Effects of harvesting age and spacing on plant characteristics, chemical composition and yield of desho grass ( Pennisetum pedicellatum Trin.) in the highlands of Ethiopia

The study was undertaken in Mecha District, Amhara National Regional State, Northwestern Ethiopia, in 2012/2013. The objectives of the study were to assess production purpose and management practices of pig and to identify constraints and generate baseline information for further research and development. From the district, 6 Kebeles (name of local administration in Ethiopia) were identified and from each Kebele 15 households were selected making the number of respondents 90. A pretested semistructured questionnaire was employed for collecting data through interview and face to face discussion with the pig owners including key informant group discussion and secondary sources. Multivisits to study sites were also made to observe the feeding, housing, and other pig management practices. The results indicated that the purpose of pig production is mainly targeted for additional income and profit for the household in which pigs are sold for external markets as pork is not consumed by local community. Results indicate that pig keepers were farmers or nonfarmers with small land holding and people engaged in other types of work. The major feed source for pig was grazing, followed by crop residue feeding and supplementing with household and agricultural by-products. Pigs are kept in house at least for the night, though the pig house was not separated by age or physiological stage. The most important constraints of pig production in the study area were feed shortage, poor access to veterinary services, and poor market linkage.

The study was conducted to determine the effect of different grass species (Brachiaria mutica, Desho, and Napier) and harvesting stages on agronomic performance, forage dry matter yield, and chemical composition. The grass species used were Desho (Pennisetum pedicellatum), Brachiaria (Brachiaria mutica), and Napier (Pennisetum purpureum), and the harvesting stages considered were 60, 90, and 120 days after establishment of grasses, respectively. The data collected included the following: percent plant survival (PS), plant height (PH), number of tillers per plant (NTPP), number of leaves per plant (NLPP), leaf length per plant (LLPP), leaf width per plant (LWPP), number of nodes per plant (NNPP), leaf-to-stem ratio (LSR), dry matter yield (DMY), and chemical composition of the grass species. Samples of grass species were harvested at different ages after establishment, weighed, and dried, and then, ground subsamples were taken for determination of dry matter (DM), ash, organic matter (OM), crude protein (CP), crude protein yield (CPY), acid detergent fiber (ADF), neutral detergent fiber (NDF), and acid detergent lignin (ADL). Results showed that morphological characteristics, forage dry matter yield, and chemical composition of the forage grasses were significantly affected by interactions of species ( ) and harvesting dates. The highest mean PH (115.2 cm), DMY (11.8 t/ha), and %CP (11.6) were recorded from Brachiaria mutica grass which was followed by Napier grass with mean PH of 87.25 cm and mean DMY of 9.8 t/ha. The %CP content of Desho and Napier grasses declined by 24%, while %CP content of Brachiaria grass declined by 26% with increased harvesting stages. Therefore, among tested grass species, Brachiaria mutica grass was recommended followed by Napier and Desho grass for on-farm evaluation and demonstration in the study area at all harvesting ages. Farmers engaged in forage grass production could seriously consider the harvesting stage as the grasses responded differently to the chemical composition.

Some nutrients in livestock feed may not be fully digested by animals own digestive enzymes, and hence important nutrients are unavailable to the animal. Although, supplementation of enzymes to farm animals has shown to increase the digestibility of poorly digested diets to a much greater extent. By targeting specific anti-nutrients in certain feed ingredients, feed enzymes allow especially pigs and poultry to extract more nutrients from the feed and so improve feed efficiency. Enzymes are most commonly used when the dietary ingredients contain relatively higher amounts of fiber. The classification of enzymes is usually according to the substrates they act upon and the classification can be enzymes that break down fiber, proteins, starch and phytate. Appropriate use of exogenous enzymes in feeds requires strategic reductions in dietary energy and nutrient content, as well as careful choice of feed ingredients to capture economic benefits of the various enzymes. The efficacy of enzymes will vary depending on ingredients because nutrient and energy release caused by enzyme supplementation will depend on the structure of the feedstuff itself. It is important to continue the effort to understand the use and limitations of matrix values of enzymes, which, if inappropriately applied, will result in depressed performance because of inadequacy of diets or will lead to wastage of resources. Key words: Carbohydrate, monogastric, feed enzymes, phytase, nutrient utilization.

The huge livestock resources of the country could not be used to its potential due to lack of good-quality feed throughout the year. Consequently, finding alternative feed supplements for livestock is an important step to sustain livestock production in the country. Ficus thonningii leaf is one of the potential feed resources for ruminants in the area. The experiment was conducted with the objective of evaluating the nutrient intake, digestibility and growth performance of local lambs fed natural pasture hay (NPH)-based diet supplemented with graded levels of Ficus thonningii dried leaves (FTL) and determining of the optimum level for replacing of concentrate mixture (CM). Twenty intact male yearling Washera lambs with initial body weight of 17.06 + 1.43 (mean + SE) kg were used in experiment. The experiment was conducted using randomized complete block design having four replications with five dietary treatments. The treatments were T1 = NPH + 0 g FTL +215 g CM; T2 = NPH + 112.5 g FTL +161.25 gCM; T3 = NPH + 225 g FTL +107.5 g CM; T4 = NPH + 337.5 g FTL + 53.75 g CM; and T5 = NPH + 450 g FTL +0 g CM. Data were analyzed using the general linear model procedures of SAS (version 9.3; 2002). The results showed that FTL are a good source of crude protein (CP) (126.9 g/KgDM) and fibers (377–426 g/Kg DM). Results also showed that supplementation of higher-level FTL significantly (P < 0.001) increased total DM, OM and fibers intake (P < 0.001), but no significant difference (P > 0.05) observed in CP and ME intakes among treatments. Increasing level of FTL supplementation, however, reduced significantly (P < 0.001) the digestibility coefficient of all nutrients. In terms of ADG, nonsignificant (P > 0.05) differences were observed in lambs assigned up to 75% replacement of CM. The lowest performance was observed in sole FTL supplementation (T5), despite increased nutrients intake. It was concluded that indigenous fodder tree Ficus thonningii leaves could serve as alternative CP supplement in NPH-based feeding of Washera sheep and can be used to replace CM up to 75% to improve performance.

The experiment was conducted using twenty-five Farta sheep to investigate the response of supplementing dried Sesbania sesban leaves (SSL) on feed intake, digestibility, growth performance and carcass characteristics of Farta sheep fed urea-treated rice straw. Twenty-five male Farta sheep with initial body weight of 18.9 ± 1.7 kg (mean ± SD) were used in randomized complete block design with five replications. The treatments were 0 g Sesbania sesban leaves (SSL) (control T₁), 100 g SSL (T₂), 200 g SSL (T₃), 300 g SSL (T₄) and 400 g SSL (T₅). The experiment lasted 90 days of growth and 7 days of digestibility period. All experimental sheep were given urea-treated rice straw ad libitum as basal diet. Chemical composition of diets and refusals, feed intake, digestibility of dry matter and nutrients, carcass yield and quality were recorded. All collected data were analyzed using general linear model (GLM) procedure of SAS version 9.1.3. Means were separated using Duncan’s multiple-range test. Correlations among nutrient intakes, weight gain and digestibility of nutrients were analyzed using Pearson linear correlation test. Results showed that supplementation of SSL significantly increased (P < 0.001) total dry matter, crude protein and organic matter intakes. Supplementation of SSL improved the digestibility of dry matter, organic matter (P < 0.05), crude protein (P < 0.01). Final body weight (P < 0.01), average daily gain and feed conversion efficiency (P < 0.001) for T₅ were higher for supplement groups, while sheep fed sole UTRS (T₁) lost body weight. Slaughter weight (P < 0.01), empty body weight (P < 0.01) and hot carcass weight (P < 0.001) increase with increase in the level of supplementation. Dressing percentage on slaughter BW basis and EBW basis was higher (P < 0.05) for T₅ than control. The partial budge analysis result indicated that sheep fed UTRS alone had the lowest net return (− 92.22 ETB), while sheep supplemented with 400 g SSL (T₅) had better net return (144.6 ETB) with marginal rate (1.7) compared to the other supplemented treatments. From the study it could be concluded that SSL could serve as alternative CP supplement in urea-treated-based crop residues feeding of growing Farta sheep to improve the biological performance and economic feasibility in the study area.