Case history
This is a 180 cow herd calving all the year round. The Correct Magnets were installed on the drinking water supply during the last week in July 1999. Roughage ration is a mixture of grass and maize silage balanced by a blend for maintenance plus, concentrates being fed to the high yielders in the parlour. First cut grass silage was cut more mature in 1999, which resulted in poorer quality silage at 0.5 ME lower.
This herd has a history of mediocre fertility, being on land with low copper levels, with % conception to 1st service being in the mid 50's. Rations are supplemented by a high copper mineral, however in August 1999 this mineral supplement was reduced by 50%. The object of this assessment was to establish whether an improvement in fertility and milk production was achieved in the six months after the Correct Magnets were installed.
The following figures are taken from NMR and the fertility was assessed on the 3 months rolling mean of % conception to 1st Service. Milk production benefits have been assessed by comparison of performance in 1998 and 1999 in three different ways:-
The Correct Magnets were installed in the last week of July 1999.
Results
Fertility Improvement
This was assessed by monitoring the 3 month rolling average of Conception to 1st Service.
| 25.8.99 | 58% | July served cows |
| 28.9.99 | 56% | August served cows |
| 27.10.99 | 57% | September served cows |
| 25.11.99 | 58% | October served cows |
| 23.12.99 | 60% | November served cows |
| 27.01.00 | 69% | December served cows |
The farmer calculates that he has saved ½ straw per 80 cows served from August 1999 to beginning of February 2000. Savings: 40 straws @ £14 = £560
In August 1999 mineral supplementation was reduced by 50%, the projected annual saving is £1,462. This decision was not prompted by the magnet installation. However, there has been no detriment to fertility.
Savings of over £2000 this year for an outlay of £230.
Milk Production
| 1999 | 1998 | Increase/decrease in 1999 | ||
| Apr-Jul | 36.13 | 36.53 | -0.40 Litres | Magnets installed Jul 99 |
| Aug-Dec | 27.22 | 24.36 | +2.86 Litres |
| 1999 | 1998 | Increase/decrease in 1999 | ||
| Aug-Jan | 34.95 | 31.22 | +3.73 Litres | |
| October | 37.60 | 32.10 | +5.50 Litres | 3rd month of Lactation (Peak) |
| 1999 | 1998 | Increase/decrease in 1999 | ||
| Aug-Jan | 27.63 | 25.75 | +1.90 Litres | Magnets installed Jul 99 |
| B/F% | 3.92 | 4.18 | ||
| Pr% | 3.38 | 3.34 |
Summary
Fertility
Despite mineral supplementation being reduced in August 1999 by 50%, the 3 month rolling mean of conception to 1st service has risen from 58% for July served cows to 69% for December served cows.
Milk Production
The comparison of lactation performance of April calved cows highlights the benefits of Magnetically Conditioned Drinking Water in mid lactation.
The group of 1999 cows yielded 0.4 litres less per cow per day during the first four months of lactation, but after the magnets were installed they produced an impressive extra 2.8 litres per cow per day than the cows in 1998 throughout the last five months of lactation.
The August calved cows in 1999 yielded an extra 3.8 litres per cow per day over six months peaking at an extra 5.6 litres in the 3rd month of lactation. The whole herd yielded an extra 1.9 litres per cow per day for six months after installation of the magnets. We do appreciate that genetic improvement will have accounted for some of this increase, however, in our opinion taking all three different assessments into consideration they confirm the benefits of the Correct Magnets.
The butterfat and protein figures show a similar trend as found in previous assessments with the average butterfat % being marginally down and protein % being marginally up.