The Milk Producer - January 2010 - (Page 34)

RUMINATIONS By Mario S. Mongeon Avoiding milk fever Ensuring transition cows get the right diet puts them on the path to absorbing more calcium and staying healthy nsuring your cows can mobilize calcium efficiently in the early stages of lactation will improve your herd’s overall health status, and your farm’s bottom line. Otherwise, a common metabolic disorder, best known as milk fever, even at the subclinical level, could keep your cows from reaching optimum milk production. The most critical period of the year for a dairy cow is the transition from late gestation to early lactation. In these five to six weeks, many changes trigger substantial hormonal changes. At the same time, the cow’s metabolism diverts nutrients toward milk production. To further complicate the early transition period, her feed intake is at its lowest around calving time, and will not reach its maximum until several weeks after she freshens. Causing milk fever, or hypocalcemia as it is known clinically, is the cow’s inability to meet calcium demand for colostrum and milk production. Even if you don’t see a clini- cal case of milk fever in your herd, you could still have issues that impact a cow’s overall health status, milk production and your bottom line. Lack of appetite, poor dry matter intake in early lactation or a flat lactation curve may indicate a subclinical case resulting in lost milk production. When the condition is severe, clinical milk fever can even be fatal. Surviving animals, as well as those with subclinical milk fever, have increased risk of retained placentas, displaced abomasums and mastitis. In all cases, affected cows will produce less milk. Numerous studies have confirmed that changing a cow’s diet before she calves reduces the risk for clinical and subclinical milk fever. This involves lowering what is known as the dietary cation-anion difference (DCAD). A calculation is required to determine the DCAD value of a diet. Formulas are used to calculate Ruminations is prepared by Ontario Ministry of Agriculture, Food and Rural Affairs livestock technology specialists to provide information you can use on your farm. How she handles the transition period defines lactation success. 34 | January 2010 | MilkPRODUCER

Table of Contents for the Digital Edition of The Milk Producer - January 2010

The Milk Producer - January 2010
Editor's Note
DFO Vice-Chair's Message
Contents
Dairy Update
Farm Finance
Processor Spotlight
DFC Promotion
Victory Over Johne’s
Applied Science
Research
Ruminations
Farm Energy
Markets
New 'N' Noted
Back Forty

The Milk Producer - January 2010