22 June Summer Feeding Update July 2011 Bulletin Richard Keel

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1 22 June 2011 Summer Feeding Update July 2011 Bulletin Richard Keel 10

2 Summer Calvers - Focus on Dry Cow Management Ultimately dry cows are the dairy farmer s future income. There has been much discussion in recent years with regards to nutritional options around feeding transition dry cows. Over the years several nutritional systems have been developed with varying degrees of success on farm. Body condition scoring (BCS) is a great tool to understand and predict likely problems during the dry period and feeding a late lactation group of dairy cows correctly can help negate BCS problems at drying off and during the dry period Thin OK Fat Dry Matter Intake % of Bodyweight Days Pre-Calving Common Dry Cow Pitfalls 1. Unobserved dry cows 2. Poor nutrition and housing 3. Irregular feeding patterns 4. Unplanned drying off procedures 5. Poor quality forage (too much grass is often bad for dry cows) & low DMI pre/post calving 6. Reduced immunosuppression at calving Ketosis and fatty liver has become more common around calving reflecting a lack of energy supply in late pregnancy or a lack of a particular energy source. Also a lack of available calcium at calving has encouraged increased incidences of retained placentas and metritis and in severe cases milk fever. TMR Dry Cow Mineral Feeding Systems There are three main feeding systems in the UK, and all potentially have a place. At Feed Supplements we have taken the approach of tailoring a system that is suitable for most farmers to easily use and manage, one of the main pitfalls. System Typical Target Calcium Levels Guideline Blood ph TMR Palatability Factor Traditional Calcium Starvation 25 28g 8.0 Good Approach Partial DCAB 65 80g Good Full DCAB 150g+ 6.0 Poor Remember that on full DCAB diets, close up Jersey cows often need a lower ph than Holstein breeds (source Goff et al) for effective control of milk fever typically ( )

3 The partial DCAB nutritional approach has been gaining popularity recently with customers. A half way house approach across other systems, easy for the farmer to manage, we see fewer full DCAB approaches on farm now due to the difficulty and high management requirements needed to make the system work successfully knife edge scenarios. Calcium is a critical element for calving cows due to the x5 fold increase in requirement at calving. There are many different sources of calcium available to use in ruminant mineral supplements ranging from calcium chloride, calcium sulphate, calcium propionate and calcium carbonate, to name four. Calcium is required for muscle function, the rumen and uterus being two key muscles at calving. It has become more common to see late lactation cow s diets low in phosphorus (last 60 days of lactation especially) as mineral supplements generally contain lower levels of phosphorus to balance early/ mid lactation diets phosphorus was quite often over fed in the 1 st 150 days (source Wu et al) a difficult conundrum for the mineral advisor on farm. This then leads to incorrectly balanced calcium: phosphorus ratios in the diet. Signs of a Failing Dry Cow Regime Preparing the rumen so that high energy feeds and protein supplements can be fed to meet the early lactation requirements is critical. Stimulating the growth of lactate metabolising bacteria is key to optimising performance. Dry cow mineral nutrition is critical to meeting these demands post calving. Estimated Cost/Case (source Kingshay Health Manager 2011) 1. Retained cleansings 300/case 2. Whites (metritis) 170/case 3. Fatty liver/ketosis unknown 4. Clinical/sub clinical milk fever 220/case 5. Fresh calver mastitis 220/case 6. Displaced abomasums 250/case 7. Poor rumen function post calving unknown Key Mineral Nutrients For Dry Cows Nutrient Function Deficiency Symptom Magnesium Muscle function & nervous system Antagonised by potassium, poorly stored, leads to milk fever Vitamin E Antioxidant, immune function, hormonal activity Retained cleansings, low immunity status, increased incidence of mastitis, muscle damage Calcium Rumen & uterine muscle Retained cleansings, milk fever, delayed calvings, strength Selenium Antioxidant, immune function Low immunity status, increased incidence of mastitis, muscle damage, low fertility status Vitamin D3 Regulation of calcium, Milk fever magnesium & phosphorus within the body Iodine Thyroxine production involved in energy Prolonged calvings, weak/still born calves, retained placentas, metritis metabolism regulation Phosphorus Energy metabolism Milk fever, reduced appetite, poor fertility status Chloride DCAB manipulation Helps control ph in blood & urine to enable a successful partial DCAB system Sulphur DCAB manipulation Helps control ph in blood & urine to enable a successful partial DCAB system

4 Partial DCAB Systems The level and balance of potassium and other minerals which affect the acid or alkaline nature of the cow is expressed in terms of Cation-Anion Balance or CAB for short. Using CAB as a measure, all feeds thus have a rating for suitability for dry cows and are best viewed like a set of traffic lights with feeds on the Red list being the worst offenders and most likely to cause milk fever and associated conditions. Avoid these feeds if possible. These would include grass silage (especially if high CAB), grazed grass and caustic grain. Amber list feeds: have medium CAB values and are more suitable for dry cows. These would include maize silage, whole crop and straw. Green list : These feeds have low or very low CAB values and are highly suitable for dry cows and very useful to use to dilute the CAB value of the overall ration and would include cereals, brewers grains and rape meal. To summarise it is clear is that dry cows fed on grass or grass silage are significantly more susceptible to milk fever and associated conditions than those on maize silage, wholecrop and straw. Partial DCAB 400 Mineral Supplement Taking on board this understanding, Feed Supplements introduced our partial DCAB mineral supplement PDC400 around this time last year. The success of the product has gone from strength to strength with customers from across the country reporting significant benefits in terms of reduced milk fever & retained cleansings, less metritis and associated conditions. When fed at 400g/hd/day, PDC400 has a significant negative CAB value and thus plays a key role in helping to offset the CAB value of the total diet. PDC 400 supplies a specific range of calcium salts and has a specific anionic salt pack to ensure success on farm.

5 Summary Points 1. Now is the time to discuss dry cow management and nutrition with dairy farmers 2. Check the grazing pasture the dry cows are feeding are the cows being overfed grass? 3. Understand what the existing system is and how it is performing 4. Can the dry cows be housed? 5. If a mineral supplement is being fed, look at the declaration ticket and assess what the existing approach many farmers will be unsure! 6. ID what problems may exist 7. Understand the practical limitations facing the farm management system 8. Look to propose where improvements can be made 9. Consider a partial DCAB approach where appropriate 10. Adding a proven anionic salt pack can help counteract the effects that dietary potassium & sodium have on the blood ph of transition dry cows 11. Where problems arise, expensive oral calcium based bolus s containing calcium chloride and calcium sulphate are used (Bovicalc) time to discuss our partial DCAB PDC400 mineral! 12. Consider using specialist rumen protected feed additives such as carnitine, choline & niacin where appropriate. If you have any questions or require further information with regards to this article, please feel free to call me accordingly. Richard Keel Business Manager Feed Supplements Mineral Division Car