This is an apt demonstration of why I regard morality to be an objective measure. (As I state in the comments!)
It requires certain axioms to work. The first is that morale behavior maximizes morale value - that morality is moral, in short. The second is that moral value exists respective only to a moral agent (a rock cannot be immoral, for it possesses no agency, nor can it be possessed of moral concerns; this relativity also implies that my moral bearing is not impacted by the decisions of other moral agents). The third is that moral value exists respective only to moral behavior - that is, specific decisions. (That is, moral value doesn't enter into situations over which I have no control.) The fourth is that moral agents may only have moral value while they are possessed of moral agency - to whit, a dead moral agent has no more moral relevance than a rock.
Because a rock cannot be possessed of a moral sense, morality cannot be universal - Ayn Rand used the word "intrinsic" rather than "universal" to describe this quality of morality. I prefer universal; I find it more accurate, if less precise.
But morality may still be objective, and I think this case aptly demonstrates why. As a corollary of the first axiom and fourth axioms, a moral agent has a moral obligation to exist, provided the moral value of that agent, and its continued existence, is greater than zero. (Demonstrating that this is the case is outside the scope of this argument, so for here, I will let it lay that a moral agent who has decided otherwise is morally free to cease existing.)
I'm not setting out to create a moral framework by which to interact with other living things - suffice to say, the cost of continued existence for all living things is extracted from other living things. Ecology is a zero-sum game. Insofar as it has morality, that morality is evolutionary fitness, the sole value which ecology seeks to maximize. Fitness, however, is without agency; a creature is fit or not fit without respect to its own decisions. Ecology lacks agency.
There is therefore no morality in ecology; whatever moral costs lay in killing the cow, the cow was burdened with for its existence prior to its death, for its own existence ruled another creature's existence out, who in turn would have ruled another's out. There is neither intrinsic nor objective morality in ecology; the moral costs exist solely with respect to ourselves, in determination with the moral framework we each have created in dealing with other creatures.
But only where we have agency. If our ecological existence requires the flesh of a cow, then there is no morality, or more specifically immorality, in consuming it.
(My personal determination is that we do the cow an amoral service by consuming it; we maximize its fitness, for we raise it to those ends. Fitness I judge to be the cows sole domain of value, albeit an amoral value, for it was its sole domain of value before we interfered, and we have not sought to raise the cow to agency or awareness. Therefore the act of eating meat is an amoral act. Cruelty is another matter altogether.)