Try this link - http://www.uni-kiel.de/marktlehre/presse/feed.pdf or file below.

It describes two common German estimations for energy and contains a formula for ME calculation.

Thanks very much. I have also find this ressource on scholar.

Respectable prof Awohouedji Doha Yetongnon G

I would like to share with you one paper, that I m using sometimes when I need to calculate feed nutrients of lactating cows ..........if you dont have in your library, please read it carefully ........we use some Yugoslavian standards in our country Republic of Macedonia, but I dont know how to explain you the calculation :)

I hope that I will be productive for you

Best, Vesna

Thanks very much. it'll be useful...

Hello!

I have one idea, please check this document, it is helpful....for my PhD experiment was examined the urea level (blood and milk) and total proteins and glucose at dairy cows to check protein- energy status (I was interested for metabolism).....please see this formulas ......nice evening

Thanks...

it is very simple , after predict of DE you can calculate ME with this formola:

ME= DE*0/82

Could you share the paper or the reference of this formula?

Kind regards

you can find this formola in chapter 10 ( energy metabolism) book " basic animal nutrition and feeding 5th ed" Pond and Church.

for 3x feeding level Me(mcal/kg)= 1.01DE (mcal/kg)-0.45 NRC 2000

also you can predict DE1x by this formola:

(tdNFC/100)*4.2+(td CP/100) *5.6+(FA/100)*9.4-0.3 NRC2000

FA=EE-1

Thanks

 ME can be determine using the formula; %ME = 36 * CP% + 81.8 * EE% +35.5 * NFE%. Reference; Pauzenga, U. (1985). Feeding Parent Stock. Zootecnica internation. Pp. 22-24. organic matter can be determine as a difference between dry matter and ash. NDF and ADF can determine as described by VanSoest et al. (1991) method. Reference to Van Soest, P.S., Robertson, J.B. and Lewis, B.A. (1991). Methods of Dietary Fiber, Neutral Detergent Fiber and Non-Starch Polysaccharides in Relation to Animal Nutrition. J. of Dairy Sci., 74: 3583-3597

Chapter 3. Determination of the feedstuffs energy and protein value in the ruminant nutrition

Table of Contents

The energy value of feeds in ruminants nutrition

The net energy for milk production (NEl)

The energy value of feed in the nutrition of growing and beef cattle

The protein value of feeds in ruminants nutrition

The energy value of feeds in ruminants nutrition

When calculating the daily ration, the starting point should be to cover the energy requirement of animals. For this purpose the net energy content of feeds shall be used for ruminants. It is because, in contrast to the monogastric animals, there is only a weak correlation between the digestible (DE), or metabolizable (ME) energy and the net (NE) energy content of the feeds in ruminants. This follows from the heterogeneous feed ration of ruminants, namely, in contrast to monogastric animals, they consume significant amount of roughages besides concentrates. The roughages have very different chemical composition, varying heat production (thermic energy) and the amount of methane produced in the rumen. For these reasons the energy requirement can only be met with sufficient accuracy in ruminants if the net energy of the feed is taken into account instead of digestible (DE) or metabolizable (ME) energy.

Instead of the nearly 100 years used starch equivalent value, due of its flaws and inaccuracies, the partial net energy system was introduced in the nutrition of ruminants in Hungary - similarly to the other countries in the world - in 1986. Several research results in USA and in Western-Europe justified the development and implementation of the new partial net energy system. These are the followings:

The efficiency of the utilization of feed metabolizable energy (‘k factor’) is significantly influenced by the functions (maintenance, milk, meat, or fat production). Feeding natural feeds, it is the most efficient (70-75%) when the ME is used for maintenance. Lower efficiency is found in the case of weight gain, however the efficiency of utilization also depends on its composition (protein and fat content). It is worse in the synthesis of protein (35-50 %) and is improved in the synthesis of fat (60-70 %).The mean efficiency of utilization of ME for milk production is 63%.

The efficiency of utilization of ME is also influenced by the metabolizability of feed energy, it is the metabolizable energy divided by the gross energy (q factor). This factor has the largest impact on the energy utilization (‘k’ factor) in case of growing and fattening, while this effect is similar and smaller in case of maintenance and milk production than that of fattening (Figure 5.).

The feeding level (I = the ratio between the metabolizable energy intake and the amount of metabolizable energy used for maintenance (ME/ME maintenance) affect the rate of passage and the digestibility of the nutrients and thereby the ME content of the feeds.

The ME of feed is utilised with similar efficiency for both milk production and weight gain in lactating dairy cows, which allows the expression of the energy requirement in net energy lactation (NElactation) for both type of production.

The net energy for milk production (NEl)

The net energy system of milk production, developed by Moe et al., and introduced in the USA in 1969, was adopted in Hungary. The decision was motivated that the system has been developed on the basis of a large number of experimental results (hundreds of respiration experiment data). In addition, the system takes into account the results which were summarized earlier.

When we adopted the equation determining the net energy for milk production of feeds, we were having regard to the finding of Van Soest at al.(1979), that the impact of the feeding level on nutrient digestibility may not be the same for all feed, because it depends on the fibre content and the fibre composition. Moe at al. (1976) calculated initially 4% decrease in the digestibility when the feeding level increased with one unit. In contrast, Van Soest at al. proposed to take into account the effect of feeding level with different discount factor, depending on the feedstuffs. On this basis the net energy for milk production at three times maintenance level is calculated with the next formula:

NEl (MJ/kg DM) = 0,6032 • DE• (1-2•df)-0,502

(DE = digestible energy (MJ/kg DM), df = discount factor)

Respiratory experiments have shown that the cows recovered 63 % efficiency the metabolisable energy of feed for milk production. This is considered a good efficiency of the transformation, if we also regard that a significant proportion of the cow energy requirement is covered with roughages having less energy concentration than concentrates.

The utilization of ME for milk production also depends on the condition of cows. In a feeding period of energy shortages, which often occurs in the first trimester of lactation, the cows utilize fat reserves to compensate the missing energy. In such a case the energy utilization is very high, reaching 84 %. 1 kg body weight loss is equivalent to 20.61 MJ NEl, which cover the energy requirement of 6.6 litre FCM milk.

When the cows condition improves (in the last trimester of lactation), the energy used for weight gain reduces the amount of energy available for milk production. Since the metabolizable energy utilisation efficiency for weight gain is only 60%, 1 kg weight gain reduces the amount of energy available for milk production by 26.77 MJ NEl.

The energy value of feed in the nutrition of growing and beef cattle

The energy requirements for maintenance and weight gain can not be expressed in the same energy unit (maintenance or net energy for growth) in the nutrition of growing and beef cattle. One reason for this is that the varying metabolizability of feeds has very different impact on the efficiency of utilization of the metabolizable energy (‘k’ factor), and among the reasons it should be also mentioned that the ‘k’ factor is significantly different for maintenance or weight gain. Similarly to the dairy cows, the net energy system, developed in the USA by Lofgreen and Garett (1963) for beef cattle has been introduced to replace starch equivalent value. It must be noted, that the system is based on a large number of experiments using comparative slaughter technique and carcass composition.

The net energy for maintenance (NEm)

The maintenance net energy requirement of animals is equal to the amount of energy required for maintaining energy balance. When the maintenance net energy content of a feed is evaluated, essentially the quantity of feed necessary for maintaining the energy balance of a metabolic weight unit (W0.75) is determined. Knowing this value, as well as the maintenance energy requirement of a unit metabolic weight (W0.75), the maintenance net energy content of feeds (NEm) can be calculated. On this basis, the NEm content of a feed is equal to the heat loss, that the amount of feed per unit is able to compensate in the body. Based on the results of a large number of feeding experiments of significantly different forage:concentrate ratio, Lofgreen and Garrett found the next correlation between the net energy for maintenance and metabolizable energy content of feeds:

NEm (MJ/kg dry matter)=1.37•ME-0.033•ME2+0.0006•ME3-4.684

ME (MJ/kg dry matter)= 0.82•DE

The net energy for weight gain (NEg)

From the concept of net energy follows, that the net energy for gain (NEg) content of a feed is equivalent to the energy content of weight gain, which results in the feeding of one unit feed. NEg is determined by the so called ‘differential experiment’. The feed in question is fed in two different amounts and the energy of the induced growth is measured.

Lofgreen and Garrett conducted a lot of differential trials and found the next relationship between the net energy for gain and the metabolizable energy content of feeds:

NEg (MJ/ kg dry matter) = 1.42•ME-0.0416•ME2+0.0007•ME3-6.904

https://scholarworks.uark.edu/cgi/viewcontent.cgi?article=4639&context=etd