STUDENTS' ABSTRACTS

                                

	Agricultural Abstracts	Animal Science
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SOIL SCIENCE ABSTRACTS

Potassium status of selected soil types in Guyana

Studies were done on two rice growing soils in Guyana (Mara Clay and Litchfield Clay) to investigate the potassium status over time and to see if fertilizer application is necessary.

The soils were subjected to three moisture levels (Dry, 40% moisture and Flooded) and two fertilizer levels (0 and 0.034 cmol K/Kg soil).

It was observed that the total potassium content of Mara Clay is more than that of Litchfield Clay. However, the trends in fixation were very similar. The soils under all three moisture regimes had a peak fixation point at 42 days, the same release after which fixation peaked again at 70 days. Only Litchfield Clay in the 40% moisture content varied slightly with peak fixation occurring at 28 days.

It was also observed that although fertilizer application influenced the total amount of potassium in the soil, the fixation trend is similar to that of the unfertilized soil.

Both of these clays were found to have adequate potassium for plant growth. Therefore, application of potassium in these soils is not necessary. However, fertilizer application will increase the amount of available potassium and generally decrease the rate of fixation of potassium.

A preliminary investigation to determine the most suitable duration for composting of fresh filter mud was undertaken in the compound of GUYSUCO’s Agricultural Research Centre at LBI, during March to June 1999. Quantities of available nutrients and total salts at various stages of decomposition were monitored. Three unreplicated treatments were investigated and included (i) filter mud left undisturbed, (ii) filter mud plus urea turned once at seven days and (iii) filter mud turned every seven days. The addition of urea to the filter mud heap appeared to increase the rate of decomposition of the filter mud. The lowest C:N ratio was obtained during the eight week of decomposition when urea was included in the heap. The organic solvent Ethylenediaminetetraacetic acid (EDTA) extracted larger amounts of exchangeable cations compared with that extracted with water. EDTA extractable cations decreased as decomposition of filter mud progressed.

The impact of salinity hazard has caused an economic setback in the rice industry in Guyana, in the first crop if 1998. This pot experiment seeks to find out the effects of salinity in irrigation water at increasingly different levels to rice varieties Rustic, BR 240, F₇-10 and BR 444.

Four (4) salinity treatments (including a control) were imposed on each particular variety on Litchfield clay. Each particular treatment was replicated 3 times. The experiment was a 4 x 4 factorial expression. After the soil was analysed it was placed in pots (25cm height, 23cm diameter) and filled to about 15-20cm. The soil in the pots were subjected to flooding and prepared for sowing. Pre-germinated seeds of each variety were sown in respective pots. Treatments were applied 10 DAS and water level was maintained 4" above soil surface until heading. Salinity levels were constantly monitored and maintained by the use of the electrical conductivity meter. Fertilizer was applied in split application. Plant height and tiller count were done at various intervals of plants growth and grain yield and its components taken after harvesting and drying the grain and straw. A complete soil analysis was done after harvesting for the soils in the various treatments.

Rustic, BR 240, and F₇-10 were salt sensitive (1000 - 1500 microsiemen per centimeter (umho cm^-1)) with Rustic being the most severely affected variety while BR 444, showed little or no effect of salinity at increasing levels.

There were significant differences in plant heights, tiller count to a less extent, grain yield and dry weight analyses. BR 240 showed considerable effects in plant height, grain yield and dry weight analysis especially at increasing salinity, more conspicuously at the extent of the highest treatment.

F₇-10 showed grain yields and plant height differences mostly at the highest salinity level of 2500-3000 umho cm^-1. Plant height differences were prominent at the early growth stages.

BR 444 on the other hand seems to be the tolerant rice variety at the maximum salinity level of this experiment.

The use of gypsum as an ameliorant for soil salinity and acidity

The effectiveness of Gypsum (CaSO₄ -2H₂O) as an ameliorant for reducing soil salinity and soil acidity was studied in separate laboratory trials using two different soil types. The Whittaker series #37 used in the salinity study had an electrical Conductivity measurements in saturated paste extract (ECe) of

3.2mScm^-1 in the sub-soil. The Stewartville series soil #23 used in the acidity study had a pH value of 4.7 and an interchangeable acidity of 7.25me per 100 grams of soil. The incorporation of gypsum in the sub-soil was the most effective treatment for reducing sub-soil salinity. Placement of gypsum on the surface aids in the reduction of sub-soil salinity. Gypsum was comparatively less effective than Low Grade Phosphate - Lime (LGP-L) in reducing soil acidity Gypsum applied at 60 percent of the full rate of application was just as effective as the full rate of application in reducing soil acidity.

Laboratory studies were conducted on 7 sugar cane cultivated clay soils and an unreclaimed saline soil either treated or untreated with K to determine their ability to release native and applied K. One sample of each soil was treated with 200 cmol K/Kg soil, whilst another sample was untreated. Both samples were then subjected to 10 leachings each with 25.0 ml 0.01M NaC1, 0.01M MgCl₂ and 0.01M SrCl₂. Exchangeable K was also determined with 1.0M NH₄OAc. Significant positive correlations existed between native K released (from treated and untreated samples) and exchangeable K, C.E.C, and K saturation. Native releases from treated samples correlated positively with percentage clay of soil. Significant negative correlations existed between K adsorbed on treated soils and (i) exchangeable K, and (ii) K saturation; whilst a positive correlation existed with percentage silt + clay. NH₄ OacK alone was not shown to be an adequate measure of available K, but when combined with other soil parameters, it could aid in predicting soil K release and adsorption. Of the three electrolytes used to displace K from soils (either treated or untreated), the efficacy in decreasing order was found to be SrCl₂ >MgCl₂ > NaCl. There was a positive significant correlation between the 3 electrolytes in their efficiencies to displace K with respect to their relationships. Soil characteristics important for predicting native K release from treated and untreated soils were found to be soil Mineralogy/Texture>K Saturation>Exchangeable K>CEC>pH> location. This study reclassified the responsiveness of the soils as either net K-releasers or as net K-adsorbers. The net K-releasers of applied K include in decreasing order Whittaker #37 clay (LBI)>Whittaker #37 clay (Rose Hall)>Whittaker #37 clay (Albion). It was realized that Tain #9 clay even though reclassified as a net K-releaser, may well be border line between net K-releasers and net K-adsorbers when other parameters were considered. Everton #31 a silty clay was shown to be severely deficient of native K. The low proportion of applied K fixed by the net K-adsorber soils (2.71% to 15.82% in presence of Mg; and 5.56% to 7.77% in presence of Sr), implies that K could be applied at an economical rate if crop response is noticed (based on field K-trials). Hence, serious considerations should be directed toward applying K to all cultivated soils studied. That is, K application on Everton #31 a silty clay, Onverwagt #41d clay and Corentyne #11d clay must be continued; and K application on Tain #9 clay and the Whittaker #37 clays should be initiated.

Abstract - The project was aimed at providing information on the inherent ability of sugarcane soils to release potassium, also to provide information as to the kinetics of potassium release in the presence of different electrolytes.

The soils tested were Whittaker #37, Corentyne #11d, Tain #9, Everton #31a, Onverwagt #41d and an unreclaimed saline soil. According to previous nutrition studies 31a and 41d are responsive to potassium fixation whilst 11d, 9, and 37 are not.

Potassium was extracted from soil type using 0.01M soultion of each electrolyte (NH₄CI, BaCI₂ and CaCI₂). A second study involved the pre-treatment of the soil with 5x10 ^-3 M KCI, then extraction using the different electrolytes above to check for fixation. All extractions were done ten times.

The unreclaimed saline soil released the highest potassium across all electrolytes. Everton released the second highest level of potassium. Whittaker from sugar Estates - LBI and Rosehall released the least amount of potassium. The other soil types were not significantly different.

The electrolyte which extracted the highest K across all soils types is NH4C1. The amount of potassium extracted by the three electrolytes used was compared with the potassium extracted by the standard electrolyte (NH₄ OAc). It was found that from the first extraction the three electrolytes extracted less potassium than NH₄ Oac, especially BaCl ₂ and CaCl ₂. However, the total amount of potassium extracted by the three electrolytes was significantly more than that extracted by NH₄ Oac.

The potassium released from the soil after being spiked with KCl showed that Whittaker retained the highest amount of potassium. The unreclaimed saline soil did not retain any amount of potassium.

This project was done to determine the effect of water depth on seedling emergence and vigour on three rice varieties - F₇10, BR 240 and BR 444. Water depths used were at 0, 5, 10, 15 and 20 cm.

Fifty healthy pre-germinated seeds from a particular variety were sown per pot. Water depth was maintained up to the required level on a daily basis. The percentage emergence was measured after 7 and 14 days. Seedling height and dry weight (vigour) were measured 14 days after sowing.

The percentage emergence was not significantly different for each variety and it remained constant at 7 and 14 days after sowing among the first four treatments. However, there were significant differences among these treatments and the fifth treatment. Seedling height increased as water depth increased up to the 5 - 10 cm level and then decreased with increasing water level for all three varieties used. Generally, it appeared as though F₇10 and BR 240 can grow effectively in 5 - 10 cm water while BR 444 can do so in approximately 10 cm water.

Studies were done to estimate losses of applied nitrogen (N) by uptake, runoff and volatilization. The experiment field was 1.053 hectares (ha), and was divided into four replicate blocks. Each block consisted of four treatments (8 rows) and are outlined below: (1) Control (no N applied), (2) Sulphate of ammonia (SA), (3) Urea and (4) a mixture of urea and sulphate of ammonia. A rate of 106 kg N ha-1 was applied in all of the treatments except for the control. Leaves and stalks were analyzed for their dry matter content (DMC) and nitrogen content (g N/Kg DM). The volatilization study was conducted using boric acid to trap N given off from the various treatment plots. Runoff water was collected in buried plastic containers and analyzed for total nitrogen. Applied fertilizer nitrogen was mainly lost from the soil by plant uptake, while insignificant losses by volatilization occurred three days after nitrogen was applied. The runoff trial done in this study did not allow nitrogen losses in runoff water to be interpreted per unit area therefore loss of nitrogen could not be calculated based on amount aplied. Urea showed the greatest losses in uptake, while sulphate of ammonia recorded the highest losses for volatilization and runoff.

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An Assessment of the Impact of the Agricultural Extension System in Guyana

Surveys were conducted in Region 2, 3 and 4 to do an assessment of the impact of the agricultural extension system in Guyana utilising interview, questionnaire, key informants and participants observation. It was found that the extension officer to farmer ratio was approximately 1:136; there were no technical support received by 69% of the farmers. There were administrative control in the extension service department and transportation caused a major problem to 70% of extension workers. The technical capabilities and education level of the extension workers were found to be adequate and 67% indicated they are still prepared for the job. Investigations to find out if any programmes were available for extension workers to visit farmers fields accompanied by the National Agricultural Research Institute (NARI) resource personnel indicate that no regular routine visits were made. 90% of farmers interviewed stated they were informed of agricultural work through other farmers as compared with 6% who got their information from extension workers; 92% of extension workers stated that the Agriculture Ministry expectations of them were clear and understood. 21% of the extension workers feel there is the need for a policy for agriculture extension in the Ministry of Agriculture.

Budgeting - The Use of Simulation to Achieve and maintain effective crop production enterprise

This project provides an account which encompasses maintenance of Effective Crop Enterprises (Bora and Boulanger) through budgeting. The philosophy behind this is based on the fact that simulation can be performed on these crop budgets for various scenarios and thus foretell, verify or nullify statements or beliefs. These statements or more scientifically, hypotheses are related to measures of production level. This philosophy further demonstrates that such simulation can be used to aid in complex decision making and testing of strategies before implementing.

To achieve the objectives of this project, evaluation of farming practices for 2 crops, in 2 areas of region No. 4 (Ann’s Grove and Mahaica), was carried out, hypotheses formulated and tested so as to reject or fail to reject and thus form conclusions and aid recommendations.

Scenarios which were tested through simulation for Bora, included, use of cash payments for labour (c), use of treated seed (T), production during moderate flood periods (F1) and moderate drought periods (D). Those scenarios tested for Boulanger included use of cash payments for labor and production during moderate flood periods.

From testing of hypotheses, it has been discovered, that, should cash payments for labour be enforced for bora production in both areas, gross margin will reduce by over 50%, causing production to cease being feasible. Also, if treated seeds are used instead of those saved and conditioned by farmers, increase in gross margin is realised.

Of note, is that increase of unit price during moderate drought periods, maintains feasible production of bora in Mahaica, but not in Ann’s Grove. However, increase in price during periods of moderate drought does not promote feasible production levels for both areas.

For Boulanger production, hypotheses testing revealed that in all scenarios investigated and tested, production level remains above feasibility level.

The Biology and Control of Momordica charantia (Band Carilla)

Momordica charantia is a problem weed to some cultivated crops in Guyana e.g sugar cane. Its life cycle was investigated from germination to the production of matured fruits. Factors such as dormancy, mode of germination, seedling emergence and stages in developmental growth of plant after emergence were examined and recorded, with respect to germination percentage and new plant parts related to time. The weed’s response, to four chemicals (Aclonifen, Banvel, Grandstan and oxytril) was tested using a visual method to measure these responses. It was shown that dormancy does exist (55% germination) when compared with seeds treated to break dormancy (80.81% germination). A seed could remain viable for at least 6 months. The mode of emergence is active hypocotyl and this vine emerge best at the planting depth of 1-3 inches. 12-15 days is the time period for maximum emergence after planting, and six weeks later mature fruits are produced. Alconifen and Grandstan completely controlled the weed three weeks after application, as against Banvel and oxytril which showed little or no control.

The efficacy of two neem-based insecticides versus a synthetic chemical (PESTAC) against the cabbage budworm-Hellula phidilealis

Two field trials were conducted to examine the efficacy of two neem-based insecticides to control the cabbage budworm Hellula phidilealis on pakchoi. Neemactin, a commercially formulated neem insecticide, was used at rates of ½ ml, 2 ml, 4ml & 6ml/ 1 water and Neem kernel at 60g, 45g, 30g, & 15g/ 1 water. These were compared with a synthetic insecticide - Pestac, at a rate of 1-2ml/1 water to test their effectiveness. Foliar application of these insecticides was conducted once every 6-7 days for the entire cropping period. Treatments with Neemactin and Neem kernel extracts showed no significant difference to that of the Pestac, except Neemactin at very low concentrations (½ ml and 2ml/1 water). The yields were affected by the application of neem-based pesticides. It was observed generally that plots treated with neem-based pesticides yielded the lowest while those treated with Pestac yielded the most. There were no significant difference among plots treated with Neemactin, nor among those treated with neem kernel extract. To ascertain whether neem extracts would have an effect on the taste of treated pakchoi, a palatability test revealed that those treated with 2ml Neemactin/1 water gained the highest mean score of 3.857 (out of 4). This was not significantly different from that of Pestac treated pakchoi. On the other hand, the plot with the lowest concentration of neem kernel extracts (15g/1 water) received the lowest mean score, 1.714 out of 4.

The Marketability in Georgetown of Selective fresh produce from Black Bush Polder

-This project seeks to establish the validity or otherwise of the hypotheses that (a) the average price of fresh produce from Black Bush Polder is fifty percent greater in Georgetown (b) there is a 10% level of spoilage of the produce on arrival in Georgetown and (c) 70% of vendors have a preference for produce from Black Bush Polder over produce from elsewhere. A survey was carried our in the two locations, that is, Black Bush Polder and Georgetown, using the questionnaire approach. Three categories of persons - farmers, vendors and customers - were interviewed. The results of the survey and analysis did not, however, fully support the above hypotheses since (a) the price differential between Black Bush Polder and Georgetown on five (5) selected produce was over 250% (b) there was approximately 10% level of spoilage and (c) 87% of the persons interviewed preferred produce from Black Bush Polder.

Biology and control of Caladium bicolor (Cabbage Cole)

Two experiments were carried out to understand the rate at which whole and chipped corms of Caladium bicolor developed at different depths in sugar cane cultivated soils and to select an effective post emergent herbicide against the said weed.

A high percent of whole corms at the surface remained dormant up to 73 days after planting then start to emerge at a faster rate than those at (7.623 cm) 3", (15.24 cm) 6" and (22.86 cm) 9" depths. However, chipped corms at the surface desiccated and died. Approximately all corms at the different depths remained viable. 40% of corm found in field were between depths of 2.6" (6.6 cm) and 5.1" (12.9 cm).

Four herbicides namely:- Starane, Grandstand, 2-4 Dichlorophenoxyaceticacid (2 - 4D) (control) and Challenge were used to test the efficacy on Caladium bicolor. At 14 and 21 days after treatment, Starane and Grandstand showed moderate control. However, the effectiveness of all four herbicides was reduced at 42 days after treatment. Further screening of herbicides should be done to check the effects of chemicals on sugar cane plants.

The sporadic flowering of pineapple is not a desired feature for commercial ventures, therefore, a comparative study was done to determine the effects of ethrel on the flowering of pineapple plant.

The Montserrat varieties aged 9, 10 and 12 months were treated with 25 and 50 ml of ethrel solution in a replicated trial design.

There were no differences between the two concentrations, however the ages of the pineapple plants showed significant differences. The 9 months pineapple plants produced basal slips but the 10 and 12 months produced none. The top and bottom diameters of the 9 months pineapple plants were greater than the 10 and 12 months. The 9 months pineapple plants had larger fruits compared with the 10 and 12 months. The only difference between the 10 months and 12 months pineapple plants were the lengths of the crown of the fruit, where the 12 months possessed larger crowns. There were no significant differences in the length of the fruit for all three ages used in experiment.

It can be concluded that age of the pineapple plants used had a greater impact in response to the treatment of ethrel. Therefore, in the event of the unavailability of Naphthalene acetic acid (NAA) tablets ethrel may be a suitable alternative.

Sustainable agriculture has become a domain of top priority in the agricultural and rural development of the contemporary world. It has helped to promote the agricultural economy and sustainable social development, to better protect ecological environment and reasonably utilize the resources. The past few years have witnessed rapid progress of sustainable agricultural technology and great achievements have been made in the areas of crop breeding, plant protection, environmental protection, bioengineering, rural energy utilization and soil and water management. This report sought to discuss the results of a 22 week programme aimed at taking some of this sustainable agricultural technology to a group of fish farmers along the Essequibo Coast and in Pomeroon. In planning the programme, the "planning environment" was considered and internal factors as well as factors external to this environment were looked at. A framework was set up for the planned programme and the activities, namely demonstrations and seminar, which were evaluated at the end, were carried out according to the framework’s schedule. Through the whole-hearted participation of the farmers they were able to obtain some positive results; results which represented a forward movement. This was exemplified by the fact that persons not involved in this activity were looking to become involved and some of those already involved, were contemplating expanding their operations. This was even as the farmers had encountered adverse weather conditions in the form of excessive rains that resulted in flooding and the fact that they were dependent on a very inappropriate diet being used as fish feed. This however, did not deter the farmers from adopting the new techniques demonstrated to them and they were convinced that come harvesting time, they would record an increase in yield. Although there were definite improvements in the social, institutional, environmental and technological categories, it was concluded that this programme merely provided the impetus for the farmers involved to strive towards higher and higher levels of sustainability. To ensure this, it was recommended that the programme be continued with critical areas being identified.

The latex and extracts from the leaf and bark of Manilkara bidentata (Bulletwood) were evaluated to determine their potential fungitoxic properties. Three common pathogenic fungi were used as the test organisms. These were Aspergillus flavus, Rhizoctonia solani and Rhizopus stolonifer. Each of the test fungi were cultured for a seven-day period on PDA growth media which had been amended with the varying extracts. The latex treatment was found to exhibit the highest level of fungitoxic actiity as against the other treatments (P < 0.05) on all the test fungi. Some amount of fungitoxic activity exhibited by the latex may be attributed to the fact that its contents include dipterenes, starches and alkaloids. Alkaloids in particular are known to exist in a wide range of forms, some of which are known to exhibit fungitoxic properties.

Region Ten, Upper Demerara Upper Berbice, starts at Moblissa along the Linder Soesdyke Highway, consists of some areas along the Berbice River, is bordered to the west by the Essequibo River and has the Demerara River running through its lands.

An activity that is engaged in by a number of individuals in region ten is agriculture. This, has attracted both males and females, ranging from sixteen (16) to seventy (70) and older. These persons have been engaged in agricultural activities, whether it is rearing of livestock or the cultivation of crops.

Region ten consists of sands, with colours ranging from white to black, loams and clays. These soil types allow farmers to cultivate their crops and build suitable housing facilities for their livestock.

Agriculture in this region is practised on three levels, subsistence, commercial and semi-commercial activities. Crop production is the dominant farming activity followed by mixed-farming and livestock production. Livestock operations are either intensive or semi-intensive, with poultry being the dominant intensively rearer species and cattle the dominantly reared semi-intensive species.

The produce/products from these agricultural ventures are sometimes processed e.g. pickling of pork beef and peppers and the solar drying of minica and peanuts. These produce/products, are sold within and outside of the region, with Linden having the largest market for these agricultural products/produces.

Some farmers are also engaged in lumbering and charcoal mining. These areas are not as developed as the crops, livestock and mixed farming operations.

The agriculture sector in region ten is currently being revitalised. More persons are becoming involved in this practice daily and as the demand for the agricultural produce/products increase, farmers of region ten may one day be able to supply enough of these commodities to meet the needs of the residents in and out of the region.

Extensive use of a particular group of synthetic pesticide to control a particular insect pest has resulted in pest resistance, resurgence and damage to the environment. Monocrotophos has been used in Guyana to control paddy bug for the last 28 years. Yet grain damage caused by paddy bug is high. This study attempts to compare the efficacy of neem products against Monocrotophos in controlling paddy bugs; to determine paddy bug population at various time intervals after spraying with neem products and Monocrotophos; and to determine % damage grain from treated plots.

Neem kernel extract, three commercial neem products (Agroneem, Neemactin and Neem-X) and Monocrotophos were used. The test variety was BR 444. The experimental design was a RCBD with four replicates. The area was divided into 24 plots each of 75m² with a l m "buffer zone" between blocks. Routine agronomic practices were carried out namely, controlling water level, pesticide, and herbicide and fertiliser application.

Bug counts were taken from 70 to 87 days after sowing (DAS) and spraying was done at 90 DAS. Bug count was taken at 1, 4, 7, 10 13 and 18 days after spraying to compare efficacy and % damaged grain was determined at the end of the experiment.

Plots sprayed with Neem-X had lowest % damaged grains whilst plots sprayed with Agroneem has highest % damaged grains. There was no significant difference in % damaged grain between Moncotophos and Neemactin, Neem-X and Neem kernel. Bug population was lowest for Monocrotophos at 1, 4, 7 and 10 days after spraying whereas Neemactin and Neem kernel had lowest population at 13 dqys after spraying. The residual effect for all treatments lasted for a 24 hours period.

Evaluation of three local and five introduced varieties was examined on Whittaker clay to determine their yield potential, growth characteristics and cooking qualities. The local varieties Clemson Spineless, OK-011 and introduced variety Santa Cruz were the high yielding with yield of 7.8, 7.4 and 6.7 t/ha respectively. Louisiana Green Velvet, Clemson Spineless and Long stick gave good flavour while Artist, Louisiana Green Velvet, Clemson Spineless and Better Five were moderate in their exudates production. The introduced varieties Santa Cruz, Emerald Green Velvet, Louisiana Green Velvet and the local varieties, OK-011 produces tender pods, which are suitable for the local market.

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The purpose of this experiment was to evaluate the effects of a commercial concentrate and different supplements formulated from agro by-products on the performance of growing lambs. These rations were evaluated based on weight gain by lambs and economic analysis. This experiment was conducted at NARI’s livestock farm Mon Repos, E.C.D. Sixteen Barbados Blackbelly crossed weaned female lambs approximately five months old were used in a completely randomized design. Four lambs were randomly assigned to one of the four treatments (T₁, T₂ , T₃ and T₄ ). There were significant differences (P<0.05) among lambs fed T₄ and the other three Treatments. However, there was no significant difference (P<0.05) among lambs fed T₂ and T₃ with T₁ recording the lowest daily liveweight gain. There were strong correlations between cumulative liveweight gain over feed intake for the four treatments however, lambs fed T₄ were not as strong as T₁ T₂ and T₃. Treatment four was the most economical in terms of cost per unit grain, with Treatment one being the least economical feed.

A feeding trial was conducted to determine the most economical dietary protein level for the Jamaican Red Tilapia reared locally. Four crumb feeds containing 28%, 30%, 32% & 34% crude protein were fed to Tilapia weighing 39.4(g)- 45(g) in 0.86m³ cages. The treatments were replicated thrice in a completely randomised design (CRD). Each cage contained ten fishes. The diets were fed at a rate of 5% of the wet biomass in two equal portions per day for 8 weeks. Weight gain and apparent feed conversion rations (FCRa) were improved at the 34% crude protein diet, while the 34% and 32% diets were more economical to feed than the 28% and 30% diets. The data suggested that it was more economical to offer the 34% protein feed.

One hundred day old chicks were brooded for two weeks, then randomly separated and reared utilizing the trough and can system. They were fed similarly for six weeks. Their rate of weight gain, mortality and feed efficiency were recorded. Results revealed no general differences between the two systems except in week 8 which showed that the can system had better feed efficiency than the trough system.

The main constraints on poultry production in tropical countries are high feed cost and the unavailability of adequate supply of protein supplement.

This study was conducted at the National Agricultural Research Institute livestock farm. The objectives of the study were (1) to determine the weight of peking ducks, (2) to investigate the cost for rearing peking ducks and (3) to determine the carcass weight of peking ducks when fed ration of different protein source at the same feeding level.

Using a complete randomised design experiment, twenty-five ducklings were randomly assigned to one of four treatments. T₁ comprised copra meal plus mixed feed, T₂ soya bean plus mixed feed, T₃ fish meal plus mixed feed and T₄ the control (Kaituk feed). The mixed feed consisted of corn, broken rice, wheat middling and poultry concentrate. Ducks were reared for eight weeks using a semi-intensive housing production system. During week 1,2 and 3 ducks were fed starter ration at 21% crude protein (CP); for week 4,5 and 6 grower ration at 19% CP; and finisher ration at 17% CP for the final 2 weeks. The parameters that were measured and computed in this study were initial bird weight, weekly weight, carcass weight, mortality rate, feed efficiency and economic cost analysis.

It was found that birds fed with copra meal, soya bean, fishmeal and Kaituk feed had a feed efficiency of 3.61 kg, 3.4 kg, 2.65 kg and 2.89 kg respectively. For the same ration mortality were 4%, 8%, 4% and zero respectively. The final weight observed for copra meal was 2.5 kg, soya bean meal 2.7 kg, fishmeal 3.4 kg and Kaituk 3.12 kg. It was also found that carcass percentage were 88%, 85%, and 89.3% and 83% for copra meal, soya bean meal, fishmeal and Kaituk feed respectively. Using copra meal based feed it cost $174 to yield a kg of meal, soya bean meal $187, fishmeal $150, and Kaituk $130.

Annual Review Conference 2004 Abstracts

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