Managing your dairy herd and youngstock this autumn and winter

When planning for feeding over autumn and winter, it is essential to determine how much forage you currently have. Measure silage clamps and count the number of silage bales in the yard and see how much good quality straw you can get hold of. Contact your local feed advisor to assist you with measuring silage pits and estimating silage quantity and preparing autumn and winter feeding plans for your farm if needed.

To make up for current deficits in silage stocks, growing a third cut of silage will be critical for many farms (budget on yields of 6 ton per acres when doing your budget). If this is still not enough, straw-based diets can form a significant portion of winter diets in these circumstances if sufficient straw is available. Alternative sources of forage for the autumn are fast-growing grasses, or forage rape or kale that have been planted in stubbles and, depending on the individual crop, these can be used for baling, pitting, or extending the grazing season.

Finishing stock and young stock may need to be housed now in order to facilitate the growing of a third cut in the fields. Housed young stock will do well on a straw-based diet with a mix of concentrates and a minimal amount of silage so long as it is mixed and fed correctly.

Regardless of whether these animals need to be housed or not now, straw and concentrate-based diets for young stock can significantly save on silage demand through the winter, while still maintaining growth rates, and high straw diets also work well for dry cows, further reducing the demand on silage.

Sample Diet for Calves, Dry Cows and In-Calf Heifers

 Based on the following animals:

*Holstein / British Friesian weighing 620 kg and eating 12.5 kg DM / day as a dry cow. Not gaining or losing weight at BCS 3.0

*280 kg calves growing at 0.8 kg / day

*520 kg in-calf heifers growing at 0.8 kg / day

*Silage - 70 DMD, 30% DM & 14% crude protein

*Concentrate on a fresh weight basis – 21% crude protein, 34% starch and sugars and composed of maize, barley, soya, rapeseed, sugar beet pulp, rapeseed extract, soya hulls, distiller’s grains, molasses and 1kg / ton of Actisaf live yeast.

Things to remember when feeding straw-based diets

• If a diet feeder is incapable of chopping straw, then straw can be pre-chopped using a straw chopper or forage harvester. Straw should be ideally chopped to 2-4” long (muzzle width of the animal)
• Have your diet feeder serviced over the coming months if it has not been serviced already and ensure that all knives are sharp and installed properly.
• Water may need to be added to the diet feeder mix in order to keep the mix moist and minimise sorting if drier silages are being fed with straw and concentrate. Aim for 45% dry matter in the overall mix.
• Adding molasses to drier diets will aid against sorting and increase palatability but be careful not to overfeed it as it is high in sugar.

High DMD grass silage, whole crop cereals and maize silage should be prioritised for cows post-calving in the spring with lower DMD grass silage being fed to dry cows once they are in the correct condition score at drying off. However, if a fodder budget shows a serious deficit and this is not filled by winter, a proportion of the dry cow and young stock diets can be supplemented with either whole crop or maize silage, along with grass silage, and balanced accordingly.

Be sure to get your forage analysed.Do not ignore carrying out this task this year as knowing the quality of forage in the yard is as important as having quantity in the yard.

If you simply haven’t got enough silage and straw, and can’t get more, then the next step is to decide how many animals will be retained through the winter. Cull cows that are not in calf, any that are lame, have high SCC and repeat mastitis offenders. This will optimise overall herd health and improve returns, whilst reducing forage requirements and feed costs. Having done all of this, if a major deficit still exists, selling off productive milking cows or young stock will be a last resort.

Current recommendations for dairy herds

While looking ahead to the winter is very important to do right now, the current priority for dairy farmers will be feeding milking cows and maintaining milk solids production. It is vitally important that everything possible is done to maintain persistency of production through the autumn and into the early winter in order to maintain a steady revenue stream. A target of a drop off in milk solids yield of 2.5% per week or 10% per month is a good benchmark to use. In practice this means that a cow that was yielding 25 litres in mid-August should be yielding 22.5 litres by mid-September.

Grass growth has increased in recent weeks and covers have bulked up and, as a result, the pressure on supplementary buffer feeding of silage and soya hulls has decreased somewhat. However, the reality is that cows still require a substantial amount of concentrate through the milking parlour over the coming weeks so as to manage the grass demand per hectare relative to growth rates so that grass covers can be built up for grazing during the back end.  

For example, if a farm is stocked at 3.25 cows / Ha on the milking platform and a farmer allocates 14.5 kg DM of grass/cow/day with a predicted 90% utilisation, the demand is almost 48 kg DM/Ha/day. If growth rates of 60 kg DM/Ha are achieved over the coming weeks, the average farm cover could potentially be increased by 250 kg DM/Ha within three weeks. This will require an 8 kg parlour feed rate for a 620 kg cow producing 1.9 kg of milk solids per day at 25 litres at 4.1% fat & 3.45% protein.

Depending on each individual farm’s circumstances, and what the current average farm cover is, it may be possible to achieve the recommended average farm cover of 1,100 kg DM / Ha by mid-September by continuing to feed 8 kg of concentrate through the parlour and limiting grass demand to approximately 48 kg DM/Ha/day. It is a good calculation to do if you have not done so already. If grass growth is lower or if the stocking rate is higher on the milking platform, then silage, soya hulls or both will probably need to be kept in the diet until the desired average farm cover is achieved. Keeping an eye on the costs of production, in particular income over feed costs, will be important over the coming months, therefore maintaining persistency of production will be so critical.

Feed cost analysis of dietary options to sustain 25 litres at 4.1% butterfat and 3.45% protein or 1.9 kg of milk solids

*620 kg Holstein / British Friesian cow eating approximately 20 kg DM / day

*70 DMD silage at 30% DM and 14% crude protein

*Silage cost €65 / ton fresh weight                                 *Straw cost €140 / ton fresh weight

*Soya hulls cost €200 / ton fresh weight                         *15% crude protein compound feed costing €300 / ton

*Grass cost 10 cent / kg DM                                            *Milk price of €4.35 / kg milk solids                               

Managing rumen function and avoiding issues with acidosis

Be extremely alert to the risk of acidosis when feeding higher levels of concentrate this autumn, particularly over the coming weeks when lush and leafy grass swards come back into the diet. Sub-acute rumen acidosis will reduce intakes, milk solids yield and fertility and can result in inflammation and lameness, whilst in its clinical form acidosis can kill animals. The following tips will help you best manage the risk of acidosis in your herd:

• Feed a maximum of 8 kg of concentrate through the parlour. If more is required, it should be at a head feed in collecting yards. Do not feed more that 50% concentrate in total in the diet.
• Make changes to the diet slowly and feed concentrates as consistently as possible. Feeding higher starch rations because of higher cereal levels in feed will require careful feed management and increased attention to detail. Work with your feed advisor on purchasing the best compound feed formulation for your herd’s individual circumstances
• Observe cow signals for signs of acidosis, such as loose dung with gas bubbles and undigested fibres and grains visible. Other warning signs include poor rumen fill and empty looking cows, cud balls in collecting yards, poor cudding rates, and cows losing body condition.
• Feeding Actisaf live yeast will significantly reduce the risk of acidosis this autumn and simultaneously increase the feed conversion efficiency of you herd, helping them to produce more milk solids from the same amount of feed.

Actisaf is the only live yeast scientifically proven to reduce lactic acid levels in the rumen (which accumulates and causes acidosis), and published research in the Journal of Dairy Science has shown it to lower lactic acid levels to a greater extent than sodium bicarbonate (bread soda). It also increases fibre digestion in the rumen, unlocking more energy from silages and increasing herd performance.

Actisaf live yeast can be included in your compound feed, blends and coarse ration by your local feed mill at a rate of 1 kg per ton for a 6- 8 kg feed rate, costing €10 / ton. For farmers using diet feeders it can be included via 25 kg farm pack.