Feed Options for Ruminants in the Tropics

This article is from ECHO Asia Note # 31.

[Editor’s Note: This article marks the fourth and final installment of a series of on-farm animal feed creation articles written by Keith Mikkelson at Aloha House Orphanage and Sustainable Farm in Puerto Princesa, Philippines. Keith’s prior articles include AN #20 Fish Feed, AN #25 Hog Feed, and AN #28 Poultry Feed. These articles have shown how utilizing on-farm products for animal feed can reduce dependency on external (often costly) inputs, thereby increasing sustainability and profitability.]

Introduction

The amazing multi-stomached ruminant comes in many forms, with varied nutritional requirements. Ruminants are even-toed, cloven-hoofed, four-legged, cud-chewing mammals of the suborder Ruminantia (within order Artiodactyla). Cattle, water buffalo, goats, and yaks are some of the ruminants found in Southeast Asia. 

Ruminants are able to digest and extract nutrients from plant-based food by fermenting it in a specialized stomach with the aid of beneficial microorganisms, prior to digestion (Figure 1). After the initial fermentation, the fermented cud is regurgitated and chewed again. The process of re-chewing the cud (to further break down plant matter and to stimulate digestion) is called rumination. The waste from ruminants is valuable as a fertilizer for better production of the forage they eat. Manure should be used on the farm to maintain soil fertility. One of the benefits of integrated livestock will be better plant health and yield owing to the recycling of nutrients on the farm.

Many options are available for feeding ruminants on the small farm. Before selecting a feeding strategy for your situation, be sure that the benefits outweigh the disadvantages. Every farm is unique, and farmers must determine the most appropriate and cost-effective techniques for their needs.

Optimum Health of Ruminant Herds

Sunshine and grass are some of the best sources of nutrients for cattle and sheep, but may not provide a complete diet for other ruminants. However, all ruminants will benefit from some grassland when properly managed, perhaps integrated with other feedstocks, such as legume shrubs or even azolla. The bulk of this article will discuss two of the three topics listed above in Table 1 (hay and natural pasture). We will not be covering silage or feedlot grains except to point out in Table 2 their advantages and disadvantages and with one reference below.

Cattle

Native beef and dairy cows in Southeast Asia are hardy breeds that thrive in a variety of environments from the high Himalayan mountains to the humid tropics. Some breeds were introduced by European settlers or migratory peoples. In the Philippines, the “native” cow was actually introduced by the Spanish; they brought several varieties to their newly claimed colony over 400 years ago. Many countries have old-line breeds that have cross-bred for centuries and that have adapted to the local climate and context. We will look at beef cattle feed options first and then suggest ways to increase milk yields for a dairy herd.

Water and Mineral Salt

Water must be available throughout the day to maintain herd health. Salt (sodium chloride, NaCl) is also an essential nutrient for cattle. On average, cattle should consume 11 to 15 grams of salt per day to meet nutritional requirements. Both sodium and chloride can be consumed by cattle in relatively high amounts without negative effects, but dietary levels of NaCl should not exceed 8 percent of the daily diet by weight (Ward and Lardy 2005). In areas where imported mineral blocks are too costly, sea salt can be given as “free choice” (i.e. salt is left out and animals are free to eat as much as they need). According to Troy Smith, the sodium in salt is the only mineral about which animals exhibit “nutritional wisdom”; he says they will take only as much as needed when offered free choice, without over-consuming (2008).

We make a stabilized rammed earth salt block that is still highly experimental. It consists of various quantities of on-farm red clay sub soil, 2 to 3 kilos jagged “plastering” sand, 100 to 500 grams molasses, 100 to 200 grams Epsom Salt, and 1 kilogram hydrated lime or Portland cement with 3 kilos sea salt. We are still analyzing the performance of these blocks, but they do have some research basis  (Liu et al. 1995). Although many urea blocks are promoted, please note that our block is urea-free. There is a proven inability of the rumen microorganisms to synthesize sufficient quantities of all amino acids needed to prevent deficiencies or imbalances which may be a major factor responsible for the lowered animal performance obtained with urea diets (Chalupa 1968).

Pasture

Sustainable pasture development is possible with some advanced planning and the use of keen observation. The “Pasture Picker” is a good starting point to determine which tropical grasses are likely to succeed. The interactive “Pasture Picker” site is based on the book A guide to Better Pastures for the Tropics and Subtropics by L. R. Humphreys and I. J. Partridge (1995); it allows you to input your conditions to get the best recommendations (Figure 2).  [Editors’ Note: please also see AN #23 and a follow-up article in AN #25 about the potential of some of these fodder species to become weeds. When introducing new species to an area, please use caution and try them yourself first to ensure that the “solution” doesn’t become another problem!]

Cut and Carry Grasses and Legumes 

The Aloha House grows a biodiverse spectrum of fodder crops that we bring to our goats and cows as “cut and carry.” Humans are more adept than trampling livestock at carefully harvesting tall grass species, trees, and shrubs when they are at their prime. According to Martin (1993), “about 75% of forage consumed in the tropics is grass.” Grasses can be gathered and fed to livestock if an efficient method is employed. 

We grow Chrysopogon zizanioides (Vetiver) for slope stabilization and swale management in our water harvesting system. In addition helping reduce erosion, vetiver is also a palatable fodder species (Figure 3). We can harvest the young Vetiver with some frequency during the rainy season and maintain forage nutritional value (Table 3). 

We have also utilized Pennisetum purpureum (Napier) as a fresh cut forage for goats and cattle. Cows will readily eat it when we carry it to them in marginal pastures to supplement what is there. Napier is great because it can be vegetatively propagated (i.e. asexually propagated through cuttings). We are training three cooperatives in our region to use a variety of propagation techniques to see which are most effective for their dairy buffalo project—stay tuned! You can direct-plant napier cuttings or, if the dry season is pronounced, use some kind of nursery/cup starts and then transplant them into soil during the rainy season. We treat two- or three-node cuttings with Effective Microorganisms (EM1) and then dip them in a diverse blend of Vesicular-Arbuscular Mycorrhiza (VAM) inoculant, which is available from University of the Philippines, Los Banyos. 

The Aloha House has also utilized the Sloping Agricultural Land Technology (SALT) system since 2001. This system incorporates contour soil stabilization with legume trees and shrub perennials, as well as annual alley crops. The legume trees and shrubs can provide a nice forage option for ruminants; the legumes contribute protein for fermented feeds and contain vitamins as well as enzymes that boost feed digestibility (Watson 1985). Over the years, we have been able to save seed from prolific leguminous perennials. We have established stands and contours of Desmodium rensonii (Local name: Ticktrefoil), Flemingia congesta (Malabalatong), Indigofera, Gliricidia sepium (Kakawate or Madre de Cacao), Leucaena leucocephala (Ipil-Ipil), and Mangium acacia. These species are all well-suited for the SALT approach and are valuable legumes for goat feeds (Elvitch and Wilkinson 2008). 

Prevention of Parasite Issues with Cut and Carry

In most pastoral areas, cattle do not face a threat of parasite infestation

from the environment because they are immune to some of the common tropical pests that plague goats. Goats, however, are prone to certain parasites and are best grazed on dry pasture after the dew has evaporated or rains have dried, because barber pole worm infestation is aided by wet grass (Figure 4). Cut and carry legumes are always available to our goats and can be fed without risk of the parasite re-infecting the goats because the intestinal worm only lives in wet grasses.  It is worth the management of cut and carry to protect against this parasite in most tropical areas. 

Planned Grazing, Holistic Farm Management, Keyline Sub-Soiling, and Movable Electric Fences

P.A. Yeomen developed a concept called Keyline planning, based on the natural topography of the land; it uses the form and shape of the land to determine the layout and position of dams, irrigation areas, roads, fences, buildings, and tree lines (Ecologia 2012). His innovative Keyline plow has the ability to work subsoil without inverting the soil profile (Figure 5).

Over a period of several months to a year, grasslands can be improved by pulsing the soil with successively deeper plowings ranging from 10 cm to 20 cm to 30 cm. With air and root matter being incorporated into the soil following deeper rips, greater microbial activity in pastures can be maintained through planned grazing. Abe Collins has documented his journey and published his findings through various avenues. His Keyline improvements are discussed in simple terms in an article he wrote with Darren Doherty (2009). 

Collins has seen farmers add organic matter in pasture soils for many successive years, increasing organic matter by up to 7.3%. He utilizes complex mixtures of cover crop seeds—commonly between 7 and 20 varieties of seed in a single mix—to achieve multiple soil-health, production, and profit goals, usually in no-till farming systems (Collins 2013).

Although tractors and Keyline subsoil plows are utilized in developed countries, we have innovated a modified Keyline method for small farms that does not require fancy machinery. With the use of an off-contour triangle “A-Frame,” we are able to plant slightly downhill from the gullies to the ridges, drawing moisture to the ridges from otherwise over-hydrated gullies and thus increasing water availability throughout the year (Figure 6).

By planting on the marked lines determined by the A-frame, we are able to draw more moisture through the root system and produce forage well into the dry season.

Electric Fence vs. Tethering

Combining aggressive pasture development with intensive grazing, we are able to increase stocking density and move our livestock frequently, often 2 to 3 times per day.  With the help of a movable electric fence, our grazing cows can simulate the activities of the wild herds; historically, the wildebeest or great bison herds would graze in a tightly packed group (to keep the herd safe from predators), trampling the soil and adding manure. They would then move together to a fresh area when needed. Alan Savory modeled his herd management on this insight, as documented in his writings and TED talk.

When properly utilized, a movable electric fence allows farmers to move their herds in a dense grouping without over-grazing, so that all herbaceous plants are consumed and manure is spread evenly. When left to their own devices and free choice, ruminants will preferentially eat the most palatable greens and concentrate manure in a few areas. The least palatable species (often weeds) then prosper, shifting the pasture composition over time to these less palatable greens. Using planned grazing, Abe Collins has seen first year animals become very effective at managing aboveground pasture biomass while increasing root matter and biology below ground (2006).

Joel Salatin is another successful advocate of intensive managed grazing; he calls his method “Salad Bar Beef.” He keeps his cows on perennial polyculture, being careful not to let the cattle overgraze on juvenile greens. Each pasture species has an “S” curve growth rate. If animals are allowed to graze an area too soon, plants will not have had enough time to recover. If animals are kept away too long, grasses will have reached a “geriatric” stage during which they turn dormant and lignify, providing less nutrition (Figure 7).

Grazing should take place during the adolescent stage of a grass when optimum nutrition is available to the animal. For more information, see this video from Joel Salatin.

Movable electric fences may be too expensive for many farmers. Instead, small-scale farmers can tether their cows on a movable stake system. We were able to renovate old stands of Imperata cylindrica, commonly known as cogon grass, kunai grass, or blady grass, by tightly stocking and moving the herd according to observation of the needs of the pasture and the cows. We started by immediately grazing the new shoots after the natural seasonal burn-off that is common where cogon grass grows. (Do not feed the old standing dry cogon to your animals, because it is poor forage of low quality due to its maturation and lignification (see Figure 7). For cattle, we supplement the sub-standard graze of cogon with freshly cut and carried Pennisetum purpureum (Napier).  Cows will readily eat Napier grass when it is carried out to marginal pastures in order to supplement their nutritional needs. Any Napier that is not eaten is trampled and left as mulch. Over a period of only 2 seasons in the tropics, we’ve seen the native turf grasses and Brachiaria humidicola take over these depleted pastures and biologically exclude the cogon!

Dairy Breeds

Here at Aloha House, we milk “native” cows, probably of Jersey descent, as well as Holstein and Brahman (or Brahma), which is a breed of Zebu cattle (Bos indicus). We recommend starting small with breeds that are locally available before you start investing money in exotic breeds. Thailand has a large national dairy center, in partnership with the Dutch Government in Saraburi; it is a great resource for large and small farmers alike. As farmers gained experience in managing dairy herds, the breeding plan of the center shifted from 75 percent Holstein-Friesian to 87.5 percent Holstein-Friesian crosses. These exotic breeds are now readily available to local farmers, as they have become “common.” Thai farmers are also milking Zebu cows, and a Thai-Friesian breed has also been developed and tested (Chungsiriwat and Panapol 2009) (Figure 8).

In Bangladesh, commercial dairy herds were most successful with Holstein breeds, compared to Jersey crosses, where success was measured by milk yield and herd health/adaptability (Azam et al. 2012).

Hay as Feed

In Chiang Mai, Thailand, we were able to visit a dairy cow co-op that trains and supplies farmers with Napier hay as well as other inputs. In Sri Lanka, small-scale farmers using semi-intensive management systems depend on tethering and stall-feeding as their main source of animal feeding; by contrast, farmers in extensive management systems rely on grazing and tethering as the main source of animal feed. Animals are usually tethered and allowed to graze on paddy lands (bunds and harvest stubble and stover) (Figure 9), public spaces, and under rubber and

coconut trees in estates. The average milk production under extensive management systems was 3.9 l/AU (Animal Unit)/day, while milk production under semi-intensive management systems was 5.4 l/AU/day, showing that the extra management may be worth the boost in production for small farms (Saraiva et al. 2014). Similar results were reported by Zemmelink et al. (1999) and Premaratne et al. (2013) in the mid-country wet zone of Sri Lanka. Lower average milk yields in extensive management systems may be due to poorer feeding and cattle management.

The Great Grain Debate  

Tim Wightman, author of the Raw Milk Production Handbook (2005), addresses the question, “Should pasture-fed dairy cows get any grain?”  Typical “grain-fed” dairy cows receive a large portion of their diet in the form of grain, resulting in high milk production but with lower milk quality and with a reduced lifespan for the cows.  Pastured dairy cows with access to high-quality pasture and high-quality hay alone should be able to produce large quantities of milk.  However, giving cows a small amount of grain can provide starch to feed the microorganisms in a cow’s rumen that help the cow convert forage into body mass, milk, and energy.  According to Wightman, “The rule of thumb, in order to manage rumen activity in cows, is to feed no more than one percent of body weight per day as grain.”  We use a blend of rice bran and copra meal at 1:1 ratio with a drizzle of molasses at the end of a day of grazing.

Azolla Successes and Failures as Ruminant Feed

Azolla (Azolla caroliniana) is a fast-growing floating fern with a reported protein range of 19-30%. We grow it intensively, and feed it to chickens, ducks and fish (See AN #20- Fish Feeds, AN #25- Hog Feeds, and AN #28- Chicken Feeds)(Figure 10).

Due to our abundance of napier and pasture, we are not currently using it for ruminants. Also, we have a finite supply of azolla and feed it to our hogs and poultry. However, experiments conducted by the Vivekananda Kendra-Natural Resources Development Project (VK- NARDEP) in Kanyakumari district, Tamil Nadu, indicated that the quantity and quality of milk yield of cattle went up when they were fed with azolla to supplement marginal pasture (Prabu 2007).

Azolla was introduced as an alternative feed for dairy cows by an NGO in India. In contrast to the VK- NARDEP study above, the pilot program was found to have very poor results (Tamizhkumaran and Rao 2012).  This highlights the importance of testing innovations before promoting a community “solution,” to ensure that a new technique or idea will work in your particular environmental and cultural context. 

In experimental trials comparing Lemna minor (common duckweed), Ipomoea reptans (kang kong or morning glory), Trapa natans (water caltrap), and Salvinia cucullata (often mistaken for azolla) in India, both duckweed and morning glory had higher feed conversion ratios and high protein: 28% and 32% respectively (Kalita et al. 2007; Biswas and Sarkar 2013). These excellent fodder crops can be grown in an aquaculture system, but should be kept away from the fish so as to ensure a regular harvest (otherwise the fish would eat them). I wish that azolla had been included in the India study. We feed available azolla (after it has satisfied the need for fish, chicken, and hog feed production) to cattle by placing it in the evening feeder with our rice bran and molasses.

With floating water plants such as azolla and salvinia, a farmer must be careful not to overharvest, so that sustainable production can be maintained. A general rule of thumb (under ideal conditions) is to harvest no more than half of the floating biomass per week (or 1/7 of the total biomass per day). The trick is to keep it in the rapid vegetative stage, so farmers should monitor which way of harvesting is more productive in their system. Azolla tolerates moving water better than duckweed. Salvinia is the fastest growing, but can be invasive. At Aloha House, our best interns in charge of azolla production averaged 194 grams/sq. meter. A deep fryer basket works well for lifting the azolla while draining water (Figure 11). We harvest in the morning and let the plants drip dry for 24 hours before weighing them (Mikkelson 2017).

Moringa Forage Can Improve Milk Production

According to Lowell Fuglie (2000) in EDN 68, “New Uses of Moringa Studied in Nicaragua,” when moringa leaves constituted 40-50% of dairy cows’ feed, milk yields increased by 30%. The article shared: “The high protein content of moringa leaves must be balanced with other energy food. Cattle feed consisting of 40-50% moringa leaves should be mixed with molasses, sugar cane, young elephant grass, sweet (young) sorghum plants, or whatever else is locally available.”

Feeding Other Ruminants

Water Buffalo

The tamaraw, or Mindoro dwarf buffalo, is a water buffalo endemic to the island of Mindoro in the Philippines. It is the only endemic Philippine bovine; the species is endangered, with fewer than 500 animals remaining, and they are no longer used as draft animals. Most buffalo in the Philippines are much larger than the tamaraw. The Murrah is a domestic breed of water buffalo (Bubalus bubalis), originally from the Punjab and Haryana states of India, that is kept for dairy production. Some areas in India specialize in buffalo dairy for the production of authentic Italian mozzarella cheese.

Draft animals may require less premium feed, depending on their workload. Napier grass is good to have available and readily transported as cut and carry to the work site. All traction animals require ample water and plenty of calories for the workload. Some molasses can supplement their energy requirements at 1-5% of daily feed ration. According to EDN 53, if you work with animal traction, you should also know about Tillers International. They have specialized information and training for a wide variety of working animals in developing countries. They even have draft animals in Madagascar ripping and sub-soiling on contour for water harvesting! See this link for more details.

Oxen, yaks, camels, llamas, alpacas, and reindeer are ruminants for someone else to write about, but think through the browse and graze needed before you buy feed. Often these native ruminants can be fed with proper planning from the bounty you develop on or around your farm!

Alternative Feeds For Goats

Goats are browsers, and need a different diet than can be provided by most pastures available to a smallholder farmer. Cut and carry legumes can round out goats’ diet, but do not rely on a pure legume diet. When goats overeat lush, damp feeds such as clover, alfalfa, or cut and carry legumes, tiny bubbles of gas can get trapped in the rumen, causing bloat. It is a life-threatening condition; the foamy bubbles of gas are impossible for a goat to belch up. Protein levels vary from crop to crop but a rule of thumb is no more than 2/3 legumes and 1/3 grass and other forage should be given to goats.

Besides limited amounts of grass, shrubs, and cut and carry legume shrubs, we feed our goats a variety of palm leaves, bamboo, and neem. The neem is offered free-choice along with plenty of other greens, because it is a natural de-wormer and the goats will nibble as needed.  It is reported to be very effective on sheep as well (Chandrawathani et. al. 2006). 

Fresh coconut is another option for goat feed. Coconut farmers in our area drop the mature nuts and split them open with a machete for their goats. An American on our island has observed excellent results in his goats’ overall health and weight gain and reduced his pastoral management on sandy soils by offering coconut to his goats on a daily basis. Research shows that copra meal (dried coconut meat) increases dietary intake of protein for cattle, goats, and sheep. Copra meal is a valuable feed for ruminants and can be used as a protein supplement for grass-fed animals (Manikkamani 2011). If you use coconut by-products such as copra meal, be sure to avoid the second extraction using hexane. The chemical residues can be undesirable (Heuze V., et al. 2015).

By way of example, in North Sulawesi, Indonesia, a budding goat production system intercrops Napier grass (Pennisetum purpureum) under coconut groves. Their Crop Livestock System (coconut-forages-goat) also uses legumes such as Leucaena and Gliricidia. This is another example of an integrated and sustainable practice that helps with “the scarce supply of good forages (grass and legume) to support the feed requirements of goats.”  Of course, the manure from the feed is converted to organic fertilizer. It is a way to achieve better growth of both pasture and coconut yeild (Polakitan et al. 2001). 

Sheep 

Many straggly sheep wander the tropics, surviving but rarely thriving. Goats might be a better entry way for the novice, but lamb and sheep can have a niche in the right climate under good management. Sheep are prone to deheydration and only drink clean water from still ponds or drink pails. Moving water, streams, and rivers will not help in your watering program. They are also in need of protection from predators. Sheep are more suited for cooler climates because they can get heat stroke easily. The good news is that although there are important differences between lamb breeds, research in Brazil found that sheep can be finished exclusively on tropical pasture (Poli  et al., 2013). 

Silage for Ruminants

We utilize fermented feeds quite a bit for our fish, hogs, and poultry. However, we do not ferment or ensile any of our grasses, grains, or legumes for our four-stomached friends. We find that, on a small farm, the added labor and management negate any savings. E. coli can be problematic, because acidosis (too much acidity in the body) can result from fermented feeds and E. coli will flourish in the rumen under those conditions. Feed lots struggle with high E. coli counts because the bacteria survive the high acid (low pH) environment and multiply. The fermented feed does not culture E. coli, but rather the cows, goats, etc. produce high levels in their waste stream. The manure and feed yard are the disease vector. According to the Reference Advisory Group on Fermentative Acidosis of Ruminants (RAGFAR): “Rumen pH starts to decline immediately after feeding concentrates or silage. Concentrates such as grain, soy, or corn can cause even a more rapid decline in rumen pH than silages” (RAGFAR 2007). We are a raw dairy operation and avoid silage altogether. We do not pasteurize our milk. To keep our milk safe, we eliminate exposure to E. coli by avoiding concentrates and silage and feeding our ruminants our grass/greens; therefore, we have a lower risk for E coli contamination than a feedlot using grains only. You can read about our silage for hogs in AN #25 and adapt it for ruminants, but be careful to substitute legumes for fishmeal and to avoid soy meal. In India a technique has been demonstrated for cattle feed fermentation.

Documented Problems with Soy

At Aloha House, we do not feed soy to any of our livestock, due to soy’s detrimental health effects. Soy contains phytoestrogens and enzyme inhibitors that are problematic for both livestock and humans (IEH 2000). My concerns with soy have been previously summarized in AN #28. We at Aloha House also choose to avoid genetically modified organisms (GMOs). 

Conclusion

Farmers feeding cows, goats, sheep, and buffalo should attempt to keep purchased inputs to a minimum. Farmers must balance the dietary needs of their animals with safety, comfort, and security from theft. No matter how ideal your goals for your ruminant herd, make sure you carefully plan and manage for the overall benefit of the animals and the farmer. Most small farms in SE Asia would do well to develop and manage some amount of pasture for ruminants, combined with a cut and carry strategy. Manure should be incorporated on the farm to maintain soil fertility for the forages and plants, and tighten nutrient cycling loops so that the benefits of integrated livestock will translate into more economical and sustainable food production.

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