have a spot lined up that has a good background around 10 in the morning. use a flash, yes, even in the daylight on black cattle. probably the person moving the cattle is more important than taking pictures. they need to be good at setting them up. it looks like you are kneeling down good. get pickier on feet placement. get the nearside rear leg a little more back, and in my opinion, it's ok if it's beyond vertical towards the rear. there are little tricks to make them longer fronted, look thicker etc depending on little moves of perspective. sometimes, if your camera can do it, do quick shots and move the camera around in a 1 foot circle till you know where you need to be. you notice how the shadow of the ears is going down? that's what having the sun low in the sky eliminates. it also lightens up the darker spots that are hidden when the sun is up high.
by the way, the first picture lighting looks better in my opinion. also, the light patch on the shoulder is distracting. otherwise nice calf!