Biocrust cover and successional stages influence soil bacterial composition and diversity in semiarid ecosystems

Biocrusts are an important drylands landscape component, which enriches the upper millimeters of the soil with organic matter and initiates biogeochemical cycles. However, little is known about the influence of biocrusts on soil bacterial community structure and diversity. Different biocrust types representing a successional gradient were studied. This gradient, from the earliest to the latest successional stages, consisted of an incipient cyanobacterial biocrust < mature cyanobacterial biocrusts < biocrust dominated by the Squamarina lentigera and Diploschistes diacapsis lichens < Biocrust characterized by the Lepraria isidiata lichen. Moreover, in each biocrust type, four different percentages of biocrust cover were also selected. Soil diversity gradually increased with biocrust successional stage and percentage of biocrust cover. The biocrust cover had an important role in the total abundance of bacteria, generally increasing in soils colonized by the highest percentages of cover. Biocrust successional stage was the most important factor, significantly influencing 108 soil bacteria genera, whereas biocrust cover showed significant differences in only 10 genera. Principal Component Analysis showed contrasting microbial composition across the biocrust successional gradient. Some bacterial taxa were dominant in the soil colonized by different biocrust types. Thus, Leptolyngbya, Rubrobacter, Solirubrobacter, Geodermatophilus, etc., were more abundant in incipient cyanobacteria; Nostocales, Chroococcidiopsaceae, Coleofasciculaceae etc., under mature cyanobacterial biocrusts; Truepera, Sphingobacteriaceae, Actinophytocola, Kribella, etc., below the S. lentigera and D. diacapsis community, and Bryobacter, Ohtaekwangia, Opitutus, Pedosphaeraceae, etc., in soils colonized by L. isidiata. Several soil bacteria taxa showed significant correlations (p < 0.05) with chemical soil properties (pH, total nitrogen, total organic carbon, available phosphorous and electrical conductivity). We discuss the role of biocrusts influencing these chemical soil parameters, including the presence of certain metabolites secreted by biocrusts, and also their effects on soil moisture and several physical soil features, as well as their association with different microclimates, all of which could favor a more selective environment for certain bacteria.

Raman spectroscopy detection of biomolecules in biocrusts from differing environmental conditions

Lichens and cyanobacteria colonize inhospitable places covering a wide climate range due to their different survival strategies, such as the synthesis of protective biomolecules. The effect of ecological factors on the synthesis of biomolecules has not been widely analysed. This study aimed to assess the effects of four factors (species, microclimate, seasonality and hydration state) and their interactions on the biomolecule frequency detected by Raman Spectroscopy. We included cyanobacterial biocrusts, and the lichens Diploschistes diacapsis, Squamarina lentigera, and Lepraria isidiata; two contrasted microclimates (typical and marginal), two contrasted seasons (hot and dry vs cool and wet) and two hydration states (dry and wet). "Species" was the most influential factor in the identity and frequency of the main biomolecules. Microclimatic differences in the range of the local specific habitats only influenced the biomolecules in cyanobacteria. There was a quadruple interaction among the factors, the effects being different mainly depending on the species. At D. diacapsis, the production of their main biomolecules depended on microclimate, although it also depended on seasonality. Nevertheless, in L. isidiata and S. lentigera microclimatic differences did not significantly affect the production of biomolecules. In the lichen species, the microhabitats exposed to relatively larger incident radiation did not show significantly larger relative frequency of photoprotective biomolecules. No clear connection between higher production of oxalates and drier microhabitats was found, suggesting that the synthesis of oxalates is not related to water reserve strategy. The pros and cons of monitor biomolecules in biocrust by Raman spectrometry were also discussed.

Ileal digestibility of amino acids of unheated and autoclaved pea protein concentrate in broilers

The effects of autoclaving 2 varieties of micronized (fine grinding) pea protein concentrate (PPC) on the ileal digestibility (ID) of CP and amino acids (AA) were studied in broilers. There was a control diet based on fermented soybean meal (FSBM) and 4 extra diets in which the FSBM was substituted on a CP basis by PPC from 2 different pea cultivars (PPC-1 and PPC-2), either unheated or autoclaved. Chicks were fed a common diet from 1 to 17 d of age and, then, their respective experimental diets from 18 to 21 d of age. Each treatment was replicated 6 times. Autoclaving reduced trypsin inhibitor activity (TIA) but had little effect on the saponin content of the PPC. The apparent ID (AID) of CP was similar for the FSBM and the unheated PPC and lower for both than for the autoclaved PPC. Autoclaving improved (P < 0.001) the AID of CP (87.6 vs. 82.2%) and most indispensable AA (e.g., 92.1 vs. 88.8% for Lys and 83.6 vs. 76.5% for Thr) of the PPC. The improvement in CP and AA digestibility with autoclaving varied with the PPC used and was consistent with the reduction in TIA observed (9.4 to 2.8 mg/g for PPC-1 vs. 9.1 to 5.3 mg/g for PPC-2). The standardized ID (SID) of most indispensable AA was similar for the FSBM and the PPC-2 and higher for both than for the PPC-1 (P < 0.05). For Lys, the lowest SID value was observed for the FSBM and the highest for the PPC-2 either unheated or autoclaved. It is concluded that the ID of the AA of the PPC improved with heating and was in general higher for the autoclaved PPC than for the FSBM. Consequently, heat processed PPC is a good alternative to FSBM and unheated PPC in starter diets for broilers.

Giant solitary synovial chondromatosis of the temporomandibular joint with intracranial extension

Synovial chondromatosis are rare entities but are well-described lesions in the literature that can affect many joint areas of the body. A case of tumoral synovial chondromatosis involving the temporomandibular joint with intracranial extension through mandibular fossa is reported. As long as there was significant infratemporal and extradural invasion of the middle and posterior fossa, a transtemporal and infratemporal approach was performed and total removal of the lesions was achieved. A brief review of skull base synovial chondromatosis is presented.

Influence of source of soybean meal and lysine content of the diet on performance and total tract apparent retention of nutrients in broilers from 1 to 36 days of age

The influence of soybean meal (SBM) source and total Lys content of the diet on performance and total tract apparent retention of nutrients was evaluated in broilers from 1 to 36 d of age. There were 6 treatments arranged factorially with 2 sources of SBM [regular SBM with 46.3% CP (R-SBM) and high-protein SBM with 48.6% CP (HP-SBM)] and 3 Lys:AME(n) ratios (Lys:ME; 380, 415, and 450 mg of total Lys:1,000 kcal of AME(n) from 1 to 21 d; and 312, 338, and 364 mg of total Lys:1,000 kcal of AME(n) from 22 to 36 d of age). From 1 to 36 d of age, broilers fed the HP-SBM diets had higher ADG and better feed:gain ratio (F:G) than broilers fed the R-SBM diets (P < or = 0.001). Both ADG and F:G improved (P < or = 0.05) with increases in the Lys:ME ratio. From 1 to 21 d of age, ADG and F:G (P < or = 0.001) were improved when the Lys:ME ratio increased and the benefits were more pronounced with the diets based on R-SBM. From 22 to 36 d of age, increasing the Lys:ME ratio from 312 to 338 increased ADG (P < or = 0.05) and F:G (P < or = 0.01), but no further improvements were observed when the ratio was increased to 364. The total tract apparent retention of DM and gross energy of the diets were higher (P < or = 0.05) for the HP-SBM than for the R-SBM diets. An increase in the Lys:ME ratio reduced organic matter and N retention (P < or = 0.05). The improvements in growth performance and nutrient retention observed in broilers fed the HP-SBM diets with respect to those fed the R-SBM are consistent with a better availability of nutrients of the high-protein meal. In addition, the results indicate that Lys requirements of broilers are at least, 30, 20, and 8% higher from 1 to 10, 10 to 21, and 21 to 36 d of age, respectively, than current NRC recommendations.

Influence of feed restriction and sex on growth performance and carcass and meat quality of Iberian pigs reared indoors

Iberian x Duroc pigs (n = 168), with an average age of 152 d and 42 +/- 2 kg, were used to investigate the effect of feeding regimen [ad libitum access to feed (AL) vs. 82% of AL from 152 to 201 d of age and 72% from 202 to 263 d of age (FR)] and sex (intact females, castrated females, and castrated males) on growth performance and carcass and meat quality. For the last 54 d before slaughter at 317 d of age, all pigs had AL access to feed. Between 152 and 263 d of age, pigs consuming AL had greater (P < 0.001) ADFI and ADG than FR pigs; however, when all pigs received AL access to feed (264 to 317 d of age), ADFI (P < 0.05), ADG (P < 0.001), and G:F (P < 0.01) increased in FR pigs compared with AL pigs. During the entire feeding period (152 to 317 d of age), ADG in FR pigs was less (P < 0.01) than in AL pigs. Feed-restricted pigs tended to have greater (P < 0.10) yields of trimmed hams and shoulders and less carcass fat than AL pigs, but feeding regimens did not affect chemical composition and color of meat. Intact females tended (P < 0.10) to have greater G:F and produced carcasses with less (P < 0.05) fat, greater (P < 0.01) proportions of primal cuts, and greater (P < 0.05) CP in the LM than castrated females and castrated males. It was concluded from this experiment that feed restriction applied from 152 to 263 d of age improved primal cut yields without affecting G:F, pork quality, and cured ham production traits. Moreover, intact females were superior to their castrated counterparts (particularly castrated females) in growth performance and primal cut yields. Therefore, feed restriction in intact females can be recommended as an acceptable practice for the production of Iberian pigs under intensive conditions.

Apparent ileal digestibility of energy, nitrogen, and amino acids of soybean meals of different origin in broilers

The coefficient of apparent ileal digestibility (CAID) of DM, gross energy (GE), N, and amino acids (AA) of 6 soybean meal (SBM) samples were compared in 21-d-old broilers. In addition, the digestibility of DM and N of diets that contained these SBM were tested in vitro. Four of the SBM were of South American origin, had a CP content varying from 45.2 to 47.2% and a trypsin inhibitor activity (TIA) varying from 4.1 to 6.5 mg/g, and were collected from local traders. The other 2 SBM were from US origin; one was a branded product with 48.6% CP and 1.8 mg of TIA/g and the other was obtained from soybeans of US origin that were dehulled and processed in Spain (50.6% CP and 2.4 mg of TIA/g). The experimental design was completely randomized with 6 diets and 6 replicates per treatment. Chicks were fed a commercial diet from 1 to 16 d of age and then their respective experimental diets for 5 d. The diets were based on sucrose and corn starch, with the SBM tested as the only source of protein. At 21 d of age, digesta was collected from the distal ileum and the CAID of nutrients was determined using celite as an indigestible marker. Diets that included the 2 SBM with the greatest CP content had greater CAID of DM (P Collapse

Key Words Collapse

MESH Headings

• Amino Acids/analysis
• Amino Acids/metabolism
• Animal Feed/analysis
• Animal Feed/standards
• Animal Nutritional Physiological Phenomena
• Animals
• Chickens/metabolism
• Diet/veterinary
• Dietary Fats/analysis
• Dietary Fats/metabolism
• Digestion/physiology
• Female
• Ileum/metabolism
• Male
• Nitrogen/analysis
• Nitrogen/metabolism
• Glycine max/chemistry

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Grants Collapse

Affiliation(s)

A de Coca-Sinova Urcacyl, 47007 Valladolid, Spain
D G Valencia
E Jiménez-Moreno
R Lázaro
G G Mateos

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The effects of feeding rice in substitution of corn and the degree of starch gelatinization of rice on the digestibility of dietary components and productive performance of young pigs1,2

A 28-d trial was conducted to evaluate the effect of the main cereal of the diet (corn or rice), heat processing (HP) of rice, and the degree of starch gelatinization (SG) of rice on apparent total tract digestibility (ATTD) of dietary components and productive performance of pigs weaned at 25 d of age. The experimental design was a completely randomized, with 4 treatments and 8 replicates per treatment (5 pigs penned together). Control pigs were fed a complex diet without growth promoters and based on milk products, fish meal, and 50% cooked and flaked corn, with a degree of SG of 84%. Experimental groups received the same complex diet as the control group, but the corn was substituted by rice with 3 different degrees of SG; 11% that corresponded to raw rice and 52 or 76% that corresponded to cooked rice processed under 2 different conditions. Pig growth was measured at 25, 39, and 53 d of age, and ATTD was determined at 29, 39, and 53 d of age. The ATTD of all dietary components except for N increased with age (P <0.01) and were greater for the rice than for the corn diet. Heat processing of rice improved ATTD of all dietary components at 29 d of age, but no beneficial effects were observed at 39 or 53 d of age. Modifying the conditions of HP to increase the degree of SG of rice from 52 to 76% and to reduce mean particle size from 480 to 405 mum did not result in further improvement of nutrient digestibility. From 25 to 53 d of age, pigs fed rice consumed more feed (678 vs. 618 g/d; P <0.05), grew faster (466 vs. 407 g/d; P <0.01), and tended to have greater G:F (0.685 vs. 0.662; P <0.10) than pigs fed corn. In fact, from 25 to 39 d of age, pigs fed rice consumed 23% more feed (P <0.01), grew 29% faster (P <0.01), and had 5% greater G:F (P <0.05) than pigs fed corn. Feeding rice improved performance of weanling pigs, and HP of rice under mild conditions enhanced diet digestibility and productive performance of pigs. Severe processing of rice increased the degree of SG but did not further improve diet digestibility or growth performance.

Effect of type of cereal, heat processing of the cereal, and inclusion of fiber in the diet on productive performance and digestive traits of broilers

We studied the influence of cereal, heat processing of the cereal, and inclusion of additional fiber in the diet on the productive performance and digestive traits of broilers from 1 to 21 d of age. Twelve treatments were arranged factorially, with 2 cereals (corn and rice), 2 heat-processing treatments of the cereals (raw and cooked), and 3 sources of fiber (none, 3% oat hulls, and 3% soy hulls). Each treatment was replicated 6 (trial 1) or 3 (trial 2) times. Growth traits were recorded in both trials; digestive traits were measured in trial 1, and total tract apparent retention (TTAR) of nutrients was determined in trial 2. Feeding rice improved TTAR of all nutrients and feed conversion from 1 to 21 d of age (P <or= 0.001). In addition, feeding rice increased the pH of gizzard digesta (P <or= 0.001) and reduced the relative weight (RW) of most digestive organs. Heat processing had little effect on the growth or size of digestive organs but improved the TTAR of most nutrients in the corn diets. Fiber inclusion improved the TTAR of most nutrients, BW gain (P <or= 0.01), and feed conversion (P <or= 0.001) from 1 to 21 d of age. In addition, fiber inclusion increased the RW of the gizzard (P <or= 0.001), ceca (P <or= 0.05), and digestive tract (P <or= 0.01) and reduced digesta pH (P <or= 0.001) and the length of the small intestine (P <or= 0.05). The effects of hulls on RW of the gizzard and on the TTAR were more pronounced for the rice diets than for the corn diets. We concluded that rice can be used successfully in broiler diets and that heat processing of the cereal does not have any beneficial effect on broiler performance. The inclusion of moderate amounts of fiber in low-fiber diets might improve chick performance at early ages by reducing gizzard pH and improving the utilization of nutrients. Therefore, young broiler chicks might require a minimal amount of fiber in the diet.

[Protocol proposal for the histological report of the primary tumor in patients with cutaneous melanoma from the Task Force for Cutaneous Melanoma of the Valencian Community]

This text compiles a histological protocol proposal for cutaneous melanoma agreed by the Task Force for Cutaneous Melanoma of the Valencian Community. It brings together the protocol itself and, in addition, includes a description of each of the proposed variables that has shown to have a greater prognostic impact in previous works.

Inclusion of oat hulls in diets for young pigs based on cooked maize or cooked rice

An experiment was conducted to investigate the influence of the main cereal (cooked maize or cooked rice) and the inclusion of cooked and expanded oat hulls (0, 20 or 40 g/kg) in the diet on total tract apparent nutrient digestibility (TTAD) and productive performance of piglets weaned at 21 days. Each of the six treatments was replicated eight times (five piglets penned together) and the trial lasted for 33 days. From 21 to 41 days of age piglets were given their respective experimental complex diets that contained 530 g/kg cooked cereal and from 41 to 54 days they received a common starter diet based on maize, barley and soya-bean meal. Growth promoters were not included in the diets. The TTAD was determined at 27 and 37 days of age and pig performance was measured at 31, 41 and 54 days of age. Nutrient digestibility increased with age (P<0·001) and in general were higher for rice- than for maize-based diets (P<0·001 for dry matter, organic matter and gross energy andP<0·05 for ether extract). From 21 to 41 days of age piglets given rice had higher food intake (FI,P<0·05) and average daily gain (ADG,P<0·01) than piglets given maize but food conversion ratio was not affected. The differences observed were maintained until the end of the trial. The inclusion of oat hulls in the diet did not affect TTAD of the nutrients but tended to reduce the incidence of diarrhoea from 21 to 41 days of age (P<0·1). Oat hulls inclusion reduced FI and ADG in diets based on maize but had the opposite effect in diets based on rice, indicating that piglets might have a minimum requirement for dietary fibre. It is concluded that cooked rice is an ingredient of choice in pre-starter diets for weanling pigs. Also, the inclusion of moderate levels of fibre as oat hulls reduces the incidence of diarrhoea and might improve productive performance in low fibre diets.

Determination of pesticides and PCBs in honey by solid-phase extraction cleanup followed by gas chromatography with electron-capture and nitrogen?phosphorus detection

A multiresidue method for determination of 15 organochlorine pesticides (OCPs), six polychlorinated biphenyls (PCBs), and seven organophosphorus pesticides (OPPs) is implemented for routine determinations of residues in honey. The method involves solid-phase extraction cleanup and determination by GC-ECD/NPD. Quantitation limits ranged from 0.1 to 0.6 microg kg-1 honey for OCPs and PCBs, and from 5.0 to 25.0 microg kg-1 honey for OPPs. Recoveries of OCPs ranged between 77.4 and 94.0%; for PCBs they were from 63.8 to 73.5%. Recovery assays for OPPs varied from 66.7 to 98.1%. The method was applied to the analysis of 111 honey samples from Aragon, Spain. The results obtained indicated a low level of contamination by pesticide residues and PCBs, which can contribute to ensuring the consumer has a safe wholesome supply of honey.

Feeding regimen and enzyme supplementation to rye-based diets for broilers

A trial was conducted to study the influence of feeding regimen [ad libitum, (AL) vs. feed restriction, (FR)] and supplementation of the diet with a combination of xylanase and beta-glucanase on physiological parameters and performance of broilers fed rye-based diets. There were 4 dietary treatments arranged factorially with 2 feeding regimens (0 vs. 30% FR from 4 to 14 d), 2 enzyme doses (0 vs. 500 ppm), and an additional corn control diet. Each treatment was replicated 9 times from 4 to 25 d (15 chicks caged together) and 6 times from 25 to 46 d. From 4 to 46 d of age, FR did not affect weight gain and improved feed conversion of broilers (P < 0.05). Also, FR reduced the incidence of leg disorders, digesta viscosity, and pasted vents (P < 0.01) and increased relative weight of gizzard (P < 0.001). Enzyme supplementation (ES) improved average daily gain and feed conversion at all ages (P < 0.01), and the beneficial effects were greater for AL than for FR birds (P < 0.10). Also, ES reduced digesta viscosity (P < 0.001), relative weights of gizzard (P < 0.05) and crop (P < 0.01), and jejunum length (P < 0.05). Compared with feeding corn, feeding rye AL with or without ES impaired growth and feed conversion from 4 to 46 d (P < 0.01) and increased incidence of leg disorders (P < 0.05), viscosity of jejunum content (P < 0.01), and jejunum length (P < 0.05). We concluded that rye in feed impaired broiler performance and increased digesta viscosity and incidence of leg disorders and that FR and ES reduced the magnitude of the problem. The beneficial effects of ES on bird performance were more evident when birds were fed AL.

The effects of gender and slaughter weight on the growth performance, carcass traits, and meat quality characteristics of heavy pigs1

Crossbred pigs (n = 192) from Piétrain x Large White sires mated to Landrace x Large White dams, with a mean BW of 75 +/- 1.3 kg, were used to investigate the effects of gender and slaughter weight (SW) on growth performance, carcass characteristics, and meat quality. Pens of pigs (eight pigs/pen) were assigned randomly to one of six treatments arranged in a 2 x 3 factorial design with two genders (barrows or gilts) and three SW (116, 124, or 133 kg). Each treatment was replicated four times. Over the entire trial, barrows had higher (P < 0.001) ADFI (as-fed basis) and ADG than gilts; however, gilts had higher (P < 0.05) gain-to-feed ratios (G:F) than barrows. Barrows had lower (P < 0.01) dressing percents than gilts and produced fatter (P < 0.001) carcasses that had lower trimmed shoulder (P < 0.10) and ham (P < 0.001) yields than gilts. There was a trend for the semimembranosus muscle (SM) from barrows to have a higher (P < 0.10) 45-min pH than that of gilts, but 24-h pH was 0.11 pH unit higher (P < 0.01) in the SM of barrows than gilts. Gender had no (P > 0.10) effect on the moisture and lipid content of the longissimus muscle (LM), nor did gender affect (P > 0.10) LM color, myoglobin content, or thaw loss percentage. However, the LM from barrows had lower (P < 0.05) cooking loss percentages and tended to have lower (P < 0.10) shear force values than the LM from gilts. Pigs slaughtered at 116 kg had higher (P < 0.05) ADG than pigs slaughtered at 124 and 133 kg. Daily feed intake (as-fed basis) was not (P > 0.10) different among SW; however, pigs slaughtered at 116 and 124 kg had higher (P < 0.001) G:F than those slaughtered at 133 kg. Dressing percent, backfat depth, carcass length, and ham and shoulder weights increased (P < 0.001) as SW increased from 116 to 133 kg. The initial (45-min) pH of the SM from pigs slaughtered at 133 kg was higher (P < 0.05) than from pigs slaughtered at 116 or 124 kg; however, 24-h pH was not (P > 0.10) affected by SW. The LM from pigs slaughtered at 133 kg was darker (lower L* values; P < 0.001), redder (higher a* value; P < 0.01), and had more (P < 0.001) myoglobin than the LM of pigs slaughtered at 116 and 124 kg. Barrows and gilts of this particular crossbreed can be used to produce acceptable quality fresh pork when slaughtered at 116 kg; however, increasing SW to 124 kg, or more, decreased live pig performance and carcass leanness without any additional benefits to pork quality attributes.

Heat processing of barley and enzyme supplementation of diets for broilers

The influence of heat processing (HP) of barley and enzyme supplementation (ES) of the diet on digestive and performance traits of broilers to 21 d was studied. There were four treatments arranged factorially with two barley-processing treatments (raw or heated), two levels of ES (0 or 500 ppm), and five replicates per treatment. Chicks fed HP barley grew faster than broilers fed raw barley until 8 d of age, but the effect disappeared thereafter. In general, ES improved broiler performance at all ages. Intestinal viscosity was increased by HP of barley (P < or = 0.05) and reduced by ES (P < or = 0.001), and the decrease in viscosity caused by ES was greater for HP than for raw barley diets (HP x ES; P < or = 0.05). Heat processing of barley and ES of the diet improved apparent retention of nutrients (P < or = 0.001). Age affected apparent retention of nutrients differently. For starch and neutral detergent fiber, retention increased linearly with age (P < or = 0.01), but for the remaining nutrients the retention decreased from d 4 to 8 and then increased until d 21 (P < or = 0.001). Also, the beneficial effects of HP on retention of nutrients were more pronounced at younger ages (HP x age; P < or = 0.05). Both HP (P < or = 0.001) and ES (P < or = 0.01) increased liver weight, and enzymes reduced the weights of pancreas (P < or = 0.05) and small intestine (P < or = 0.001). Villus height was improved by HP (P < or = 0.001) and ES (P < or = 0.01), but villus surface area was only improved by enzymes (P < or = 0.01). It was concluded that broiler performance is improved by HP of barley at early ages and by ES of the diet throughout the trial. Also, HP and ES increased apparent retention of nutrients, AMEn of the diet, and villus height.

Effect of enzyme addition to wheat-, barley- and rye-based diets on nutrient digestibility and performance of laying hens

1. Laying hen performance, egg quality, intestinal viscosity and nutrient apparent digestibility were evaluated with respect to the main cereal used in the diet and dosage rate of a fungal beta-glucanase/xylanase enzyme complex. 2. Twelve diets were arranged factorially, with three soluble fibre cereals (SFC); 500 g/kg of wheat or barley or 350 g/kg of rye, and 4 enzyme concentrations (0, 250, 1250 and 2500 mg/kg). An additional control diet based on maize was also included. 3. The use of SFC in the diet instead of maize did not affect egg production or food efficiency, but hens fed on SFC diets exhibited a higher incidence of dirty eggs than hens fed on the maize diet (8-6 vs 4.6%; P<0.01). 4. Laying hens fed on enzyme-supplemented diets produced more eggs (2.1%; P<0.05) and had better food efficiency per dozen eggs (2.5%; P<005) than hens fed on non-supplemented diets. An excess of enzymes in the diet (10 times the recommended dose) did not produce any deleterious effect on laying hen productivity. 5. Enzyme supplementation (ES) reduced intestinal viscosity (P<0.001) and the incidence of dirty eggs (P<0.01). The reduction in viscosity was more pronounced in barley than in wheat or rye diets (P<0.05). 6. Apparent nutrient digestibility in SFC diets was higher with ES, including dry matter (3.1%; P=0.08), fat (4.4%; P<0.001), non-starch polysaccharides (83.3%; P<0.01) and AMEn (2.5%, P<0.01). 7. It is concluded that substitution of maize by SFC is facilitated by ES, especially with respect to egg production, food conversion efficiency and egg shell cleanliness. An excess of enzymes did not produce any deleterious effect on nutrient digestibility or performance of laying hens.

Alpha-amylase supplementation of broiler diets based on corn

A 42-d trial was conducted to study the influence of exogenous alpha-amylase on digestive and performance traits in broilers fed a corn-soybean meal diet. There were two treatments (control and alpha-amylase supplemented diet) and six replicates (14 Cobb male chicks caged together) per treatment. At 7 d of age, alpha-amylase supplementation improved daily gain by 9.4% (P < or = 0.05) and feed conversion by 4.2% (P < or = 0.01). At the end of the trial, birds fed the alpha-amylase-supplemented diet ate more and grew faster (P < or = 0.05) and hadbetter feed conversion (P < or = 0.10) than broilers fed the control diet. Also, alpha-amylase supplementation improved apparent fecal digestibility of organic matter and starch (P < or = 0.01) and AMEn of the diet (P < or = 0.001). However, no effects were detected for CP or fat digestibility. Nutrient digestibility and AMEn of the diet increased with age (P < or = 0.001); however, no interactions of alpha-amylase x age were observed for any trait. Coefficients of apparent ileal and fecal digestibility of starch at 28 d of age were similar, which indicated that most of the undigested starch was not fermented in the hindgut of the chick. alpha-Amylase supplementation reduced relative pancreas weight (P < or = 0.001) but did not affect the weight of the remaining organs. Age consistently reduced intestinal viscosity and relative weights of all the organs (P < or = 0.001). The data indicated that alpha-amylase supplementation of a corn-soybean meal diet improved digestibility of nutrients and performance of broilers.

Influence of enzymes on performance and digestive parameters of broilers fed rye-based diets

An experiment was conducted to study the influence of enzyme supplementation (ES) to rye-based diets on rate of food passage through the digestive tract, viscosity of jejunum content, volatile fatty acid concentration in ceca, and performance of broilers. There were seven treatments; six diets arranged factorially with three varieties of rye (Petkus, Prima, and Saratov V) and two levels of ES (0 or 500 ppm of an enzyme complex containing 858 IU of beta-glucanase and 864 IU of xylanase/g) and an additional control diet based on corn. Each treatment was replicated seven times (12 chicks caged together), and the trial lasted 25 d. Rye feeding increased intestinal viscosity and impaired bird performance at 25 d (P < 0.001). Among rye diets the greatest feed intake and weight gain were obtained with Petkus variety, which also produced the lowest intestinal viscosity. Enzyme addition reduced the time needed to recover 1% (0.78 vs. 0.98 h; P < 0.05) and 50% (4.2 vs. 6.5 h; P < 0.01) of the marker in feces and reduced the mean retention time of marker in the gastrointestinal tract (17.1 vs. 18.8 h; P < 0.05). Also, ES reduced intestinal viscosity (P < 0.001) and improved feed intake, daily gain, and feed conversion of birds from 4 to 25 d (P < 0.01) but did not modify volatile fatty acid concentration in ceca. We concluded that ES added to rye diets decreased intestinal viscosity and accelerated digestive transit, improving productive performance of broilers.

[Prognosis value of p53 gene and cellular proliferation factors in malignant supratentorial gliomas]

OBJECT

The aim of this study was to investigate prognosis value of p53 oncosuppresor gene and labeling index by MIB-1 and PCNA monoclonal antibodies in malignant gliomas.

METHODS AND RESULTS

We operated 60 patient with malignant glioma between July 1994 and August 1998. Forty-five cases had the histopathological diagnosis of Glioblastoma Multiforme and fifteen cases of anaplastic astrocytoma or olygoastrocytoma. Initially we compare MIB-1/PCNA labeling index in eighteen cases. Patients < 40 years old, short period of symptoms preoperatively, only one cerebral lobe localization, total surgical exeresis, Karnofsky index > 70 postoperatively, low labeling index (MIB < 8.6%), forward radiotherapy treatment and surgical re-operation, were identified like favourable outcome factors in the uninvariable analysis. However to the multivariable analysis, only had outcome significance: patients < 40 years old, low labeling index, Karnofsky index > 70 postoperatively and surgical reoperation.

CONCLUSIONS

On the basis of the results of current analysis, moreover classical factors associated with better outcome, low labeling index to Glioblastoma Multiforme have been noted in patients with longer survival, and must be included to conventional histopathological studies.

Multiresidue determination of organochlorine pesticides and polychlorinated biphenyls in milk by gas chromatography with electron-capture detection after extraction by matrix solid-phase dispersion

A multiresidue analytical method based on matrix solid-phase dispersion was developed to analyze liquid milk for 22 organochlorine pesticides (OCPs) and 6 polychlorinated biphenyls (PCBs). Initial extraction is performed by loading 3 mL milk onto a 2.0 g octadecyl (C18)-bonded silica cartridge with n-hexane as the eluant. Neutral alumina column chromatography with sodium sulfate as the drying agent is used for further cleanup. The eluate is concentrated to 0.5 mL, and target analytes are determined by capillary gas chromatography with electron-capture detection. The optimized method was validated by determining accuracy (recovery percentages), precision (repeatability and reproducibility), and sensitivity (detection and quantitation limits) from analyses of milk samples fortified at 10 and 1 microg/L levels. Average recoveries were between 74 and 106% for all residues except beta-HCH, beta-endosulfan, and endosulfan sulfate. Both repeatability and reproducibility relative standard deviation values were < 22% for all residues. Detection limits ranged from 0.02 to 0.12 microg/L and quantitation limits were between 0.02 and 0.62 microg/L. The proposed analytical method may be used as a fast and simple procedure in routine determinations of OCPs and PCBs in milk.