The influence of steam pelleting and grinding on the nutritive value of Canola rapeseed for poultry

In an attempt to explain the poorer performance and lower fat digestibility often encountered with Canola seed diets, maize and soya bean diets containing 20% Canola seed or an equivalent amount of added fat (8%) from maize oil, Canola oil, tallow or an animal—vegetable blend fat, were given to broiler chicks. Although significant differences in $\text{feed}\text{gain}$ ratios and fat digestibility were noticed, all diets promoted good growth, and dietary fat appeared to be well utilized.In a second experiment, to reinvestigate the effects of mash vs. pelleted diets, marked improvements were noted in performance, and especially in the digestibility of the fat from Canola seed diets, in response to steam pelleting. Examination of the mash diet revealed approximately 6% whole Canola seeds and other seeds at various degrees of pulverization.A third experiment compared Canola seed passed once or twice through a hammer mill, either by itself or mixed 50:50 (w/w) with maize, before being mixed with other dietary ingredients. Again, whole seeds were noted in the ground material. The Canola seed mixed with maize and ground once had 26% whole seeds, while the seed ground twice by itself had no whole seeds but many that were little better than cracked. All diets were given as mash or as steam crumbles. Marked improvements in weight gain and $\text{feed}\text{gain}$ ratios and fat digestibility were noted for the crumbled vs. the mash diets. It is obvious that some of the variable results reported for Canola seed can be related to fineness of grind of the material. The steam pelleting process results in sufficient pulverization, or breaking up of the seed, to allow for optimum performance with diets containing up to 20% Canola seed. Heating per se might also be an important consideration in steam pelleting. One can conclude that up to 20% Canola seed can be used in steam-pelleted diets based on maize and soya bean meal without altering broiler performance.     

Performance of guinea fowl fed hevea seed meal or cashew nut meal as a partial substitute for soya bean meal

Guinea fowl production is increasing in developing countries and has a crucial role in the fight against poverty. However, the feed cost is very high, especially the soya bean meal cost, and farmers cannot afford to buy commercial feed. Consequently, animals do not receive feed adapted to their nutritional needs and they exhibit poor performance. The aim of this paper is to partially substitute soya bean meal by local by-products, discarded, in abundant supply and not used in human nutrition. French Galor guinea fowl (Numida meleagris) and local African guinea fowl (150 birds per breed) were reared for 16 weeks and fed the same starter diet for the initial 4 weeks. From 4 weeks of age, experimental birds from each breed were randomly assigned to three grower isoproteic and isolipidic dietary treatments, each containing five replications (floor pens); each replication included 10 birds of the same breed. The guinea fowl of each breed were fed either control grower diet using soya bean meal as the protein supplement GS, or trial grower diet GN (soya bean meal supplement partially substituted by 15% cashew nut (Anacardium occidentale) meal) or trial grower diet GH (soya bean meal supplement partially substituted by 15% hevea seed (Hevea brasiliensis) meal). The results indicated that hevea seed meal contained a high content of n-3 polyunsaturated fatty acids (PUFAs) (21.2% of total fatty acids (FAs)). The use of hevea seed meal in guinea fowl grower diet was found to exert no adverse effect on growth performance and carcass yield. However, the use of cashew nut meal led to negative effects on performance like daily weight gain and feed conversion ratio. Therefore, cashew nut meal cannot be considered as a suitable partial substitute for soya bean meal in diets. The use of hevea seed meal led to a very low abdominal fat proportion and low blood triglyceride and cholesterol content. Additionally, inclusion of dietary hevea seed meal resulted in guinea fowl meat enriched in PUFAs, especially n-3 FAs, thereby significantly improving the nutritional value.     

Does the effect of pelleting depend on the wheat sample when fed to chickens?

Experimental comparisons of the nutritional value of different wheat cultivars commonly use feeds in meal form even though the large-scale broiler producers use steam pelleted feeds. The aim of this experiment was to examine the effect of steam pelleting on the performance, dietary N-corrected apparent metabolisable energy (AMEn), total tract dry matter retention (DMR), nitrogen retention (NR) and fat digestibility (FD) coefficients, and digestive tract development of broilers fed four different wheat samples in complete diets. Four European wheat samples, with different chemical composition and endosperm characteristics, were used in a broiler experiment. The wheat samples were milled through a 5 mm screen and four basal feeds containing 670 g/kg of each selected wheat sample were mixed. The basal feeds were then split into two batches and one of them was steam pelleted resulting in eight experimental diets. Each diet was fed ad libitum to eight pens of two male Ross 308 broilers from 10 to 24 days of age. Feeding pelleted diets improved (P<0.001) feed intake and weight gain, and daily water intake of the birds. Pelleting also improved dietary AMEn and FD (P<0.001) and DMR (P<0.05). An interaction (P<0.05) was observed between wheat samples and steam pelleting for NR. Steam pelleting improved (P<0.05) NR in the wheat sample with high starch and protein and hard endosperm but not in the rest of the wheat samples. Similar interactions (P<0.05) were also observed between wheat sample and steam pelleting for gain to feed (G : F) and water to feed (W : F) ratios. Pelleting improved G : F ratio the greatest in the wheat sample with high starch and protein and hard endosperm. Feeding the same wheat sample also decreased (P<0.05) W : F but only in the mash diets. Regardless of the wheat sample the values of dietary AMEn did not differ (P>0.05). Feeding different wheat types and pelleting did not (P>0.05) change the development of the gastrointestinal tract of the birds. The study showed that there were differences between four wheat samples when they were fed in pelleted complete feed, but no differences were observed when fed in mash form complete diets. Research on the interaction between pelleting and wheat chemical and quality characteristics is warranted.     

Meat meal in the diet of the early-weaned pig. I. A comparison of meat meal and soya bean meal

Seventy-two pigs, initially weighing 4–5 kg, were fed on wheat-based diets supplemented with soya bean meal and/or meat meal in two experiments each of 4 weeks' duration.In the first experiment, 0, 25, 50 or 100% replacement of soya bean meal protein supplement with meat meal was associated with a linear decrease in weight gains (341-280 g/d), a linear increase in feed conversion ratios (1.64–2.35) and a linear decrease in apparent digestibility of dry matter (80.1–73.4%). There was no change in the apparent digestibility of nitrogen.In the second experiment, bone meal was added to provide 0.80, 1.55 and 3.05% calcium in diets in which the protein supplements were either soya bean meal or meat meal. The addition of bone meal to the diets containing soya bean meal did not affect the performance of the pigs, but it caused a linear decrease in the apparent digestibility of dry matter, nitrogen and calcium. The addition of bone meal to the diet containing meat meal reduced the feed intakes of the pigs from 617 to 516 g/d and the weight gains from 414 to 324 g/d.Weight gains of pigs were similar when their diets contained soya bean meal or meat meal as the protein supplement in the second experiment when the calcium content of the diets was 0.8%. The meat meal included in the diet was manufactured from soft offal.     

Effects of milling and pelleting of maize,barley and wheat on their metabolizable energy value for cockerels and chicks

Metabolizable energy (ME) measurements were made on chicks and cockerels on diets comprising 770 g/kg of maize, barley or wheat milled to three moduli of fineness and given either as a mash or pelleted and crumbled.There were significant differences in ME among grains, between diet forms, and with age of bird. With chicks, ME (MJ/kg dry matter (DM)) of all three diets was lower for the mash form (13.98) than for the pelleted and crumbled (14.29), but with cockerels pelleting increased ME only with the wheat diets. The oil content of the grains was influenced by treatment. The pelleted diets contained more oil than those in mash and crumbled forms. These oil contents did not explain differences in the ME of the different treatments.Since there was no effect of modulus of fineness on ME, it was concluded that coarse milling was adequate and could reduce the cost of diet preparation.     

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.     

Black soldier fly as dietary protein source for broiler quails: apparent digestibility,excreta microbial load,feed choice,performance, carcass and meat traits

In order to expand with validated scientific data the limited knowledge regarding the potential application of insects as innovative feed ingredients for poultry, the present study tested a partial substitution of soya bean meal and soya bean oil with defatted black soldier fly (Hermetia illucens) larvae meal (H) in the diet for growing broiler quails (Coturnix coturnix japonica) on growth performance, mortality, nutrients apparent digestibility, microbiological composition of excreta, feed choice, carcass and meat traits. With this purpose, a total of 450 10-day-old birds were allocated to 15 cages (30 birds/cage) and received three dietary treatments: a Control diet (C) and two diets (H1 and H2) corresponding to 10% and 15% H inclusion levels, respectively (H substituted 28.4% soya bean oil and 16.1% soya bean meal for H1, and 100% soya bean oil and 24.8% soya bean meal for H2, respectively). At 28 days of age, quails were slaughtered, carcasses were weighed, breast muscles were then excised from 50 quails/treatment, weighed, and ultimate pH (pHu) and L*, a*, b* colour values were measured. Breast muscles were then cooked to assess cooking loss and meat toughness. For the digestibility trial, a total of 15 28-day-old quails were assigned to the three feeding groups. The excreta samples were subjected to chemical and microbiological analysis. The same 15 quails were then simultaneously provided with C and H2 diets for a 10-day feed choice trial. Productive performance, mortality and carcass traits were in line with commercial standards and similar in all experimental groups. With the exception of ether extract digestibility, which was lower in H1 group compared with C and H2 (P=0.0001), apparent digestibility of dry matter, CP, starch and energy did not differ among treatments. Microbial composition of excreta was also comparable among the three groups. Feed choice trial showed that quails did not express a preference toward C or H2 diets. Breast meat weight and yield did not differ among C, H1 and H2 quails. Differently, the inclusion of H meal reduced meat pHu compared with C. In conclusion, this study demonstrated that H. illucens larvae meal can partially replace conventional soya bean meal and soya bean oil in the diet for growing broiler quails, thus confirming to be a promising insect protein source for the feed industry. Further research to assess the impact of H meal on intestinal morphology as well as on meat quality and sensory profile would be of utmost importance.     

Effects of feeding intact,ground and/or pelleted rapeseed on nutrient digestibility and growth performance of broiler chickens

ABSTRACT

In this study, the effect of grinding or pelleting of rapeseed on the digestibility, apparent metabolisable energy (AME_N), growth performance and gizzard weight of broiler chickens was evaluated. In Exp. 1, four treatments were tested (240 broiler chickens, 20 replications, 3 birds per cage). Birds received either a basal diet or were fed with rapeseed of different sized particles (fine, medium and coarse ground, respectively). In Exp. 2, 10 treatments were assessed (360 chickens, 12 replications, 3 birds per cage), where five different diets (a basal diet and four diets with intact rapeseed, fine ground, medium ground or coarse ground rapeseed, respectively) were fed non-pelleted or pelleted. In Exp. 3, two treatments were compared (224 broiler chickens, 14 replications, 8 birds per floor pen): fine ground rapeseed (FG) and intact rapeseed (IS). Compared with medium and coarse ground rapeseed, fine grinding increased in Exp. 1 the AME_N of rapeseed and the precaecal digestibility (PD) of dry matter and ether extract (EE) (p < 0.05). In Exp. 2, the content of AME_N and the PD of EE and crude protein (CP) increased as the degree of grinding increased when diets were not pelleted (p < 0.01). In contrast, the significantly highest values for these parameters were measured after pelleting without effect of grinding, resulting in a significant interaction between pelleting and grinding (p < 0.001). In Exp. 3, performance of chickens was not affected by dietary treatments, but gizzard weight and the PD of CP were higher when IS were included in the diet (p < 0.05). The results suggested that fine grinding may be used to increase the feeding value of full-fat rapeseed for broiler chickens. Nevertheless, pelleting of diets with rapeseed seemed to be much more effective in the reduction of particle size than grinding.     

Effects of diets differing in protein source and technical treatment on digestibility,performance and visceral and biochemical parameters of fattening pigs

The aim of the experiment on 100 cross-bred barrows was to compare commercial diets for fattening pigs based on either soya bean meal (SBM) imported from non-European countries with diets based on a mixture of locally produced rape seed meal, distillers’ dried grains with solubles and soya beans as main protein sources. In addition, these both types of diets were processed by two different technical feed treatments, i.e. coarse grinding without hydrothermal treatment or fine grinding and pelleting. With only few exceptions, nutrients of the diet without SBM were more digestible (p < 0.05) resulting in a higher metabolisable energy (ME) content. Fine grinding and pelleting increased also the ME content and the nutrient digestibility with the exception of crude fibre. Higher feed intake of animals that fed diets without SBM (p < 0.01) resulted in higher average daily gain (p < 0.01). However feeding this diet, the higher digestibility was not reflected in a decreased feed-to-gain ratio (FGR), but fine grinding and pelleting reduced FGR (p < 0.001). A higher pH value and a lower DM content of caecal chymus were detected in animals that received coarsely ground feed (p < 0.05). Animals that fed finely ground and pelleted feed had higher slaughter and relative liver weights and higher blood cholesterol concentrations (p = 0.040). The urea concentrations of blood were lower (p = 0.019) after feeding diets without SBM. In conclusion, SBM imported from non-European countries can be replaced by alternative local protein sources without compromising digestibility or performances of animals. Although fine grinding and thermal treatment particularly seemed to be advantageous for digestibility and performance, the possible risk of development of stomach lesions should be considered.     

Use of unextracted sunflower seeds as a protein source

Substitution of unextracted sunflower seeds for either 0, 25, 50 or 100% of the soya bean meal in pig diets produced no significant differences in digestible energy or apparent nitrogen retention. However, all diets containing unextracted sunflower seeds had significantly higher digestible nitrogen than the diets containing soya bean meal as the protein source. Replacement of 25% of the soya bean meal with unextracted sunflower seeds produced the greatest increase in digestibility. Rate and efficiency of gain in rats were used to evaluate the effects of autoclaving unextracted sunflower seeds at 115°C with 1.05 kg/cm² pressure for 0, 5 or 10 minutes. Rats fed on the basal maize-soya bean meal diet gained significantly faster and more efficiently than the rats fed on the diets containing the sunflower seeds. An increase in heating time of the sunflower seeds produced a significant reduction in rate and efficiency of rat gain.     

Influence of micronization (fine grinding) of soya bean meal and full-fat soya bean on the ileal digestibility of amino acids for broilers

A trial was conducted to test the effect of fine grinding (micronization) of soya bean meal (SBM) and full-fat soya bean (FFSB) on coefficient of ileal apparent digestibility (CIAD) and coefficient of ileal true digestibility (CITD) of amino acids in 23-day-old broilers. A completely randomized block design with four treatments arranged factorially (SBM and FFSB; micronized and ground) and six replicates (eight broilers per treatment) was used. Mean particle size (MPS) was 47 and 41 μm for micronized SBM and FFSB and 881 and 778 μm for ground SBM and FFSB, respectively. The four diets were based on maize starch and sucrose with the soya product tested as the sole source of dietary crude protein (CP, 200 g/kg). In addition, a nitrogen-free diet was formulated to estimate the basal ileal endogenous losses of the amino acids. Broilers were fed a commercial pelleted maize-SBM diet from 1 to 19 days of age and, then, their respective experimental diets in mash form from 20 to 23 days of age. Broilers fed SBM had higher CIAD of organic matter, CP, arginine, leucine, methionine and valine (P<0.05) and tended to have higher CIAD of threonine (P<0.10) than broilers fed FFSB. In addition, broilers fed SBM had higher CITD of CP (P<0.05), leucine, methionine and valine (P<0.01) than broilers fed FFSB. Particle size did not affect the ileal digestibility of CP or of any of the essential amino acids. It is concluded that broilers fed soya bean meal had higher ileal digestibility of amino acids than broilers fed full-fat soya bean and that fine grinding of the soya products did not affect amino acid digestibility.     

House fly larvae meal grown on municipal organic waste as a source of protein in poultry diets

House fly larvae (Musca domestica L.) grown in the residues of municipal organic waste were evaluated as a protein concentrate in practical diets for poultry. Seventy-two broiler-type chicks were alloted within 12 groups. Quadruplicate groups each received the following dietary treatments: a control diet containing soya bean meal alone, or two diets in which either 12% of the supplementary protein was provided by fly larvae meal or 9% by fish meal. The chicks were fed during the first four weeks of life with isocaloric and isoproteic diets and the results showed no significant differences in body weight gain (P > 0.05) or food conversion efficiency (P > 0.05), the larvae meal diet being intermediate to the other two.     

An initial evaluation of camel and cow manures as dietary ingredients in pelleted feed for blue tilapia (Oreochromis aureus)

Camel and cow manures were evaluated as dietary components in pelleted feed for male tilapia over a 12 week period. Seven isonitrogenous (35% crude protein) and isocaloric (4·00 kcal/g gross energy) diets were prepared. Each manure was included in the diets at 10, 20 and 30%. A control diet containing neither of the two manures was used. The best survival rate, growth performance and feed utilization efficiency values were achieved by the control diet. Diets containing 10 or 20% camel manure or 10% cow manure gave relatively good results. Higher inclusions of the two manures significantly (P < 0·05) suppressed growth. It is recommended that camel and cow manures could be included in pelleted feeds of tilapia at levels of up to 20 and 10% respectively.     

The nutritive value of Tower rapeseed meal for swine

Two experiments involving 144 Yorkshire × Lacombe gilts, with an average initial weight of 20 kg, were conducted. In Experiment 1 the gilts were allotted to a control diet containing soya bean meal (SBM) or to diets in which either 50% or all of the supplementary protein was provided by Tower rapeseed meal (RSM). In the second experiment the two diets had either SBM or Tower RSM as the supplementary protein source. In a third diet Tower RSM was supplemented with sufficient lysine to equal the calculated available lysine level of the SBM control diet. In Experiment 1, gilts given the SBM diet grew from 20 to 60 kg significantly faster (P<0.01), and had better feed conversion efficiency (P<0.01), than those given the RSM diets. A 50% replacement of SBM by Tower RSM gave intermediate results. Partial or total replacement of SBM by Tower did not significantly affect the growth rate or feed conversion efficiency of the gilts when growing from 60 to 100 kg liveweight. Serum triiodothyronine (T3) and thyroxine (T4) concentrations of the gilts at 100 kg were lower in pigs fed on the RSM diets but the differences were not significant. In the second experiment, total replacement of SBM by Tower RSM, with or without the addition of lysine, significantly (P<0.001) reduced growth rate and feed conversion efficiency during the growing period (20–60 kg) but did not significantly affect performance during the finishing period (60–90 kg). Serum T3 concentration was not significantly affected by the addition of Tower RSM to the diet but T4 concentrations were significantly reduced (P<0.01). None of the carcass parameters studied were significantly affected by the addition of Tower RSM to the diets.     

Pelleting and extrusion can ameliorate negative effects of toasting of rapeseed meal on protein digestibility in growing pigs

Toasting time (TT) of rapeseed meal (RSM), the diet processing (DP) method and the interaction between both on the apparent CP digestion along the gastrointestinal tract and the apparent ileal digestibility (AID) of amino acids of growing pigs were investigated. The experiment consisted of a 3×3 factorial design of TT of RSM (0, 60 and 120 min) and DP method (mash, pelleting and extrusion). In total, 81 boars with a starting BW of 20 kg were euthanized 4 h after their last feeding. The gastrointestinal tract was dissected and the small intestine divided in three sections of similar length. Samples were collected from the stomach, 1.5 m from the ends of each of the three sections of the small intestine, and the rectum. The apparent digestibility (AD) of CP for each of the small intestine sections was used to calculate the rate of CP digestion. Increasing the TT of RSM resulted in lower protein solubility, lower lysine/reactive lysine contents and higher protein denaturation, indicative of the occurrence of protein aggregation and Maillard reactions. There were significant effects (P⩽0.01) of TT on the AD of CP in the different sections of the gastrointestinal tract. The rate of CP digestion of the 0 min toasted RSM diets was 23% and 35% higher than that of the 60 and 120 min toasted RSM diets, respectively. There was a significant interaction (P=0.04) between TT and DP for the AID of CP. Although pelleting of the 0 and 60 min toasted RSM diets did not change the AID of CP with respect to the mash diets, pelleting of the 120 min toasted RSM diet increased the AID of CP by 9.3% units. Extrusion increased the AID of CP of the 0 and 60 min toasted RSM diets by 3.4% and 4.3% units with respect to the mash diets, whereas extrusion of the 120 min toasted RSM diet increased the AID of CP by 6.9% units. Similar positive effects of pelleting and extrusion were obtained for the AID of lysine and reactive lysine, especially in the diets with higher TT. In conclusion, processing (pelleting and extrusion) of RSM containing diets can ameliorate the negative effects of RSM toasting on protein and amino acid digestibility; these effects were larger for the RSM toasted for longer times.     

Influence of source and micronization of soya bean meal on growth performance,nutrient digestibility and ileal mucosal morphology of Iberian piglets

The effects of inclusion in the diet of different sources of soya bean meal (SBM) on growth performance, total tract apparent digestibility (TTAD) and apparent ileal digestibility (AID) of major dietary components and mucosal ileum morphology were studied in Iberian pigs weaned at 30 days of age. From 30 to 51 days of age (phase I), there was a control diet based on regular soya bean meal (R-SBM; 44% CP) of Argentina (ARG) origin and five extra diets in which a high-protein soya bean meal (HP-SBM; 49% CP) of the USA or ARG origin, either ground (990 μm) or micronized (60 μm), or a soya protein concentrate (SPC; 65% CP) substituted the R-SBM. From 51 to 61 days of age (phase II), all pigs were fed a common commercial diet in mash form. The following pre-planned orthogonal contrasts were conducted: (1) R-SBM v. all the other diets, (2) SPC v. all the HP-SBM diets, (3) micronized HP-SBM v. ground HP-SBM, (4) HP-SBM of ARG origin v. HP-SBM of US origin and (5) interaction between source and the degree of grinding of the HP-SBM. Dietary treatment did not affect growth performance of the pigs at any age but from 30 to 51 days of age, post weaning diarrhoea (PWD) was higher (P<0.001) and the TTAD and AID of all nutrients were lower for pigs fed the R-SBM diet than for pigs fed the HP-SBM or the SPC diets. However, no differences between the HP-SBM and the SPC containing diets were detected for any trait. The TTAD of organic matter (P=0.07) and gross energy (GE) (P=0.05) tended to be higher for the micronized HP-SBM than for the ground HP-SBM and that of GE was higher (P<0.05) for US meal than for the ARG meal. Pigs fed R-SBM had lower villus height (P<0.01) than pigs fed HP-SBM or SPC but no differences in ileal mucosal morphology were detected between SPC and HP-SBM containing diets. It is concluded that feeding the HP-SBM or SPC-reduced PWD and improved nutrient digestibility and ileal morphology as compared with feeding the R-SBM, but had no effect on pig performance. The inclusion in the diet of added value soya products (micronized SBM or SPC) in substitution of the R-SBM increased the TTAD of all nutrients and reduced PWD but had no advantage in terms of growth performance over the use of ground HP-SBM.     

Effects of inclusion with blue lupins (Lupinus angustifolius) in broiler diets and enzyme supplementation on production performance, digestibility and dietary AME content

An experiment with broiler chickens was conducted to study the effect of inclusion of blue lupins and exogenous enzyme to broiler diets on the apparent metabolisable energy (AME), digestibility and performance. Two basal diets were formulated: a non-lupin diet A based on soya bean meal and maize, and a diet B where parts of soya bean meal and maize were substituted with blue lupin (200 g/kg). The two basal diets were fed either alone or, for diet B in combination with different enzyme preparations (Bio-Feed Plus, lactase, two galactanases (Gal-I and Gal-II)). The experiment was performed in battery cages with 648 male broiler chickens, where eight experimental diets were fed to the chickens from 7 to 21 days of age and weight gain and feed intake were measured during the period. At the end of the experiment, three chickens from each pen were slaughtered and the content from jejunum and ileum was separately collected and pooled and used for measurement on intestinal viscosity. For measurements of the apparent metabolisable energy and the apparent digestibility, excreta were collected at 22–24 days of age and ileal contents collected at 25–26 days from the remaining chickens.

Substitution of soya bean meal and maize with blue lupin depressed weight gain (9%) and feed conversion ratio (12%) significantly. Feed intake of the lupin-based diets was not decreased. The protein in lupin was digested to the same extent as the protein from soya bean meal, the coefficient of ileal apparent digestibility being on average 0.75. However, the high content of the non-starch polysaccharides (NSP; 450 g/kg) in lupin depressed the apparent digestibility of the organic matter by approximately 10%. The AME_n of the non-lupin diet was 14.01 MJ/kg dry matter (DM) compared to a value of 13.11 MJ/kg DM in the lupin control diet. Improvements in the measured parameters were seen with some of the enzymes. Gal-I, and Gal-II in combination with lactase were the most efficient enzymes concerning improvement in AME_n and performance. Weight gain was increased by 3.5–5.5% by addition with these enzymes. Gal-I increased the AME_n significantly to 13.65 MJ/kg, a value not significantly different from the AME_n of the non-lupin diet. There was no effect of addition with the different enzymes on the coefficients of apparent digestibility of organic matter measured in the ileum, whereas addition with Gal-I to the lupin diet increased the apparent digestibility of organic matter over the total tract by 3%. The mode of action of the galactanases has been to hydrolyse the galactan in the NSP cell wall of lupins to galactose and dimers of galactose, which are energy-yielding to poultry. From the results obtained, it can be indicated that Gal-I increased the energy utilisation of the lupin-based diet, confirmed by the improved AME_n content and performance.     

Ammonia and sodium hydroxide treatment of wheat straw in diets for fattening steers

The effects of treating Neepawa wheat straw with anhydrous ammonia (35 kg t^?1), sodium hydroxide (50 kg t^?1) and pelleting were evaluated in two experiments. The diets consisted of 51% rolled barley, 40% straw, 4% rapeseed meal, 2% tallow, plus minerals and a vitamin supplement. Straw was treated as follows: (1) shredded into 2.0-cm lengths; (2) shredded into 0.64-cm lengths and pelleted; (3) ammoniated and shredded; (4) ammoniated and pelleted; (5) sodium hydroxide and pelleted; (6) ammoniated, sodium hydroxide and pelleted.Apparent digestibility was measured with six steers per treatment. Pelleting had no effect on organic matter (OM) digestibility, but decreased neutral detergent fibre (NDF) and cellulose digestion. Respective increases for OM and NDF digestibility following chemical treatment of the straw were as follows: ammoniation — 15 and 17%; sodium hydroxide — 4 and 13%.The six diets were given to 144 Hereford steers (240 kg) for 92 days in the second experiment. Feed consumption ranged from 8.51 to 10.39 kg day^?1 for diets 1 and 4, and body weight gains ranged from 0.83 to 1.26 kg day^?1 for diets 1 and 6, respectively. Respective increases for intake, gain and feed efficiency compared to untreated shredded straw were as follows: pelleting — 11, 34 and 17%; ammoniation — 12, 36 and 17%. Sodium hydroxide treatment prior to pelleting improved intake, gain and feed efficiency by 5, 10 and 5%, respectively. There was no evidence of additive effects between ammoniation and either pelleting or alkali treatment, though treatment with sodium hydroxide prior to pelleting did result in the highest gains and feed efficiency.     

饲料鱼粉、菜粕比例对异育银鲫生长和饲料利用的影响

通过在饲料中配制不同鱼粉和菜粕比例,探讨利用菜粕蛋白替代鱼粉对异育银鲫（Carssius auratus gibelio）的生长和饲料利用的影响。饲料中菜粕蛋白替代鱼粉蛋白的比例分别为 0、20%、40%、60% 和80%。实验结果表明,当饲料中菜粕蛋白比例高于40%时,异育银鲫的生长显著下降（P0.05）,对摄食率影响不明显（P0.05）。在80%替代水平下,干物质和蛋白质的消化率最低,能量消化率在40%替代水平最低。饲料转化效率在20%蛋白替代后明显下降（P0.05）。蛋白质和能量储积率在40%蛋白替代后明显下降（P0.05）。在40%菜粕蛋白下,鱼体能量和脂肪含量最高。鱼体蛋白质在60% 和80% 菜粕蛋白时最低,脂肪在20% 菜粕蛋白时最高。因此饲料菜粕蛋白的水平不超过20%（干物质含量约17%）不会影响异育银鲫的生长和饲料转化。       

Nutritive value of spruce muka (foliage) for the growing chick

Three experiments were conducted with broiler type chicks to determine the nutritive value of spruce (Picea glauca) muka for growing birds to 4 weeks of age. Up to 10% of a diet of maize, soya bean meal and fishmeal was replaced with muka, alfalfa meal or cellulose. Growth, feed consumption, mortality and organ: body weight ratios were examined.The addition of muka, untreated or steam distilled, to the basal diet reduced growth except in the case of 2.5% steam distilled muka, for which growth was comparable to that for the basal diet. When the protein content of the basal diet was reduced, up to 5% untreated or steam distilled muka could be introduced without significant growth depression. However, at the 10% level, growth depression was significant (P < 0.05). Pelleting the supplemented diets significantly stimulated growth.Feed consumption was usually depressed by the addition of the supplements to the basal diet. Mortality was not influenced by treatment. Organ: body weight ratios were not influenced by treatment × sex interactions. Muka, cellulose or alfalfa, each incorporated as 10% of the diet, did not influence the organ: body weight ratio of the heart, proventriculus, caeca, spleen or gall bladder. All the experimental feeds increased the size of the remaining components of the digestive tract, as well as the liver and pancreas.