milk samples from high and low milk producer holstein cows, were obtained during the morning and afternoon milking over a one week period. overall, 1064 samples were tested within 14 times sampling in urmia, iran. milk macro-mineral concentrations in the morning milking and in low producers were greater than in the afternoon and in high producers. the highest and lowest concentrations were obse...

The dry period between successive lactations is crucial for regeneration of productive function of mammary tissue, preparation for high production, and to prevent new intramammary infections (IMI). With continually increasing production levels over time, the stress of abrupt drying-off could be a welfare concern, as well as an increased risk period for new IMI. The objectives of this study were...

The objective of this study was to identify factors associated with bulk milk coliform count (CC). Dairy farms (n=10) were visited once weekly on sequential weekdays over a period of 10 wk. During each visit, in-line drip samplers were used to collect 1 milk sample from 2 points of the milk line (between the receiver jar and milk filters, and after the plate cooler). During the same period that...

Once-a-day (OAD) milking offers a major opportunity to improve labour output on New Zealand farms. However few full lactation studies have been undertaken to investigate the effect of this strategy on the productivity of the farm system. A trial was established in 2000 to measure the effect of milking frequency and breed in farm systems where stocking rate was adjusted to equalise per hectare f...

Automatic milking systems (AMS) offer relief from the demanding routine of milking. Although many AMS are in use in Europe and a few are used in the United States, the potential benefit for American farms is uncertain. A farm-simulation model was used to determine the long-term, whole-farm effect of implementing AMS on farm sizes of 30 to 270 cows. Highest farm net return to management and unpa...

In dairy cattle, many farming practices have been associated with occurrence of mastitis but it is often difficult to disentangle the causal threads. Structural equation models may reduce the complexity of such situations. Here, we applied the method to examine the links between mastitis (subclinical and clinical) and risk factors such as herd demographics, housing conditions, feeding procedure...