Dairy Cattle Feed Research Articles

Increasing nutrient use efficiency through improved feeding and manure management in urban and peri-urban livestock units of a West African city: A scenario analysis

In many African cities urban and peri-urban agriculture (UPA) plays a major role in creating jobs and contributing to food security. However, many small-scale UPA systems are characterised by excessive nutrient inputs to the livestock unit and poor handling of manure. To assess the impact of improved feeding and manure management on nutrient use efficiency within the cattle unit, simulation modelling was used to compare three typical UPA farm types in Niamey, Niger, that comprised: animal husbandry alone (AH), animal husbandry plus gardening (AH+G), and animal husbandry plus gardening plus millet cultivation (AH+G+M). Improved feeding increased annual body weight gain and milk offtake from cattle and reduced the amount of nitrogen (N) excreted in urine, thereby lowering the risk of N emissions. With improved manure management, dry matter (DM) and nutrients recycled per animal and year, and potentially available for cropping, ranged from 321–690kgDM, 8–22kgN, 1.2–2.5kg phosphorus (P), and 3.0–5.6kg potassium (K) in AH as well as AH+G+M farms compared to 221–479kgDM, 5.0–14.0kgN, 0.7–1.6kgP, and 2.0–4.0kgK in AH+G farms. These amounts were up to 2.2-, 2.5-, 1.9- and 1-fold higher than the quantities of DM, N, P and K recycled under current practices. Feeding dairy cattle according to their requirements will enhance milk and meat production; if coupled with regular manure collection and low-cost covering of manure heaps, substantial amounts of nutrients are recycled to cropland and vegetable gardens and environmental pollution is reduced.

Interactions between methane mitigation additives and basal substrates on in vitro methane and VFA production

Seven feed additives (i.e., quillaja saponins, fumaric acid, garlic oil, fish oil, cinnamaldehyde, monensin, and medium chain fatty acids (MCFA)), were evaluated for their effects on CH4 inhibition in vitro in combination with four substrates: concentrate (CON), grass silage (GS), maize silage (MS) and the mixture of CON+GS+MS (300:350:350 (dry matter, DM), MIX), all feeds regularly used in dairy cattle feeding. Substrates and additives were incubated in a batch incubation system containing buffered rumen fluid for 24h. Cinnamaldehyde had an interaction with substrate for CH4 inhibition, volatile fatty acid (VFA) production and inhibition of CH4 relative to VFA. For fumaric acid, interactions occurred for CH4 relative to VFA. Fish oil, quillaja saponins and MCFA had additive×substrate interactions for inhibition of CH4 and VFA production, but they had no interactions for CH4 relative to VFA. Garlic oil had no interaction with substrates for CH4 production and CH4 relative to VFA, but had interactions for VFA production. Monensin had substrate×additive interactions for CH4 and VFA production and CH4 relative to VFA. Monensin and quillaja saponins were more effective at inhibiting CH4 production when combined with GS and MS than with CON. Fish oil had higher inhibition when combined with CON and GS than with MS. The MCFA had higher inhibitions when combined with MS and were lowest with CON, the combination with GS was intermediate and differed from both other substrates. Cinnamaldehyde and MCFA decreased, whereas fumaric acid increased the total VFA production. No other additive affected total VFA production. As a general CH4 mitigation strategy, fumaric acid, garlic oil and fish oil were better in combination with CON. Monensin was more effective in combination with GS, and quillaja saponins were more effective when combined with MS. Cinnamaldehyde and MCFA strongly inhibited fermentation which impaired appropriate evaluation of the most promising combination. Despite additive×substrate interactions, CH4 and VFA production in incubations with CON, GS and MS did not differ from the weighted average of incubations with single substrates with or without additives. Hence no synergism between additive and substrate combinations seemed to exist. Results clearly indicate interactions between additives and substrates. However, it is unlikely that this interaction is the origin of often variable results among in vitro studies.

Metabolic characteristics in ruminants of the proteins in newly developed hull-less barley varieties with altered starch traits

Recently, new varieties of hull-less barley have been developed with altered carbohydrate traits. To our knowledge, there is no study on metabolic characteristics in ruminants of the proteins in the newly developed hull-less barley varieties. The objectives of this study were to: compare metabolic characteristics of the proteins of zero-amylose waxy (CDC Fibar), low-amylose waxy (CDC Rattan), high-amylose (HB08302), and normal starch (CDC McGwire) hull-less barley. In situ animal trials were carried out to generate the original rumen fermentation data for modeling nutrient supply to dairy cattle by using two dairy nutrition models – Dutch DVE/OEB system and NRC 2001. The major comparisons were made in terms of i) truly absorbed protein in the small intestine (DVE or MP, and ii) degraded protein balance (DPB). The study revealed that zero-amylose waxy hull-less barley was superior (P<0.05) in both DVE (123 vs. 117, 114, 103gkg−1 DM) and MP (112 vs. 93, 96, and 87gkg−1 DM) when hull-less barley was evaluated as a single feed for dairy cattle. All of four hull-less barley varieties had negative DPB (DPBOEB; −37.4, −17.1, −30.2, and −28.2gkg−1 DM for normal starch, zero-amylose waxy, waxy, and high-amylose cultivar, respectively), indicating the potential N shortage. In conclusion, the alteration of starch structure in granule provided a relatively balanced energy and protein for microbial synthesis in the rumen. The DVE and DPB predicted by using the DVE/OEB system can be explained (r2>0.76) by the equivalent parameters, predicted by using the NRC 2001 model. The alteration of starch structure in granule affects metabolic characteristics of the proteins of hull-less barley in ruminants.

Feed inventory and smallholder farmers’ perceived causes of feed shortage for dairy cattle in Gisagara District, Rwanda

A survey was conducted to indentify dairy cattle feed resources and smallholder farmers' perceived causes of feed shortage in the central and southern plateaus of Gisagara District, Rwanda. Data were obtained by interviewing 120 smallholder milk producers using structured questionnaires and through direct observations made during transect walks. In all the surveyed areas, rangelands (mean rank = 1.12), crop residues (1.21), improved grasses (2.34), browse (3.23) and herbaceous (4.84) legumes were ranked as the main feed resources. Pennisetum purpureum (95% of the respondents), Leucaena diversifolia (60%) and Calliandra calothyrsus (40%) were the most cultivated fodders in all the plateaus. The dominant crop residue was Zea mays stover (65% of the farmers) in the surveyed areas. In both plateaus, land scarcity was ranked (mean rank = 1.45) as the most important cause of feed shortage followed by inadequacy of forage planting material (2.72) and lack of knowledge on forage production and utilisation (3.02). To ensure sustainable viability of smallholder dairying in densely populated highlands, screening and evaluation of high-yielding and easily propagated pastures, incorporation of forages into cropping systems, value addition of low quality roughages and training farmers on forage production and utilisation should be prioritized.

Bir Yem Fabrikası Tarafından Türkiye’de Üretilen Yem ve Yem Hammaddelerinde Çeşitli Mikotoksinlerin Miktarlarının Belirlenmesi

Summary The aim of this study was to determine aflatoxin B 1 (AFB1), T-2 toxin, fumonisin, deoxynivalenol (DON) and zearalenone (ZEN) levels in various feedstuffs (local and imported feed materials) and feed produced in a feed manufacturer. In addition, aflatoxin M 1 (AFM1) levels were determined in raw cow milks (n = 24) collected from 10 certain dairy cattle farms. The samples consisted of dairy cattle (n = 26), fattening (n = 4), and calf starter (n = 4) feed, as well as feedstuffs (n = 40). All of the samples were analysed by ELISA. In the analysed samples, the incidence of AFB1, AFM1 and T-2 toxins, fumonisin, DON and ZEN were 100%, 80%, 75% and 33%, respectively. The results of this study in feedstuffs and feed revealed that the mycotoxin levels were lower than the mycotoxin limits of the European Union (EU) and Turkey. In previous studies, high concentrations of mycotoxins, especially AFB1 and AFM1, were identified in feedstuffs, feeds and milk in Turkey. In contrast, the mycotoxin levels in the current study were lower than that from the previous studies. The mycotoxin concentrations in imported feed materials (except fumonisin) were lower than those in feed materials obtained from Turkey. The results of this study indicate that the mean mycotoxin levels in feedstuff and feeds do not cause toxic effects in animals, and humans for AFM1.

Phylogeny and pathogenicity ofFusarium oxysporumisolates from cottonseed imported from Australia into California for dairy cattle feed

A unique biotype of the Fusarium wilt pathogen, Fusarium oxysporum Schlecht. f.sp. vasinfectum (Atk) Sny. & Hans., found in Australia in 1993 is favored by neutral or alkaline heavy soils and does not require plant parasitic nematodes to cause disease. This makes it a threat to 4-6 million acres of USA Upland cotton ( Gossypium hirsutum L.) that is grown on heavy alkaline soil and currently is not affected by Fusarium wilt. In 2001-2002, several shiploads of live cottonseed were imported into California for dairy cattle feed. Thirteen F. oxysporum f.sp. vasinfectum isolates and four isolates of a Fusarium spp. that resembled F. oxysporum were isolated from the imported cottonseed. The isolates, designated by an AuSeed prefix, formed four vegetative compatibility groups (VCG) all of which were incompatible with tester isolates for 18 VCGs found in the USA. Isolate AuSeed14 was vegetatively compatible with the four reference isolates of Australian biotype VCG01111. Phylogenetic analyses based on EF-1α, PHO, BT, Mat1-1, and Mat1-2 gene sequences separated the 17 seed isolates into three lineages (race A, race 3, and Fusarium spp.) with AuSeed14 clustering into race 3 lineage or race A lineage depending on the genes analyzed. Indel analysis of the EF-1α gene sequences revealed a close evolutionary relationship among AuSeed14, Australian biotype reference isolates, and the four Fusarium spp. isolates. The Australian seed isolates and the four Australian biotype reference isolates caused disease with root-dip inoculation, but not with stem-puncture inoculation. Thus, they were a vascular incompetent pathotype. In contrast, USA race A lineage isolates readily colonized vascular tissue and formed a vascular competent pathotype when introduced directly into xylem vessels. The AuSeed14 isolate was as pathogenic as the Australian biotype, and it or related isolates could cause a severe Fusarium wilt problem in USA cotton fields if they become established.

Effect of distillers grains moisture and inclusion level in livestock diets on greenhouse gas emissions in the corn-ethanol-livestock life cycle

<h2>ABSTRACT</h2> A model was previously developed (Biofuel Energy Systems Simulator; https://www.bess.unl.edu) to predict greenhouse gas (GHG) emissions and net energy yield when ethanol is produced from corn. The model also predicts feedlot cattle, dairy cattle, and swine performance and feed replacement value of ethanol coproducts. Updated equations that predict performance of feedlot cattle fed 0 to 40% of dietary DM as corn wet (WDGS), modified (MDGS), or dry (DDGS) distillers grains plus solubles replacing dry-rolled and high-moisture corn were developed and incorporated into the model. Equations were derived from pen-level performance for 20 finishing studies evaluating WDGS, 4 evaluating MDGS, and 4 evaluating DDGS conducted at the University of Nebraska. Feeding value of WDGS was 145 to 131% of corn replaced when included at 20 to 40% of diet DM due to a quadratic (P < 0.01) increase in G:F. The feeding value of MDGS was 124 to 117% with a quadratic (P < 0.01) increase in G:F and 112 to 110% for DDGS with a linear (P < 0.01) increase in G:F. Midwest corn-ethanol-livestock life cycle GHG reduction relative to gasoline (97.7 g CO₂equivalent/MJ of ethanol) was 61 to 57% when WDGS was fed to feedlot cattle for 20 to 40% diet inclusion. Feeding MDGS and DDGS to feedlot cattle reduced GHG emissions from the corn-ethanol-cattle system by 53 to 50% and 46 to 41%, respectively. Feeding WDGS to feed-lot cattle was the optimum feed use of distillers grains plus solubles based on feeding performance and GHG reduction.

Produk Fermentasi Rumen dan Produksi Protein Mikroba Sapi Lokal yang Diberi Pakan Jerami Amoniasi dan Beberapa Bahan Pakan Sumber Energi

Products of rumen fermentation and protein microbial of dairy cattle feed with rice bran ammonization and some feedstuffs as an energy sourcesABSTRACT. This study aims to examine the energy sources of feed ingredients that can increase the production of Volatile Fatty Acids (VFA), N-NH3, microbial protein synthesis, total gas production and metabolic energy. The material used is as a source of rumen fluid inoculum from Frisian Holstein cows (FH) females, amoniasi rice straw, salt, mineral mix brand "Ultra Minerals' production Eka Farma Semarang, onggok wet and dry, corn, and rice bran. Observed variable is the concentration of (VFA), N-NH3, rumen microbial protein synthesis, and total gas production. Based on the analysis of diversity seen any significant effect (P0.05) on total VFA concentration, N-NH3 and total gas but had no effect (P0.05) on microbial protein synthesis. Conclusion of research is the provision of energy sources with rice bran treatment, onggok wet and dry corn flour can be used as fermentable carbohydrates on feed hay amoniasi in vitro.

Assessing a decade of phosphorus management in the Lake Mendota, Wisconsin watershed and scenarios for enhanced phosphorus management

A phosphorus (P) budget was estimated for the watershed of Lake Mendota, Wisconsin, to assess the effects of nutrient management on P accumulation in the watershed soils. We estimated how nutrient management programs and legislation have affected the budget by comparing the budget for 2007 to a budget calculated for 1995, prior to implementation of the programs. Since 1995, inputs decreased from 1,310,000 to 853,000 kg P/yr (35% reduction) and accumulation decreased from 575,000 to 279,000 kg P/yr (51% reduction). Changes in P input and accumulation were attributed primarily to enhanced agricultural nutrient management, reduction in dairy cattle feed supplements and an urban P fertilizer ban. Four scenarios were investigated to determine potential impacts of additional nutrient management tactics on the watershed P budget and P loading to Lake Mendota. Elimination of chemical P fertilizer input has the greatest potential to reduce watershed P accumulation and establishment of riparian buffers has the greatest potential to prevent P loading to Lake Mendota.

Nuclear Magnetic Resonance (NMR) Studies on the Biosynthesis of Fusaric Acid from Fusarium oxysporum f. sp. vasinfectum

Fusarium oxysporum is a fungal pathogen that attacks many important plants. Uniquely pathogenic strains of F. oxysporum f. sp. vasinfectum were inadvertently imported into the United States on live cottonseed for dairy cattle feed. These strains produce exceptionally high concentrations of the phytotoxin fusaric acid. Thus, fusaric acid may be a critical component in the pathogenicity of these biotypes. This study investigated the biosynthesis of fusaric acid using (13)C-labeled substrates including [1,2-(13)C(2)]acetate as well as (13)C- and (15)N-labeled aspartate and [(15)N]glutamine. The incorporation of labeled substrates is consistent with the biosynthesis of fusaric acid from three acetate units at C5-C6, C7-C8, and C9-C10, with the remaining carbons being derived from aspartate via oxaloacetate and the TCA cycle; the oxaloacetate originates in part by transamination of aspartate, but most of the oxaloacetate is derived by deamination of aspartate to fumarate by aspartase. The nitrogen from glutamine is more readily incorporated into fusaric acid than that from aspartate.

Presence and Determination of Manure-borne Estrogens from Dairy and Beef Cattle Feeding Operations in Northeast China

Four estrogens in cattle feces collected from 24 dairy and beef feeding operations located in the northeast of China were investigated. The average concentration of 17α-estradiol, 17β-estradiol and estrone in dairy feces was 194.6, 104.4, and 262 μg/kg, respectively. While as to beef waste the mean content of 17α-estradiol, 17β-estradiol and estrone was 104.5, 67.7 and 216.4 μg/kg, respectively. Estriol was below the detection limit in all samples. The 17β-estradiol equivalents of all samples ranged from 45.8 to 926.1 μg/kg and dairy together with beef probably generated 16 times more estrogens than the human population in the study area.

Correlation between median and mean irregular particle sizes and degradation kinetics in barley genotypes

Barleys, a major source of feed, are all coarsely dry-rolled before feeding beef and dairy cattle in North America. The shapes of coarsely dry-rolled barley particles are not round but very irregular. The model for geometric mean is not suitable for determining irregular barley particle size. In a previous study, we tested four different published models to determine the mean and median particle sizes of coarsely dry-rolled barley with irregular particle size shapes and found that the Pond's model with 0 mm=100% was the best model to compute mean and median particle sizes of the coarsely dry-rolled barley samples expressed as per cent cumulative weight oversize. However, we still did not know which parameter, median or mean particle size, was the best indicator to predict rumen nutrient degradation and availability. This information is badly needed. The objective of this study was to study the relationship between the mean and median irregular particle sizes and nutrient availability of various barley varieties which were coarsely dry-rolled. The results revealed a stronger correlation between the median irregular particle size (not mean particle size) and the rate (K(d) ) and extent (ED) of rumen degradation of dry matter (K(d) : R= -0.78, p= 0.065; EDDM: R= -0.89, p= 0.016), starch (K(d) : R= -0.96, p= 0.003; EDST: R= -0.95, p= 0.003) and crude protein (K(d) : R= -0.59, p= 0.215; EDCP: R= -0.89, p= 0.019). In conclusion, it is the median but not mean particle size that has stronger correlation with rumen degradation kinetics. The 79.9%, 78.3% and 91.0% of variation of effective degradability of dry matter, crude protein and starch, respectively, could be explained by the median irregular particle size.

Results of one-year investigations of the contamination of dairy cattle feed and raw milk with moulds and mycotoxins

The contamination of 98 dairy cattle feed samples with moulds and mycotoxins (AB1, OTA, ZEA) was investigated. The contamination of 80 raw milk samples with aflatoxin M1 was also tested. Determination of total viable counts per 1g of feed was performed using Koch's standard method. The content of AB1, OTA and ZEA in feed, as well as aflatoxin M1 in raw milk samples, was determined by VICAM fluorimetric method. Results showed that 91% of all tested samples was contaminated with moulds, and total viable mould count per gram ranged from 10 (corn silage - spring) to 4.9 x 106 per gram (dried alfalfa - winter). The isolated moulds belong to 20 genera and 72 species. Results of mycotoxicological investigations showed that 42 samples of total 98 tested, were contaminated with mycotoxins. The most frequent was OTA (24 samples, 20.00 - 210.00 ?g/kg) followed with ZEA (12 samples, 250.00 - 980.00 ?g/kg) and AB1 (3 samples, traces - 18.50 ?g/kg). Aflatoxin M1 in raw milk samples wasn?t found.

Involvement of small-scale dairy farms in an industrial supply chain: when production standards meet farm diversity

In certain contexts, dairy firms are supplied by small-scale family farms. Firms provide a set of technical and economic recommendations meant to help farmers meet their requirements in terms of the quantity and quality of milk collected. This study analyzes how such recommendations may be adopted by studying six farms in Brazil. All farms are beneficiaries of the country's agrarian reforms, but they differ in terms of how they developed their activities, their resources and their milk collection objectives. First, we built a technical and economic benchmark farm based on recommendations from a dairy firm and farmer advisory institutions. Our analysis of the farms’ practices and technical and economic results show that none of the farms in the sample apply all of the benchmark recommendations; however, all farms specialized in dairy production observe the main underlying principles with regard to feeding systems and breeding. The decisive factors in whether the benchmark is adopted and successfully implemented are (i) access to the supply chain when a farmer establishes his activity, (ii) a grasp of reproduction and forage production techniques and (iii) an understanding of dairy cattle feed dietary rationing principles. The technical problems observed in some cases impact the farms’ dairy performance and cash position; this can lead to a process of disinvestment. This dynamic of farms facing production standards suggests that the diversity of specialized livestock farmers should be taken into account more effectively through advisory approaches that combine basic zootechnical training with assistance in planning farm activities over the short and medium term.

Improving the efficiency of energy utilisation in cattle

The efficiency of energy utilisation in cattle is a determinant of the profitability of milk and beef production, as well as their environmental impact. At an animal level, meat and milk production by ruminants is less efficient than pig and poultry production, in part due to lower digestibility of forages compared with grains. However, when compared on the basis of human-edible inputs, the ruminant has a clear efficiency advantage. There has been recent interest in feed conversion efficiency (FCE) in dairy cattle and residual feed intake, an indicator of FCE, in beef cattle. Variation between animals in FCE may have genetic components, allowing selection for animals with greater efficiency and reduced environmental impact. A major source of variation in FCE is feed digestibility, and thus approaches that improve digestibility should improve FCE if rumen function is not disrupted. Methane represents a substantial loss of digestible energy from rations. Major determinants of methane emission are the amount of feed consumed and the proportions of forage and concentrates fed. In addition, feeding fat has long been known to reduce methane emission. A myriad of other supplements and additives are currently being investigated as mitigators of methane emission, but in many cases compounds effective in sheep are ineffective in lactating dairy cows. Ultimately, the adoption of ‘best practice’ in diet formulation and management may be the most effective option for reducing methane. In assessing the efficiency of energy use for milk and meat production by cattle, and their environmental impact, it is imperative that comparisons be made at a systems level, and that the wider social and economic implications of mitigation policy are considered.

Extruded Pea (Pisum Sativum) as Alternative to Soybean Protein for Dairy Cows Feeding in Organic Alpine Farms

The study evaluated the use of extruded pea as an alternative to soybean in the protein feeding of dairy cattle raised in organic Alpine farms. The research was carried out in a commercial organic dairy farm located in the Province of Trento (Northern Italy) and it considered two separate periods of cows’ lactation: early and late lactation. According to the traditional management practice of alpine dairy herds with the seasonal calving of the cows in early winter, the former period was carried out during the cold season when cows were housed indoors, while the latter period started after the transfer of the entire herd to an alpine pasture for the summer grazing. In both periods, 16 cows of Rendena breed were equally assigned to 2 experimental groups. The dietary forage (meadow hay in early lactation or pasture in late lactation) was supplemented to one group of cows with a Control concentrate in which soybean expeller, sunflower expeller and wheat bran were the main protein feeds. Soybean proteins were replaced by extruded peas in the Soy-free concentrate given to the other group of cows. The daily amount of concentrate was adjusted to the individual milk yield on a weekly basis adopting ratios of 0.360 and 0.125 kg of DM per kg of milk in early and late lactation periods, respectively. Cows receiving Soy-free concentrate showed a higher milk yield than the Control cows in both lactation periods (18.7 vs 17.5 kg/d in early lactation and 9.3 vs 8.6 kg/d on pasture, respectively). Milk fat and protein were not affected by the diet at any stage of lactation, while a higher concentration of milk urea was observed in milk samples taken from Soy-free cows in both periods of the study. This result could have been promoted by the higher soluble fraction of extruded pea proteins in comparison to that of soybean expeller. Cows feeding behaviour was monitored only in the early lactation period and despite of the different amount of concentrate consumed by the two groups of cows (7.0 vs 6.6 kg/cow/d for Soyfree and Control, respectively), their total time spent eating and ruminating was not affected by the diet. Based on these findings, extruded peas can be considered a valuable alternative to soybean in the protein feeding of cattle raised for organic milk production in the Alpine region.

Rendimentos agrícola e forrageiro de três cultivares de cana-de-açúcar (Saccharum spp.) em diferentes épocas de corte

Objetivou-se, neste trabalho, avaliar os rendimentos agrícola e forrageiro de três cultivares de cana-de-açúcar em diferentes épocas de corte (maio, julho e setembro), onde há uma maior demanda de forragem na região. O experimento foi instalado no município de Lavras, Minas Gerais. O clima é do tipo mesotérmico e o solo é um Latossolo Vermelho Escuro. O delineamento experimental utilizado foi o de blocos casualizados, em esquema fatorial 3 X 3, com 3 repetições. Os tratamentos foram constituídos por três cultivares de cana-de-açúcar (RB825336; SP80-1816 e RB835054) e por três épocas de corte (maio; julho; setembro). Cada parcela foi constituída por 6 linhas de cana-de-açúcar, espaçadas de 1,25m, com 8m de comprimento, com uma área total de 60m². A área útil de parcela correspondeu às quatro linhas centrais, eliminando-se 1,0m de cada extremidade, com uma área de 30,0m². Foram avaliados os rendimentos de massa verde, massa seca, tonelada de colmos por hectare e sacarose (g/100g caldo). Os resultados mostraram que não houve efeitos de cultivares e das épocas de corte estudadas nos rendimentos dos colmos, massa verde, matéria seca e sacarose da cana-de-açúcar. Os altos rendimentos obtidos para massa verde e matéria seca, no período de seca (maio a setembro), mostram o grande potencial da cana-de-açúcar para uso na alimentação do rebanho leiteiro na região.

Chemical analysis of dairy cattle feed from Brazil

The bovine dairy cattle demand diets of high nutritional value being essential to know chemical composition of feed supplied to cows to achieve high levels of quality, safety and productivity of milk. Different roughages and concentrates from Minas Gerais and Rio Grande do Sul states, Brazil, were analyzed by instrumental neutron activation analysis (INAA) and inductively coupled plasma mass spectrometry (ICP-MS). Concentrate and roughage samples were differentiated by mass fractions of As, Ba, Mg, P, Rb and Sr. Samples of concentrate from both origins were differentiated by mass fractions of As, Cd, Co, Cr, Cs, Ni and Rb.

Gliotoxin natural incidence and toxigenicity of Aspergillus fumigatus isolated from corn silage and ready dairy cattle feed

Corn silage is an important feed source for dairy and beef cattle in central Argentina. The presence of thermophilic species Aspergillus fumigatus is among the major problem in silage, as many strains can produce several mycotoxins that affect the health of dairy cattle. The aims of the present study were to determine total fungal counts and relative density of A. fumigatus in silage samples, and to determine the natural incidence of gliotoxin in silage and ready dairy feed samples. The potential gliotoxin production of A. fumigatus isolated from silage was also recorded. A total of 90 samples were investigated, which were taken immediately after opening of the silo and the end of the ensiling period of about after 5 months. Sampling was performed manually through silos in transects at 3 levels per silo. Thirty samples of ready cattle feed (corn silage, ground corn, barley, cotton seed, brewer grains) were collected and investigated as well. Gliotoxin contamination was determined by HPLC. The ability of A. fumigatus to produce gliotoxin was measured using a TLC method. Results show that in all samples, the total number of yeasts and moulds exceeded 1×104 cfu/g. Aspergillus was the most prevalent genus followed by Fusarium and Penicillium spp. Investigations of the isolated A. fumigatus strains showed that many of these strains produced more than one mycotoxin. All samples showed gliotoxin contamination, but the strains isolated from ready cattle feed had higher gliotoxin levels than those isolated from corn silage. The gliotoxin concentrations found in this study exceeded the levels that are known to induce immunosuppressive and apoptotic effects in vitro. Although at present the oral bioavailability of gliotoxin in cattle is not known, the presented data suggest that its presence in feedstuffs could affect productivity and present a health risk for dairy cows.

Study of Digital Management System of Milking Process on Large-Sized Dairy Farm

This study was to supply the systemic and full milking process data to support the implementation of both dairy herd improvement (DHI) and digital feeding of dairy cattle. This study designed the relational structured database and developed a set of digital management information system on milking process of intensive dairy farm using Visual Basic 6.0, Access databases, and Crystal report combining the milking characteristics of a grown cow, such as quality and sanitation testing indexes of raw milk. The system supplies a series of convenient, intelligent input interfaces of crude datum, and can count, analyze, and graphically show milking datum based on different types and different parities of cows or herds in a specific duration, and can dynamically produce some important derived data, such as days of grown cow, daily average of milk production of grown cow, days of cow milk production, and daily average of milking cow production; and can carry out all-pervasive data mining. With the help of system analysis and software design techniques, it is possible to realize precision farming for a dairy cattle herd based on whole digital management of milking process and realtime prediction on nutrient requirements and ration of dairy cattle, as well as dairy herd improvement.