Sixty-five primiparous cows were used in two experiments to study the effects of feeding high or low levels of concentrate during the last 2 to 3 weeks before calving on performance in early lactation. During early lactation (until 12 or 16 weeks after calving) all the 23 cows in experiment 1 were given the same diet. In experiment 2, the 42 cows were given diets with a ratio of concentrate/forage of either 60:40 or 40: 60, each providing the same energy level.

The food intake of almost all the cows decreased in the few days before calving but the decrease was less pronounced among those on the low concentrate level before calving. The average daily food intake during the calving week gave a metabolizable energy intake about 30 MJ higher on the high compared with the low feeding level. The level of feeding before calving had no effect on the cows' food intake after calving, or on their milk yield, health and fertility, or on scores for udder oedema and sole haemorrhages. The high level offeeding before calving was associated with significantly higher concentrations of insulin and lower concentrations of free fatty acids in the calving week of lactation but the level offeeding either before or after calving had no effect on these concentrations in the 8th week of lactation. The feeding of a high ratio of concentrate/forage after calving was associated with a significantly lower milk fat content. It can be concluded that the concentrate/forage ratio at calving does not seem to have any significance for the performance after calving.

Two groups of 16 cubicle-housed Holstein-Friesian cattle from weeks 3 to 27 of lactation were offered either a proprietary protein supplement of animal origin (P) or soya-bean meal (S) as the protein source in the concentrate in a continuous design experiment. Concentrates were offered mixed with grass silage as complete diets to give a forage: concentrate ratio of 41: 59 and a crude protein content of 213 and 210 g/kg dry matter (DM) and a metabolizable energy content (MJ/kg DM) of 11·9 and 12·0 for P and S respectively. There was no significant difference due to diet for mean locomotion score (1·75 v. 1·66 (s.e. 0·15)), prevalence (0·1 v. 0·09 per cow per week) or incidence of lameness (0·04 v. 0·04) for P and S respectively. Similarly there was no effect on hoof growth, wear, hardness or conformation. Sole haemorrhages, indicative of subclinical laminitis, were observed throughout the experiment but were most severe at approximately 16 weeks after calving. Levels of heel erosion remained constant throughout. There was no significant effect of treatment on either heel or sole lesion formation. No significant differences were observed between treatments for milk yield, live weight, condition score or blood metabolites. The conclusions from this study were that source of dietary protein has no effect on dairy cow lameness or the development of sole lesions indicative of subclinical laminitis.

Three groups of 16 cattle each comprising three multiparous Jersey cross Holstein-Friesian cows, seven primiparous and six multiparous Holstein-Friesian cattle were offered, ad libitum, a silage-based complete diet with different concentrate ingredients following an initial 3-week covariate period. The relationship between these three diets and other parameters with lesions of the weight-bearing surface of the hoof was studied by scoring mobility weekly (locomotion score) and examining all the feet of all cows for visual lesions particularly those involving the horn of the foot. In addition hoof angle, hardness and growth and wear were also recorded. The mean locomotion score during the initial 3-week covariate period was a significant covariate for the subsequent locomotion score, milk yield, and live weight (P < 0·001). Furthermore weekly locomotion score also proved a significant covariate for weekly milk yield (P < 0·05). There were no significant differences between dietary treatment groups for locomotion score, overall lesion score (despite significantly fewer ulcers of the sole in one dietary group: P < 0·001) but a significant (P < 0·05) difference between cow ‘type’ and there was also a significant (P < 0·05) diet × breed interaction for locomotion score and milk yield. It was concluded first that initial mobility was an important factor in subsequent mobility of the cow and so experimental design; secondly that while nutrition and genotype interacted to influence mobility, visual lesions of the hoof and lameness, the mechanisms involved were far from clear; and thirdly that the simple lesion score used required some adjustment or correction factor(s) to ensure that more severe lesions were given a greater weight than a simple unitary increase.