Dairy Cattle Feeding Management: TMR Feed Formulation for Lactating Cows

Feeding dairy cows is vital in ensuring maximum production. However, genetics, health, and herd management should not be overlooked. Although genes have improved over time and continue to improve, feeding also has evolved. It is possible nowadays to offer precision-formulated feed to maximize production per animal. 

Many farms have adopted total mixed rations (TMR) since it offers the right amount of nutrients lactating cows need. Additionally, it’s easy to formulate and optimize ration depending on the cow production and other requirements. 

In this article, we will learn about dairy cattle feeding management through TMR feed formulation for lactating cows. 

Importance of Good Dairy Cattle Feeding

Feeding the right amount and nutrients is one way to keep animals healthy. Also, well-formulated feed ensures that cows achieve maximum production. The following are two main benefits of feeding dairy cattle the correct ration. 

a) Well-maintained animals are healthy: Providing feed with all nutrients ensures your animals are healthy. Quality feed should provide proteins, minerals, vitamins, and other essential nutrients to strengthen the animal's ability to resist diseases. 

Feeding a lactating cow should ensure that the ration provides enough nutrients for ideal body maintenance and production. Animal health might be compromised if the ration doesn’t meet these conditions and might suffer from various conditions like;

• Milk fever/ Hypocalcaemia
• Subacute ruminal acidosis (SARA)
• Emaciation and low fertility
• Retained placenta 
• Udder edema 
• Metritis 

b) Proper feeding ensures maximum milk production: Besides keeping animals healthy, feeding balanced feed facilitates maximum production. Nutrition should focus on these, lactation stage, production level, and animal body size. Formulating feed with all requirements is therefore essential. 

Pre and Post-partum Nutritional Requirements for Dairy Cows 

Nutrient requirements for animal changes depending on the lactation stage. Knowing when and how to adjust feed is crucial for dairy cattle farmers to provide the right nutrients. 

a) Energy 

Energy mainly comes from carbohydrates which 70% of all nutrients. Cattle feed contains more carbohydrates than the rest of the nutrients. The energy demand depends on the size, age, and production level. 

To ensure the ration meets the required amount of energy, dry matter should be able to provide enough carbohydrates. Therefore, the daily DM requirements should be based on animal weight and milk production. 

During the early lactation period (0-100 days), the cow is at the production peak; the energy demand is also at the peak. Since the feed can’t supply the needed energy effectively, the body will metabolize the reserved energy during the pregnancy. This leads to declining cow body weight. 

In the mid-lactation period (100-200 days), animal milk production is slightly declining. During this phase, the feed should be able to cater to animal maintenance and milk production. At the same time, the energy demand is a bit lower than in early lactation. The dry matter intake is at the maximum in this phase. 

During late lactation (200-305 days), milk production is at its lowest, and energy requirements decline. At this phase, it's advisable not to overfeed the animals. At this point, the cow is pregnant and building the weight lost during the early lactation phase. 

The dry period (60 days to calving) is the pre-parturition period, where the cow is building its energy reserves. Proper feeding is vital for the cow and fetus. Giving the cows 2% DM of the body weight is recommended. Also, the crude protein should be at 12.6% while maintaining a proper mineral and vitamin supply. 

b) Proteins 

Proteins are the second most essential nutrient after carbohydrates. They should be supplied in the correct amount during the lactation period. The protein intake for cows is expressed in Crude protein (CP). 

The protein requirements, like energy needs, depend on the production. During the early lactation stage, the animal will consume about 17-19% CP of total DM. The requirements for proteins decrease in the mid-lactation stage to 15-16% and to 13-15% in the late lactation stage. 

On dry cows, the protein requirement should be maintained between 13-14%. Feeding dairy cows with less than 12% CP can negatively impact milk production, colostrum quality, and other effects. 

c) Fat 

Fats are an excellent source of energy. They have more energy per unit compared to carbohydrates and proteins. Providing fat in the feed is essential since it plugs the energy deficit. However, farmers should be cautious about the amount of fat in feed. As a rule of thumb, experts recommend that fat should not be more than 7% composition of DM. 

Ideally, fat should be 5-6% during early lactation. Mid-lactation should be 4-6% and 3-5% late lactation. On dry cows, fat should be maintained at around 1.8-2%. 

d) Minerals 

Lactating cows require plenty of vital minerals in their feed. They play crucial roles in the productivity and health of dairy animals. Farmers must closely monitor the availability of essential minerals like; calcium, phosphorus, potassium, Sodium, sulfur, Copper, Manganese, Cobalt, and Zinc. 

When formulating a ration, it should contain the right minerals depending on the production stage of the dairy cattle. Below is a summary of mineral requirements for lactating animals.

Table 1.1: Mineral requirements for lactating cows at different stages.  (See source)

e) Vitamins 

Just like other minerals, Vitamins are equally essential. They are important in a variety of animal body functions. Some include gene regulation, antioxidants, blood clotting, and others. When formulating a TMR feed, ensure adequate vitamins, as summarized below. 

Table 1.2: Vitamin requirements for dairy cows during lactation period (Source)  

Feeding Dairy Cattle TMR Feeds

What is TMR?

The total mixed ratios is not a new technique; it has been used since the 1950s. It is a precision feeding method where fodder, concentrates, and supplements are mixed in measured proportions to deliver the required nutrients. 

The feeding mode is mainly adopted in countries where dairy farming is done indoors. All the ingredients are mixed at the farm; therefore, commercial feeds are unnecessary. 

Is it advisable to feed TMR to dairy cows? 

Feeding dairy cattle, TMR comes with many benefits and also has downsides. Therefore, before embarking on the technique, it's best to evaluate whether advantages outrun disadvantages. 

Advantages of TMR

1. It is rumen friendly by maintaining a pH above 6.0. 
2. Sustainable since it uses readily available fodder. 
3. Easy to customize nutrients depending on the herd group.
4. Improves milk quality by adjusting components like fat and vitamins. 
5. Improved feed intake by reducing sorting and increasing palatability. 
6. It’s simple to mechanize the formulation and feeding process. 
7. Animals eat fixed amounts which reduces feed wastage. 

Disadvantages of TMR 

• Not easy to formulate feed for each cow; it's ideal only for a group of animals. 
• Requires large and expensive mixing machines
• Slight errors in ingredient calculation affect the whole feeding herd.
• The process is labor intensive as it requires chopping fodder into small particles. Dry hay and straws might be challenging to chop. 

Qualities of a Good TMR Formulation 

Formulating a good TMR requires many considerations. Farmers might not reap the full benefits of the TMR feeding program without good practice. For a good quality TRM feed, the following must be fulfilled. 

1. Selection of the right ingredients is vital. To prepare quality feed, choosing the best ingredients is always advisable. The fodder crop should be in the right stage. This will give a perfect amount of DM and other nutrients. 
2. The feed should have properly chopped fodder to enhance maximum benefits to animals. Fodder cutting should not be too small or too large for best utilization. Also, the roughage should be between 30-40% for lactating cows. 
3. Balancing ingredients is paramount. For feed to achieve high productivity, components must be formulated to ensure cows get balanced feed. This guarantees high production and excellent herd health. It's always ideal to analyze feed frequently in the laboratory to maintain quality. 

TRM Ingredients: How to Formulate a Super TMR Mix

Many ingredients can be used to formulate TMR. A farmer can prepare their feed if the available ingredients provide the required nutrients. The critical bit is to look for components that can supply roughage, proteins, energy and other essential nutrients. 

The most common ingredients used in TMR feeding are summarized in the table below. 

Table 1.3: Different ingredients for TMR formulation (Sources 1 & 2)

TMR Formulation for Different Groups of Dairy Cows 

Formulating TMR feed for lactating cows should be based on milk production and body weight. Also, a farmer should consider the age of an animal when formulating the ration. 

The feed is usually mixed with roughages, concentrates, and mineral supplements. Specifically, when formulating TMR for lactating cows, special care should apply to ensure animal production is at maximum without compromising health. 

A cow should consume at least 2.5%-4.5% DM of its body weight. However, during the lactation period, the DM content can be adjusted. Since DMI is reduced when cow calves, it normalizes in the 8th-10th week. Formulating feed for early lactating cows should maintain the standard requirement of DM. However, for every extra 2 liters of milk, the farmer should add a kilo of DM. 

During the mid-lactating period, cows should be encouraged to consume as much DM as possible. This ensures maximum milk production. The DM should be maintained at a minimum of 4% of body weight, while concentrates should be below 2.3% of body weight. 

When formulating TMR for late lactation cows, ration can contain standard components since milk production is in decline. The standard TMR feed will cater for the developing fetus, general animal maintenance, and milk production. 

During the dry period, the animal is not producing milk. Thus, there should be no addition of extra DM or concentration. Basing the feed on body weight, it ensures proper cow and fetus nourishment and energy for the following early lactation phase. 

The table below summarizes how to formulate TMR for lactating and dry cattle. The formulation is based on a 600 kg animal producing 40 kg, 30 kg, and 20 kg milk in early, mid, and late lactation periods. 

 Table 1.4: Nutrients requirements for dairy cows during various lactation periods (Sources 1 & 2).

Conclusion 

TMR is a perfect way to ensure precise feed delivery while minimizing waste. It’s also an excellent option for farmers to utilize locally available fodder and other materials. Allowing farmers to compensate and adjust nutrients, it's possible to maintain lactating cattle producing maximally.