The DKC’s multidisciplinary team researches and brings management strategies that help dairy leaders to drive better business decisions.

The DKC’s  Management provides valuable knowledge in critical business areas such as nutrition and feeding, milking, reproduction, housing, and breeding practices.

Milk bottles

Prediction of enteric methane emissions from milk fatty acid profiles and dairy products

Andrés Haro

Enteric fermentation of ruminants is the main source of methane in the dairy industry that constitutes a loss of energy and contributes to greenhouse gas emissions. Direct quantification of greenhouse gas today is complex and requires high accuracy. Therefore, researchers are taking immediate action to reduce its impact.

Among the different methods used to indirectly measure methane enteric emissions in dairy cattle are predictions from the analysis of fatty acid profiles in milk, an easy method to be used in the field.

This content is locked

Login To Unlock The Content!
Tractors

Effects of compaction on silage quality of grass stored in bunker silos

Mercedes Gonzalez & Fernando Diaz

One of the key steps to achieve optimal quality during silage storage, is to extract the air to maximize anaerobic conditions necessary to promote a lactic fermentation of the chopped plants.

Air elimination is achieved by compacting the forage material by treading on top, usually with the use of heavy machinery. Compaction will be insufficient if the grass is not well cut and/or has excessive particle size, or if the equipment does not have enough weight per ton of forage.

This content is locked

Login To Unlock The Content!
Dairy cows

Milking robots offer similar performance on pasture systems

Alvaro Garcia

Finding, hiring, and retaining labor has in recent years become a problem for dairy farms across the world. Automated milking systems (AMS) are increasingly becoming popular since they solve this problem while increasing productivity, milking efficiency, and reducing the handling required in lactating dairy cows.

While these have been employed in confinement production systems with success its adoption in grazing systems still lags. The adoption in the traditional confinement systems has increased since its first introduction in the Netherlands in the early 90’s to an estimated 50,000 units on 25,000 farms in 2019.

It is even estimated that in Europe nearly half of dairy start-ups do so with AMS with some countries having an adoption rate of nearly 23%.

This content is locked

Login To Unlock The Content!
Dairy cows

Economics of dairy production systems with different types of pasture and breeds

Nuria Garcia

The elimination of quotas in the EU has led to a significant increase in milk production with more cows and higher yields per animal. In the case of Ireland, where there is a model based on grazing, many variables must be fine-tuned to achieve an optimal economic benefit. The type of pasture and the cow breed are among them.

Ryegrass is the most common species in wet climate areas as it is the most economical feed for dairy cows. A four-year study compared the economic performance of two types of perennial ryegrass (Lolium perenne L.) pasture planted with or without white clover (Trifolium repens L.). White clover is a legume and as such has the property of nitrogen fixation, so the nitrogen fertilizer needs of the soils are significantly reduced.

This content is locked

Login To Unlock The Content!
Farming

Extended colostrum feeding reduces health issues in young calves

Alvaro Garcia

Most colostrum is readily absorbed during the first hours of life, when the intestinal epithelium is still open to the passage of larger molecules (e.g., IgG, IgA, and IgM). Aside from its well-known effects on providing passive immunity through immunoglobulins, colostrum is an excellent source of nutrients with a much higher concentration compared with that of milk.

In addition, colostrum adds to what has been termed ‘metabolic programming’, which begins in-utero and continues after birth. Milk-borne bioactive factors transferred from the mother in early life, play a critical role in programming later life events through cellular signaling mechanisms, immunity, and growth and differentiation of the digestive tract.

This content is locked

Login To Unlock The Content!
Earth

Evolution of the environmental impact of dairy production

Joaquín Ventura and Fernando Díaz

Agricultural production in general and livestock farming of ruminants, including dairy production, has been associated with the generation of environmental impacts of different kinds: greenhouse gas production, resource consumption, soil and water pollution from animal excretions, visual impact on the landscape, etc.

Producers have strived for decades to minimize all these impacts, so that production is becoming more efficient and generates less environmental footprint, especially if you consider the impact per unit produced, in our case kgs of milk. First, it is more cost-effective to produce by consuming fewer resources, and second environmental awareness has grown greatly since the last third of the twentieth century, both by the producers themselves and by consumers.

This content is locked

Login To Unlock The Content!
Milking cows

Removing S. aureus from teat cup liners using automatic cluster flushing

Alvaro Garcia

Mastitis is an inflammation of the udder caused by microorganisms that enter the gland through the teat canal. Once inside the gland, these organisms find ideal conditions in which to multiply and, in turn damage the lining of the milk ducts, cistern, and alveoli. Contagious bacteria are spread from a cow with an infected udder to a healthy cow.

Transfer of pathogenic bacteria between cows usually occurs at milking time. Milker hands, towels, or the milking machine can all act as reservoirs for contagious bacteria. The major contagious pathogens are Streptococcus agalactiae, Staphylococcus aureus, and Mycoplasma spp.

The most important approach to minimize the transmission is to address potential sources of contagion at milking time. Cleaning the cluster between milkings has been used in commercial farms for quite some time. However, submerging the cluster in hot water (85°C) has been found not very effective in reducing the number of new intramammary infections.

Similarly, flushing has not achieved the complete eradication of new infections. Flushing with just cold water is frequently used in commercial farms since it is less costly, does not damage the equipment that much, and reduces the risk of residues in milk. Adding disinfectants to the water has also been explored as an alternative solution.

Using an iodine solution has been demonstrated to reduce intramammary infections by Corynebacterium bovis and coagulase-positive staphylococci. Given these results it seems that teat cleanliness, teat dipping, and an adequate milking routine are more effective in reducing the spread of infections than the attempts at washing or disinfecting the unit.

This content is locked

Login To Unlock The Content!
Sprinklers

Cooling cows leads to hormone secretion that increases milk production

Álvaro García

Heat stress in lactating dairy cows leads to physiological responses that affect their well-being and performance. The peculiarity of their digestive system leads to increased heat increment, which further compounds with external environmental warm temperatures.

To cope with this heat overload, cows rely on two main mechanisms. One internal, which is to reduce feed intake and thus heat production, the second external which is to look for cooler spots in the barn or the field. The heat overload affects several aspects of the animal’s physiology, ranging from reductions in productivity, reproductive losses, all the may to increased incidence of digestive upsets.

Dairy farmers in warmer climates tackle this problem with a few different approaches targeting both internal and external sources of heat. One frequent approach (external) is to cool-off cow’s through water sprinklers, forced air through fans or a combination of both. Another approach (internal) is to increase the nutrient density of the diet to account for reduced feed intake. Despite all these efforts there is still always a sensible reduction in intake, which results in a negative energy balance.

A negative energy balance causes hormonal changes such as a reduction in leptin and an increment in ghrelin

This disparity between energy intake and its requirements for production leads to hormonal changes responsible for further drops in intake. One such change is the reduction in leptin and an increase in ghrelin. Leptin synthesized in the adipose tissue has important bearing in eating behavior, energy expenditure, and body weight. It signals the hypothalamus of the adequacy of the energy status in the body, and the need to reduce intake.

This content is locked

Login To Unlock The Content!
Two cute Jersey calves

Which is the upper critical temperature-humidity index for dairy calves?

Alvaro Garcia

Thermostasis is the process by which warm-blooded animals keep their body temperature constant despite changes in environmental temperatures. Heat stress occurs when calves are incapable of dissipating enough heat to maintain their core body temperature below 38.5ºC. This increase in body temperature results from the combination of heat from the environment and that produced internally during nutrient metabolism.

In the northern hemisphere it is quite common for calves to be housed in polypropylene hutches with a small restricted outside area. During warm summer days calves seek the shade supplied by the hutch, however the heat inside of it will be concentrated. The calf then resorts to physiological mechanisms to lower its body temperature.

Under these conditions it is easy to verify an accelerated respiratory rate also accompanied by increases in rectal temperature, ear temperature, heart rate, and salivary cortisol (SC).

Ambient temperature and humidity determine the heat stress threshold

Not only is the absolute ambient temperature important but its combination with humidity in what is known as the temperature-humidity index (THI).

In adult cattle the upper critical value for this index is between 72 and 74, with some authors even considering up to 78 before respiratory rate and rectal temperature increase. In young calves however the optimum THI has not been determined, it is suspected however it should differ from a mature lactating cow since the heat increment resulting from forage fermentation in the rumen is very low, and the metabolic heat associated with milk production is non-existent.

This content is locked

Login To Unlock The Content!
A little herd of cute Holstein calves on the grass

Trace minerals injection increases immunity in young dairy calves

Alvaro Garcia

Diarrhea and respiratory disease are the two leading death losses in un-weaned heifer calves. Respiratory problems have increased in the last 20 years, causing more than 20% percent of all dairy calf losses. Heifers that survive continue to perform poorly as adult cows.

Calf deaths within the first 48 hours of life are significant and greatly influenced by nutrition, environment, and management. One of the most prevalent reason for these death losses is the inadequate passive transfer of immunity through colostrum received from the dam. Current guidelines suggest calves should receive 3–4 quarts of high-quality colostrum within 1 hour of birth and 3 additional quarts within the next 12 hours.

If colostrum ingestion is inadequate, esophageal feeders can be used making sure that 3–4 quarts are administered within 1 hour of birth. Pooling colostrum is also becoming popular with large farms because it increases the immune competence of the calves (or their ability to respond to a more diverse pool of pathogens).

Have you fed your calf enough colostrum?

One way to find out if colostrum has supplied adequate amounts of immunoglobulins (IgG) is to measure either IgG directly or serum total protein in blood serum. Serum total protein measured with a refractometer is highly correlated with serum IgG levels. Measuring serum total protein in a group of calves is more meaningful than individual readings; at least 80% of a group of calves should have serum protein levels of 5.5 g/dL or higher.

This content is locked

Login To Unlock The Content!