Guinea pigs are monogastric herbivorous animals. They have sharp teeth, well-developed chewing muscles and an extra-large cecum containing a large number of beneficial microorganisms. Guinea pigs have a high digestion and utilization rate of crude fiber. The United States (NRC1997) announced that guinea pigs have a high digestion and utilization rate of crude fiber. The digestibility of cattle is 33% respectively, second only to cattle (44%) and horses (41%). "GB14924.3-2010 Nutrient Composition of Compound Feeds for Laboratory Animals" requires that the crude fiber content in guinea pig diets should account for 10%-15% to meet the metabolic needs of guinea pigs for growth and development. If the guinea pig concentrate lacks crude fiber, the guinea pig's teeth will overgrow, which will also lead to digestive disorders and related diseases.

This article discusses the digestion and utilization of crude fiber by guinea pigs and the effects of different fiber levels on the growth of guinea pigs. Developmental influences are outlined.

Digestion and absorption characteristics of crude fiber in guinea pigs

The physiological structure of the guinea pig determines its efficient digestion and utilization of fiber. Its masseter muscles are well developed, and there are two spots at the back of the mouth near the cheeks. There are 8 molars in the upper and lower teeth, which can fully chew food.

In addition to strong chewing ability, guinea pigs also have a huge thin-walled pouch-like well-developed cecum, which is pulled by three colonic bands to form many side pouches. It is about 15~20cm long and can accommodate about Comprising 65% of the gastrointestinal tract contents, the fermentation capacity of the guinea pig cecum is 2.5 times that of the rat colon and contains similar concentrations of short-chain fatty acids as those in the cow rumen.

After being eaten by guinea pigs, fiber-rich food quickly passes through the stomach and small intestine, and is broken down into digestible fiber and indigestible fiber in the intestine. After the indigestible fiber enters the enlarged cecum, it is absorbed in the cecum. Under the fermentation of a large number of beneficial bacteria, crude fiber is decomposed into digestible crude fiber, which is then excreted in the feces.

Guinea pigs have coprophagia. By eating feces, they reabsorb and utilize some amino acids and B group microorganisms synthesized by the microbial flora in the back end of the intestine.

The impact of crude fiber on guinea pig dental health

Like other rodents, guinea pigs’ teeth will continue to grow throughout their lives, so they need to eat foods with high fiber content regularly. Prevents tooth overgrowth. If there is insufficient fiber intake in the diet and insufficient tooth wear, severe dental malocclusion may occur, resulting in an inability to eat and hunger. Therefore, the diet should be mainly timothy grass or hay, and can be fed ad libitum.

Different crude fiber qualities have different effects on the degree of tooth wear of guinea pigs. When fed an all-hay diet, there was a significant effect on the tooth length of the upper incisors and cheek teeth of guinea pigs, but no significant effect on the lower incisors and cheek teeth, and only on the wear and growth of the lower incisors. In the crude fiber feed composed of rice husk and sand, the upper cheek teeth wear the most, and the impact of abrasive on the upper cheek teeth is greater than that of the lower cheek teeth.

The importance of crude fiber to the intestinal health of guinea pigs

Crude fiber is called the six major nutrients after carbohydrates, crude fat, crude protein, vitamins, water and inorganic salts. As the seventh largest nutrient, the importance of crude fiber to guinea pig intestinal health is reflected in assisting digestion, promoting intestinal growth and development, and maintaining intestinal microecological balance.

1. Crude fiber aids digestion

Fiber can handle food waste and is the best food waste cleaner in the body and intestines. It has a good ability to aid digestion and excretion of solid waste. effect.

Crude fiber, with its larger particles and rough surface, stimulates gastrointestinal peristalsis through mechanical action, accelerates the migration of chyme to the rear end, avoids digestive disorders caused by food retention and fermentation, and has the effect of moisturizing the intestines. Laxative effect. At the same time, dietary fiber can also reduce the proliferation of pathogens in the small intestine, stimulate blood circulation in the intestinal mucosa, and promote full intestinal development.

2. Crude fiber balances intestinal microecology

Intestinal microecological balance can effectively promote the growth, development and health of animals. The crude fiber in the guinea pig diet that cannot be digested and decomposed is often used as a substrate for cecal microbial fermentation. The fermentation level of crude fiber is one of the important factors in maintaining the balance of intestinal microecology. Volatile fatty acids produced during fermentation, such as butyl Organic acids such as acid, propionic acid, acetic acid and lactic acid can reduce intestinal pH, inhibit the growth of harmful bacteria such as Clostridium and Escherichia coli, and promote the growth and reproduction of beneficial microorganisms, thereby improving the intestinal microecological balance and maintaining intestinal Tao health.

If high-starch, low-level fiber diets are fed for a long time, pathogenic aerobacteria will multiply in the cecum of guinea pigs, causing cecal flatulence to expand, leading to an imbalance of bacterial flora, and causing diarrhea in guinea pigs. Guinea pigs fed a purified diet showed improved growth performance and reduced salmonella levels when consuming a diet rich in plant fiber.

The impact of crude fiber on the growth performance of guinea pigs

1. The impact of different levels of crude fiber on the growth performance of guinea pigs

Booth et al. first observed that feeding Guinea pigs fed a synthetic diet without crude fiber had a lower growth rate (1.9 g/day). Adding pectin, natural gum arabic, oat straw, cellulose and cellophane promoted the growth of guinea pigs to a certain extent, but it was found that natural gum arabic produced the best growth-promoting effect (growth rate exceeded 5 g/day). Later, it was discovered that adding 150g/kg of cellulose to the guinea pig diet can more effectively stimulate the growth and development of guinea pigs.

In terms of pig nutrition, when the proportion of alfalfa in the diet increases to 20%, 40% and 60%, the feed intake and average body weight gain of pigs decrease with the increase in crude fiber level. When crude fiber is used to replace 50% of grain concentrate, the feed intake or body weight of guinea pigs does not change significantly, indicating that guinea pigs are more tolerant of rough feeding than pigs and can effectively use crude fiber as an energy resource. However, when the proportion of crude fiber in the basic diet was 50%-75%, the feed intake of guinea pigs increased linearly, but the body weight gain did not change significantly. This is mainly because increasing the level of crude fiber will increase the burden on the digestive tract and increase the concentration of volatile fatty acids such as acetic acid and butyric acid in the cecum. The increased concentration of butyric acid increases intestinal excitability and accelerates peristalsis, resulting in a short residence time of food in the cecum, low digestibility of nutrients, and low effectiveness.

2. Effects of crude fiber from different sources on the growth performance of guinea pigs

Guinea pigs like young grasses or dry forages with more cellulose, but fresh grasses have more water. It is not convenient to add directly to the production of compound feed, and it is not convenient to store in the feed factory. Therefore, alfalfa, timothy grass, bran, elephant grass and other grass powder or hay are usually added to compound feed to meet the growth and development and daily metabolism requirements of guinea pigs. Required crude fiber.

Although alfalfa is a leguminous herbaceous plant, it has the same high fiber and low protein characteristics as timothy grass and elephant grass. It is very suitable as the main grass for guinea pigs and can promote the growth and development of guinea pigs. effect. Both dried alfalfa and washed alfalfa pulp had significant growth-promoting activity in guinea pigs. Calloway et al. reported that alfalfa meal supplementation could reduce mortality in SPF experimental guinea pigs. Reid and Mickelsen also confirmed that adding dry alfalfa to guinea pig semi-purified feed can promote the growth of guinea pigs.

In addition to pasture, processed agricultural and sideline products such as bran and sugar beet pulp are also considered to be crude fiber raw materials that are beneficial to the growth of guinea pigs. Bran is a crude fiber raw material with rich resources and low price. It is a by-product of the processing of rice, wheat and other cereal grains and belongs to the bran category. Its crude protein content is low, about 5%, and its crude fiber content can be as high as 31%-35%. Although the crude fiber of bran bran contains more lignin, in actual production, it is unanimously believed that adding an appropriate proportion of bran bran is necessary. Bran does not affect the growth and development of livestock, poultry, rabbits and guinea pigs.

Research has found that Tongchang bran can completely or partially replace alfalfa, and its effects on the growth and development, organ coefficients and serum biochemistry of guinea pigs are equivalent to those of alfalfa. Beet pulp contains 8% crude protein, 54% NDF and 33% ADF. Compared with other grass-based fiber sources, guinea pigs have a higher ability to digest and absorb the dry matter and crude fiber in sugar beet pulp, but The growth-promoting effect is not good. Therefore, choosing a suitable source of crude fiber is also crucial for guinea pig diets.

Summary

Add an appropriate amount of crude fiber to the guinea pig diet Fiber is essential and beneficial for overall growth and development, but too much or too little can have anti-nutritional and health-damaging effects. However, the quality and composition of crude fiber are diverse, such as the impact of acidic detergent fiber and neutral detergent on the growth and development of guinea pigs, especially on reproductive function and physiological metabolism. Research in this area is still blank.

In the future, a comprehensive analysis of the digestion, utilization and overall functions of different crude fibers in guinea pigs and determination of the specific addition level of crude fiber in guinea pig diets requires further in-depth research.