Cows and bullocks are social animals and are most comfortable when they move and socialize with herd mates. As shown in this photo, a large number of farmers tie their animals with a short leash. In such a situation, animal can’t sit comfortably for rumination and it can’t rest lying down. A cow for good health and better milk production should ruminate for at least 6-8 hours and rest for around 12 hours. Every cow has a different comfort position to sit and rest which she can’t follow if the cow is tied for major part of the day. In order to give clean milk cow must sit and lie on clean floor free from soiling of the body. When a cow is tied, it is forced to defecate and urinate on the spot and then is forced to sit on this shit. This is a major cause of udder and uterine infections seen in cows that are tied on cement concrete floor.
Research has shown that when cows (especially Zebu) are tied the stress level as determined by cortisol level in blood is high. This results in increased aggressive behaviour. Interestingly, farmers think that cows and bulls should be tied because these are aggressive and might fight. On the contrary it is seen that cows that are left free day and night are more docile whereas the ones tied are more aggressive. When you keep cows free they can also express sexual behaviour expression overtly hence in such farms detection of heat is easy and fertility is high. Since cows managed untied sit and rest longer are able to ruminate more vigorously hence there is better digestion and lower consumption of feed. Such cows also improve in milk production and quality.
Tethering is permitted only if animal has to be given an area for grazing and for this recommended leash length is 9 meters. But tying animals even for two hours leads to high stress levels hence not advised.