Aflatoxins (AF) are secondary fungal metabolites mainly produced by Aspergillus flavus and Aspergillus parasiticus. Aflatoxin contaminated feedstuffs (ACF) are a major problem in developing countries, where that most of poultry feedstuffs contain low levels of different kinds of AF; particularly due to inappropriate conditions of transportation and storage. This could cause silent economical losses in poultry production. The number of studies who have investigated the effects of ACF in broiler nutrition is much; however, little of them focused on low concentrations of AF. Moreover, it has been suggested that negative effects of AF on broiler performance are both dose- and time- dependent (Leeson et al. , 1995). In this study, the effects of long-term low level administration of AFB1 into diet (0 to 28 days of age), on performance, blood enzymes and some organs weight of male broiler chickens have been investigated.

Wheat grain is a major ingredient in broiler diets in many countries, and due to its high protein and starch content, it is considered to be a good source of nutrients for broilers. But wheat contains 5 to 8 percent non starch polysaccharides (NSP), pentosans, which may be impair nutrient digestibility and growth performance (Carre and Brillouet, 1986). Several studies have shown that, among the nutrients, fat digestion suffers the most pronounced impairment due to high digesta viscosity (Choct and Annison, 1992). It is suggested that to reduce adverse effects of anti nutritional factors content in wheat, diet supplements with enzyme. The effect of dietary supplementation of xylanse enzyme on growth performance is depended upon the amount and fat type (Langhout, et al. 1997). Different fat sources are usually added to broiler diets to increase energy concentration and to improve productivity. This study was carried out to determine effect of xylanase enzyme and fat type on growth performance and intestinal viscosity of broiler fed wheat based diet.

The most practical method for increasing the energy concentration in poultry diets has been by the addition of fats and oils (Hill and Dansky, 1954). Now a days use of fats because of increasing of the energy, improving growth and physical quality of diet have special importance. Fats rich in unsaturated fatty acids are better digested and absorbed than saturated fats (Danicke 2001). Studies with rats and broilers have reported that unsaturated vegetable oils produce lower fecal energy losses and, consequently higher metabolism energy that animal fats (Zollitsch et al, 1997). This higher metabolism energy of unsaturated fat could be expected to cause higher fat deposition because the additional energy could be stored as triglycerides (TG) in adipose tissue of fat depots. Opposite of this results Crespo and Steve (2002) observed that among broilers fed diets with added fat (tallow, olive, sunflower, and linseed), linseed oil had less abdominal fat (AF) than those fed tallow. The objective of this study was determination of effects of different fat sources on performance, blood metabolites and abdominal fat of broiler chickens.

Feed-borne antibiotics have been used since early of 1950’s in feed as a first primary to control of disease and more recently as a growth promoter and improve feed conversion efficiency in the poultry industry. Two of the more popular feed grade, spectrum antibiotics utilized within the poultry industry includes Virginiamycin (VIR) and Bambermycin (BAM) (Parks et al, 2001). Studies with broiler were indicated that probiotic bacteria are an alternative to antibiotics to be used extensively as a growth promoter in form animals (Green and Sainsbury, 2001). The aim of this study was to determine the effects of antibiotic (Virginiamycin) and probiotic (Saccharomyces cerevisiae ) and their interaction on broiler performance and carcass yield.

The literature and recent research (Scott 2002) demonstrated that wet feeding may overcome limitation in feed intake of wheat-based diets, thereby increasing growth rate. However, there have been inconsistent effects on feed conversion ratio (FCR). Thus it is important to differentiate whether differences in feed efficiency can be explained by monitoring nutrient retention. This experiment was conducted to study the effect of two types of wheat ((Durum, HRS (Hard Red Spring)) on broiler performance and nutrient digestibility, when diet were offered in a wet or dry form.

Maize is the principal energy source in most poultry diet in developing countries. As the cultivating of maize is limited in Iran, annually a large amount of maize is imported. Broken rice (BR) is a major cereal by-product for animal feeding in rice-growing countries. The annual production of rice paddy in Iran is about 2 million tonnes. After milling of paddy, broken rice is available for utilization in animal diet. BR consists of 40 to 80 g/kg of rice paddy. It contains good sources of protein (100-110 g/kg), fat (60-110 g/kg), carbohydrate, fibre (20-50 g/kg). Due to mixing with bran and hull the chemical composition of BR varies in different samples. In some part of the country the price of this ingredient is lower than maize. The objective of the present experiment was to evaluate the effect diets containing different levels of BR on performance of broiler chicks from 1 to 8 weeks of age.

Holstein-Friesian is dominant cattle breed in Hungary, so it plays an important role in beef production. That’s why it is important to know more about slaughter results and meat quality of this breed. As only little information is available in this topic Szabó et al. (2002) and Lengyel et al. (2003), the purpose of the study was to investigate some slaughter parameters and composition of various muscles of young bulls slaughtered at different ages.

It has been shown that rumen protozoa have a higher content of conjugated linoleic acid (CLA) and trans-vaccenic acid (TVA) than rumen bacteria, suggesting that protozoa may make a significant contribution to TVA and CLA flow from the rumen (Devillard et al., 2004). As part of a project studying the role of protozoa in rumen bio hydrogenation, this study was carried out to determine the effect of the absence of protozoa in the on ruminal biohydrogenation, microbial diversity and the fatty acid composition of lamb muscle.

Information from cattle passports and abattoirs now make it possible to add breed type, sex category and age at slaughter to records of carcase weight, fatness and conformation. The objective of this study was to investigate relationships between slaughter age, carcase weight, fatness and conformation in crossbred beef cattle using Limousin X steers as an example.

Since the announcement that mature cull cows can re-enter the human food chain, there is increasing interest from commercial producers in devising systems that finish suckler cows to an acceptable degree of fatness and conformation score. A detailed understanding of the relationships between cow liveweight (LW) and condition score (CS) is necessary if cows are to be grown and finished to achieve optimum carcass weights and marketed at optimum commercial returns. Previous work conducted over 20 years ago with traditional UK suckler cow types at that time, showed that for every one unit change in suckler cow CS the corresponding change in cow LW ranged from 61 – 110 kg with an average value of 95.6 kg (Wright and Russel, 1984) for cows that ranged in average LW from 434 – 560 kg. However, little information is available on the relationships between suckler cow LW and CS in suckler cow genotypes present in the UK today. The objective of this study was to estimate the relationship between suckler cow LW and CS in modern Aberdeen Angus cross (AAx) and Limousin cross (LIMx) suckler cows.

Information from cattle passports and abattoirs now make it possible to add breed type, sex category and age at slaughter to records of carcase weight, fatness and conformation. The objective of this study was to examine the performance of Holstein Friesian bulls in commercial beef production.

Rumen microorganisms change feed protein characteristics and convert some feed protein to microbial protein. Determination of feed protein degradability coefficients and acid detergent insoluble nitrogen (ADIN) content is necessary for calculation of metabolisable protein (MP) content of feedstuffs. Absence of true information about these coefficients of native feedstuffs is a prime problem for diet formulation in Iran. The objective of this study was to determine the protein degradability coefficients of some native feedstuffs and compare them with AFRC (1995) data (the system now being used in Iran) in the feeding of lactating cows in terms of intake, milk yield and milk composition.

Tannins are secondary plant compounds frequently encountered in tropical feeds. They are known to complex with proteins, thus reducing the availability of protein to ruminants. Tannin determination is thus a crucial factor when estimating the feed quality of tropical plants. Bovine serum albumin (BSA), which is commonly used in tannin binding assays has the drawbacks of being a non-plant protein and requires a rather low pH (4.9, iso-electric point of BSA) for complex formation with tannins. Papain is a commercially available pure protein from Carica papaya that may be a suitable alternative. This study evaluates papain as a test protein in a tannin binding assay in comparison to BSA by determining the specific protein precipitation capacity (sPPC) of the tannin rich plants, Salix alba (salix) and Rhus typhina (sumach). Salix and sumach leaves contain exclusively condensed tannins and hydrolysable tannins respectively.

Problems with current ruminal starch degradation estimates (e.g. in sacco technique - excessive initial losses; rate of passage studies - expense and time consuming) render them unsuitable for routine use. These together with inaccurate starch assays (Krystallidou and Mould, 2004) and inappropriate rumen outflow kinetics, combine to produce a questionable data. Considering the role of starch in the nutrition of high producing dairy cows and its impact on the rumen fermentative environment, a system that accurately predicts both the extent and site of starch degradation would be of strategic importance. It was hypothesised that starch degradation in vitro is likely to be similar if not identical to that of the rumen. Thus starch outflow kinetics can be calculated using the difference between expected (in vitro ) and assayed rumen levels following a discrete starch meal. Further, the administration of an appropriate marker, with outflow kinetics similar to starch, will allow effective ruminal starch degradation to be estimated from in vitro data, using intact animals offered different feeding regimes

Wheat is grown because it provides grains for human food and straw that can be fed to ruminants. In recent years, wheat varieties that have shorter, thicker stems for supporting a higher grain yield have been a popular choice by farmers. Straw derived from these wheat varieties has a higher lignin content. Several methods to attempt to improve the nutritional value of wheat straw have been tested without much success, due mainly to the reduced palatability of chemically treated straw, the high cost of the treatments or to the increased labour required to perform the treatment. It has already been shown that some Pleurotus species (white rot fungi of the Basidiomycota) can selectively degrade lignin in wheat straw, making the cellulose and hemi-cellulose move available for digestion by ruminants. Selecting a Pleurotus variety which could be induced to produce edible fruit bodies could result in a profitable enterprise and thus offset the increased costs of a biological treatment. The ability of five strains of Pleurotus to increase the digestibility of wheat straw has been investigated in this study.

Agricultural by-products like cereal straws and sugarcane bagasse are high in lignocellulose. Sugarcane bagasse contains more than 60% of its dry matter in the form of cellulose and hemicellulose but its degradability is very low. One of the main reasons for this low degradability is the presence of lignin which protects carbohydrates from attack by rumen microbes (De La Cruz, 1990). The main effect of steam treatment is to increase feed intake, overall digestibility and live-weight gain which is achieved because of the extensive destruction of cell wall and hemicellulose hydrolysis which increases soluble sugars and makes cell wall more degradable. The aim of this study was to assess the effect of steam pressure and reaction time on physico-chemical and bio-utilization of sugarcane bagasse.

Soya-bean meal (SBM) proteins are extensively degraded in the rumen, and various physical and chemical treatments have been used to decreased its extent of ruminal degradation (Sadeghi et al., 2005), thereby increasing its content of metabolizable protein. As reported by Urbain (1986), gamma irradiation can affect proteins by causing conformational changes, formation of protein free radicals, and recombination and polymerization reactions. To our knowledge, no information is available concerning effects of gamma irradiation on ruminal protein degradation and type of SBM true proteins that leave the rumen undegraded. The main objectives of present study were to monitor fate of gamma irradiated SBM true proteins in the rumen by using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) methodology.

Sheep and goats browse c. 260 of leguminous species in Yucatán, Mexico (Flores Guido et al., 2003). Forage trees are a feed resource around the world. However its use is currently limited due to their content of antinutritional factors such as tannins and scarce data on their biological activity. The objective of the present work was to determine the biological activity (protein binding capacity) of condensed tannins extract from Leucaena leucocephala, Acacia pennatula, Lysiloma latisiliquum and Piscidia piscipula.

The efficiency of use of dietary nitrogen (N) in cattle is influenced by the rate of degradation of dietary protein to peptides, amino acids and ammonia and the concomitant rate of assimilation of these nitrogenous products by rumen micro-organisms for their protein synthesis. The latter depends heavily on fermentable energy availability (FME). Ammonia that is not assimilated is absorbed across the rumen wall and is mostly excreted. This excretion represents inefficient use of dietary N. The stable isotope 15N provides a useful means of making quantitative estimates of N utilisation in ruminants. However, owing to technical challenges associated with implementation of tracer dilution methods, measurement of 15N content in biological materials and cost of 15N-labelled materials, there have been relatively few studies using 15N in larger animals. Our objective was to develop and evaluate tracer dilution methods using 15N that would be appropriate for studying the efficiency of use of the N in perennial ryegrass silages when used for feeding cattle.

Previous work (Hyslop, 2005) has shown that alternative algebraic calculation methods give similar estimates of total tract mean retention times (TMRT) in ponies given complete pelleted diets. This similarity in TMRT estimates across calculation methods remains to be confirmed with other dietary constituents. This study's objective was to compare liquid, concentrate and forage TMRT estimates using alternative algebraic calculation methods.