhatr; the white-spotted hornless ones are for Indra and Pusan. Three long-eared ones are for Yama; three white-footed for Soma; three ichneumons [sic] are (to be offered) to Agni, the youngest; three ruddy eighteen-month-old (sheep), these are for the Vasus; three red gallinules [sic], these are for the Rudras; the brown-spotted hornless ones are for Soma and Indra.
Three small-eared are for Visnu; three with red-tipped ears are (to be offered) to Visnu, the wide strider; three with dewlaps are (to be offered) to Visnu, the wide goer; three of two and a half years old are for the Adityas; three of three years old are for the Angirases; the yellow spotted hornless ones are for Indra and Visnu
To Aditi are (to be offered) three ruddy-spotted; to Indrani three black-spotted; to Kuhu three red-spotted; three calves to Raka; three heifers to Sinivali; the red-spotted hornless ones are for Agni and Visnu
So, the point is when some rite has been prescribed in Veda itself for the satisfaction of the Vedic deities then why would that rite be objectionable to one such deity?
Also note that sacrificial killing is non-killing. All Hindu scriptures agree with that.
