Glossary: dairy cattle terms

An age at first calving of 23 to 25 months is the usual target. Every extra month costs feed and space, and at the same replacement rate you need to rear more youngstock. In the German state of Schleswig-Holstein the average in 2024 was 27.2 months. An early AFC depends on good daily gains from the calf stage onwards.

Allicin forms when alliin and the enzyme alliinase come together as a garlic clove is cut or crushed. The substance is highly reactive and breaks down within hours. Boluses therefore use stable derivatives such as PTS and PTSO. Read more in the Udder bolus white paper.

Antioxidants neutralise free radicals, which form during stress, inflammation and high metabolic activity. In cows the main ones are vitamin E, selenium and vitamin A. Around calving the requirement is high, and a deficiency is linked to udder oedema and weaker immune defences.

For a milk culture, you first clean the teat thoroughly. You then take a sterile quarter milk sample, which the laboratory cultures. The result shows whether a cow-associated or an environmental pathogen is involved, and so where to start on your farm. On-farm quick tests can at least tell Gram-positive from Gram-negative pathogens.

Cows produce large amounts of sodium bicarbonate in their saliva, which buffers the acids in the rumen. A cow that ruminates a lot buffers a lot. In hot weather cows lose saliva through panting, and with it buffer. In electrolyte drinks for calves with diarrhoea, sodium bicarbonate is the main ingredient that offsets acidification of the blood.

Biotin is produced by microbes in the rumen. Rumen acidosis or heat stress reduces this production, and high-yielding cows may then get too little. A deficiency makes the horn softer and raises the risk of white line defects and sole ulcers.

A bolus is given with a bolus gun and stays in the rumen or reticulum. Depending on its design, it releases its contents within hours or steadily over weeks and months. The advantage over lick buckets is that every animal reliably takes in a known amount. The plural is boluses.

The refractometer measures how strongly a drop of colostrum bends light. This gives the Brix value as a percentage, which is linked to the immunoglobulin content. 22 percent is considered good, 25 percent or more very good. If the value is lower, the colostrum should be enriched or replaced.

About 99 percent of the calcium is stored in the bones. Once milk production starts, the cow suddenly needs many times more, and releasing calcium from the bones only gets going after a delay. Older cows find this harder. In the dry period, the ration contains little calcium instead, so the cow learns to release it herself. More in calcium supply and milk fever.

Diarrhoea causes more than half of calf losses before weaning. The pathogens are rotavirus and coronavirus, E. coli and cryptosporidia, often in combination. One case costs 75 to 145 euros in direct costs and slows growth for about a week. You can read more about causes and approach in Calf diarrhoea? 5 steps to stay ahead of leaky gut.

With calving, the cow starts a new lactation. The weeks before and after calving are called the transition period. During this time the need for energy and calcium rises faster than feed intake, so metabolic disorders such as milk fever and ketosis are more common in this period.

The cell count covers epithelial cells and white blood cells. Below 100,000 cells per ml a quarter is considered healthy. Above 250,000 in cows and 150,000 in heifers it is considered subclinically infected. A cow with 300,000 cells gives about 5 percent less milk.

In the close-up phase the dry cow ration is adjusted towards lactation and the cow is ideally fed in a separate group. The phase should last at least 14 days. This is also when measures that lower the risk of milk fever come in, such as a low-potassium ration and a low DCAB. Talk to your nutritionist about the composition of the ration.

Colostrum contains immunoglobulins, fat, protein and growth factors. The calf should get 3 to 4 litres within the first hour and about 6 litres on the first day. You can check the quality with a refractometer using the Brix value. More in Colostrum management; for the right start!.

During an inflammation, more sodium and chloride get into the milk and its conductivity rises. Milking robots and many milking parlours measure it per quarter at every milking. A rise of more than 30 percent above the cow's own average is taken as a sign of a new case of mastitis.

Copper is bound by molybdenum, sulphur and iron, so the content in the ration alone is not a reliable measure. A deficiency shows as weak immunity, fertility problems and a pale, rough coat. Sheep are sensitive to too much copper.

Cow-associated pathogens include Staphylococcus aureus and Streptococcus agalactiae. The infected cow is the source. They spread via the milking cluster, hands and liners. Measures include a set milking order, teat dipping and culling chronically infected cows.

Cryptosporidium parvum usually infects calves in their first to fourth week of life and damages the intestinal villi. Yellow-green, watery diarrhoea is typical, often together with viruses or E. coli. The oocysts are very hardy, so hygiene and low infection pressure matter most. More in Tackling crypto in calves in 5 steps.

DCAB compares positively charged minerals (mainly sodium and potassium) with negatively charged ones (chloride and sulphur) and is expressed in meq per kg dry matter. A low DCAB in the close-up phase, just before calving, makes the blood slightly more acidic and prompts the cow to release calcium from her bones. The effect can be followed through urine pH. Talk to your nutritionist about the DCAB of your ration and whether a forage analysis would help.

The most common cause is milk fever. If the cow does not get up despite a calcium infusion, phosphorus deficiency, magnesium deficiency, fatty liver or nerve damage from pressure may be the cause. If she is still down after 24 hours, it is called downer cow syndrome. You can read more about causes and care in Calved; Why doesn't my cow get up?

When drenching, you usually give 40 to 60 litres of lukewarm water, often with energy and minerals, into the rumen through a tube and pump. This can help fresh cows or sick cows that drink and eat too little. Passing the tube takes practice. You can read more in The advantages of drenching.

When you dry a cow off, milking stops. The udder shrinks back and rebuilds for the next lactation. During this time the calf grows fastest and the cow lays the foundation for colostrum quality and a good start to lactation. The dry period is split into the far-off phase and the close-up phase. Read more in Better calves through optimal nutrition in the dry period.

Escherichia coli is found in faeces and reaches the teat via bedding and manure. Coli mastitis is often acute with fever, but with good immunity it often clears up on its own. In calves, E. coli is one of the typical causes of diarrhoea in the first days of life. As a gram-negative bacterium, it responds differently to treatment than staphylococci.

A calf with diarrhoea loses water and salts. At a loss of 6 to 8 percent, a pinched skin fold stays standing. An electrolyte drink replaces both and contains buffers for the acid-base balance. You give it between milk feeds and keep feeding milk as normal.

They include E. coli, Klebsiella and Streptococcus uberis. They come from the cow's surroundings, not from other udders. Dry, clean cubicles, good bedding and ventilation help keep them down. Around drying off and calving, the udder is particularly susceptible to them.

The FPR is calculated from milk recording or robot data. A value above 1.4 in the first weeks of lactation points to heavy breakdown of body fat and a risk of ketosis. A value below 1.0 suggests too little structure (effective fibre) in the ration and possible rumen acidosis.

If a cow breaks down more fat than her liver can process, the rest is stored in the liver. The liver then works less well, and ketosis and poor appetite reinforce each other. Overconditioned cows are most at risk. Severe cases are hard to treat, so prevention through dry cow feeding counts for more.

Feed intake limits how much energy the cow gets. It drops shortly before calving, and after calving it rises more slowly than milk yield. This causes the negative energy balance. In the first 60 days of lactation, 2.5 to 2.8 kg dry matter per 100 kg body weight is a guide value. Milking robots and neck collars show eating time as an early warning sign.

In a field trial, animals on ordinary farms are split into a test group and a control group, and data such as milk yield or rumination activity are compared. The results reflect everyday practice, but animal numbers are often small. The p-value tells you whether a difference is statistically significant, usually with a cut-off of 0.05.

Forage supplies most of the dry matter and the structural fibre in the ration. Its quality varies with cutting date, weather and fertilisation, so it pays to have your forage analysed regularly for energy, protein and minerals. What the forage does not supply is made up by concentrates or a mineral feed.

Ruminants absorb hardly any sugar from the gut, because the rumen microbes ferment it first. The liver therefore builds glucose itself, mainly from propionic acid produced in the rumen. Substances used for this are called glucogenic, for example propylene glycol, propionate and glycerol.

At turnout the ration changes within a few days. Young grass is rich in protein and potassium but often low in magnesium, selenium, copper and cobalt. A gradual transition with roughage and a reliable mineral supply help prevent grass tetany and deficiencies.

Cows are most comfortable between -5 °C and 18 °C. Above that they eat less, up to 22 percent, lose buffer through panting and show higher cell counts. Heat stress in the dry period lowers milk yield over the whole following lactation. Measures include ventilation, shade, water and feeding several times a day.

In functional hoof trimming the horn is cut so that the inner and outer claw carry the same weight. This also helps you spot problems early. Housed cattle need it at least three times a year.

Immunoglobulins are antibodies. The cow does not pass them on through the placenta, so the calf is born without protection and has to get them from colostrum. The gut absorbs them well only in the first hours of life. The most important group in colostrum is IgG. You can estimate its content with the Brix value.

Ketosis develops from a negative energy balance, when the liver can no longer cope with the breakdown of body fat. The subclinical form only shows up in BHB measurements. In the clinical form, cows lose appetite, lose weight and sometimes smell of acetone. The cost is estimated at 250 to 600 euros per case. Read more in Ketosis causes major expenses.

A lactation starts at calving, reaches peak yield after about 6 to 8 weeks and ends at drying off. The dry period then follows before the next calving. The number of lactations a cow completes is a measure of her productive lifespan.

Lameness is one of the most common reasons for culling. Lame cows lie down for longer, go to the feed fence less often and give less milk. The usual causes are sole ulcers, white line defects or Mortellaro. Regular hoof trimming picks these up early.

With clinical mastitis you see flakes, watery milk or a hot, swollen quarter. You can only detect the subclinical form through the cell count or conductivity. It is 15 to 40 times more common. A clinical case can easily cost 300 to 500 euros.

How a calf grows in its first eight to ten weeks helps determine how much milk it gives as a cow. Every extra gram of daily gain before weaning brings around 4 litres of milk in the first lactation. Generous milk feeding and healthy calves are the basis for this. More in Metabolic programming of calves.

Metritis occurs mainly after difficult calvings and retained placenta. Typical signs are foul-smelling discharge, fever and lower feed intake. Cows with milk fever or ketosis are affected more often. Diagnosis and treatment are a matter for your vet.

When milk production starts, the cow loses more calcium than she can replace from feed and bone. In clinical milk fever she goes down and cannot get up. In subclinical milk fever only the low calcium level in the blood shows, followed by more mastitis, displaced abomasum and ketosis. Older cows are affected more often. More in Calcium deficiency in cows, a huge cost.

The milk recording report shows milk yield, fat, protein, urea and cell count for each cow. Sort it by cell count and you find the cows that push up the bulk tank cell count. From fat and protein you can calculate the fat-to-protein ratio, an indication of ketosis or rumen acidosis.

After calving, milk yield rises faster than feed intake. The cow covers the gap from body fat. Up to a point this is normal, but she should lose no more than one BCS point. Between day 50 and day 60 of lactation the balance should be level again. If the deficit gets too deep, ketosis and fatty liver follow.

After calving, blood phosphorus drops in many cows, because the milk takes a lot of it out of the body and feed intake is low. Milder forms show up as poor appetite. Cows that do not get up despite calcium often also have a phosphorus deficiency. How much phosphorus the dry cow ration should contain is something to discuss with your nutritionist.

Potassium raises the DCAB of the ration and inhibits magnesium absorption in the rumen. Fertilised grassland and grass silage often contain a lot of it. That is why potassium is kept low in the dry period. Talk to your nutritionist about how to achieve this in the ration. Potassium also holds water in the tissue and encourages udder oedema.

A dairy cow in Germany and the Netherlands averages about three lactations. Most culls are involuntary, due to fertility problems, mastitis or claw problems. Each extra lactation lowers the rearing cost per litre of milk. There is a worked example in Aim for two more lactations.

Propionic acid is formed in the rumen when starch is fermented and is the main building block for glucose. As a salt (propionate) or as propylene glycol it is given to freshly calved cows to narrow the energy gap. Propylene glycol works, but cows often take it poorly because of its taste.

The placenta normally comes away a few hours after calving. If it stays in longer, the risk of metritis and fertility problems rises. Difficult calvings, calcium deficiency and a poor supply of selenium and vitamin E make it more likely.

A healthy cow ruminates for about eight hours a day. Collar or ear sensors measure this in minutes per day. A drop in rumination time is often the first sign of reduced appetite, rumen problems or an emerging illness, usually before you see visible symptoms. Field trials use it as a measure of vitality after calving.

Instead of drying off every cow with antibiotics, you decide based on the last milk recording. Cows with a cell count below 150,000 (first-lactation heifers below 100,000) and no clinical mastitis only get an internal teat sealant. Under EU rules, antibiotics may not be used routinely, and that includes drying off.

Selenium is part of antioxidant enzymes. A deficiency weakens the defences in the udder, increases the risk of retained placenta and causes muscle weakness and reluctance to drink in calves. Many soils are low in selenium, so grazed grass often does not cover the requirement. Too much selenium is toxic, so only supplement it in known amounts.

Staphylococcus aureus is one of the most common mastitis pathogens. It spreads during milking and forms pockets of infection in the tissue that often survive treatment. Fluctuating high cell counts are typical. Chronically infected cows are a source of infection for the whole herd, so culling is often the answer.

Streptococcus uberis lives in bedding and manure and is classed as environmental. Streptococcus agalactiae, by contrast, lives in the udder and spreads during milking, but has become rare on many farms. Both are gram-positive. A bacteriological test shows which pathogen is present.

Subclinical forms of mastitis, ketosis or milk fever are far more common than the clinical ones. The cow looks healthy but gives less milk and is more likely to develop other conditions as a result. The only way to find them is to measure. You can find examples in Clinical and subclinical symptoms.

A sphincter muscle and a keratin plug keep the teat canal closed between milkings. After milking it stays open for a while, which is why teats are dipped and the cow should stand and eat afterwards. During the dry period, an internal teat sealant can close the canal.

Teat cup liners age, become rough and lose their tension. As a rule of thumb, replace them after about 2,500 milkings for rubber and 10,000 for silicone. Worn liners damage the teat ends and spread pathogens.

After the cluster is removed, the teat canal is still open. A teat dip reduces the number of germs on the teat skin and cares for the skin. Above all, it limits the spread of contagious, cow-associated pathogens from cow to cow. It only works if you dip every teat at every milking.

In a TMR, every cow gets the same mix of forage, concentrate and minerals in every mouthful. This keeps the rumen stable. To stop cows from sorting, the straw must not be too long and the mix must not be too dry. Often a partial TMR is fed, with concentrate topped up according to yield at the out-of-parlour feeder or in the robot.

In the transition period the cow moves from pregnancy into lactation. Feed intake, hormones and immunity change within a few days. Most metabolic disorders and new udder infections occur in this period, which is why they are also called transition diseases.

In udder oedema, tissue fluid builds up because blood flow rises sharply before calving and drainage cannot keep up. The udder is tight and cool, pressing with your thumb leaves a dent, and the milk is normal. Mild oedema goes down within one to two weeks.

Udder parenchyma consists of the alveoli, the small glands in which milk is produced. It starts to develop in the calf's first weeks of life. Calves fed generously on milk have been shown to develop more of it, which is part of metabolic programming.

Fresh grass contains plenty of vitamin E, while silage and hay contain much less. Dry cows kept indoors are therefore often short of it, even though their requirement rises around calving. A deficiency is linked with retained placenta, udder oedema and more mastitis.

At weaning you reduce the milk feeding step by step until the calf lives on calf starter, hay and water. For this to work, the rumen must already be well developed. Through metabolic programming, the weeks before weaning shape the calf's later milk yield.

The withdrawal period is set in the marketing authorisation of a veterinary medicine, separately for milk and meat. Complementary and dietetic feeds have no withdrawal period, because they are not medicines. If in doubt, ask your vet.

Zinc is needed to form keratin, and so for firm claw horn and tight teat skin. A deficiency weakens the immune defence and slows wound healing. Sick calves have measurably less zinc in their blood than healthy calves.