BLOAT IS GREATEST DETERRENT TO DAIRY PASTURE IMPROVEMENT BUT FIBRE FEEDING ASSISTS IN CONTROL

Bay of Plenty Beacon, Volume 15, Issue 44, 15 May 1950, Page 5

BLOAT IS GREATEST DETERRENT TO DAIRY PASTURE IMPROVEMENT BUT FIBRE FEEDING ASSISTS IN CONTROL

(By „E. R. Marryatt, Field Instructor, Department of Agriculture, Whakatane).

Probably the greatest deterrent to pasture improvement on dairy farms in New Zealand is bloat. When farmers lose several cows ' by bloat in a week and the loss is greater than the month’s cream 'Cheque then it is small wonder that many are reluctant to go in for more clover and for better strains of . clover. With considerable justification they say that is not worth the trouble. This article discusses the important problem of how to have good clovery r pastures and yet, at the same time, little bloat. T

For high production of leafage, pastures must contain clovers. All clovers are helpful, but some are better than others. White clover is better than all the rest and Government Certified New Zealand white clover is the best strain. To carry* out their function of fixing nitrogen for their own use and for the use of the grasses which are growing with them, clovers must be given enough of the food they require and they must also be allowed to) grow vigorously. These facts are now widely recognised by the New Zealand dairy farmer and pasture improvement is along these lines and is fairly general.

Likely From Clover But many dairy farmers find that as soon as they get clovery pastures they also get a great deal of trouble and often considerable loss from bloat. It is quite true that colvers do cause bloat and that the better the clover the more likely is bloat But it is also true that cows can and do die quickly from bloat on grass alone though this is much less likely and much less common than on clover. Most bloat is caused not so much because of the clover itself as by the succulence and leafiness and \ immaturity and what goes with these features of rapidly-growing pasturage. Tender, young, protein-rich, fibre-deficient, rapidly-growing leaves of grass will cause bloat in the same way as will the same kind of leaves of clover. Not so much bloat occurs on grassy, clover-deficient swards because through insufficient clover, the grass simply cannot grow abundantly. ' Why is .this tender young leafage -which is so good for milk produc“tion so likely to cause bloat? Because the milking cow has a digestive system specially adapted With large amounts of fibrous fodder and because she is used to dealing with fibre she naturally requires a certain amount of it. When there is not enough fibre in the food she eats her digestive process is upset and because of more than usually rapid fermentation and formation of gasses which are unable to escape, the cow bloats. Normally, the cow spends part of her time in collecting food and then Ties down at leisure with what she has collected an she spends a good deal of that time in chewing the cud. Fibre is necessary to form a cud. Where there is a great deal of fibre in the food as in hay, the intake of that food is necessarily slow and is limited in quantity because the more fibrous the food, the more time is required to eat and to ruminate. • When rapidly-growing, succulent and fibre-deficient food like spring pasturage is all that is available then the dairy cow is inclined to eat far too quickly and :.£ar too much and both these faults in feeding upset most stomachs.

To Distress Fj To add to the cow’s distress undpr circumstances fermentation and gas formation is very rapid indeed with this type of fodder and because of insufficient fibre to allow pockets of these gases to collect and escape, a frothy mass of fermenting material often results; the frothiness rapidly increases; the grasses do not collect into large enough quantities in one place to allow them to be belched forth; the cow’s stomach becomes terrifically distended; the diaphram is pressed hard against the heart and lungs; breathing becomes impossible „and the cow quickly dies. This is by no means a complete explanation of bloat but is satisfactory from the point of view of this article for if only the bloat which is caused in this way can be prevented or even reduced then a great deal of progress will have been made. The aim is to promote freedom from fear of mor-e bloat from more and better clover and to show how better management will result in reduced losses from bloat and increased production from better pastures. f If as has been shown earlier, the fibre content of the fodder determines how quickly and how much the cow will eat, and we offer her a free choice between unlimited succulent, high-protein, low-fibre grass and clover or some- hay to go with it, will she eat the hay first or along with the grass and clover and avoid trouble? No, generally

she will not. More likely she will set amout eating about two-thirds of the food she requires from the high-quality grass and clover before topping-off on hay. The trouble often is, however, that before she has reached the hay-eating stage she has become bloated.

Insist On Hay First The wise dairy farmer therefore gives her no option but insists that she eat the hay first. As she will not obey orders to eat the hay first he simply does not allow her into a dangerous pasture until she has eaten some hay. She will have no choice but to eat hay first if hay is put out in a rack in the holding yard. If -she refuses to eat it then it is probably not good hay. Bad hay cannot be made into good hay but it can be made a little more attractive by the use of molasses. But whether the hay be good or bad it is very important that it be eaten before dangerous pasturage.

Fibre may not be very good for milk-production but it is very safe and dead cows produce no milk at all.