Sunflower Meal Diets Research Articles

Effect of the diet on performance characteristics and quality of meat fat of lamb by principal component analysis

The objective of this study was to evaluate the effect of use of agroindustrial co-products in the diet of lambs on the performance and nutritional quality of meat fat. Twenty lambs were distributed into four experimental groups: control diet (C) or diets containing cottonseed (CS), sunflower meal (SFM), and castor cake (CC). During the experimental period, data on dry matter consumption (DMC) and total weight gain (TWG) were collected. After slaughter, samples of Logissimus dorsi (LD) muscle were taken for fatty acids and cholesterol analysis. Diets C and CS provided similar characteristics of fat quality and animal performance. However, SFM and CC diets tend to form isolated groups, with different fat and performance characteristics. The SFM diet results in meat with a higher saturated fatty acids and cholesterol content. The CC diet is related to improved performance characteristics and lower cholesterol content. In conclusion, the inclusion of CC in the experimental diets provided, in the proportions used in this experiment, better characteristics of animal performance and meat fat quality.

Phytase supplementation effects on amino acid digestibility depend on the protein source in the diet but are not related to InsP6 degradation in broiler chickens

The objective was to determine phytase effects on prececal amino acid (AA) digestibility and phytate (InsP6) breakdown when different oilseed meals were used in broiler chicken diets. The study included 14 diets: a corn-soybean meal (SBM) basal diet and 6 diets that contained SBM, rapeseed meal (RSM), and sunflower meal (SFM) with 2 inclusion levels at the expense of corn starch (150 and 300 g/kg SBM or SFM, or 100 and 200 g/kg RSM). Each diet was mixed with or without a phytase supplement of 1,500 FTU/kg. Diets were provided to broilers for 5 D. Digesta from the posterior half of the ileum were collected on day 21. The average essential AA digestibility, calculated by a regression approach, without and with phytase was 84 and 85% (SBM), 74 and 77% (SFM), and 66 and 73% (RSM), respectively. In the diets, phytase effects on AA digestibility were lower owing to other protein sources also present in the diet, but significant. Prececal InsP6 disappearance was significantly affected by interactions between oilseed meal, inclusion level, and phytase supplementation. Overall, prececal InsP6 disappearance was higher in SBM diets (52%) than in SFM diets (38%) and intermediate in RSM diets (43%). Across diets, phytase supplementation effects on prececal InsP6 degradation linearly increased with the InsP6 concentration of the diet up to 12 g/kg DM. The only exception from linearity was the diet with the high inclusion of SFM, which contained 15.9 g InsP6/kg DM. In the ileal content, the concentration of myo-inositol was significantly increased by phytase supplementation, and this effect was highest in the diets that contained SBM as the only oilseed meal. Concentrations of lower inositol phosphates were increased by phytase supplementation, and this effect was most remarkable for Ins(1,2,3,4)P4 and inositol tetrakisphosphates. The study showed that phytase effects on AA digestibility varied among the 3 tested oilseed meals, but these differences were not detectable in the diets containing these meals. Although phytase effects on ileal content of InsP6 and its degradation products were substantial, they were not related to the effects on AA digestibility.

Effect of non‐starch polysaccharide composition and enzyme supplementation on growth performance and nutrient digestibility in Nile tilapia ( Oreochromis niloticus )

The experiment investigated whether the effect of enzyme supplementation on performance and nutrient digestibility is dependent on type of the ingredient(s) used, by incorporating wheat bran (WB), sunflower meal (SFM) and citrus pulp (CP) to a reference diet (REF). Those ingredients are known to be rich in different types of non‐starch polysaccharides (NSP). Diets were supplemented with and without (control) an enzyme mix (phytase 1,000 FTU/kg and xylanase U/kg) according to a 2 × 4 factorial arrangement. In total, 24 tanks (3 replicates/treatment) were used with 30 fish each (Nile tilapia, Oreochromis niloticus; mean initial body weight 41 g). Fish were restrictively fed the experimental diets for 43 days (80% of expected satiation). Enzyme supplementation affected the absolute growth (g/day) and FCR (p < 0.05), improving the growth of fish fed the WB and SFM diets, while fish fed the REF and CP diets did not benefit. NSP, energy, ash, phosphorous and calcium digestibility improved with enzyme supplementation (p < 0.05). There was an interaction effect on all growth parameters, as well as the digestibility of energy and phosphorus (p < 0.05). This indicates that the effectiveness of the enzymes was dependent on the NSP‐rich ingredient used and thus the composition of the NSP fraction

Fatty acid composition in muscles from lambs fed diets containing agroindustrial co-products

The objective of this study was to evaluate the effects of supplementing diet of lambs with agroindustrial co-products on the nutritional quality of meat fat and study the variation of fat quality parameters based on the type of muscle. Twenty lambs were distributed into four experimental groups and fed a control diet or diets containing cottonseed, sunflower meal, and castor cake. After 106 experimental days, the animals were slaughtered. Samples of Biceps femoris, Longissimus dorsi, Semimembranosus, and Triceps brachii muscles were taken for fatty acid and cholesterol analyses. Castor cake and sunflower meal diets produced meats with lower levels of n-6 polyunsaturated fatty acids (PUFA) compared with the control diet. Castor cake diet contributed to tissue reduction of n-3 PUFA. Lower conjugated linoleic acid concentration and polyunsaturated:saturated fatty acid (P:S) ratio and higher saturated fatty acids content and Thrombogenicity Index were observed in Longissimus dorsi meat. Of the co-products studied, although castor cake diet reduced cholesterol levels in Biceps femoris muscle, sunflower meal was identified as the preferred choice for lamb feeding, since it reduced n-6 PUFA without, however, decreasing n-3 PUFA. Longissimus dorsi meat had the lowest fat quality indexes. The more oxidative muscles, such as Biceps femoris, tend to generate meats with higher cholesterol concentrations.

Comparing two techniques for viscosity measurements in poultry feedstuffs: does it render similar conclusions?

Viscosity of intestinal contents is known to affect digestion and absorption of nutrients. In most poultry studies, intestinal viscosity has been measured only after complete removal of solid particles by centrifugation. Centrifugation may however remove particles that contribute to viscosity, hence giving rise to an underestimation of viscosity. Two viscosity measurement techniques, one including a centrifugation step (Brookfield) and the other without (Haake), were compared in-vitro to assess whether both techniques result in similar conclusions regarding viscosity in feedstuffs. Two sets of feedstuff preparations were used. The first set was prepared with different combinations of milled feedstuffs in order to have a wide range of viscosity: 100% corn, 25% corn + 75% wheat, 100% wheat, 90% wheat + 10% rye, all mixed with distilled water. In the second set, barley was incubated with different beta-glucanases, and soybean and sunflower meal were incubated with different pectinases, again all mixed with distilled water. Viscosity was assessed using both techniques (Haake and Brookfield equipments) at six different time points. To evaluate the extent of agreement between the two methods, the Lin's concordance correlation coefficient (CCC) was assessed using the percentage of increase in viscosity within each method, based on pairwise feedstuffs comparison (first set), or relative to the feedstuff without enzyme (second set). The rate of the agreement between the two methods was substantial for the first set of feedstuffs (66%) and for the barley diets incubated with beta-glucanases (69%), whereas the CCC score for the soybean meal diets was very poor (2%) and fair for the sunflower meal diets, incubated with pectinases (32%). The lack of agreement for the latter can be explained by the limited variation in viscosity in these low-viscous mixtures. Although the two techniques are considerably different (e.g., with or without preceding particle removal), they seem to render similar conclusions when applied to poultry feedstuffs to identify distinct differences under the tested circumstances.

Effects of replacing soybean meal with alternative sources of protein on nutrient digestibility and energy value of sheep diets

The study determined the potential of eight locally produced protein sources to replace soybean meal (SBM) in the diet of sheep. Three in vivo digestibility trials were conducted using a Latin square (3x3, 4x4 and 4x4) experimental design with castrated Chios rams. The authors estimated nutrient digestibility coefficients and energy value of diets with soybean meal (control), lupin seeds (LS), rapeseed meal (RSM), sunflower meal (SFM), fababean seeds (FBS), vetch seeds (VS), pea seeds (PS), flaxseeds (FS), and chickpea seeds (CS). The results showed that the SBM, RSM, and PS diets had similar nutrient digestibility and energy value. The SFM diet had lower organic matter (OM) digestibility than the SBM diet. The FS and SFM diets had similar crude protein (CP) digestibility to the SBM diet. Additionally, FS, VS, and SBM diets had similar energy value. Furthermore, SBM, SFM, VS and FS diets had similar dry matter (DM), neutral detergent fibre (NDF), hemicelluloses, and cellulose digestibility coefficients. The SBM, LS, FBS, and CS diets had similar DM, OM, NDF, hemicelluloses, and cellulose digestibility coefficients. Additionally, SBM, LS, and CS diets had similar energy value. This study reveals that diets with RSM, PS, FS, and LS, compared with diets with SBM, did not have adverse effects on nutrient digestibility and energy value. These results tend to support the idea that some locally available protein sources seem to have the potential to replace SBM in sheep diets.Keywords: Dietary supplementation, nutrition, nutrient digestibility, protein, ruminants

Evaluation of rye specimens in maturity stage on the basis of mathematical – statistical analysis

Two experiments were conducted to investigate effects of rapeseed meal (RSM) vs. sunflower meal (SFM) as a protein source at cereal-based iso- nitrigenous (at 16 % CP), iso-caloric at gross energy 18 kcal/kg and net (FUG=1) energy diets for fattening lambs. Four wethers (Gygay breed) were used to evaluate the diets' apparent total tract digestibility (dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), crude fibres (CF), nitrogen free extractives (NFE) and ash) and coefficients (Cd) were used to calculate the diets' feeding value. Two diets were used: conrol diet (CD) with SFM and experimental diet (ED) with RSM. The results indicated that feeding RSM tended to increase Cd OM (p=0.1), Cd CP (p=0.4), Cd EE (p=0.5) and Cd NFE (p=0.1). The differences were significant at Cd DM (p<0.05), Cd CF (p<0.05) and Cd ash (p<0.001). According to the calculation analysis, diet supplementation with RSM benefits total digestible nutrients (TDN), raised energy values (gross energy, digestible energy and net energy) and improved protein feeding values (protein trully digestible in small intestines (PDI) and balance of protein in rumen (BPR)). Therefore, it's concluded that, substitution of SFM with RSM in cereal- based ruminant diets significantly (p<0.05) increased in vivo diet digestibility, raised (11 %) TDN and improved its energy and protein feeding value.

Performance of broilers fed with different levels of sunflowermeal supplemented with or without enzymes

In this study, it was aimed to determine the performances and some carcass and small intestine properties of broiler chickens fed diets in which sunflower meal (SFM) replaced soybean meal (SBM) and supplemented or not with multi-enzyme. With this aim, a total of 450 1-day-old age mixed-sex Ross 308 broiler chicks were used in a completely randomized design, with five treatments and three replicates of thirty birds each. The experimental diets consisted of a control group and two levels of SFM with or without enzyme replacing 50 or 100% of SBM protein, respectively. Hence, treatment groups were: control (100SBM), 50SFM, 100SFM, 50SFME, and 100SFME). Feed and fresh water was given freely. At the end of the experiment (42 days of age), 100SBM broilers had higher body weight and cold carcass weight than all other groups (P is less than 0.05) and had lower feed conversion ratio (FCR) compared to 50SFME broilers (P less than 0.05). Feed consumption, weights of hearth, liver, gizzard, abdominal fat and small intestine and length of small intestine were not found different among the groups (P is less than0.05). Our observations demostrated that addition of the 0.05% multi-enzyme mixture into SFM diets of broiler chickens had not positive impact on the availability of SFM and broiler performance

Effect of Partial Substitution of Fish Meal with Sunflower Meal on Feed Utilization, Intestinal Digestive Enzyme, Hematological Indexes, Intestinal, and Liver Morphology on Juvenile Turbot (Scophthal musmaximus L.)

A 70-day feeding trial was conducted to evaluate effects of partial substitution of fish meal (FM) by sunflower meal (SFM) on juvenile turbot (Scophthal musmaximus L.). Five isonitrogenous and isoenergetic diets were formulated with 0%, 15%, 25%, 35%, and 45% replacement of FM protein with protein from SFM. Triplicate groups of juvenile turbot (30 fish per group), were hand-fed twice daily to apparent satiation. Final body weight (FBW), specific growth rate (SGR), and weight gain rate (WGR), were not significantly influenced by type of plant protein at the 15% level (P&gt;0.05), while higher levels showed significant reduction of FBW, SGR, WGR. Feed efficiency ratio (FER) and feed intake (FI) were significantly influenced when FM protein was replaced up to 45% (P&lt;0.05). Body composition parameters were not affected by SFM substitution but body crude lipid was lowest and ash was highest at 45% (P&lt;0.05). Trypsin and diastase values did not vary with experimental diets but lipase activity was significantly reduced (P&lt;0.05). Catalase (CAT) values were significantly lower than the control (P&lt;0.05) when substitution level reached or exceeded 35%; no significant differences were observed in total antioxidant capacity (T-AOC) and malondialdehyde (MDA) values (P&gt;0.05). In the SFM diet groups, all superoxide dismutase (SOD) values were significantly higher than the control (P&lt;0.05); villi length and enterocytes were significantly reduced (P&lt;0.05), but there was no significant difference (P&gt;0.05) in microvilli height between diets; parenchyma structure of liver was severely damaged; smaller hepatocyte areas and areas with high levels of hepatocyte vacuolization and disorganization were present. All results indicated that SFM protein can partially replace FM protein in juvenile turbot diets without adverse effects.

Influence of Substituting Dietary Soybean for Air‐Classified Sunflower (Helianthus annuus L.) Meal on Egg Production and Steroid Hormones in Early‐Phase Laying Hens

Soybean meal (SBM) is the most widely and expensive protein source used in the formulation of poultry diets; however, when the price of SBM increases, poultry nutritionists seek alternative sources that are more economical in formulating least-cost rations. This research aimed to evaluate the effects of dietary air-classified sunflower meal (SFM) on some productive parameters and plasma steroid hormones in laying hens. In this trial, 20-week-old laying hens (ISA Brown strain) in the early phase of production were randomly assigned to two groups and fed wheat middlings-based diets containing soybean (135g/kg; 48% CP) or air-classified SFM (160g/kg; 41% CP) as the main protein source. Laying performance, egg size and feed conversion ratio were evaluated for 10week. Plasma steroid hormones (progesterone and oestradiol) in the hens were quantified weekly. Substituting SBM with air-classified SFM did not change (p>0.05) the hens' growth performance, whereas feed consumption and efficiency were positively influenced (p<0.05) by SFM treatment. Egg production rate was improved in hens fed the SFM diet (p<0.05), as well as the percentage of medium-size eggs that was higher for SFM treatment (p<0.05). Steroid hormones levels were affected by dietary treatment (p<0.01). From our findings, it could be effective to include air-classified SFM in early-phase laying hen diets as an alternative protein source substituting SBM, without negative influence on productive performance and egg traits, reducing also the production costs.

The effects of less-expensive plant protein sources replaced with soybean meal in the juvenile diet of grass carp (Ctenopharyngodon idella): growth, nutrient utilization and body composition

In this study, the effects of less-expensive protein sources replaced with soybean meal on growth performance, nutrient utilization and body composition of juvenile grass carp were investigated. For this purpose, a control diet containing 42% soybean meal was prepared. Cotton seed meal (CSM), sunflower meal (SFM) and corn meal (CM) were added to the experimental diets by replacing 100% of the soybean meal protein used in the control diet. All diets were iso-nitrogenous (40% crude protein) and iso-caloric (19.5 MJ kg−1 gross energy). Each treatment had three replicates, and 20 juvenile grass carps (3.5 ± 0.1 g, initial weight) were located in per replicate. The fish were fed to satiety three times in a day during 3 months at 26°C of water temperature in glass aquarium (45 l). The results of the study showed that the weight gain (308.6–448.6%), specific growth rate (1.56–1.89%/day), feed conversion rate (1.2–1.9), protein efficiency ratio (1.32–2.08), and apparent digestibility coefficients of protein (80.5–89%) or sum of amino acids (80.5–88.9%) were not significantly affected by the experimental diets, except diet CM. All of these values obtained for the diet CM were significantly lower than those of fish fed on the control, CSM and SFM diets. However, there were no significant differences between the lipid digestibility of the diets, and crude protein, lipid, and gross energy contents in the whole body of fish in experiments. In conclusion, CSM and SFM diets were highly utilized by juvenile grass carp, but not CM diet. These results combined with the remarkable acceptability of diets containing high levels of plant protein ingredients with identical growth performances of juvenile grass carp show clearly that dietary soybean meal level can be considerably reduced without any adverse consequence in terms of somatic growth and nitrogen utilization.

Consumo e digestibilidade de dietas contendo fontes energéticas associadas ao farelo de girassol ou ureia em novilhos confinados

The aim of this study was to evaluate the intake and total and partial digestibility of diets using corn, soybean hulls and citrus pulp associated with sunflower meal or urea in feedlot steers. Four steers ½ Aberdeen Angus vs. ½ Nellore, fitted with rumen and duodenum cannulas, with 18 months old and 360 kg of initial weight. The diets were composed of two energy sources (corn and citrus pulp) associated with two nitrogen sources (urea and sunflower meal), in a total of four treatments, with forage:concentrate ratio of 40:60. The statistical design was a Latin square with four treatments and four periods of 21 days each. The average daily dry matter intake was influenced (p < 0.05) by the diets, with the highest value was observed in corn and sunflower meal diet. The apparent digestibility of all components, except the crude protein, was higher (p < 0.05) for diets with citrus pulp. There was no effect (p > 0.05) among diets for ruminal and intestinal digestibility. The use of co-products in animal feed did not impair the digestibility of diets and are shown as high potential ingredients for use in beef cattle diets.

Whole white lupin ( Lupinus albus cv. Amiga) seeds as a source of protein for growing-fattening rabbits

The purpose of this study was to evaluate the effect of substituting 100 g soybean meal (SBM) for 150 g whole white lupin seeds (WL, Lupinus albus cv. Amiga) or 170 g sunflower meal (SFM)/kg diet as protein source for growing-fattening rabbits. The SFM diet contained more cellulose and lignin, and less digestible energy than the other diets whereas the WL diet contained more oligosaccharides of the raffinose series. In the performance trial, 90 weaned Hyplus rabbits (30 per treatment) were individually housed and fed one of the three experimental diets for 42 days (37–79 days of age). At the end of the trial period, 18 rabbits per treatment were slaughtered and used for the evaluation of carcass traits. In addition, the coefficient of total tract apparent digestibility (CTTAD) of the diets and caecal traits were determined from 48 to 52 days of age in 13 rabbits per treatment. Diet did not affect weight gain or feed conversion ratio but feed intake was higher with the SFM diet ( P<0.05). Dressing-out percentage was higher in rabbits fed the WL diet than in rabbits fed the other diets ( P=0.006). Diet did not affect CTTAD of organic matter, crude protein or ether extract. Rabbits fed the SFM diet had lower neutral detergent fibre digestibility ( P<0.05) and tended to have lower gross energy and acid detergent fibre digestibility than rabbits fed the other diets. In addition, pH, volatile fatty acid and ammonia concentration in the caecum were not affected by diet; however, lactic acid concentration was increased with WL feeding ( P<0.05). It is concluded that whole white lupin seeds can replace satisfactorily soybean meal and sunflower meal in diets for growing-fattening rabbits.

Effect of Enzyme Addition on the Nutritive Value of High Oleic Acid Sunflower Seeds in Chicken Diets

Two experiments were conducted to evaluate the effects of enzyme addition in chicken diets containing high oleic acid sunflower seeds (HOASS). In the first experiment (4 to 21 d of age), enzyme addition (lipase, phospholipase, and a combination of these) was used at the inclusion level of 1 g/kg in diets containing HOASS (250 g/kg) compared with a control corn-soybean diet. Weight gain, feed consumption, relative liver weight, fat digestibility, and amylase, lipase, serum lactate dehydrogenase (LDH), and creatine phosphokinase (CPK) activities were reduced, and feed conversion, relative duodenum, jejunum, ileum, and ceca lengths, plasma uric acid, cholesterol, and glucose concentrations were increased in the unsupplemented HOASS diet compared with the control diet. The addition of enzymes to the HOASS diet increased weight gain, feed consumption, relative pancreas and liver weights, fat digestibility, amylase and lipase activities, plasma uric acid, calcium, serum LDH and CPK, and total protein concentration and reduced feed conversion, relative spleen weight, relative duodenum, jejunum, ileum, and ceca lengths, plasma cholesterol, and glucose compared with the unsupplemented HOASS diet. In the second experiment (0 to 21 d of age), the same enzymes (0.5 g/kg each) were included in diets containing 150 g/kg of HOASS compared with a conventional sunflower meal diet (150 g/kg). The HOASS diet did not affect performance but reduced relative pancreas and abdominal fat weights and relative duodenum and ceca lengths, and increased crude fat, CP, and essential and nonessential amino acid digestibilities (except Ser, which was reduced) compared with the control diet. The addition of enzymes in the HOASS diet increased weight gain, feed consumption, and relative pancreas weight and reduced feed conversion, CP, and essential and nonessential amino acid digestibilities compared with the unsupplemented HOASS diet. In conclusion, the addition of 250 g of HOASS/kg in the diets caused a negative effect on performance, digestive organ sizes, fat and protein digestibilities, and pancreatic enzymes and modified blood parameters. However, the inclusion of HOASS at 150 g/kg improved some of these parameters and amino acid digestibilities. The enzyme addition counteracted some of these effects.

Re-evaluation of crude fibre and acid-insoluble ash as inert markers, alternative to chromic oxide, in digestibility studies with rainbow trout ( Oncorhynchus mykiss)

The validity of crude fibre and acid-insoluble ash as inert markers as alternatives for chromic oxide was tested for digestibility studies in rainbow trout. Six practical diets were assayed: one of fish meal (C), and five in which 40% of the fish meal protein was replaced by corn gluten meal (CGM), cottonseed meal (CSM), lupine seed meal (LSM), soybean meal (SBM) or sunflower meal (SFM) on a crude protein basis. The apparent digestibility coefficients for crude protein, NFE, dry matter and gross energy were calculated using crude fibre, acid-insoluble ash and Cr 2O 3 as inert markers. For all diets, when acid-insoluble ash was used as the marker, results for the apparent digestibility coefficients for crude protein, NFE, dry matter and gross energy were higher ( P<0.05) than those based on Cr 2O 3. All apparent digestibility coefficients for the control, corn gluten meal, cottonseed meal and lupine seed meal diets calculated with crude fibre as the marker were similar to those based on Cr 2O 3, whereas all results based on crude fibre for the soybean meal and sunflower meal diets, compared with those obtained with chromic oxide, were lower ( P<0.05). Based on these results, if one considers chromic oxide as the reference marker, then acid-insoluble ash is not a suitable marker for digestibility studies in rainbow trout. With respect to crude fibre, our results suggests that this substance can be an effective endogenous marker, although attention should be paid to the type of crude fibre present in the diets.

Liver and white muscle protein turnover rates in the European eel ( Anguilla anguilla): effects of dietary protein quality

The influence of the quality of dietary protein source on growth and protein synthesis and degradation rates was studied in the liver and white muscle of the European eel. Fish were fed isonitrogenous diets differing in protein source: one (control) contained fish meal, three others incorporating meat meal (MM) or sunflower meal (SFM) as the only protein source, and SFM supplemented with some essential amino acids (EAAs) were also tested. Fish fed diets containing unsupplemented MM or SFM exhibited dietary utilization and growth indices poorer than those fed the control, while EAA supplementation greatly improved the performance of the SFM-diet. Liver showed higher rates of protein synthesis ( k s) and degradation ( k d) associated with a higher capacity for protein synthesis per unit of DNA but a lower protein deposition efficiency (PDE), compared to muscle. Low quality dietary protein increased the protein turnover rate, with a higher protein synthesis rate per unit of DNA and RNA but a decrease of PDE. In white muscle, MM and unsupplemented SFM diets decreased k s without changing k d. The MM diet reduced the efficiency of protein synthesis and deposition. EAA supplementation of the SFM diet raised the protein synthesis rate and capacity as well as protein deposition compared to control values.

Rumen microbial production estimated either from urinary purine derivative excretion or from direct measurements of 15N and purine bases as microbial markers: effect of protein source and rumen bacteria isolates

AbstractFour ewes fitted with ruminal and duodenal T-piece cannulae were each given six diets in a 6 × 4 factorial design. Diets or experimental treatments consisted of two ratios of forage: concentrate (700:150 (LC) and 400: 600 (HO). Forage was ammonia-treated straw and the concentrate was formulated with barley supplemented with one of three protein sources: sunflower meal, soya-bean meal or fish meal. Duodenal flows ofdigesta were estimated by the dual-phase technique using Co-EDTA and Yb acetate as liquid and solid markers. Microbial nitrogen (N) was estimated from the digesta flow of purine bases and 15N enrichment using as reference samples, bacterial isolates from the liquid (LAB) or solid (SAB) phase of rumen digesta.Duodenal flow of purine bases (mmol/day) was lower on LC (12·9) than HC (17·7) diets but in both treatments it was depressed by fish meal (12·3) compared with either soya-bean (17·3) or sunflower meal (16·3) as supplements (s.e. 1·13). Urinary excretion of purine derivatives showed a similar trend, 8·6 v. III mmol/day in LC and HC respectively and 8·8 v. 10·4 and 10·5 mmol/day in fish meal, soya-bean and sunflower meal diets (s.e. 0·56), respectively. Variation in excretion of urinary purine derivatives was mainly associated with digestible organic matter intake with an average ratio of 1·7 (s.e. 0·11) mmol per 100 g digestible organic matter intake. Irrespective of the microbial marker used, microbial yield was higher in animals offered HC than in those offered LC and with soya-bean or sunflower meal compared with fish meal supplemented diets. The microbial purine bases/N (mmol/g) ratio varied between LAB (1·99, s.e. 0·092) and SAB (1·69, s.e. 0·071) isolates leading to different estimates of microbial-N yield (g) from duodenal purine bases (7·76 (s.e. 2·84) v. 9·13 (s.e. 3·24)), urinary excretion of allantoin (5·57 (s.e. 2·0) v. 6·57 (s.e. 2·03)) or total purine derivatives (6·43 (s.e. 2·39) v. 7·56 (s.e. 2·77)). Urinary excretion of allantoin or total purine derivatives provided consistently lower estimates of duodenal microbial-N than duodenal purine bases or 15N, although it closely reflected the pattern observed in direct measurements.

Enzyme Supplementation of a Barley and Sunflower-Based Diet on Laying Hen Performance

A laying hen trial was performed to determine the effect of increasing levels of an enzyme preparation (Grindazym GP 5000) on productive parameters, egg quality, water consumption, and excreta quality of a barley and sunflower meal containing diet for laying hens. Six hundred and forth white Shaver 2000 caged laying hens received a 60% barley-20 sunflower meal diet with either 0, 0.5, 0.75, or 1.0 g enzyme/kg feed from 26 to 41 wk (four months in total). The commercial enzyme preparation contained 5,000 units/kg of β-glucanase, 12,000 units/g of xylanase, and 10 units/g of pectinase. During the first four weeks, the highest dose of enzyme (1 g/kg feed) increased egg weight by more than 1 g, improved the percentage of eggs heavier than 60 g, and enzyme supplementation reduced the percentage of dirty eggs. Enzyme addition reduced water intake and the feed:water ratio. High doses of enzyme improved excreta quality. There were no significant differences in rate of lay, daily feed intake, and body weight gain due to enzyme addition.

Effect of Protein Source on Ruminal Fermentation and Passage of Amino Acids to the Small Intestine of Lactating Cows

Four lactating Holstein cows, fitted with T-type cannulas in the proximal duodenum, were used in a 4 × 4 Latin square design to determine the effect of protein supplement on production, ruminal digestion, and profile and the quantity of AA available for absorption. Supplemental protein sources were blood meal, corn gluten meal, blood meal plus corn gluten meal, and sunflower meal, which constituted 8, 10.5, 9.3, and 13% of dietary DM, respectively. The DMI and milk production were not influenced by treatment. Ruminal NH3 concentration increased with the sunflower meal diet, and molar percentage of propionate decreased with the blood meal diet. Duodenal flow of NAN was unaffected by protein source, but dietary N flow decreased, and bacterial N flow increased, when cows were fed the sunflower meal diet. Bacterial N flows were 46.0, 45.3, 46.4, and 65.8% of NAN for the respective diets. The AA profiles of isolated ruminal bacteria differed among dietary treatments but were not correlated with the respective supplementary protein sources. The essential AA profiles of duodenal digesta and duodenal flow of individual AA closely reflected AA differences in protein sources, suggesting that the composition of RUP profoundly affected the composition of protein entering the intestine when supplemental protein provided 35% of total CP intake.

Rape and sunflower seed meals as supplements for sheep fed on oat straw

Rapeseed meal (RSM), sunflower meal (SFM) and formaldehyde-treated (F) forms of these were compared with urea- and formaldehyde-treated casein (FCAS) as N supplements for sheep fed pelleted diets containing c. 80% oat straw. Sufficient supplement was added to bring the N content of each diet to c. 1.7%, and starch was added to the urea and FCAS diets to make all supplements equal in metabolizable energy content. Based on an assumed fractional outflow rate from the rumen of 0.06 h-1, the ruminal degradability of dietary N varied from a mean of 0.42 for diets containing formaldehydetreated supplements to 0.74 for non-treated supplements. The diets were fed to Crossbred wethers weighing c. 40 kg in a production experiment lasting 12 weeks, and in a metabolism experiment. In the production experiment, penned sheep fed the urea diet ate 1300 g DM day-1, gained 30 g Day-1 and grew 4.5 g clean dry wool (CDW) day-1 . Each of the protein supplements increased DM intake (mean 1860g day-1 P &lt; 0-0l), liveweight gain (mean 148 g day -I, P &lt; 0-001) and wool growth (mean 10.5 g CDW day-1; P &lt; 0.01). Intake and liveweight gain were higher, and wool growth rate lower, on the SFM than on the RSM diet, while formaldehyde treatment of both meals stimulated intake, gain and wool growth although these differences were not always significant. Efficiency of wool growth, expressed as g CDW per g N digested, was least for the urea and SFM diets (mean 0.30), higher for the FCAS, RSM and FSFM diets (mean 0.40) and highest for the FRSM diet (0.48, P &lt; 0.05). Mean digestibilities of organic matter (OM) and cell wall constituents for all diets were 0.47 and 0.44 respectively, with few significant differences between diets. Apparent N digestibility varied from 0.41 to 0.61 for the FRSM and FCAS diets respectively, while estimated true N digestibility varied from 0.72 to 0.88 for the same two diets. Nitrogen balance for the protein-supplemented diets (mean 2.68 g day-1) was higher (P &lt; 0.001) than for the urea diet (-3.77 g day-1). During 6 h post-feeding, the mean rumen pH (6.50) and volatile fatty acid levels (60.9 mM ) showed few differences between diets, whereas rumen ammonia concentrations were significantly reduced by formaldehyde treatment of the protein supplements. It was concluded that RSM and SFM were effective supplements for sheep offered straw, with little difference between them except for wool growth. Formaldehyde treatment to confer resistance to ruminal degradation reduced N digestibility, but increased the efficiency of utilization of digested N for wool growth.