Comparative sulfur analysis using thermal combustion or inductively coupled plasma methodology and mineral composition of common livestock feedstuffs

The objective of this study was to compare the use of thermal combustion (CNS) and inductively coupled plasma (ICP) to measure the total S content in plant-, animal-, and mineral-based feedstuffs, and to provide concentrations of other macro- and micro-minerals contained in these feedstuffs. Forty-five feedstuffs (464 total samples) were obtained from suppliers as well as swine feed and pet food manufacturers throughout the United States. Mineral data from IPC analysis were summarized on a DM basis using sample mean and SD, whereas the comparison of total S content between CNS and ICP was examined by bivariate plot and correspondence correlation. Analyses of a wide range of feedstuffs by CNS and ICP for total S were comparable for all but a few feedstuffs. For potassium iodide and tribasic copper chloride, ICP estimated total S to be lower than when analyzed by CNS (bias = 2.51 +/- 0.15 SE, P < 0.01). In contrast, for defluorinated phosphate and limestone, ICP estimated total S to be greater than when analyzed by CNS (bias = -1.46 +/- 0.51 SE, P < 0.01). All other samples had similar estimates of total S, whether analyzed by CNS or ICP. As expected, S composition varied greatly among feedstuffs. For total S, plant-based feedstuffs generally had lower total S compared with animal-based feedstuffs, whereas minerals supplied in sulfate form had the greatest concentration of total S. In addition to total S, mineral composition data are provided for all feedstuffs as obtained by ICP analysis. Within specific feedstuffs, mineral composition was quite variable, potentially due to low concentrations in the feed-stuff causing high mathematical variation or due to the source of feedstock obtained. In general, analyzed values of P were similar to previous tabular values. These data provide feed formulators a database from which modifications in dietary minerals can be accomplished and from which mineral requirements can be met more precisely to reduce losses of minerals into the environment.     

Dispensing law and sale of animal feed

For the veterinarian, drug sale is generally permitted by his licence of drug dispensing. According to the law on animal feed, feedstuffs are not regarded as drugs and thus they are not licensed to be sold by veterinarians. Drugs, however, may only be released for the treatment of individual animals, which are previously examined by the vet. The sale of animal feed is not regarded as part of veterinary practice. Only in case of a registered additional business, a veterinarian is allowed to sale feedstuffs. Dietetic animal feedstuffs are also regulated by the Animal Feed Act. Dietetic drugs, however, are regulated by the Drug Act and are strongly to be delineated from dietetic feed. Thus, the term "dietetic" alone does not automatically give any legitimatization for a sale of feedstuffs in veterinary practice.     

Digestibility and availability of amino acids from feedstuffs for pigs: a reviewDigestibilité et disponibilité des acides amines des aliments destinés au porcVerdaulichkeit und Verfügbarkeit von Aminosäuren in Schweinefutter

Measurements of the digestibility and availability of amino acids in feedstuffs should predict the ability of feedstuffs to supply amino acids to pigs in forms suitable for protein synthesis. Some of the methods available for such measurements are discussed; further work is needed to establish their reliability for predicting production responses to feedstuffs. At present the nitrogen balance technique appears to be the most useful, though indirect, method of evaluating feedstuffs as sources of amino acids.     

Biochemical Phenotypes of Salmonella Livingstone Isolated from Humans,Animals and Feedstuffs in Sweden

Salmonella Livingstone is occasionaly isolated from humans, animals and feedstuffs in Sweden. To follow the spread of infection and trace the source of isolates, adequate typing methods are needed. We have developed an automated typing system based on biochemical fingerprinting of bacteria (the PhP system) for typing of different Salmonella serotypes. The system measures the kinetics of various biochemical reactions of bacteria grown in liquid medium in microtiter plates and uses numerical techniques to identify biochemical phenotypes (BPTs) among the tested strains. In the present study we used a set of 16 highly discriminatory tests to differentiate strains of Salmonella of serotype Livingstone and evaluated the system for its discriminatory ability using a collection of 34 unrelated human isolates of S. Livingstone. We also used the system to investigate BPTs of 45 Livingstone strains isolated from animals and feedstuffs in Sweden between 1987 and 1991. Altogether 19 different BPTs were found among human isolate giving a diversity index (Di) of 0.930. In contrast, most strains isolated from animals and feedstuffs in Sweden belonged to 2 dominating BPTs (Di = 0.704). One of these contained 17 strains mainly isolated during 1992 whereas the other contained 18 strains isolated between 1987 and 1991. None of the Swedish human isolates were identical to those of animals and feedstuffs. These findings suggest that 2 different BPTs of Salmonella Livingstone strains are particularly common among animals and feedstuffs in Sweden and that they are not related to human cases of enteritis in this country. We also conclude that biochemical fingerprinting with the PhP system is a reliable and highly discriminatory method for detecting epidemic strains of Salmonella Livingstone.     

In vitro analyses for predicting standardised ileal digestibility of protein and amino acids in actual batches of feedstuffs and diets for pigs

In vitro digestibility analyses of feedstuffs and diets are integrated in the new Danish feed evaluation system for pigs. This system is based on potential physiological energy and standardised digestible amino acids. For characterisation of the energy value of actual batches of feedstuffs and complete diets for pigs, two different in vitro methods have been developed and proved to analyse precisely the digestibility of organic matter at faecal, as well as at ileal, level in the pigs. For characterisation of the protein value in the diet, table values for standardised digestibility of amino acids from the individual feedstuffs are used for calculation of their contribution to the amino acid recommendations for the specific pig category. The results in the present paper indicate that in vitro analyses for digestibility of crude protein in feedstuffs are a reliable tool for calculation of standardised ileal digestibility of the individual amino acids. Thus, the results may question the need for future experiments with surgically modified pigs for analysing ileal digestibility of amino acids in protein sources. Alternatively, in vitro digestibility analyses appear to have a general potential for a precise evaluation of amino acid digestibility in actual batches of feedstuffs and pig diets.     

对家禽饲料代谢能值评定方法中若干误区的探讨

迄今国际上对禽类饲料代谢能值的表述有诸多方式。在其立论依据、试验设计及测试手段等方法学方面存在着许多悬而未决的问题。本文通过饲料间组合效应,试验设计中的养分有效性分配原则,对经典的套算法在推理中的随意性以及在建立数学模型时必要的校正因子的扬弃等问题进行了探讨。限于篇幅,对家禽饲料代谢能评定方法的技术路线问题拟做另文探讨。     

Effects of physicochemical and structural properties of single and double feedstuffs derived from different botanic sources on in vitro starch digestion and glucose release kinetics

Starch is the largest constituent in animal diets. The aims of this study were as follows: (a) to assess the variability of basic physicochemical properties and in vitro starch digestion of starchy feedstuffs and investigate relationship between physicochemical properties and starch digestion of the feedstuffs, and (b) to explore the effects of different sources of starchy feedstuffs on starch digestion and glucose release. In this study, we determined the inherent molecular structure and granular structure of starch and chemical compositions of seven starchy feedstuffs, as well as starch digestion in single feedstuff and different feedstuffs combined with corn. Scanning electron microscope (SEM) results revealed significant difference between granule shape and size of starch of different feedstuffs. Fourier transforms infrared (FTIR) spectra for barley and wheat had lower (p < 0.05) absorbance band at areas A_860 and A_928 than other feedstuffs, yet rice starch had the lowest value for ratio (R) (1047/1022). Moreover, digestion rate ranged from 0.0157/min for resistant starch (sorghum) to 0.029/min for rapidly starch (broken rice). The principle component analysis (PCA) showed that predicted glycaemic index (pGI) was positively related to A_1022, glucose and rapidly (RDS) content and negatively related to A_995, A_1047, R (1047/1022), resistant starch (RS) and amylose content. Most of the feedstufss with corn combination had no effect on rate of starch digestion. In addition, different starchy feeds and corn combination changed the rate of starch digestion, when barley, however, sorghum combined with corn seemed to affect rate of starch digestion. To sum up, different sources differed in basic physicochemical and structural properties, which would influence the digestion rate of starch and the release of glucose. Combination of different feedstuffs particular sorghum with corn has interactive effect on starch digestion and the release of glucose.     

Comparison of energy deposition and utilization of feedstuffs and rations between growing and adult pigs.

The effect of energy deposition and the utilization of feedstuffs and rations were compared between growing and adult pigs. The good agreement in the data leads to the conclusion, that the energy deposition effect of feedstuffs and rations in growing pigs can be estimated with an equation based on measurements in adult pigs. Exceptions are feedstuffs which are digested bacterially to a relatively high part in the large intestine, as e.g. sugar beet pulp, raw potatoes or similar feed.     

Creatine and creatinine contents in different diet types for dogs – effects of source and processing

The concentrations of creatine and its degradation product creatinine were determined in a variety of unprocessed as well as processed feedstuffs suitable for dogs. Unprocessed feedstuffs were categorised as single feedstuffs, bone and raw food diets (BARF), and small vertebrates, for example prey animals. Processed feedstuffs were categorised as meat/meat and bone meals, complete wet diets and complete dry diets. The feedstuffs were chosen to cover a broad range of each of the three defined processed and unprocessed feed categories available on the market without further subclustering. The creatine content of the samples was compared on a dry matter, protein and energy basis. The relation of creatine to crude protein permitted a rating of the meat quality in terms of muscle tissue. Results: We found no difference in creatine concentrations between the three categories of unprocessed feedstuffs (raw single feedstuffs, prey and BARF diets), neither on a dry matter basis nor when expressed relative to crude protein and metabolisable energy respectively. Significantly lower levels were determined in meat/meat and bone meal and commercial dry diets (e.g. 303 mg creatine/MJ ME in unprocessed vs. 6 mg/MJ ME in processed feedstuffs; p < 0.001). We conclude that in relation to ME, the exclusive use of conventionally processed diets for dogs, especially dry diets, leads to considerably lower intake of creatine which is a natural compound of the diet of this carnivorous and omnivorous species.     

Mycotoxins and reproduction in domestic livestock.

Molds are parasitic plants that are ubiquitous in livestock feedstuffs. Even though molds themselves reduce the quality of grains, their synthesis of chemical substances termed mycotoxins causes the greatest monetary loss to the animal industry. Five major mycotoxins that impair growth and reproductive efficiency in North America are aflatoxins, zearalenone, deoxynivalenol, ochratoxin, and ergot. Aflatoxins are produced by Aspergillus flavus and Aspergillus parasiticus. Consumption of grains containing aflatoxins by swine affects reproduction indirectly by reducing feed intake and growth. In swine, aflatoxins impair liver and kidney function, delay blood clotting, increase susceptibility to bruising, and interfere with cellular humoral immune systems. Ruminants are comparatively resistant to aflatoxicosis, but presence of aflatoxins in milk of dairy cows is closely monitored for human safety. Depending on environmental conditions, Fusarium roseum can produce either zearalenone or deoxynivalenol. Days 7 to 10 postmating seem to be a critical period of gestation for zearalenone to exert its detrimental actions on early embryonic development. Presence of deoxynivalenol in swine feedstuffs decreases feed intake, causes feed refusal, and induces occasional vomiting. Several species of Penicillium and Aspergillus produce ochratoxin, a mycotoxin that causes necrosis of kidney tissue. Ergot alkaloids produced by Claviceps purpurea on wheat can cause reproductive problems and are associated with lactational failure in swine. Various methods have been developed to remove mycotoxins from infected feedstuffs. Chemical analyses in laboratories as well as diagnostic kits suitable for use at the elevator or farm can be used successfully to identify which mycotoxins are present in suspect feedstuffs.     

肉鸭常用饲料原料磷真利用率及真可利用磷预测模型的研究

本试验旨在测定代表性肉鸭饲料原料的总磷和植酸磷含量及其磷真利用率,并建立各原料真可利用磷的预测模型,丰富肉鸭饲料原料数据库,为肉鸭饲粮配方的精确配制提供科学依据.试验收集全国各地常用肉鸭饲料原料,以不同来源饲料原料的化学成分特点及变异规律为依据选出30种代表性样品,采用化学分析法测定样品的总磷和植酸磷含量,以成年樱桃谷...     

Determination of nitrates in feed and blood samples

Nitrate and nitrite compounds in feedstuffs were readily and immediately absorbed from the digestive tract right after intake. Nitrate, therefore, is reflected in the blood, depending on intake quantity. Nitrate concentrations recorded from the blood are superior to values established from feedstuffs in substantiating conclusions as to intake quantity. A diagnosis of nitrate intoxication, based on feedstuff testing, should be confirmed by blood testing. Two methods are proposed for quantity determination of nitrate levels in feedstuffs and blood. The presence of hypomagnesaemia should be ruled out in any differential diagnosis undertaken for suspicion of nitrate intoxication.     

Dioxins: risk management by agriculture and feed industry--options and limits

Dioxins represent a group of undesired substances that may contaminate feedstuffs. Due to their persistency in the environment it can be expected that feed contamination by dioxins will occur in the future, too. Therefore efforts in agriculture and in the feed industry have to be focussed on measures that minimize the dioxin contamination of feedstuffs, especially under the aspects of food safety. Several dioxin scandals in the past have contributed to a higher awareness in feed production as well as on the side of food consumers and administration resulting in changes of feed legislation (implementation of maximum levels of dioxins in feed and food). Some of the dioxin scandals enlarged the knowledge concerning the potential ways dioxins entering the food chain (for example dioxin contamination during the drying process of grass meal, recycling of contaminated oils, use of contaminated kaolinit a.s.o.). In difference to those accidents in feed producing agriculture there is a main influence of potential soil contamination on the dioxin contents in feedstuffs (like roughage). Producing roughage (green fodder, silage, hay) on areas with grass land by grazing animals can result in corresponding consumption of soil that contaminates the green fodder. Intending a lowest feed contamination by dioxins implies that the soil contamination is known. Depending on the rate of soil contamination farmers should decide on the kind of feed production and on the techniques of harvesting the fodder. For example it is possible to produce maize (whole plant in high cut technique) without higher dioxin contents in maize silage, on the other hand it can not be recommended to use contaminated fields for growing beets or by grazing ruminants, pigs or poultry (outdoor systems). In general during the harvesting process technical measures have to be chosen that reduce/minimize the soil contamination because the dioxin concentration in the soil of exposed areas is much more higher than the dioxin concentration within the feedstuffs. The high costs of dioxin analyses limit an implementation of a monitoring program including samples of soil and feedstuffs of each feed producing unit or individual farms. Therefore it is necessary to focus the monitoring efforts on areas and samples that let expect a higher risk of dioxin contamination. New screening tests should be developed and implemented that allow a higher frequency and density of control measures concerning dioxin. In the case of suspicious findings only those samples could be analysed by the classic chemical procedure (time consuming, high costs). Especially in cases of food contamination (for example detected in monitoring programs of the food industry) it is necessary to find out the way and cause, not neglecting the potential role of the contaminated soil. Last but not least it is recommended to inform the public continuously about levels of dioxins that are actually found in food as well as in feed (and soils), especially on behalf of the consumers confidence in food and feed control and its related administration. Continuous information will increase the consumers understanding that there is (and will be for further years) a background contamination of feed and food in general (that decreased markedly in the last decades), and that cases of detected higher dioxin levels are exceptional findings that result immediately in efforts of the food and feed industry to obstruct the way that enabled an entering to the food chain.     

Nutrient Content of Organically Grown Feedstuffs

Many smaller farms in the United States are switching to organic crop production to remain competitive with industrial agriculture. In doing so, they are cultivating crops not traditionally grown in the area. Organically grown corn, wheat, barley, oats, soybeans, field peas, buckwheat, and flaxseed samples were obtained from producers throughout the Midwest. The nutrient content of the organically grown feedstuffs was compared with published values for industrially grown counterparts. The nutrient content of a given feedstuff has been shown to vary because of differences in climate, soil conditions, maturity, cultivar, management, and processing factors. As an emerging industry, organic crop production practices vary considerably from farm to farm. As a result, there is considerable variation in the nutrient content of organically grown feedstuffs, as noted with the samples analyzed. This variation will affect the formulation of organic livestock feeds and demonstrates the need to develop a database of the nutrient content of organically grown feedstuffs.     

鸡饲料氨基酸利用率测定存在的问题及参数的选择

本文从生物学效价评定方法学的角度对鸡饲料氨基酸利用率测定手段中存在的问题进行了探讨,并就８０年代以来国内外发表的具有可比性的常用鸡饲料的必需氨基酸的真利用率测值进行了归纳整理,可供读者在引用借鉴饲料氨基酸利用率文献资料时参考。     

抽样调查北京地区猪场饲料及饲料原料玉米赤霉烯酮污染状况

本研究采用免疫亲和柱高效液相色谱法测定了北京地区猪场饲料原料及全价饲料中玉米赤霉烯酮（ＺＥＮ）的含量,以了解北京地区饲料中 ＺＥＮ的污染情况。试验抽样采集北京市昌平区、大兴区、延庆区、平谷区、顺义区 ５个区县 １５个猪场 １３１份饲料样［５５份玉米、豆粕、麸皮、干酒糟及其可溶物（ＤＤＧＳ）原料,７６份猪全价饲料］进行 ＺＥＮ含量的测定。结果表明：玉米、豆粕、麸皮、ＤＤＧＳ和全价饲料中 ＺＥＮ的检出率分别为 １００．００％、５４．４５％、１００．００％、１００．００％和 ５８．８８％,超标率分别为 ０．００％、０．００％、０．００％、４１．１８％和 ０．００％,平均含量分别为 １０９．０８、９．１９、１４．９２、８８２．６８和 ５８．８８μｇ／ｋｇ。结果提示,不同饲料原料中 ＺＥＮ含量存在差异,ＤＤＧＳ中 ＺＥＮ平均含量超标,猪全价饲料及玉米、豆粕等饲料原料中 ＺＥＮ平均含量均未超标。     

Fine particles and dust in animal feeds--quantitative and qualitative (fungi, bacteria and LPS) aspects

Unground feedstuffs like cereals and roughage which are conspicuous by high proportions of finer particles and dust have to be estimated as risky environmental factors due to the accumulation of microorganisms (moulds, bacteria and lipopolysaccharides) and mites in the fines frequently. The dusty fraction in feed samples should be separated by sensorial inspection of feedstuffs (for example by sieves) and has to be looked at (using pocket lens) critically to find out lacks in the hygienic quality of feedstuffs. Dusty qualities of roughage contain high counts of moulds frequently, therefore a mycological investigation is to be recommended for these samples. The feedstuffs may influence the quantity and quality of air dust within the stable as the starch content (similar to the fed diet) indicates. Likewise corresponding LPS contents were measured in feeds and airborne dust of pig stables. Due to the high counts of microorganisms in the dusty fraction of cereals an intensive cleaning procedure for cereals has to be recommended for minimizing the load of germs; a reduced risk for deterioration can be expected. The residues of cleaning processes (combined mechanic/pneumatic procedures) of cereals should not be reutilized in the production of compound feeds by feed manufacturers, the nutritive value is relatively low anyway due to the high ash- and fiber-contents. Potential risks of dusty feedstuffs to animals' health and the influences of mites, moulds and lipopolysaccharides on the development of gastrointestinal and respiratoric disturbances are discussed. Experimental investigations are needed to elucidate the role of inhaled dust--and its content of lipopolysaccharides especially--in the development of respiratory diseases in veterinary medicine.     

Feeding and performance of pigs in smallholder production systems in Northern Lao PDR

A survey was carried out in the North of Lao PDR to study feeding systems and the performance of pigs in smallholder systems. A total of 341 farmers from five provinces were interviewed. To feed their pigs, farmers mainly rely on feedstuffs produced on the farm and collected from areas near the village. The feedstuffs used included by-products such as rice bran and distiller’s waste, planted feeds, mainly maize and cassava, and various green plant materials. The feedstuffs used are usually high in energy and low in protein content, and the only readily available protein source is green plant material. This results in nutritionally imbalanced diets and as a result poor pig performance. The average growth rate of pigs in these systems was found to be only approximately 100 g/day. The reproductive performance of sows was found to be relatively low, as is the case of local breeds in the region, with an average litter size at birth of 6.8 piglets. The mortality of piglets was as high as 50% and was a main concern of farmers. In order to improve the productivity of pigs in smallholder systems, there is a need to find alternative feed resources to improve the nutritional feed quality, and to develop management systems which are suited to the needs and practices of smallholders.     

Establishment of Tabulated Values for Standardized Ileal Digestibility of Crude Protein and Essential Amino Acids in Common Feedstuffs for Pigs

Literature data on apparent ileal digestibility of crude protein (CP) and amino acids in pigs from 79 references (203 observations) including 13 different common feedstuffs, and other data on basal endogenous ileal loss of CP and amino acids from 32 references (36 observations) were analysed statistically. The analyses revealed that the cannulation method as well as the method for determining endogenous ileal losses of CP and amino acids affected the results. After correction for these effects a new set of tabulated values for apparent and standardized ileal digestibility of crude protein and essential amino acids was generated. The results were in most cases in good agreement with three recently published tables for standardized ileal digestibility of amino acids in feedstuffs. Therefore, it was concluded that the data obtained in the present work, together with those given in the recently published tables, would be a suitable basis for a general table for standardized ileal digestibility of CP and amino acids in common feedstuffs for pigs.