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Crop and livestock production in the Guinea savanna zone of northern Ghana has been declining over the past years as a result of increasing pressure on land. To sustain soil productivity, pigeon pea(Cajanus cajan), a leguminous perennial crop was evaluated for its potential as a short duration fallow crop for fodder and grain, and maize (Zea mays)production. It involved comparing a natural fallow (i.e., control) and four improved fallows of pigeon pea pruned annually at 30 cm, 60 cm and 90 cm from the ground, and unpruned pigeon pea over a two-year period. After this time, the land was cleared manually and planted to maize. The highest mean annual biomass of pigeon pea over the two-year period of 6.1 t ha−1 dry matter (DM) was obtained by pruning at 60 cm. The highest leaf litter production and pigeon pea seed yield was obtained from the no pruning treatment. The mean maize grain yield from the improved fallow (3.02 t ha−1) in the first year after clearing was significantly (P < 0.05) greater than that of the natural fallow (1.54 t ha−1). Considering the biomass of pigeon pea from pruning, pigeon pea seed yield and maize grain yield after the pigeon pea, pruning pigeon pea at 60 cm is the most promising regime for crop-livestock production systems. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
2.
The study was conducted with the view to determine the impact of replacing fishmeal with black soldier fly larval meal (BSFLM) on growing guinea fowls. BSFLM replaced fishmeal (3% in the control diet) in the ratios of 0, 20, 40, 60, 80, and 100% to produce six dietary treatments, which were iso-caloric and iso-nitrogenous. Two hundred and forty-eight-week old guinea fowls with mean live weight of 273.2?±?10.9 g were tagged, weighted, and randomly assigned to 24 (6?×?4) floor pens; each pen was treated as a replicate. Feed and water were provided ad libitum during the entire period, which lasted 10 weeks. Feed consumption differed among the treatment groups (P?=?0.0072) with the 100% fishmeal diets recording the lowest. Daily gain was significantly (P?=?0.009) higher for birds fed high BSFLM diets compared to the control (100% fishmeal diet). The inclusion of BSFLM in the diets elicited positive linear effect on weight gains of the guinea fowls (R2?=?0.91) with increasing concentration resulting in higher live weight gains. The feed conversion ratio (FCR) also differed between treatments (P?<?0.05) but similar for the 100% fishmeal (control) and 100% BSFLM diets. Organ and haematopoitic integrity were equally assured regardless of levels of the protein sources fed to the birds. Generally, meats from birds fed 60 to 100% BSFLM and from hens were more acceptable. A study to evaluate the economics of utilising BSFLM in guinea fowl production is recommended.  相似文献   
3.

Feed shortage in urban and peri-urban areas has triggered the emergence of feed markets in Northern Ghana. These markets were surveyed at three locations (Tamale, Bolgatanga, and Wa markets) to determine types and prices of feedstuffs sold across seasons; early dry (November–January), late dry (February–April), early wet (May–July), and main wet (August–October). Semi–structured questionnaire was used for data collection. Three samples of each feed type in the markets were bought from three different sellers per market in each season. The samples were oven dried to constant weight and price/kg DM of each feed determined. The total respondents were 169. Out of this number, 41% were feed sellers, 46% buyers, and 13% retailers. The feedstuffs found were crop residues (groundnut haulm and cowpea haulm), agro-industrial by-products (bran of maize, rice, and sorghum), fresh grasses (Rotteboellia cochinchinensis), and local browses (Ficus sp. and Pterocarpus erinaceous). Prices of feeds differed (P < 0.05) among markets and were higher in Bolgatanga than Tamale and Wa markets. Prices of cereal bran were not different (P > 0.05) in all seasons but that of crop residues were higher (P < 05) in early to late dry season than the wet season. Majority (90%) of respondents opined that the feed market will expand due to increasing number of livestock population in the peri-urban areas.

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4.
Pigeon pea is cultivated by most smallholder crop–livestock farmers mainly as a border crop. It is quite often sparsely intercropped in cereal‐based cropping systems in the subhumid zone of Ghana. Management of pigeon pea and its biomass is a promising means of improving many abandoned arable fields but has not been consciously undertaken. The objective of this trial was to explore the use of pigeon pea and the management of its pruned biomass as part of an improved fallow for crop–livestock farming. Three pigeon‐pea management options and a natural fallow (two‐year fallow period) were compared in terms of maize grain yield and changes in soil organic carbon, total nitrogen and cation exchange capacity. Pigeon pea grain yield ranged between 615 and 678 kg ha−1 and 527 and 573 kg ha−1 in the first and second year of fallow, respectively. In the first year after fallow, maize grain yield ranged between 0·43 and 2·39 t ha−1 and was significantly influenced by the fallow system. There was a marked decrease in maize grain on the pigeon pea fallow plots in the second year, ranging between 50 and 38·6 per cent in Kumayili and between 42·6 and 17·6 per cent in Tingoli. After the two‐year fallow period, increase of soil organic carbon on the pigeon pea fallow plot compared with the natural fallow plot was 30·5 per cent, and there was an improvement of total nitrogen (48·5 per cent) and CEC (17·8 per cent). Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
5.
In order to assess the impact of larval meal on guinea fowl, six iso-caloric and iso-nitrogenous diets were fed to day-old-keets ad libitum till 8 weeks of age. Water was also freely provided. The fishmeal (FM) component of the experimental diets was replaced with black soldier fly larval meal (BSFLM) in the following percentage ratios of 0–100%. Results showed that body weight gain significantly (P < 0.05) increased in all the BSFLM treatment groups compared to the control group. The final body weight of the birds at age 8 weeks differed significantly (P < 0.001). Dry matter intake varied (P < 0.001) slightly among the birds but never affected (P > 0.05) ME intake and faecal output as well as weight changes of the keets. Digestibility of dry matter and energy were not affected (P > 0.05) by the differences in diet. Organ and haematopoietic integrity were assured regardless of the protein types used as well as levels of inclusion. The results suggest that the replacement of fishmeal with BSFLM in so far as the economics of production is concerned could result in reduced feed cost for starter guinea keet judging from diets that contained 60–100% BSFLM.  相似文献   
6.
Effects of genetic and environmental factors on pre-weaning and post-weaning growth were studied in West African crossbred sheep. Effects of lamb genotype (7/8 Sahelian–1/8 Djallonké, 3/4 Sahelian–1/4 Djallonké and 1/2 Sahelian–1/2 Djallonké; hereafter denoted 7/8Sa, 3/4Sa and 1/2Sa, respectively), parity, type of birth, sex of lamb and year-season of lambing on birth weight, weaning weight, 8-month weight and pre- and post-weaning growth rates were determined. At birth 7/8Sa and 3/4Sa lambs were heavier (p<0.01) than 1/2Sa lambs. Lambs born to first-parity ewes were lighter (p<0.01) at birth than lambs of older ewes. At weaning and 8 months of age, lambs born to fourth-parity ewes were heavier (p<0.05) than those born to ewes of the other parities. Parity did not have any significant effects on pre-weaning growth rate. Lambs born in the rainy season of 2001 were significantly heavier at birth and at 8 months of age than those born in the dry season of 2001/02, but there was no difference between the two groups at weaning. Pre-weaning growth rate was significantly faster in lambs born in the dry season of 2001/02 but the reverse was true for post-weaning growth rate.  相似文献   
7.
An 8-year field study documented the impact of tillage, crop rotations, and crop residue management on agronomic and soil parameters at Brookings, South Dakota. The greatest annual proportion of above-ground biomass phosphorus (P) removed was from the grain (78–87% of total) although crop residue removed some P as well. Greater above-ground total biomass P (grain P + crop residue P) was removed from corn than from soybean and spring wheat crops mainly due to the greater corn grain biomass harvested. Cumulative above-ground biomass P removal was greatest for the corn-soybean rotation (214 kg P ha?1), while it was lowest for the soybean-wheat rotation (157 kg P ha?1). Tillage treatments within crop rotation or residue management treatments did not influence annual or cumulative P removal rates. Olsen extractable soil orthophosphate-P levels declined consistently through time from a mean of 40 µg g?1 (2004) to 26 µg g?1 (2011). Biomass P removal was calculated to be 15.7 ha?1 yr?1 to decrease Olsen extractable soil orthophosphate-P levels by 1 µg g?1 yr?1 over 8 years of the study.  相似文献   
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