Development of Microbial Fermented Feed and Its Effect on the Production Performance of Holstein Cows

Yuping YAN Junguo LI Guosheng XIN Jianming RUAN Li LI Jianning DING Ning�餫n MEI Zixin LIU

Abstract [Objectives] This study was conducted to investigate the development method of microbial fermented feed and its effect on the production performance of Holstein cows.

[Methods] Thirty Holstein cows were selected and randomly divided into 2 groups， 15 cows in each group. The diet composition of the experimental group was： concentrate supplement added with 30% microbial fermented feed+silage+alfalfa hay， and the diet composition of the control group was： concentrate supplement added with 30% flax cake+silage+alfalfa hay. The experimental period was 60 d.

[Results] Compared with the control group， the experimental group increased the average daily milk yield per cow by 2.25% （P>0.05） and the total increase in average milk yield per cow in the experimental period by 43.51% （P<0.01）， and reduced the average feed-to-milk ratio by 9.20% （P<0.05）. The average gross profit per cow of the experimental group was 40.34 yuan higher than that of the control group， showing an increase of 3.53% in the economic benefit.

[Conclusions] Feeding a diet supplemented with the microbial fermented feed could improve the efficiency of Holstein cow farming and is recommended to be promoted.

Key words Microbial fermented feed; Holstein cows; Growth performance; Effect

Feeding microbial fermentation engineering technology and products have unparalleled advantages and huge development potential in solving the problems in the dairy farming industry.  It is the current research focus and development direction at home and abroad. Through the application of microbial fermentation technology and new products， new technologies and new processes of enzyme preparations， it is combined with feed production enterprises and dairy farms to form a healthy dairy farming system organism[1]. The development of microbial fermented feed can effectively use the waste residue， waste liquid and waste of the farm and sideline product processing industry， which not only produces high-quality feed for dairy cows， but also greatly reduces environmental pollution and achieves the purpose of turning waste into treasure. Feed products processed by microbial fermentation， which has greatly increased the protein content or transform the toxicity of the original substrate， is more suitable for feeding， and contains not only fats， crude protein， minerals， vitamins， and a variety of high-energy nutrient substances that can be used by cows， as well as active and inactive beneficial microorganisms， which improve the gastrointestinal microbial environment of feeding cows and the animals immunity and disease resistance[2]. The experimental results of Zhao et al.[3] showed that the average daily milk yield of each lactating cow in the experimental group fed with amino acid starter-fermented feed during the experiment was higher than the control group by 11.4% （P<0.01）. Wang et al.[4] showed that the use of fermented feed for dairy cows can improve the appetite of dairy cows， increase the dry matter intake of dairy cows， and significantly improve the digestion and absorption of nutrients.

This project adopted a new process of yeast and enzyme preparation mixed fermentation， during which carbohydrates such as sugar， fiber， organic acid， pectin and so on contained in vegetable residues （stalks and leaves of day lily， potato shoots， watermelon shoots， cabbage）， potato residue， grape seed residue， cottonseed meal， rapeseed meal， rice bran and other cheap or nutrient-containing substrates were converted into harmless protein feed by microbial fermentation[5-6]， through which large molecular substances that are difficult to digest and absorb were degraded depending on microbes and enzymes into small molecular nutrients that can be absorbed and utilized. The microbial fermented feed was fed to dairy cows to verify the feasibility and practical benefits of the research results.

Materials and Methods

Fermentation substrate

The fermentation substrate contained vegetable residues at 10%， potato residue at 10%， grape seed residue at 10%， brewers grains at 25%， cottonseed meal at 25%， rapeseed meal at 10% and rice bran at 10%.

Fermentation treatment

Microbial selection

The microbial agent composition and corresponding addition amounts were as follows： dry yeast 0.50%， cellulase 0.01%， protease 0.01%， lipase 0.01%， α-galactosidase 0.01%， β-mannanase 0.01% and glucose oxidase 0.01 %.

Ingredients for the microbial fermented feed

The ingredients for the microbial fermented feed and corresponding addition amounts were as follows： fermentation substrate 95.0%， ammonium sulfate 2.5%， magnesium sulfate 1.0%， potassium dihydrogen phosphate 0.5% and urea 1.0%.

Fermentation process for the microbial fermented feed

After the raw materials were accurately weighed， mixed and put into a constant-pressure steamer. During steaming， the temperature was kept at 120 ℃ for 30 min. When the steam temperature dropped to 38- 45 ℃， the spare compound microbial agent was inoculated and mixed with the steamed material. Fermentation was performed in a fermentor at a temperature of 30-34 ℃ and a pH value of 6 for 24 h. The fermentation product was dried and crushed， and the product was the microbial fermented feed， which was then bagged.

Nutritional components of the microbial fermented feed

The nutritional components of the microbial fermented feed and corresponding contents were as follows： crude protein 20.15%， crude fat 4.36%， crude fiber 4.27%， crude ash 2.89%， calcium 1.02%， phosphorus 0.75% and moisture 10.23%.

Experimental design

Experimental design method

The experment adopted completely random design， and single factor tests were carried out.

Experimental animals and groups

Thirty Holstein cows with basically the same age， weight， parity， lactation month and milk production were selected and randomly divided into 2 groups， 15 cows in each group.

Diet composition and nutrition levels

The diet composition of the experimental group was： concentrate supplement added with 30% microbial fermented feed+silage+alfalfa hay， and the diet composition of the control group was： concentrate supplement added with 30% flax cake+silage+alfalfa hay. The diet composition and nutrition level are shown in Table 1.

Experimental period

The experimental period was 60 d.

Daily management of feeding test

All the test cows were tethered in standardized double-row sheds， and raised under the same feeding management conditions. They were fed 3 times a day， with coarse material first and then concentrate. The body and breasts of the cows were cleaned and milked twice. The cows were fed waterfreely， and exercised freely.

Observation index

The milk-fat percentage was tested on the day of the start of the experiment and the end of the experiment. The milk yield was recorded every day， and the total increase in milk yield per cow， feed intake and feed-to-milk ratio were calculated.

Data analysis

The experimental data was statistically analyzed by multiple comparisons.

Results and Analysis

Experimental observation

There were no obvious changes in the experimental group and the control group. The feces， hair color and mental state were in good condition， and there were no clinical symptoms. The initial weight and final weight of the tested cows were determined， and the results are shown in Table 2.

It could be seen from the results in Table 2 that the total increase in average milk yield per cow during the experimental period was 43.51% higher in the experimental group than in the control group， and the difference was extremely significant. The feed-to-milk ratio was 9.20% lower than that of the control group， with a significant difference.

Economic benefit analysis

Table 3 shows the economic benefit analysis. The analysis showed that the gross profit of the experimental group was 1 183.39 yuan， higher than the control group （1 143.05 yuan） by 40.34 yuan， with an increase of 3.53%.

Conclusions and Discussion

The microbial fermented feed had no adverse effects on the growth of Holstein cows. The experimental observation showed that there were no significant changes in the experimental group and the control group. The feces， hair color and mental state were in good condition， and there were no clinical symptoms.

Feeding Holstein cows with diets supplemented with the microbial fermented feed increased the milk yield of the test cows. The average daily milk yield per cow increased by 2.25% （P>0.05）， and the total increase in average milk yield per cow in the experimental period increased by 43.51% （P<0.01）. It could increase the feed reward of dairy cows diet and reduce the cost of feed. The average feed-to-milk ratio was reduced by 9.20% （P<0.05）.

The gross weight gain of the test group was 40.34 yuan higher than that of the control group， showing an increase of 3.53%. It suggests that feeding diets with the microbial fermented feed could improve the efficiency of Holstein cow farming.

References

[1] ZHANG JY， HUO GM， ZHANG LY. Development status and prospect of microbial fermented feed[J]. Journal of Nanjing Xiaozhuang University， 2009（3）： 68-71. （in Chinese）

[2] WANG Y. The mechanism of microbial fermented feed[J]. Henan Science & Technology， 2013（10）： 193. （in Chinese）

[3] ZHAO H， ZHANG L， ZHANG N. Experiment of feeding lactating cows with amino acid starter-fermented feed[J]. Xinjiang Xu Mu Ye， 2009（1）： 27-28. （in Chinese）

[4] WANG SJ， WANG XJ， JI DF. Experiments on feeding milk to lactating cows with microbial fermented feed[J]. China Dairy Cattle， 2004（3）： 27-29. （in Chinese）

[5] FENG XW， XU GS， LANG SL. Analysis of nutritional components of fermented grape residue and evaluation of feed value[J]. Heilongjiang Animal Science and Veterinary Medicine， 2012（9）： 82-83. （in Chinese）

[6] TAN JM， SHI QY. Study on the production of mycoprotein feed by solid fermentation of potato residue[J]. Journal of Microbiology， 1999， 19（6）： 23-27. （in Chinese）

[7] FENG L， ZHANG WJ， YU L， et al. Optimization of fermentation process parameters of cotton meal-derived bioprotein feed[J]. Heilongjiang Animal Science and Veterinary Medicine， 2011（4）： 86-88. （in Chinese）