**1. Introduction**

362 Lactic Acid Bacteria – R & D for Food, Health and Livestock Purposes

(February 2002), pp.7-11, ISSN 1476-5535

ISBN 0195125797, USA

Zopollatto, M., Daniel, J.L.P. & Nussio, L.G. (2009). Aditivos microbiológicos em silagens no Brasil: revisão dos aspectos da ensilagem e do desempenho de animais. *Revista Brasileira* 

Weinberg, z.g., Ashbell, G., Hen, Y., Azrieli, A., Szakacs, G. & Filya, I. (2002). Ensiling whole-crop wheat and corn in large containers with *Lactobacillus plantarum* and *Lactobacillus buchneri. Journal of Industrial Microbiology & Biotechnology*. Vol.28, No.19,

White, D. (2000). *The physiology and biochemistry of prokaryotes* (2). Oxford University Press,

Woolford, M. K. (1984). *The silage fermentation*. Marcel Dekker, ISBN 0824770390, New York

*de Zootecnia*. Vol.38, No.spe, (February 2006), pp.170-189, ISSN 1806-9290

The utilization of whole crop rice (WCR) as an animal feed has proven economically viable, not only as a way of disposing of rice straw residues but also as a real alternative for feeding livestock in regions where rice is the main crop (Han et al., 1974). As a result, in Japan and other rice-producing countries, rice is no longer grown exclusively for human consumption but increasingly as a valuable forage crop. Forage rice is in fact believed to be an ideal alternative crop, not only in helping farmers adjust grain rice production but also in preserving the soil, leading to long-term utilization of the paddy field. Yet a major drawback of forage rice is that it yields low-quality silage, due to poor digestibility of nutrients, mostly crude proteins (Cai et al., 2003). Several processes have been developed to improve the fermentation and nutritional value of whole-crop silage from forage paddy rice. Breeding programs are carried out, and newly developed rice varieties with increased yield and amount of digestible nutrients are being grown and tested. Also, harvesting, preparation, and storage techniques are constantly being improved. However, WCR is usually insufficient in sugars and lactic acid bacteria (LAB), and may produce silages rich in ethanol rather than lactic acid and volatile fatty acid (VFA) (Cai et al., 2003). This could be attributed to the structure of the rice plant; the hollow stem may increase the air in a silo, facilitating yeast WCR is usually insufficient in sugars and lactic acid bacteria (LAB) (Cai et al., 2003), and may produce silages rich in ethanol rather than lactic acid and VFA (Yamamoto et al., 2004). This could be attributed to the structure of the rice plant; the hollow stem may increase the air in a silo, facilitating yeast growth especially in the early ensiling period. Furthermore, most of the processes used to date still rely on heavy chemical treatments with ammonia and sodium hydroxide and were reported to reduce the palatability of silage to ruminants (Cai et al., 2003; Enishi et al., 1998). Of the many factors that can affect silage fermentation, the type of microorganisms that dominate the process often dictates the final quality of the silage. For instance, homolactic fermentation by LAB is more desirable than

© 2013 Takahashi et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

other types of fermentation because the theoretical recoveries of dry matter and energy are greatest. During this type of fermentation, LAB utilizes water-soluble carbohydrates to produce lactic acid, the primary acid responsible for decreasing the pH in silage. In contrast, other fermentations are less efficient. Natural populations of LAB on plant material are often low in number and heterofermentative. Thus, the concept of using a microbial inoculant to silage involves adding fast-growing homofermentative LAB in order to dominate the fermentation, thereby producing higher-quality silage. Some of the commonly used homofermentative LAB in silage inoculants include *Lactobacillus plantarum*, *Lactobacillus acidophilus*, *Pediococcus acidilactici*, and *Enterococcus faecium*. Commercially available microbial inoculants contain one or more of these bacteria that have been selected for their ability to dominate the fermentation.

Ruminal Digestibility and Quality of Silage Conserved via Fermentation by Lactobacilli 365

use of food by-products is increasing due to economic and environmental concerns. Residues from vegetables such as white cabbage, Chinese cabbage, red cabbage, and lettuce are high in nutrients such as vitamins, minerals, and vegetable fiber, and large quantities of these vegetables are produced annually in many countries, including Japan. However, these vegetable residues perish easily because of their high moisture content. Technologies to create high-quality animal feed from vegetable residues and to provide long-term storage of the resulting silage need to be developed. In regions where vegetable residues are the main food by-product, the use of vegetable-residue silage as animal feed has proven economically viable, not only as a way of disposing of vegetable residues but also as an alternative livestock feed. To prepare fermented by-product mix as ruminant feed, it is important to

The purpose of this experiment was to examine the effects of lactic acid bacteria inoculant on the quality of fermentation and ruminal digestibility and fermentation characteristics of ruminant fed silage, and to determine the chemical and microorganism composition of vegetable residues, and the influence of lactic acid bacteria addition and moisture

Experiments were conducted with permission from the Committee of Animal Experimentation, and according to the animal care and use institutional guidelines for

Whole crop rice (Haenuki) was cultivated using transplant cultivating methods in a paddy field on an experimental farm at Yamagata University, Japan, and harvested at the full-ripe stage with a length of 2 cm. As shown in Table 1, TMR was prepared using compound feed (Kitanihon-Kumiai Feed, Yamagata, Japan), WCR, dried beet pulp, a vitamin-mineral supplement (Snow Brand Seed, Iwate, Japan), dried tofu cake (Zenno, Tsuruoka, Japan), molasses (sugarcane; Dai-Nippon Meiji Sugar Co., Tokyo, Japan) and LAB (*Lactobacillus plantarum* Chikuso-1, Snow Brand Seed, Sapporo, Japan). Experimental treatments included control silage without additive, or with molasses, (4% FM basis), LAB (5 mg kg–1 FM basis), and molasses+LAB. Moisture was adjusted with water to approximately 65%. Silages were prepared using a small-scale system of silage fermentation. Approximately 1 kg TMR was packed into plastic film bags (Hiryu BN-12 type, 270 mm × 400 mm, Asahikasei, Tokyo, Japan), and the bags were sealed with a vacuum sealer (SQ303, Sharp, Osaka, Japan). Three

adjustment on fermentation quality and the in vitro ruminal fermentability of silages.

investigate the digestive characteristics of these vegetable residues.

animal experiments at the Faculty of Agriculture, Yamagata University.

silos per treatment were prepared and stored in a room at 20–25°C for 60 days.

Residues of white cabbage (*Brassica campestris* L. *var. capitata*), Chinese cabbage (*Brassica rapa* L. *var. glabra Regel*), red cabbage (*Brassica oleracea* var. *capitata F. rubra*), and lettuce (*Lactuca sativa* L.) (three samples of each) were collected from a local commercial vegetable factory (Fujiyama factory, Matsuya Foods Company, Limited, Fujinomiya,

**2. Materials and methods** 

**2.1. Silage preparation** 

Food by-product such as tofu cake is high in crude protein and fatty acids (Xu et al. 2001). Not only could the by-products be utilized as a source of nutrients for ruminants, but using them to replace imported commercial feedstuffs could save energy in transportation, and possibly reduce the environmental impact of burning them as waste of burying them landfills. Preparing total mixed ration (TMR) silage is one practice whereby food byproducts are stored and utilized as animal feeds in Japan (Imai, 2001). Our previous study (Cao et al., 2009b) showed that TMR silage with 30% dried tofu cake had the higher lactic acid content than that with rice bran or green tea waste. Alli et al. (1984) reported that as molasses can provide fermentable sugars for the production of organic acids, it has been used extensively as a fermentation aid, and that silage prepared with molasses may show a lower pH, higher residual water-soluble carbohydrates levels, greater quantities of lactic acid, lower levels of volatile basic nitrogen, and decreased dry matter (DM) loss compared to silage without molasses. Weinberg et al. (2003) also reported a high lactic acid content in silage ensiled with straw and molasses.

However, even if there is plenty of glucose as a substrate, if insufficient in lactic acid bacteria, to preparing good quality silage is difficult. Cai et al. (1999) reported that the factors involved in fermentation quality include chemical composition, particularly the water-soluble carbohydrates content of the silage material and the physiological properties of epiphytic bacteria. Conservation of forage crops by ensiling is based on natural fermentation in which epiphytic LAB convert sugars into lactic acid under anaerobic conditions. As a result, the pH decreases and the forage is preserved. The fermentation quality of silage is influenced by the size, diversity and activity of epiphytic LAB. The population density of LAB has been reported to range from 10–103 CFU/g fresh matter (FM) on standing forage crops to 103–107 CFU/g FM on chopped ones entering the silo. Generally, When LAB reaches at least 105 (CFU/g of FM), silage can be well preserved; if LAB values below 105 high-quality silage fermentation may need to be controlled using certain inoculants. *Lactobacillus plantarum* Chikuso-1 is shown to have great potential as an inoculant for WCR silage (Cai et al., 1999, 2003; Cai, 2001; Cao et al., 2011).

Furthermore, Commercial processing of vegetables results in many residues, but most are burned and dumped into landfills or used as compost, which is a waste of resources and leads to possible environmental problems due to unsuitable disposal. Demand for efficient use of food by-products is increasing due to economic and environmental concerns. Residues from vegetables such as white cabbage, Chinese cabbage, red cabbage, and lettuce are high in nutrients such as vitamins, minerals, and vegetable fiber, and large quantities of these vegetables are produced annually in many countries, including Japan. However, these vegetable residues perish easily because of their high moisture content. Technologies to create high-quality animal feed from vegetable residues and to provide long-term storage of the resulting silage need to be developed. In regions where vegetable residues are the main food by-product, the use of vegetable-residue silage as animal feed has proven economically viable, not only as a way of disposing of vegetable residues but also as an alternative livestock feed. To prepare fermented by-product mix as ruminant feed, it is important to investigate the digestive characteristics of these vegetable residues.

The purpose of this experiment was to examine the effects of lactic acid bacteria inoculant on the quality of fermentation and ruminal digestibility and fermentation characteristics of ruminant fed silage, and to determine the chemical and microorganism composition of vegetable residues, and the influence of lactic acid bacteria addition and moisture adjustment on fermentation quality and the in vitro ruminal fermentability of silages.
