cows in field

Recent Odairy Discussion, June 2010

Pasture rule questions: how many acres per cow for a year's forage needs; how apply 30 percent rule across grazing season? Treating milk feaver symptoms. Treating, or preventing, prolapse. Surgery without antibiotics?

By Liz Bawden, NODPA Rep and Newsletter Co-Editor

Added June 7, 2010.

Since the adoption of the new Pasture Rule, there has been some discussion about what it means to each of us at the farm level. One producer asked how many acres per cow would provide for a cow's yearly forage needs. Several farmers responded; some obviously had highly productive land -- they recommended 2 acres per cow to cover pasture and stored forage needs. Other producers had more modest recommendations at 3 acres per cow. And of course, more acreage would be needed to keep any additional heifers. One post highlighted the difference in land requirements when different pasturing systems are used: less land is required for intensive rotational systems.

There was some discussion on how the 30% rule would be applied over the grazing season. The answer from the training workshops hosted by the USDA is that the 30% figure is to be the minimum average over the grazing season. So a producer might graze 80% of the DMI in the peak months, and drop to below 30% in dry months; the months would be averaged out across the grazing season.

A farmer asked for help in her treatment of a fresh cow with milk fever symptoms. After the standard treatment of IV 23% calcium gluconate, the cow got up and was eating and drinking. The next day she was down and unable to rise, even after more calcium. Other producers chimed in with several suggestions: oral calcium products were suggested ("Dr. Register" was the brand, but be sure it is the formulation OK for organics), subcutaneous administration of calcium was suggested, CMPK products were suggested to balance a suspected magnesium deficiency (it was mentioned that magnesium oxide pills or epsom salts would also work). If the cow is an alert downer, and eating and drinking well, then it is very possible that it's a pinched nerve. It was suggested that a blood sample be drawn to test for her electrolyte balance. A potassium deficiency is rare, but can happen. To determine if it is a potassium deficiency, it was suggested to look for the classic "S-shape" in the cow's neck, and another producer checks the ears -- if the cow is down with warm ears. The good news: after several days of patience, extra minerals, and TLC, the cow got up on her own.

Two seasonal producers were dismayed to find some cows with a prolapse. A vet reminded us that "prolapse in an older cow is almost always due to milk fever, hence milk fever is always an emergency." If a prolapse happens on pasture, don't make the cow walk anywhere since it could easily rupture her vessels. It was suggested to use hobbles above each of the ankles and then attach a come-along to each hobble, drawing her legs backwards and rump up. Tie the tail up out of the way. Then go to work with a board underneath the uterus; take particular care in cleaning the uterus -- this is extremely important before you attempt reinsertion. Then work it back in, using only your knuckles so to not poke a hole through the uterine wall. It is extremely important to fully place the uterine horns back into their original position. Give the calcium IV afterwards and not before. Place iodine pills or Van Beek uterine pills for slow release to fight infection.

Some suggestions to avoid the possibility of prolapse included: 1) check the minerals that dry cows received, 2) make sure that cows and heifers stand up shortly after calving, 3) keep their hind end higher than the rest of them so that gravity doesn't work against you, 4) be aggressive to treat milk fever and follow up with CMPK when you think it may be needed, 5) consider the use of oxytocin to rapidly contract the uterus, if your milk company allows this (it is allowed by the NOP for calving issues). Homeopathic Secale may be of help as it is useful in restoring circulation in extremities and in smooth muscles. Longer-range suggestions were to monitor P levels in forage fed to dry cows.
Then a vet entered the idea that the fresh cow's calcium metabolism is controlled by the DCAD (Dietary Cation-Anion Difference) during the close-up dry period. Anionic salts such as magnesium sulfate (Epsom salts), calcium sulfate, and calcium chloride as used to acidify close-up cows. This will control milk fever, prolapses, retained placentas, metritis, displaced abomasums and ketosis.
The issue of determining the best way to provide just the right minerals brought about some great discussions about the pros and cons of free-choicing individual mineral components (That method is addressed in our article by Dr. Susan Beal on Free Choice Smorgasbord Vitamin and Mineral Supplementation for Livestock). Some members of the list felt that cows could not adequately address their deficiencies at a free-choice bar; other members felt that cows have to learn this skill, and that requires some time and experimentation.

The idea of surgery without antibiotics makes an organic farmer shudder with worry, but there was a lot of talk about just that this month. A producer wanted to have a stubborn case of hardware dealt with by surgery if it would be possible. A helpful vet encouraged her not to pursue surgery involving the stomach. Several other producers said they had had good results with DA's completed without antibiotics, even performed on-farm.