Bioconversion of poultry manure and vegetable waste mixes by Hermetia illucens (Diptera: Stratiomyidae)

Development time, survival and final nutrient content of Hermetia illucens L. larvae depends on the substrates in which they develop. Mixing different waste types together can increase the performance and survival of the larvae, as well as their waste reduction. The main objective of this study was to evaluate the effect of different ratios of mixed fruit and vegetable waste with poultry manure on larval development time, size, biomass production, survival, bioconversion and waste reduction. Freshly hatched neonates (90 mg; approx. 6000 individuals) were placed on 12 kg of a mixture of fruit and vegetable waste and fresh, unprocessed poultry manure and held at 28 ± 0.5°C. Inclusion of fruit and vegetable waste varied from 0% to 100% in 10% increments. Initial temperature of the substrate was also measured. The individual mass of larvae increased significantly as more fruit and vegetable waste was included, from less than 81.3 ± 6.6 mg on poultry manure only to an average size of 211.6 ± 6.0 mg at 100% fruit and vegetable waste. After approximately 60% inclusion of fruit and vegetable waste the performance and survival of the larvae increased significantly while development time was reduced. A combination of high fruit and vegetable waste and low initial temperatures resulted in lower development time overall. The mixing of wastes can be applied in industry to further the goals of waste reduction and biomass production while incorporating low-quality wastes like poultry manure.     

Nutritional quality and digestibility of sorghum-broiler litter silages

Broiler litter and sorghum forage were ensiled in the proportions of 0:100, 25:75, 35:65 and 45:55 (wet basis), respectively. Samples of initial mixtures showed the presence of total (0.01–1.20×10⁶) and fecal (0.001–3.190×10⁴) colony forming units (CFU). Salmonellae, Shigella and Proteus were also present. Ensiling was effective in complete elimination of all the pathogens. Dry matter (DM), crude protein (CP) and ash contents were increased linearly (P<0.01) with the increase of broiler litter in the silages (35–57.5%; 6.4–14.8% and 3.2–9.0%; DM basis, respectively). Water soluble carbohydrate (WSC) for initial mixtures were 7.7%, 6.7%, 6.2% and 5.9%; DM basis, respectively. Ensiling decreased the pH and WSC for all the silages and the decrease was higher for sorghum ensiled alone than for sorghum ensiled with broiler litter. Lactic acid concentration in the silages increased linearly (P<0.01) with the increase of broiler litter. The nutritive value of the silages was evaluated in a digestion trial with 24 wethers. The apparent digestibilities of DM, OM and CP for the animals fed sorghum silage alone were, 49.6%, 51.6% and 49.7%, respectively. However, digestibilities of all the components were higher (P<0.01) for the animals fed silages containing broiler litter. Among the litter containing diets, the digestibilities of all the components showed a quadratic effect (P<0.01), increasing for silages containing 25% and 35% broiler litter and decreasing, when the level of litter increased from 35% to 45%. The results indicated that broiler litter could be used up to 35% in a ruminant's diet as a source of N without any adverse effect on health of the animals. Ensiling appeared to be a feasible and effective method for eliminating the pathogens present in broiler litter and improving its nutritive value.     

Effective bioconversion of farmed chicken products by black soldier fly larvae at commercially relevant growth temperatures

Global population growth and an increasing demand for meat has driven the intensification of livestock production. On poultry farms, the accumulation of waste such as faeces, carcasses and unsellable eggs creates environmental and health hazards that need to be mitigated. The larvae of the black soldier fly (Hermetia illucens; BSFL) offer a potential solution to the problems of waste management on poultry farms. BSFL consume large quantities of organic waste and convert it into larval biomass, which can then be processed for use as livestock feeds or biofuels. This makes BSFL an ideal candidate for value-added waste management on chicken farms. Here, we examined the development and nutrient profile of BSFL given five different diet treatments: poultry feed (control), chicken meat, chicken egg, chicken manure and a mixture of equal parts chicken meat, egg and manure. Chicken meat, egg and mixed diets were all found to be suitable feedstocks for BSFL, but the manure-only treatment was associated with a high failure rate of larval development. Mixing manure with other poultry waste streams ameliorated the negative impacts of manure on BSFL. Larvae reared on chicken meat, egg and the mixed diet had equal or higher mean crude protein (CP) (39.9%, 33.8% and 31.5%, respectively) and crude lipid (CL) contents (30.1%, 29.00% and 28.7%, respectively), compared with BSFL reared exclusively on chicken feed (CP: 30.9%, CL: 23.8%), demonstrating the suitability of these waste-stream diets for the potential animal feed quality of the BSFL. We discuss how BSFL bioconversion could be implemented to address environment management issues on poultry farms.     

The utilization of alkali-treated melon husk by broilers

The effects of alkali treatment on chemical constituents of melon husk (MH) and performance characteristics of broilers fed alkali-treated MH (ATMH) diets were investigated. The chemical analysis showed that alkali treatment increased the ash content of MH (from 15.70% to 16.86%) and reduced the crude fibre content (from 29.00% to 14.00%). Result of feed intake was superior on 30% alkali diet with a value of 100.14 g/bird/day. Body weight gain decreased with increase in the level of ATMH in the diet. Highest dressing percentage of 66.33% and best meat/bone ratio of 2.57 were obtained on 10% and 20% alkali diets, respectively. Dietary treatments had significant effect (P < 0.05) on gizzard weight. Up to 20% of maize can be replaced with ATMH in broiler diets to produce good quality poultry carcases and chicken meat with favourable shelf life.     

Characterization of Phosphorus in Animal Manures Collected from Three (Dairy,Swine, and Broiler) Farms in China

In order to identify the phosphorus species and concentration in animal manure, we comparatively characterized phosphorus in dairy manure, swine manure, and broiler litter, using a sequential procedure, a simplified two-step procedure (NaHCO₃/NaOH+EDTA), and a solution Phosphorus-31 Nuclear Magnetic Resonance (³¹P-NMR) spectroscopy procedure. In the sequential procedure, deionized water extracted 39, 22, and 32%; NaHCO₃ extracted 48, 26, and 37%; NaOH extracted 8, 9, and 13.8%; and HCl extracted 3, 42.8, and 17% of the total phosphorus in dairy manure, swine manure and broiler litter, respectively. Total phosphorus extracted by the NaHCO₃/NaOH+EDTA procedure was 7.5, 32.4, and 15.8 g P kg⁻¹ for dairy manure, swine manure, and broiler litter, respectively. The solution ³¹P-NMR procedure detected that 9, 34, and 29% of total phosphorus was phytic acid in dairy manure, swine manure, and broiler litter, respectively. These results show that phosphorus forms, availability, and quantities differ between animal manures, which provides valuable information for P characterization of animal manures in China.     

Nutritive value of deep stacked and ensiled broiler litter for sheep

Broiler litter was deep stacked and ensiled with water to achieved 40% moisture before being added, with or without 5% sugarcane molasses or with rumen contents, to a basal diet. The influence of stacking and ensiling of broiler litter on the numbers of Salmonella, Shigella, Proteus and total number of colony forming units (CFU) was investigated. Nutritive value of broiler litter processed by deep stacking and ensiling was evaluated in a digestibility trial. The experiment was conducted with 30 wethers allotted to five diets. A basal diet (20% corn grain, 23% wheat bran, 37% cotton seed cake, 18% wheat straw and 2% dicalcium phosphate) was given alone (1) or with broiler litter processed by deep stacking (2), ensiling (3), ensiling with 5% added molasses (4), or ensiling with rumen contents (1:1, wet basis) (5). For Diets 2–5, the ratio of basal diet to silage was 1:1, dry basis. For the digestion trial, diets were given at 20 g dry matter (DM) kg⁻¹ body weight per day. Initial samples of broiler litter showed 2.5 × 10⁸ CFU and Salmonella, Shigella and Proteus were present. The processes of deep stacking and ensiling were equally effective in achieving a complete elimination of all the pathogens. Apparent digestibilities of organic matter (OM) and crude protein (CP) (559.1 g kg⁻¹ and 608.7 g kg⁻¹ DM) were lower (P < 0.05) for diet 2 (deep stacked litter) than for the other waste-containing diets (OM: 578.7 g kg⁻¹, 582.9 g kg⁻¹, 594.1 g kg⁻¹; CP: 688.6 g kg⁻¹, 675.8 g kg⁻¹, 709.0 g kg⁻¹ DM, for Diets 3, 4 and 5, respectively). Among the waste-containing diets, cellulose digestibility (398.7 g kg⁻¹ DM) was higher (P < 0.05) for Diet 5 (ensiled litter-rumen contents). The results indicate that deep stacking and ensiling are equally feasible and effective for eliminating the pathogens and processed broiler litter can be incorporated in the diet of ruminants at levels of up to 50% without any adverse effect on the health of the animals.     

Human urine is an excellent liquid waste for the culture of fish food organism, Moina micrura

With a view to converting human urine into bio-wealth in the form of zooplankton, the nutrient potentials of liquid wastes (0.11 mL L⁻¹)—(i) human urine (♂), (ii) cow urine, (iii) human–cow mixed urine or some solid wastes (0.11 g L⁻¹): (iv) vermi-compost, (v) cow dung, (vi) poultry droppings and (vii) mixed wastes (vermi-cow-poultry)—were evaluated for the mass culture of zooplankton Moina micrura in 24 outdoor tanks (4500 L) in triplicate treatments using life table as indicator during the period of October–December, 2005. Neonates of Moina micrura held in the treatment with human urine started reproduction at least 4 days earlier than other solid wastes tested. Total number of Moina micrura enumerated in the culture tank, related with offspring production per life span, was maximum in case of human urine treatment, followed by human–cow mixed urine, cow urine, vermin-compost, poultry droppings, mixed wastes (vermin–cow–poultry), cow dung and control treatments. The relationship between the total offspring production per female per life span and the nitrogen content of water in different treatments implied that human urine was an excellent liquid waste that can be used for the mass production of zooplankton Moina micrura required for larval and post larval rearing of commercial fishes.     

Determinations of feed–milk–manure relationships on grazing-based dairy farms

Feed conversion into milk, nutrient excretion in manure and subsequent environment impacts of manure management are highly influenced by the diets that farmers feed their lactating cows (Bos taurus). On confinement-based dairy farms, determinations of diet composition are relatively straightforward because the types, amounts and nutrients contained in stored feeds are often well known. However, on grazing-based dairy farms, diet composition is more difficult to determine because forage intake during grazing must be estimated. The objectives of this study were to determine relationships between (1) feed N intake (NI), milk production, milk urea N (MUN), feed N use efficiency (FNUE) and excreted manure N (ExN); and (2) between feed P intake (PI), dung P concentrations (g/kg dry matter (DM)) and excreted manure P (ExP) for grazing-based lactating cows having a very wide range of diets and milk production. An additional objective was to evaluate how well these relationships compare with similar relationships based on more direct measurement of feed–milk–manure on confinement-based dairy farms. Four dairy farms located in southeastern Australia were visited during autumn and spring, and data were collected on feed, milk and dung of 18 cows on each farm. Estimated dry matter intake (DMI) from pasture comprised 12% to 75% of total diet DMI, and the crude protein (CP) concentrations in the total diets ranged from 167 to 248 g/kg. During spring, as diet CP increased FNUE declined. Total diet DMI and NI provided the best predictors of ExN, and PI provided the most accurate prediction of ExP. These results indicated accuracy in the study's indirect estimates of pasture DMI. Likely due to high levels and great variability in dietary CP and P concentrations associated with use of diet supplements, MUN did not appear to be a good indicator of dietary CP, and P in dung was not a good indicator of dietary P.     

The effects of supplemental levels of inorganic zinc,manganese and copper on growth performance in commercial broilers

Commercial broiler premixes provide trace minerals (TMs) such as Zinc (Zn), Manganese (Mn) and Copper (Cu) above the birds' requirements to maximise broiler performance. High inclusion levels of TM and their low absorption in the broiler's gastrointestinal tract have led to increased TM levels in their litter, raising concerns about TM's accumulation in the environment from poultry litter. A 35-day broiler trial was conducted at a broiler facility with 2 880-day-old Cobb 500 broiler males. The objective was to evaluate whether decreasing inorganic Zn, Mn and Cu levels in broiler diets would have a negative effect on broiler growth parameters such as BW, average daily gain, cumulative feed intake (FI) and feed conversion ratio (FCR). Consequently, these minerals were supplemented at 100%, 50%, 25%, and 0% of the Cobb standards. No significant difference in FI and FCR was observed between the treatments for the first 21 days, and there were no significant differences in BW between the positive control, negative control (NC), and 50% of Cobb recommended levels at day 35. However, BW for the NC was significantly higher than the 25% level. These results show that reducing TM levels in broiler diets below commercially recommended levels had no negative effect on broiler performance, with the subsequent economic benefits for producers.     

Utilization of processed pig hair in poultry diets

A commerically prepared sample of pig hair was evaluated in semi-purified and practical diets as a source of essential amino acids for poultry. Amino acid (total) supplementation of pig-hair protein in semi-purified diets indicated that the amino acids were utilized by poultry and that satisfactory performance was obtained when the protein was supplemented with the essential amino acids that analysis had shown to be lacking. The performance of broiler chickens fed on diets containing up to 6% pig hair, and of growing pullets fed on diets containing up to 9% of this material, suggests that properly processed pig hair can be used in rations along with other keratin proteins.     

Feed intake and digestion in the maned wolf (Chrysocyon brachyurus): Consequences for dietary management

Captive maned wolves (Chrysocyon brachyurus) often consume diets high in prey and meat items even though they are omnivorous in the wild. These soft, high protein diets may exacerbate conditions of gingivitis and cystinuria in this species. Feed intakes were monitored in wolves provided with prey and meat-based diets (3 periods) and subsequently with extruded dog chows and small amounts of prey (2 periods). Digestibilities of each type of diet were measured with the indigestible marker chromic oxide. Dry matter intakes were similar between diets (374–584 g · 30 kg^?1 · d^?1), even though dietary protein content was reduced from 44% to 29% of dry matter. Digestibility of dry matter was unaltered by these dietary changes (77% of high prey diet vs. 73% of chow diet), but fecal consistency changed to softer stools at lower intakes of prey. Estimated metabolizable energy intakes of wolves (501–674 kJ · kg^?0.75 · d^?1) were similar to the maintenance requirement for domestic dogs (525 kJ · kg^?0.75 · d^?1), suggesting a similar energy requirement for maintenance of the wolves. The metabolizable energy derived from protein in the high prey diets was 37%, whereas that of the chow diets was only 27%. These levels exceed estimates of protein requirements for maintenance (4.3–21.8%) and growth (11.5–20.3%) in domestic dogs and may thus exceed those of the wolves. Dietary management of maned wolves should minimize excess protein intake by limiting prey consumption and acclimating animals to extruded diets for domestic dogs. Further research is required to formulate diets for long-term management of cystinuria in maned wolves. © 1994 Wiley-Liss, Inc.     

Effects of expeller pressed camelina meal and/or canola meal on digestibility, performance and fatty acid composition of broiler chickens fed wheat-soybean meal-based diets

This experiment was conducted to compare the effects of graded levels of camelina meal and/or canola meal on digestibility, performance and fatty acid composition of broiler chickens. A total of 180-day-old male broiler chicks were randomly assigned to one of the six treatments. The control diet was based on wheat and soybean meal and contained 15% canola meal. The experimental diets contained 3%, 6%, 9%, 12% or 15% camelina meal added at the expense of canola meal. Chromic oxide (0.35%) was added to all diets as a digestibility marker. On the morning of day 22, birds were killed by cervical dislocation and their abdominal fat pad was obtained. The apparent total tract digestibility of dry matter and energy as well as nitrogen retention all declined linearly (p?相似文献   

Influence of organic and inorganic sources of nutrients on the functional diversity of microbial communities in the vegetable cropping system of the Indo-Gangetic plains

The aim of the present study was to assess the effects of different organic and inorganic fertilizers on the functional diversity of soil microbial community under a vegetable production system. The Biolog^® Eco-plate technique and indices, such as average well-colour development (AWCD), McIntosh and Shannon diversity were employed to study the diversity of soil microorganisms. The AWCD, i.e. overall utilization of carbon sources, suggested that different organic treatments had a significant impact on the metabolic activity of soil microorganisms. After 120 h, the highest AWCD values were observed in poultry manure (2.5 t·ha^?1) + vermicompost (3.5 t·ha^?1) (0.63) and farm yard manure (FYM) (10 t·ha^?1) + vermicompost (3.5 t·ha^?1) (0.61). After 72 h, the highest value of the McIntosh diversity index was recorded in poultry manure (2.5 t·ha^?1) + vermicompost (3.5 t·ha^?1) (3.87), followed by poultry manure (2.5 t·ha^?1) + vermicompost (3.5 t·ha^?1) + biofertilizers (Azotobacter 500 g·ha^?1 applied as seed treatment) (3.12). In the case of the Shannon diversity index, the highest values were noticed in organic treatments; however, there was no significant differences between organic and inorganic treatments. Biplot analysis showed a clear differentiation of organic treatments from the inorganic control. The amino acids, phenolics and polymer utilizing microorganisms were dominant in organic treatments. Inorganic control recorded the lowest values of the microbial diversity indices. Through this study, we have identified the best combination of organic nutrients, i.e. poultry manure (2.5 t·ha^?1) + vermicompost (3.5 t·ha^?1) for the stimulation of metabolically active soil microbial communities.     

Nutritive value of rumen contents for monogastric animals

Rumen contents were investigated as a possible feed for farm animals. Although their composition varied to some extent, an average sample contained 21.8% crude protein, 30.3% crude fibre, 6.1% fat and 11.5% ash in the dry matter. Of total crude protein, 73.4% was amino acids. The raw rumen material was dried using the “organic carrier method” by previous mixing with maize meal (3 parts raw rumen contents/1 part maize meal). The product, RM meal (12.5% crude protein, 10.8% crude fibre, 5% fat, 4.9% ash), was used for feeding broiler chicks.The nutritive qualities of dried rumen contents (DRC) were assessed by biological tests on rats. Two levels of DRC (10% and 24%) were included in diets containing blood meal as a protein source and maize (Experiment I). The lower level of DRC (10%) did not reduce the growth rate of young rats (2.4 g/day), but the food consumption was increased. The total body composition of the rats was not changed (55.3% crude protein, 34.1% fat, 9.6% ash). The higher concentration of DRC decreased the growth rates markedly, as well as the apparent digestibility of dry matter and protein, and changed the body composition of rats.The apparent digestibility by rats of rumen protein in a semi-synthetic diet containing 50% DRC (Experiment II) was 44.6% and of dry matter, 56%.The RM meal was given to broiler chicks (0–8 weeks of age) as 23% or 60% of the diet which also contained soya bean meal, blood meal and sunflower meal as protein supplements (Experiment III). The chicks consumed all diets readily. The diet containing 23% RM meal (corresponding to 6.4% DRC) supported a better performance than the control diet. The larger amount of RM meal (corresponding to 17% DRC) reduced the final body weights of chicks.     

A Comparison of BOX-PCR and Pulsed-Field Gel Electrophoresis to Determine Genetic Relatedness of Enterococci from Different Environments

Genetic relatedness of enterococci from poultry litter to enterococci from nearby surface water and groundwater in the Lower Fraser Valley regions of British Columbia, Canada was determined. A new automated BOX-PCR and Pulsed-Field Gel Electrophoresis (PFGE) were used to subtype enterococcal isolates from broiler and layer litter and surface and groundwater. All surface water samples (n = 12) were positive for enterococci, as were 11% (3/28) of groundwater samples. Enterococcus faecium (n = 90) was isolated from all sources, while Enterococcus faecalis (n = 59) was isolated from all sources except layer litter. The majority of E. faecalis originated from broiler litter (28/59; 47.5%) while the majority of E. faecium were isolated from layer litter (29/90; 32.2%). E. faecalis grouped primarily by source using BOX-PCR. Isolates from water samples were dispersed more frequently among PFGE groups containing isolates from poultry litter. E. faecium strains were genetically diverse as overall clustering was independent of source by both molecular methods. Subgroups of E. faecium isolates based upon source (layer litter) were present in BOX-PCR groups. Three individual E. faecalis groups and two individual E. faecium groups were 100% similar using BOX-PCR; only one instance of 100% similarity among isolates using PFGE was observed. Although enterococci from litter and water sources were grouped together using BOX-PCR and PFGE, isolates originating from water could not be definitively identified as originating from poultry litter. Automation of BOX-PCR amplicon separation and visualization increased the reproducibility and standardization of subtyping using this procedure.     

Evaluation of broiler litter with reference to the microbial composition as assessed by using 16S rRNA and functional gene markers

Very little is known about the microbial composition of animal bedding wastes, including poultry litter, and what is known has been deduced from standard culture methods, by which some fastidious organisms that exist in the environment may not be detected. We evaluated the bacterial composition of poultry litter by using a combination of culture and molecular detection. Total aerobic bacteria in poultry litter were detected by culture at 10(9) CFU/g of material. Enteric bacteria such as Enterococcus spp. and coliforms composed 0.1 and 0.01%, respectively, of the total aerobic cultivatable bacteria in poultry litter; no Salmonella strains were detected by culture. In order to characterize the most abundant bacterial groups, we sequenced 16S ribosomal DNA (rDNA) genes amplified by PCR with microbial community DNA isolated from poultry litter as the template. From the 16S rDNA library, 31 genera were identified. Twelve families or groups were identified with lactobacilli and Salinococcus spp. forming the most abundant groups. In fact, 82% of the total sequences were identified as gram-positive bacteria with 62% of total belonging to low G+C gram-positive groups. In addition to detection of 16S rDNA sequences associated with the expected fecal bacteria present in manure, we detected many bacterial sequences for organisms, such as Globicatella sulfidofaciens, Corynebacterium ammoniagenes, Corynebacterium urealyticum, Clostridium aminovalericum, Arthrobacter sp., and Denitrobacter permanens, that may be involved in the degradation of wood and cycling of nitrogen and sulfur. Several sequences were identified in the library for bacteria associated with disease in humans and poultry such as clostridia, staphylococci, and Bordetella spp. However, specific PCR targeting other human and veterinary pathogens did not detect the presence of Salmonella, pathogenic Escherichia coli, Campylobacter spp., Yersinia spp., Listeria spp., or toxigenic staphylococci. PCR and DNA hybridization revealed the presence of class 1 integrons with gene cassettes that specify resistance to aminoglycosides and chloramphenicol. Only from understanding the microbial community of animal wastes such as poultry litter can we manage animal disease and limit the impact of animal waste on the environment and human and animal health.     

Evaluation of velvet bean meal as an alternative protein ingredient for poultry feed

The effect of certain simple and cost-effective processing methods on the nutritional and anti-nutritional properties of seed materials of an under-utilized food legume, Mucuna pruriens (L.) DC. var. utilis (Wall. ex Wight) Baker ex Burck (velvet bean, VB), collected from Valanadu, Kerala, India was analyzed in experiment 1. The raw VB seeds were found to contain appreciable levels of crude protein (263.2 g/kg dry matter (DM)); ether extract (79.6 g/kg DM); crude fiber (95.8 g/kg DM) and ash content (38.4 g/kg DM). Among the different treatments used, soaking in sodium bicarbonate solution + autoclaving was more effective in reducing maximum levels of various anti-nutritional compounds of VB seeds. Furthermore, in experiment 2, the effect of inclusion of different levels of velvet bean meal (VBM; subjected to soaking in sodium bicarbonate solution + autoclaving) as an alternative protein source in poultry feed on the growth performance of commercial-type broiler birds was investigated. The results indicate that the inclusion of VBM up to the 40% level exhibited better growth performance of the broiler birds such as feed intake, body weight gain, feed conversion ratio and protein efficiency ratio in both the starter and finisher phases.     

Faecal near-IR spectroscopy to determine the nutritional value of diets consumed by beef cattle in east Mediterranean rangelands

Rapid assessment of the nutritional quality of diets ingested by grazing animals is pivotal for successful cow–calf management in east Mediterranean rangelands, which receive unpredictable rainfall and are subject to hot-spells. Clipped vegetation samples are seldom representative of diets consumed, as cows locate and graze selectively. In contrast, faeces are easily sampled and their near-IR spectra contain information about nutrients and their utilization. However, a pre-requisite for successful faecal near-infrared reflectance spectroscopy (FNIRS) is that the calibration database encompass the spectral variability of samples to be analyzed. Using confined beef cows in Northern and Southern Israel, we calibrated prediction equations based on individual pairs of known dietary attributes and the NIR spectra of associated faeces (n=125). Diets were composed of fresh-cut green fodder of monocots (wheat and barley), dicots (safflower and garden pea) and natural pasture collected at various phenological states over 2 consecutive years, and, optionally, supplements of barley grain and dried poultry litter. A total of 48 additional pairs of faeces and diets sourced from cows fed six complete mixed rations covering a wide range of energy and CP concentrations. Precision (linearity of calibration, R²cal, and of cross-validation, R²cv) and accuracy (standard error of cross-validation, SEcv) were criteria for calibration quality. The calibrations for dietary ash, CP, NDF and in vitro dry matter digestibility yielded R²cal values >0.87, R²cv of 0.81 to 0.89 and SEcv values of 16, 13, 39 and 31 g/kg dry matter, respectively. Equations for nutrient intake were of low quality, with the exception of CP. Evaluation of FNIRS predictions was carried out with grazing animals supplemented or not with poultry litter, and implementation of the method in one herd over 2 years is presented. The potential usefulness of equations was also established by calculating the Mahalanobis (H) distance to the spectral centroid of a calibration population of 796 faecal samples collected throughout 2 years in four herds. Seasonal trends in pasture quality and responses to management practices were identified adequately and H<3.0 for 98% of faecal samples collected. We conclude that the development of FNIRS equations with confined animals is not only unexpensive and ethically acceptable, but their predictions are also sufficiently accurate to monitor dietary composition (but not intake) of beef cattle in east Mediterranean rangelands.     

Meta-analysis of phosphorus utilisation by broilers receiving corn-soyabean meal diets: influence of dietary calcium and microbial phytase

Pollution relative to phosphorus excretion in poultry manure as well as the soaring prices of phosphate, a non-renewable resource, remain of major importance. Thus, a good understanding of bird response regarding dietary phosphorus (P) is a prerequisite to optimise the utilisation of this essential element in broiler diets. A database built from 15 experiments with 203 treatments was used to predict the response of 21-day-old broilers to dietary non-phytate P (NPP), taking into account the main factors of variation, calcium (Ca) and microbial phytase derived from Aspergillus niger, in terms of average daily feed intake (ADFI), average daily gain (ADG), gain to feed (G:F) and tibia ash concentration. All criteria evolve linearly (P < 0.001) and quadratically (P < 0.001) with dietary NPP concentration. Dietary Ca affected the intercept and linear component for ADG (P < 0.01), G:F (P < 0.05) and tibia ash concentration (P < 0.001), whereas for ADFI, it affected only the intercept (P < 0.01). Microbial phytase addition impacted on the intercept, the linear and the quadratic coefficient for ADFI (P < 0.01), ADG (P < 0.001) and G:F (P < 0.05), and on the intercept and the linear component (P < 0.001) for tibia ash concentration. An evaluation of these models was then performed on a database built from 28 experiments and 255 treatments that were not used to perform the models. Results showed that ADFI, ADG and Tibia ash concentration were predicted fairly well (slope and intercept did not deviate from 0 to 1, respectively), whereas this was not the case for G:F. The increase in dietary Ca concentration aggravated P deficiency for all criteria while phytase addition had a positive effect. The more P deficiency was marked, the more the bird response to ADFI, ADG, G:F and tibia ash concentration was exacerbated. It must also be considered that even if the decrease in dietary Ca may improve P utilisation, it could in turn become limiting for bone mineralisation. In conclusion, this meta-analysis provides ways to reduce dietary P in broiler diets without impairing performance, taking into account dietary Ca and microbial phytase.     

Preservation of crab or shrimp waste as silage for cattle

Five experiments were conducted to either ferment fresh shrimp or crab waste with molasses, molasses and bacterial inoculant, or to preserve it with salt. Experiment 1 was a 4 × 2 factorial arrangement. Crab waste was combined with 0, 5, 10, or 15% liquid molasses, and stored in mini-silos (15 l) with or without lids for 14 days. The addition of molasses slightly decreased pH and offensive odors; mini-silo temperatures without lids were higher than those with lids. Experiment 2 was a 5 × 2 factorial arrangement designed to enhance fermentation. Fresh shrimp waste was combined with 0, 10, 15, 20, or 25% dry molasses and 0 or 1.0 × 10⁸ colony forming bacteria/g inoculant and ensiled for six days. As the level of molasses increased, dry matter and lactic acid increased but, the pH, crude protein, ammonia acetic, butyric, and propionic acid concentrations decreased. Significant molasses by inoculant interactions occurred which were highly variable for each acid. Evidence of fermentation was supported by production of lactic acid at all levels of molasses. The pH decreased from 7.7 in the untreated waste to an average of 7.4 for the 10, 15 and 20% molasses treated wastes to 6.8 in the 25% molasses treated waste. The high pH was an indication that the waste may be unstable with longer storage (> 6 days). Therefore, in Experiment 3, designed as a 2 × 2 factorial arrangement, shrimp waste treated with 15 and 20% molasses, with or without inoculant was ensiled for 21 days to test stability. By day 21, shrimp waste had deteriorated as indicated by a mean pH of 7.5, low lactic acid, and high butyric acid concentration, an unacceptable odor, and the presence of mold on the surface of the samples.In Experiments 4 and 5, shrimp or crab waste was combined with salt at 0, 2.5, 5.0, 7.5, 10.0, and 12.5%. Increasing levels of salt decreased crude protein percent, ammonia concentration, and lactic and volatile fatty acids while increasing the pH and improving the acceptability of the odors in both the shrimp and crab wastes. Treatment of crustacean waste with 7.5% or greater salt was more effective at preserving crude protein and minimizing odor than either dry or liquid molasses.