BALANCED RATIONS FORMULATION OF DAIRY CATTLE IN INDIA

September 17, 2020

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BALANCED RATIONS FORMULATION OF DAIRY CATTLE IN INDIA

Dr.Devendra Singh Meratia,RAJUVAS.

Inadequate nutrition is a major cause of low live-weight gains, infertility and low milk yields in dairy cattle. About 55-70 % of cost of dairy production is made up of cost of feeds. It is important to use the available feeds in a diet that meets the needs of the cattle in the different stages of production.

Good dairy cattle feeding practices can be implemented with due regard to different nutrient requirements for the various classes of dairy stock in order to avoid either overfeeding or underfeeding of the dairy cattle and hence wastage of scarce feed resources. Balanced dairy cattle rations can be formulated using various methods, A simple calculation of the main ingredients and estimating the minerals and vitamins content or more accurate calculations using different models for reliable rations. For smallholder farmers the sophisticated method will not be applicable because of lack of reliable chemical composition of the feed and complicated calculations. If feed specifics are available and precise rations are wanted, the assistance of the local veterinary doctor could be of help in ration calculation.

Dairy cattle feed requirements

Dairy cattle feed requirements depend very much on their weight and stage of production. Whereas most farmers do not have access to weighing scales that can weigh animals, a system has been developed whereby the weight can be determined by chest measurements using a simple measuring tape (weigh band) available everywhere. The weigh band is placed around the chest a hand’s breadth behind the front legs and not too tight.

Maximum dry matter intake

Animal feedstuff can be divided into two major components namely dry matter and water. The dry matter component consists of organic and inorganic matter. The organic matter consists of carbohydrates (source of energy), lipids and fats (source of energy), protein and vitamins. The inorganic matter is the source of macro- and micro-minerals. Since all nutrients are contained in the dry matter the animal must consume this portion in adequate amounts to obtain the required nutrients.

With feeds low in energy there is a risk that the intake capacity of the animals is too small to consume enough nutrients to meet the requirements for maintenance and production. Low energy feeds might be feeds with high moisture content (low dry matter) or feeds with high fibre content (low energy) or a combination. The maximum dry mater intake is about 3 – 3.5% of a cows live weight and can be estimated with the formula kg Dry mater/cow/day = 0.025live-weight + 0.1kg milk.

Table 5 shows the maximum dry matter intake by dairy cattle of various live-weights. The intake capacity increases with live-weight and milk production (in the table kg milk standardized at 4% butterfat).

Cow live-weight (kg)
Milk yield
(4% Butter-fat) 350 400 450 500 550 600
5 10.0 10.5 11.0 11.5 12.0 12.5
10 10.5 11.0 11.5 12.0 12.5 13.0
15 12.0 13.0 13.5 14.0 14.5 15.5
20 13.5 14.5 15.5 16.0 17.0 17.5
25 15.0 16.0 17.0 17.5 18.5 19.5
30 16.5 17.5 19.0 19.5 20.5 21.0

Nutrient requirements for maintenance and milk production

The nutrient requirements for maintenance of animals are influenced by their live-weight, activity (e.g. walking long distance) and environmental temperature (too cold or too hot). Table 6 shows nutrient requirements for maintenance of dairy cattle of various live-weights (NRC, 1988. Dairying in KwaZulu-Natal, 1995 ). Dry matter intake is calculated with Fuentes-Pila (2003) and NRC (2001).

Table 6: Daily nutrient requirements for a dairy cow of a certain live weight and a certain milk production

Nutrient requirements for growth of young stock

The amount of nutrients required by an animal is equal to the nutrients in the tissue gained. Nutrients concentrations in deposited tissue are influenced by the animal rate of weight gain and the stage of growth or live-weight. The nutrients required for growth by dairy cattle of various live-weights are given in Table 7 (NRC, 2001).

Table 7. Daily nutrient requirements for growth of young stock of dairy cattle

Nutrient requirements for milk production

When feeding a dairy cow the aim should be to maximize milk yield by meeting cow’s feed requirements. Requirements for milk production will depend on the amount of milk produced by the cow, energy content of milk which is indicated by fat content (the higher the fat content the higher the energy required).

Table 8: Nutrient requirements for production of 1 kg of milk of various butter fat contents
Milk fat (%) ME Energy
(MJ) Crude protein
(g) Calcium
(g) Phosphorus
(g)
3.0 4.5 78 2.7 1.7
3.5 4.8 84 3.0 1.8
4.0 5.2 90 3.2 2.0
4.5 5.5 96 3.5 2.1
5.0 5.9 101 3.7 2.3
5.5 6.2 107 3.9 2.4

In addition to nutrient requirements for milk production nutrients will also be required to cater for other functions such as reproduction (pregnant cows require more to cater for growth of calf) and growth rate if she is not mature (in case of first calf cows).

Table 1 shows that the energy required for the production of 1 kg of milk can be met by amongst others 1 kg of dry matter of coffee hulls, napier grass early bloom, star grass or straw of rice, barley or wheat.

Mineral, trace-element and vitamin requirements for cattle

When available from feed analyses or from average feed composition, the amount of minerals, trace-elements and vitamins in a ration can also be calculated and compared with the animal requirements (as shown in table 9).

Table 9. Requirements of minerals, trace-elements and main vitamins for different categories of cattle.

As mentioned before, in generally rations with roughages for cattle will be low in copper, selenium and cobalt.

Proportions of basal diet and supplement in a dairy cow ration

The cheapest feed for milk production is good quality roughage. However, quality of roughage fed to dairy cattle is usually low resulting in sub-optimal levels of production. Further increase in production can therefore be achieved by the use of supplements. Among the factors influencing the quantities of roughage and supplements offered are their quality and level of production of dairy cattle. Table 10 shows simple guidelines on proportions of basal diet and supplements depending on levels of milk production in dairy cattle.

Table 10: Proportion of basal diet and supplements in dairy cattle rations

Milk yield (kg/day) Basal diet DM (%) Supplement DM (%)
10-14 70 30
15-19 60 40
20-24 50 50
25 and more 40 60

Ration formulation guidelines————————–

The feeds in rations fed to dairy cattle either originate from the farm or are purchased. In order to minimize feed wastage and to overcome the problem of low levels of production, feeds need to be efficiently utilized by the animal. A cow fed on balanced ration will utilize the feed more efficiently and hence it production will be better than a cow fed on imbalanced rations. Feed rations that are offered to dairy cows are considered balanced if they provide adequate nutrients (Carbohydrates, protein and minerals) to meet the animal requirements for maintenance, reproduction, growth and milk production.

For ration calculation the composition of the feed must be available and the requirements of the animal must be known. The composition of the farms own feed will not be available from all separate feeds. Tables1 and 2 above give an overview of the composition of feedstuffs used in Kenya: the values can be used in ration calculations. In table 6 the mean requirements for dairy cattle are mentioned as a guideline: in different weather conditions and for instance in diseased animals requirements can be slightly different.

Dairy farmers often remained confused while formulating ration for dairy animals. It is important to feed balanced ration to dairy animals as feed contribute a major part of the cost of production.

Benefits of scientific animal feeding———

Animal get almost exactly as per its body and production need
Due to balanced feeding farmer gets optimum production
It prevents wasteful expenditure
Improves immunity and make animals healthy
Reduces chances of infertility and improves reproductive efficiency
Variety of feed ingredients can be utilized

For scientific ration formulation, we need the following information

Animal weight
Production
Age
State of pregnancy
Last calving date
Feed available

All the information is easy to collect except animal weight but first of all we need to know weight without that we cannot calculate exact ration

Formulation of rations using a simple procedure- method—01

The simple procedure to calculate rations is chosen so that all farmers are able to calculate their own dairy rations. Using average composition data in this simple calculation gives a good idea where the ration needs compensation.

If the following information is provided:
• A cow weighing 450 kg and producing 20 kg/day of milk (4 % butter fat)
• Feeds available:

Napier grass, young: 7.9 Mj ME and 98 gram CP per kg DM
dairy meal: 9.1 Mj ME and 156 gram CP per kg DM
Maclick super:

How much of the Napier, dairy meal and minerals will meet the cows requirements.

STEP 1
From table 5 estimate maximum dry matter intake for a 450 kg cow producing 20 kg of milk (4 % butter fat) = 17 kg. The cow needs 161 Mj ME and 1826 g crude protein (and 75 g Calcium and 59 g Phosphor).

STEP 1a. Calculate whether it is possible to feed the cow with napier grass as the sole feed. Divide the ME requirement of the cow by the ME content of the napier grass: 161 / 7.9 = 20.4 kg DM of napier grass. That is far more than the maximum dry matter intake capacity of the cow. That shows that with napier grass as sole feed the cow cannot eat enough to produce 20 kg of milk. STEP 2
From table 6 estimate proportions of Napier and dairy meal for a cow producing 20 kg/ day of milk Napier grass = 17*50/100 = 8.5 kg DM and the other half of the ration is Dairy meal = also 8.5 kg DM.

STEP 3
From tables 1 and 2 estimate nutrients supplied by the feedstuffs and from table 6 estimate nutrient requirements by a 450 kg cow producing 20 kg/ day of milk (4 % butter fat)

Nutrients supplied by feeds and requirements to produce 20 kg/day of milk

There is a shortage of 16.5 Mj ME and a surplus of protein. According to table 811 does the energy shortage correspond with 3 kg of milk. To close the gap to 20 kg of milk, the cow needs more energy rich feed while the protein content can be lower; for example cassava peels. By replacing 3 kg of dairy meal by cassava peels, energy and protein get more in balance with the requirements of the cow. Whether the dairy meal will be replaced by an energy rich feed depends on the price of the feed stuffs and the price of the extra milk produced.

STEP 4
Estimate the amount of feed to be fed to the cow per day. The ration contains 8.5 kg of dry matter from Napier grass. Fresh Napier grass has a dry matter content of 20%, or 200 g/kg. The cow should be fed 8.5*1000/200 = 42.5 kg fresh Napier grass. If 5 % of the grass is wasted (not eaten by the cow) she should be provided with 42.5 *1.05) = 45 kg of fresh Napier grass. Dairy meal with a dry matter content of 90% has to be provided 8.5 *1.10 = 9.3 kg. Calcium and phosphor are sufficient.

Formulation of rations using a simple procedure- method—02

Let us take an example of cow giving 12 litres of milk

Step 1 – Weight of animal comes 400Kg
Step 2 – thumb rule of ration balancing says that 400kg cow needs 10kg dry matter (2.5% of body weight)
Step 3 – second thumb rule says divide feed ingredients into roughage (fibre which includes green fodder and straw) and concentrate (which include grains, oil cakes etc.), Animal need 2/3rd fibre and 1/3rd concentrate.
Step 4 – this animal need 6.6kg fibre/roughage and 3.3kg concentrate feed.
Step 5 – fibre is divided in the ratio of 1:2 as green fodder and straw – 2.2Kg Green and 4.4Kg Straw
Step 6 – Green fodder contains 75% moisture, so to get 2.2Kg green dry matter we must take 8.8Kg Green, similarly straw contains 10% moisture, so straw must take around 4.88Kg
Step 7 – Concentrate feeding is done as per production for every litre of milk 300g concentrate is required, in this case, 3.6Kg concentrate would be given. Dry Matter in conc. Is 90% so nearly 4Kg conc. Must be given to sustain production

Total ration required in a day = 8.8Kg Green + 4.88Kg Straw + 4Kg = 17.68Kg feed must be given

Almost all ration are deficient in macro and micro minerals so calcium must be given in the form of feed grade DCP (not liquid calcium) and good quality mineral mixture.

If animal is in young and growing stage than 15% ration must be given extra (over calculation on weight basis)
If animal is in pregnancy 10% ration must be given extra in last trimester