EXPERIENCES WITH WHOLE SUGARCANE FEEDING IN TRINIDAD AND TOBAGO
by
F.A. Neckles

INTRODUCTION

The Sugarcane Feeds Centre was established in 1976 to demonstrate the technical feasibility and economic viability of cattle production systems utilizing sugarcane as the major ration ingredient. For the first five years, it was jointly sponsored by the Canadian International Development Agency and the Government of the Republic of Trinidad and Tobago. Since October 1981, the latter has been solely responsible for the Centre's funding, operation and technical direction. There are two aspects to the Centre's work. The technical aspect is the interrelationship between animals, soils, crops and feeding. The non-technical aspect is the effort to translate the technical work into wider application - the environmental and economic factors, and the programmes and policies which facilitate, or hinder, development activity. The experience of sugarcane feeding in Trinidad and Tobago is provided from both aspects.

THE CENTRE'S PRODUCTION SYSTEM

The Centre has a total population of over 750 head of dairy and beef cattle, water buffalo (Bubalus bubalis) sheep and goats, and produces over 300 head annually. Approximately 3 500 animals (the majority Holstein-type week-old calves from the local dairy industry), have been obtained and reared from 1977 to the present time. The animal operations consist of a calf rearing unit, a cattle growth unit with males destined for beef and females for breeding, a small dairy and a small ruminant multiplication and fattening unit with about 40 breeding females. Crop operations are concerned with the growing of sugarcane and Leucaena leucocephala.

Features of the soil on which the Centre is located are lack of structure, impeded drainage, low organic matter and plant nutrient status, low pH (3.5 to 4.5) and high aluminium content. The soil, an acid ultisol, not previously in agricultural use, dries out rapidly in the dry season and quickly puddles in the wet. Three factors made it productive - the use of limestone and inorganic fertilizers at first planting, the establishment of a subsurface drainage system and the use of manure irrigation. This last factor is the most important. The manure washings from the feedlot are collected in ponds and applied to the cultivation through underground mains and a travelling sprinkler gun. The sugarcane cultivar used is B 41227, the main one of the local sugar industry. Total fresh weight yields obtained are in excess of 80 tonnes per hectare on average (Table 1).

Trinidad and Tobago experiences marked dry and wet seasons. In 1985 rainfall at the Centre was approximately 200 cm with 25 cm falling between January and May. Year-round harvesting of sugarcane is undesirable for several reasons. In the wet season brix and dry matter content are lowered and ability to use equipment is reduced, which increases cost. Trafficking compacts the soil and destroys the cultivations. There is also the prospect of soil contamination of the harvested crop. Daily harvesting is also affected by weather conditions which may lead to insecurity of feed supply.

Since 1983 a Hesston 2 000 corn forage harvester has been modified and used for the in-field harvest of standing sugarcane for silage making. A harvest rate of 4 – 6 tonnes per hour is achieved which depends on the size and shape of field, thrash content, burning or non-burning of the cane and ground conditions. No additives are used at ensiling. The chopped cane is compacted, covered and allowed to ferment. The brix of cane silage is lower (by 33 percent or more) compared to the crop at harvest but is comparable to that of freshly harvested sugarcane in the wet season. Annually six to seven hundred tonnes are ensiled in above ground horizontal silos.

Silage making in 1984 reduced the estimated cost of sugarcane at the feed trough by approximately 30 percent to US cents 14.6 per kg DM through reduction of labour-time and handling. Ensilage makes year-round use of sugarcane for larger scale zero-grazing cattle production more operationally convenient. The cost of sugarcane for animal feeding depends on how efficiently it is grown and the yield obtained. This important point is often overlooked.

FACTORS IMPORTANT TO THE USE OF SUGARCANE

The chemical composition of the whole sugarcane grown at the Centre is given in Table 2. Feeding of sugarcane takes into account sugarcane's high fibre, low crude protein content and energy content (2.7 Mcal per kg DM - Donefer and Latrille, 1979).

In the 1960s and 1970s several workers reviewed the need for the feeding of supplements and the nutritional issues involved. Based on previous work and the Centre's experiences in maintaining a year-round production-oriented facility certain feeding practices have been developed. These practices are geared toward meeting the needs of animals and sustaining acceptable levels of performance. Factors influencing the feeding strategy are briefly discussed below.

STAGE OF LIFE OF THE ANIMAL

Under the Centre's standard calf rearing system, animals are individually fed limited quantities of milk replacer and a calf starter ad libitum with weaning at 35 days of age. Fresh chopped sugarcane is offered after weaning up to a level of 20 percent of the diet DM. Over the next 35 days of age, ADG consistently averages 0.45 kg. After 70 days of age calves are then reared in groups. Since feeder calves of 170 to 200 kg liveweight typically available to a beef industry are unobtainable, these artificially reared expensive dairy calves have to be brought to this weight as quickly as possible to secure an economic feedlot throughput.

Up until 1981 sugarcane was fed at the level of 40 percent of the diet DM after 70 days of age. From 1982, in various feeding trials, the level has ranged from 5 to 30 percent depending on the other ingredients of the diet. Presently the ADG obtained at the lower levels of sugarcane ranges from 0.70 to 0.90 kg compared to the previously obtained 0.40 to 0.50 kg. As animals grow and develop their ruminant status, increasing levels of sugarcane are included in the diet.

The first lifetime feeding trial utilizing 10-month old calves averaging 160 kg liveweight was started in April 1982 and lasted nearly one year. It compared the effects of energy supplementation using rice at 0, 5 and 10 percent DM levels in 50 percent sugarcane diets. Molasses with a maize-soyabean based supplement containing non-protein nitrogen (NPN) made up the rest of the diet. Average daily gains of 0.42, 0.60 and 0.63 kg were obtained. Evaluation of feed conversion efficiency, income over feed costs and slaughter data was done. A nutritional model for feeding sugarcane Life Cycle Feeding was proposed by Garcia, Neckles and Benn (1982) based on this and other work. In this model, initially smaller quantities of sugarcane in the diet DM are offered to animals in the lower liveweight ranges which increases to approximately 50 percent of the diet DM for the higher liveweights (see section on dietary fibre, energy and protein levels below).

COMPOSITION OF NON-SUGARCANE INGREDIENTS

Sugarcane has been fed with a wide varety of both energy and protein supplements with varying results. The chemical composition of these non-sugarcane ingredients is important. For economic and national development reasons, supplements utilized with sugarcane have shifted as far as is feasible from the standard soyabean meal and maize which were available only through importation and relatively expensively. Being low fibre, high energy or protein sources, the maize and soyabean were conducive to feeding higher sugarcane levels in the total diet. When replacements were sought few direct substitutions were possible with the exception of broken rice/end bits for maize. Generally the available substitute sources of protein or energy (e.g. poultry byproduct meal (PBM), dried citrus pulp, wet spent brewer's grains, rice polishings, wheat middlings, dried Leucaena forage, etc.) while lower in costs are all of different composition and feeding value of the standards (maize and soyabean meal). Introduction of the local substitutes into the diets generally increases fibre and lowers the energy and/or protein per unit of substitution. Presently NPN is not utilized to any extent in the sugarcane feeding done at the Centre. Previously, it had been fed to growing animals over 150 kg liveweight, contributing about 30 – 35 percent of the total calculated crude protein in the diet. In 1982, urea was fed to calves under 100 kg liveweight and while contributing 20 percent of the total protein resulted in ADG of 0.63, 0.65 and 0.75 kg for sugarcane levels of 40, 30 or 20 percent, respectively. The diets were 20, 30 or 40 percent for broken rice/end bits, respectively (SFC, 1982). It was considered that NPN use however, depends on the presence of high levels of digestible energy and that this is not generally compatible with use of the substitute energy sources available and high to medium levels of sugarcane in the diet DM.

TOTAL DIETARY FIBRE, PROTEIN AND ENERGY LEVELS

The National Research Council of the USA feeding standards are used in the formulation of diets which are designed to meet the requirements for crude protein and digestible energy for the stage of life and production of the animal. Table 3 is used to illustrate changing sugarcane-molasses levels in the diet of lactating cattle fed by stage of lactation. This example does not contain NPN. Up to 20 percent of the total protein has been supplied by NPN in dairy diets, however.

The feeding strategy makes use of more efficient feed conversion obtained in young growing stock compared to animals approaching mature weights. Diets fed to animals up to 150–200 kg liveweight are designed to be low in ADF and high in energy and protein. This means low levels of sugarcane since byproducts are combined with soyabean meal and maize in the diet. Table 4 shows the diet composition and the results obtained after 56 days of feeding. These results are typical of those obtained with other combinations at lower level sugarcane feeding, i.e. up to 30 percent sugarcane in the diet DM.

In the latter part of the animal's feeding cycle, sugarcane level also exerts influence on the characteristics of the carcass obtained. Between 1980 and 1983 carcass information was collected from animals fed different levels of sugarcans. Table 5 presents a partial summary for the Holstein-type animal. The trend is that finishing animals on high energy, low sugarcane diets resulted in lower dressing out percentages due to increased trimmable fat (the local market discriminates against fat). Rib-eye areas taken after the 12th rib generally increased with increasing sugarcane level in the diet. This was another factor which led to the emphasis on high growth rates in early life on low sugarcane diets in preference to high grain-low sugarcane “finishing” diets.

The model for utilizing sugarcane in feed for ruminants either for beef or milk production is based on the relationship that as the percentage of sugarcane in the diet is increased, average daily weight gain decreased (Pate, 1981), and milk production of crossbred Holstein of the Centre also decreased according to the relation: y = -0.13x + 16.35 (r=0.92) (SFC 1983).

THE IMPACT OF THE CENTRE

The Centre has been working with farmers continuously since its inception. Most of the work has been with small producers on 5–8 ha farms established by the State. Farmers have improved their feeding practices, management and animal rearing through contact with the Centre. A study of the Department of Agricultural Extension, University of the West Indies, evaluated seven farms and found that their feeding practices were reversed over the years. Where formerly feeding was in the proportion 68:32 percent bagged concentrate to grass, sugarcane, molasses and byproducts, this was changed to 35:65 percent, respectively, after involvement with the Centre (Dolly and Reid, 1986). The largest producer utilizing sugarcane to feed up to 100 head closed the operation in 1984 due to the inability to market animals and increases in feed prices. Another producer with a beef feedlot as part of a productive dairy enterprise eventually closed the feedlot, again for want of a market.

The Government-owned sugar industry is an important source of foreign exchange, earning US$ 96 million in 1986. Production of raw sugar was approximately 92 000 tonnes from approximately 35 000 ha. Since costs of production are high the industry receives an annual subsidy of approximately US$ 80 million. The subsidy is less sustainable under current economic conditions and the Company is attempting to increase efficiency of sugar production while diversifying over a ten-year period into production of rice, citrus, coffee, cassava, pigeon peas and other crops on 4 000 ha. Plans are to utilize 1 000 ha for milk and beef production. The Company already owns about 600 head of water buffalo selected and developed over the past 30 years for beef production and a 250 head dairy based on Holstein-type animals. It has not yet committed itself to sugarcane use as a feed but has switched toward feeding of byproducts. The Centre has proposed that a livestock complex integrating sugarcane production, other crop growing and processing, byproduct feed utilization, milk and meat processing, be established as part of the diversification exercise. This will provide economics of scale. Suitable technology should also be supplied for the development of existing small farms.

PROSPECTS FOR THE FUTURE

The philosophy of the Centre is that ruminants should be fed as far as possible from local feed resources which should arise from increased agricultural activity aimed primarily at food for human consumption. With production and processing the quantity and range of byproducts available for animal feed will increase. Integration of production must occur at the farm level and at the sector level as exemplified by the Centre's programmes and at the national level. Proper marketing with fuller utilization of animal carcasses is also necessary. Collaboration between the Centre and another state institution, geared towards swine slaughter and processing has resulted in the successful marketing of chilled beef. The full value of the animal is still to be obtained since all inedible products are rendered. A modern slaughter facility would make fuller use of the animal. Animal production is often discussed in terms of feeding, weight gain, management, etc. and proper marketing is often overlooked. In Trinidad and Tobago the previous policy of unrestricted imports was changed in 1986 and attention is now being given to marketing at the national level. The Centre's role is not only to demonstrate the use of sugarcaneas a feed but also to influence those who make policy for agricultural development.

REFERENCES

Dolly, 1986 D. and Reid, N. An evaluation of the Sugarcane Feeds Centre. Department of Agricultural Extension, Faculty of Agriculture, University of the West Indies, St. Augustine, Trinidad, W.I. (In press).

Donefer, 1979 E. and Latrille, L. Description of sugarcane feeds: nomenclature and nutritional information. “Standardisation of analytical methodology for feeds” in Proceedings of a Workshop, Ottawa, Canada, 12–14 March 1979. Eds. W.J. Pigden, C.C. Balch, and M. Graham. IDRC - 134C, 79–86.

Garcia, 1982 G.W., Neckles, F.A. and Benn, A. Sugarcane as a feed for ruminants. In Proceedings of the IV Regional Livestock Meeting. 29 Sept. to 1 Oct. 1982, Georgetown, Guyana, Department of Livestock Science. The University of the West Indies, Faculty of Agriculture, St. Augustine, Trinidad & Tobago.

Pate, 1981 F.M. Fresh chopped sugarcane in growing steer diets. J. Anim. Sci., 53: 881–888.

Sugarcane Feeds Centre. 1982 Annual Report: October 1981 – December 1982. The Sugarcane Feeds Centre, Longdenville, Trinidad, Trinidad and Tobago.

Sugarcane Feeds Centre. 1983 Annual Report: January-December 1983. The Sugarcane Feeds Centre, Longdenville, Trinidad, Trinidad and Tobago.

EXPERIENCIA EN EL USO DE LA CAÑA INTEGRAL EN ALIMENTACION ANIMAL EN TRINIDAD Y TABAGO
por
F.A. Neckles

El Centro de piensos a base de caña de azúcar, establecido para demostrar la viabilidad técnica y económica de la caña en la producción de carne de vacuno y de leche, mantiene a más de 750 rumiantes (vacas lecheras y de engorde, búfalos de la India, ovejas y cabras) en un sistema intensivo sin pasto. Dos características importantes del sistema de producción de cultivos para el ganado son la utilización de estiércol en el cultivo de la caña y la recolección mecánica durante la estación seca para la producción de ensilaje.

Las estrategias de alimentación animal entrañan la optimización de la proporción de caña en la materia seca de la dieta con arreglo a (i) la etapa de la vida del animal, (ii) la composición de los ingredientes del pienso distintos de la caña de azúcar, (iii) el suministro diario total de fibra, proteínas y energía en relación con el rendimiento requerido de los animales, (iv) la eficiencia de transformación de los piensos, y (v) las características de la canal. Después de realizar un análisis de la relación costos-rendimientos, la dieta se basó en productos y subproductos locales de la agricultura y las industrias agrarias. El trabajo con los agricultores ha tendido a desarrollar la capacidad de gestión y técnica, que son condiciones importantes para una producción intensiva exitosa. Las importaciones de carne y leche son considerables, pero la limitada capacidad para elaborar y comercializar la producción local dificulta el desarrollo.

Las propuestas relativas a la diversificación de la industria del azúcar ofrecen posibilidades para sistemas de producción agropecuaria en mayor escala cuando puedan movilizarse los recursos técnicos, financieros, de comercialización y de otro tipo necesarios. Se promueve la alimentación del ganado a base de caña en el marco de un esfuerzo de producción agrícola integrada.