Fluopyram Suppresses Population Densities of Heterodera glycines in Field and Greenhouse Studies in Michigan.

The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, causes significant damage to soybean production annually. Fluopyram is a fungicide commonly used in soybean seed treatments intended to control soilborne fungal pathogens; however, recent studies have also suggested inhibitory effects on SCN. We examined the effects of a fluopyram seed treatment, ILeVO, on SCN reproduction, sudden death syndrome (SDS) development, and yield in a 3-year field study. Overall, fluopyram had a significant effect on yield (P = 0.046) and end-of-season SCN eggs and second-stage juveniles (Pf, P = 0.033) but no significant effect on SCN reproduction (Rf) or SDS disease index (P > 0.05). Post hoc tests indicated that fluopyram increased yield and suppressed SCN quantities. However, Rf was consistently greater than 1 whether or not the seed was treated with fluopyram, indicating that SCN populations were still increasing in the presence of fluopyram. A follow-up greenhouse study indicated that fluopyram reduced SCN relative to nontreated controls, as observed in the field, but only reduced SCN DNA within roots of a susceptible cultivar. These results indicate that fluopyram can suppress SCN quantities relative to nontreated seed but may not successfully reduce nematode populations without the use of additional management strategies.

Effect of dietary fat supplementation on methane emissions from dairy cows fed wheat or corn.

Diets that contain high proportions of either wheat or supplementary fat have been individually reported to reduce enteric methane production. The objective of this research was to determine the effect of dietary fat supplementation on methane emissions and milk yield from cows fed diets containing either corn or wheat grains. It was hypothesized that cows fed a diet containing wheat would produce less methane and have lower methane yield (methane per kg of dry matter intake; MY) than cows fed a diet containing corn and that methane mitigation from fat supplementation would occur irrespective of the type of grain in the basal diet. The experiment involved 32 Holstein-Friesian dairy cows allocated to 1 of 4 treatment groups (n = 8) and individually fed different diets restricted to approximately 90% of their mean ad libitum intake measured during a covariate period. All animals were offered 11.5 kg of dry matter/d of alfalfa hay, 1.8 kg of dry matter/d of solvent-extracted canola meal, and 1 of 4 dietary supplements. Dietary supplements were 8 kg of dry matter/d of either corn or wheat, or these same treatments with the addition of 0.8 kg of canola oil. In this 5-wk experiment, d 1 to 7 served as the covariate period, d 8 to 14 as the transition period, d 15 to 28 as the adaptation period, and d 29 to 35 as the experimental period. Cows were fed their full treatment diets from d 15 to 35 during which time milk production and feed intake were measured daily. During d 29 to 35, methane production was measured for individual cows daily using the sulfur hexafluoride tracer method. The resulting averages for milk production and feed intake were analyzed by analysis of covariance with factorial grain by fat as treatment structure, animal as the unit within blocks, and the corresponding milk production or feed intake covariate averages as principal covariate. Data on milk fatty acids, ruminal fluid data on pH, ammonia, volatile fatty acids, protozoa, and methane were analyzed by ANOVA using the same treatment and blocking structures excluding the principal covariate. Cows fed a diet containing wheat had greater MY than cows fed a diet containing corn. Irrespective of the type of grain in the diet, increasing the fat concentration from 2 to 6% dry matter reduced MY. It is concluded that the grain component in the basal diet does not affect the mitigating effects of dietary fat supplements on MY.

Influence of feeding supplements of almond hulls and ensiled citrus pulp on the milk production, milk composition, and methane emissions of dairy cows.

Almond hulls and citrus pulp have been fed to dairy cows with variable responses for milk production, but no information exists on their effect on enteric methane emissions. This experiment examined the effects of dietary supplementation with either almond hulls or ensiled citrus pulp on the milk yield, milk composition, and enteric methane emissions of dairy cows. Thirty-two Holstein dairy cows in mid lactation were offered 1 of 3 diets over a 28-d experiment. Twelve cows received a control (CON) diet, 10 cows a diet containing almond hulls (ALH), and 10 cows a diet containing ensiled citrus pulp (CIT). All cows were offered 6.0 kg of dry matter (DM)/d of crushed corn, 2.0 kg of DM/d of cold-pressed canola, and 0.2 kg of DM/d of a mineral mix. In addition, cows fed the CON diet were offered 14.5 kg of DM/d of alfalfa cubes; cows fed the ALH diet were offered 10.5 kg of DM/d of alfalfa cubes and 4.0 kg of DM/d of almond hulls; and cows on the CIT diet were offered 11.5 kg of DM/d of alfalfa cubes and 3.0 kg of DM/d of ensiled citrus pulp. Milk yield was measured daily and milk composition was measured on 4 d of each week. Individual cow methane emissions were measured by a sulfur hexafluoride tracer technique on d 24 to 28 of the experiment. The mean milk yield of cows fed the CON diet (27.4 kg/d) was greater than the mean milk yield of cows fed the ALH diet (24.6 kg/cow per day), whereas the mean milk yield of cows fed the CIT diet (26.2 kg/cow per day) was not different from the mean milk yield from cows fed the other 2 diets. Dietary treatment did not influence the concentrations of milk fat, protein, and lactose or fat yields, but the mean protein yield from cows fed the CON diet (0.87 kg/d) was greater than that from cows fed the ALH diet (0.78 kg/d) but not different to those fed the CIT diet (0.85 kg/d). In general, we found no differences in the proportion of individual fatty acids in milk. The mean pH of ruminal fluid from cows offered the CON diet was not different to the pH in the ruminal fluids of cows offered the ALH or the CIT diets. The mean methane emissions (g/d) and yields (g/kg of DM intake) were not influenced by dietary treatment. These findings indicate that, although almond hulls and ensiled citrus pulp can be used as a low-cost feed supplement, almond hulls did negatively affect milk production and neither inhibited enteric methane emissions.

Adaptation responses in milk fat yield and methane emissions of dairy cows when wheat was included in their diet for 16 weeks.

Short-term studies have shown that feeding dairy cows diets containing a high proportion (>40%) of wheat may result in reduced milk fat concentration and reduced CH4 emissions (g of CH4/cow per d), but no long-term studies have been done on these responses. This study compared the milk production and CH4 responses when 24 dairy cows were fed diets containing high proportions of either wheat or corn over 16 wk. Cows were assigned to 2 groups and offered a diet (CRN) containing 10.0 kg of dry matter/d of crushed corn grain, 1.8 kg of dry matter/d of canola meal, 0.2 kg of dry matter/d of minerals, and 11.0 kg of dry matter/d of chopped alfalfa hay or a similar diet (WHT) in which wheat replaced the corn. Dry matter intake and milk yields of individual cows were measured daily. Methane emissions from individual cows were measured using controlled climate respiration chambers over 2 consecutive days during each of wk 4, 10, and 16. Milk composition was measured on the 2 d when cows were in chambers during wk 4, 10, and 16. Over the 16-wk experimental period, total dry matter intake remained relatively constant and similar for the 2 dietary treatment groups. At wk 4, CH4 emission, CH4 yield (g of CH4/kg of dry matter intake), milk fat yield, and milk fat concentration were substantially less in cows fed the WHT diet compared with the same metrics in cows fed the CRN diet; but these differences were not apparent at wk 10 and 16. The responses over time in these metrics were not similar in all cows. In 4 cows fed the WHT diet, CH4 yield, milk fat concentration, and milk fat yield remained relatively constant from wk 4 to 16, whereas for 5 fed the WHT diet, their CH4 emissions, milk fat yields, and milk fat concentrations almost doubled between wk 4 and 16. In the short term (4 wk), the inclusion of approximately 45% wheat instead of corn in the diet of cows resulted in reductions of 39% in CH4 yield, 35% in milk fat concentration, and 40% in milk fat yield. However, these reductions did not persist to wk 10 or beyond. Our data indicate that cows do not all respond in the same way with some "adaptive" cows showing a marked increase in CH4 yield, milk fat concentration, and milk fat yield after wk 4, whereas in other "nonadaptive" cows, these metrics were persistently inhibited to 16 wk. This research shows that short-term studies on dietary interventions to mitigate enteric CH4 emissions may not always predict the long-term effects of such interventions.

Increasing omega-3 levels in meat from ruminants under pasture-based systems.

This review discusses the importance of red meat from ruminants as a source of omega-3 (n-3) fatty acids (FAs) for human life in the context of the contribution of animals to human welfare. Red meat is a valuable food commodity for human life because it is naturally rich in key nutrients such as protein, trace elements, vitamins and essential FAs. In developed countries and high socio-economic groups from developing countries, red meat intake is greater than that of oily fish, owing to availability, preference and affordability. Omega-3 FA concentration is higher in red meat (beef, lamb and mutton) than in white meat (pork, poultry and turkey), due to the fibre types present in muscle tissues and the specialised digestive systems of ruminants. There is mounting evidence that regular consumption of n-3 FAs is beneficial for growth and development as well as the health and welfare of humans of all ages. The dietary background of ruminants significantly influences the concentration of n-3 FAs in red meat. Meat from forage- or grassfed ruminants has a greater concentration of n-3 FAs than that from their feedlot or grain-fed counterparts and can also offer a favourable n-6:n-3 ratio in the meat. Scientific literature shows that the advantages of consuming n-3 FAs enriched meat (foods) outweigh the disadvantages.

Dans le cadre de l'analyse de la contribution des animaux au bien-être de l'homme, les auteurs examinent l'importance pour l'alimentation humaine des acides gras oméga-3 présents dans la viande rouge provenant de ruminants. La viande rouge est une denrée alimentaire précieuse pour l'organisme humain, étant naturellement riche en plusieurs nutriments majeurs tels que protéines, oligo-éléments, vitamines et acides gras essentiels. Dans les pays développés et dans les classes aisées au plan socio-économique des pays en développement, la consommation de viande rouge dépasse celle de poissons gras pour des raisons de disponibilité, de préférence et de prix. La teneur en acides gras oméga-3 est plus élevée dans les viandes rouges (boeuf, agneau et mouton) que dans les viandes blanches (porc, volaille et dinde) du fait des caractéristiques des fibres des tissus musculaires des ruminants et de leur système digestif spécialisé. Il y a de plus en plus d'indices démontrant qu'une consommation régulière d'acides gras oméga-3 est bénéfique pour la croissance et le développement ainsi que pour la santé et le bien-être de l'être humain à tous les âges de sa vie. Le contexte de l'alimentation des ruminants influence de manière significative la teneur en acides gras oméga-3 de la viande rouge. La viande issue de ruminants nourris de fourrage ou à l'herbe présente une concentration plus élevée d'acides gras oméga-3 que celle de leurs homologues des parcs d'engraissement ou nourris au grain, ainsi qu'un ratio oméga 6/oméga-3 favorable. La littérature scientifique montre que la consommation de viandes (ou autres aliments) riches en acides gras oméga-3 apporte plus de bénéfices que d'inconvénients.

Considerando la cuestión desde el ángulo de la contribución de los animales al bienestar humano, los autores examinan la importancia que reviste para la vida humana la carne roja de rumiante como fuente de ácidos grasos omega-3 (n-3). Por su elevado contenido natural en nutrientes fundamentales como proteínas, oligoelementos, vitaminas y ácidos grasos esenciales, la carne roja es un artículo alimentario de gran valor para la vida humana. En los países desarrollados, al igual que entre las élites socioeconómicas de los países en desarrollo, la ingesta de carne roja es superior a la de pescado azul, por razones de disponibilidad, preferencia y asequibilidad. Por los tipos de fibra presentes en el tejido muscular de los rumiantes y por el carácter especializado de su sistema digestivo, la concentración de ácidos grasos omega-3 es mayor en la carne roja (bovinos y ovinos) que en la carne blanca (cerdo, pollo y pavo). Cada vez hay más datos demostrativos de que el consumo regular de ácidos grasos n-3 es beneficioso para el crecimiento, el desarrollo, la salud y el bienestar de las personas a cualquier edad. El tipo de alimentación de un rumiante influye sensiblemente en la concentración de ácidos grasos n-3 que presentará su carne: la carne de rumiantes que han forrajeado o pastado en campos de hierba tiene mayor concentración de esos ácidos grasos que la de sus homólogos procedentes de establos de engorde o alimentados con grano, además de presentar en ocasiones una proporción más favorable entre n-6 y n-3. Los estudios científicos publicados ponen de relieve que el consumo de carne (u otros alimentos) enriquecida en ácidos grasos n-3 tiene más ventajas que inconvenientes.

Wheat is more potent than corn or barley for dietary mitigation of enteric methane emissions from dairy cows.

Wheat is the most common concentrate fed to dairy cows in Australia, but few studies have examined the effects of wheat feeding on enteric methane emissions, and no studies have compared the relative potencies of wheat, corn, and barley for their effects on enteric methane production. In this 35-d experiment, 32 Holstein dairy cows were offered 1 of 4 diets: a corn diet (CRN) of 10.0 kg of dry matter (DM)/d of single-rolled corn grain, 1.8 kg of DM/d of canola meal, 0.2 kg of DM/d of minerals, and 11.0 kg of DM/d of chopped alfalfa hay; a wheat diet (WHT) similar to the CRN diet but with the corn replaced by single-rolled wheat; a barley diet (SRB) similar to the CRN diet but with the corn replaced by single-rolled barley; and a barley diet (DRB) similar to the CRN diet but with the corn replaced by double-rolled barley. Individual cow feed intakes, milk yields, and milk compositions were measured daily but reported for the last 5 d of the experiment. During the last 5 d of the experiment, individual cow methane emissions were measured using the SF6 tracer technique for all cows, and ruminal fluid pH was continuously measured by intraruminal sensors for 3 cows in each treatment group. The average DM intake of cows offered the CRN, WHT, SRB, and DRB diets was 22.2, 21.1, 22.6, and 22.6 kg/d. The mean energy-corrected milk of cows fed the WHT diet was less than that of cows fed the other diets. This occurred because the milk fat percentage of cows fed the WHT diet was significantly less than that of cows fed the other diets. The mean methane emissions and methane yields of cows fed the WHT diet were also significantly less than those of cows fed the other diets. Indeed, the CRN, SRB, and DRB diets were associated with 49, 73, and 78% greater methane emissions, respectively, compared with the emissions from the WHT diet. Methane yield was found to be most strongly related to the minimum daily ruminal fluid pH. This study showed that although the inclusion of wheat in the diet of dairy cows could be an effective strategy for substantially reducing their methane emissions, it also reduced their milk fat percentage and production of milk fat and energy-corrected milk.

Pathogenicity and Virulence of Soilborne Oomycetes on Phaseolus vulgaris.

Dry bean (Phaseolus vulgaris L.) is a globally important leguminous food crop. Yields can be reduced by high incidence of soilborne oomycetes that cause seedling disease. Breeders have attempted to develop Pythium root rot-resistant bean varieties; however, relationships between dry bean and most soilborne oomycete species remain uncharacterized. Oomycete species (n = 28), including Pythium spp. and Phytopythium spp., were tested in a growth chamber seedling assay at 20°C and an in vitro seed assay at 20°C and 26°C to evaluate their pathogenicity and virulence on 'Red Hawk' dark red kidney bean and 'Zorro' black bean. Root size or disease severity was significantly impacted by 14 oomycete species, though results varied by bean variety, temperature, and assay. Of these 14 pathogenic oomycete species, 11 species exhibited significant differences in DSI due to temperature on at least one bean variety. Pythium aphanidermatum, P. myriotylum, P. ultimum, P. ultimum var. sporangiiferium, and P. ultimum var. ultimum were the most virulent species in both assays, causing seed rot and pre-emergence damping-off of dry bean. Oomycete species were clustered into three groups based on symptom development: seed rot pathogens, root rot pathogens, or nonpathogens. Intraspecific variability in virulence was observed for eight of the 14 pathogenic oomycete species. Improved understanding of Pythium and Phytopythium interactions with dry bean may enable breeders and pathologists to more effectively evaluate strategies for oomycete seedling disease management.

Milk production responses to different strategies for feeding supplements to grazing dairy cows.

Milk production responses of grazing cows offered supplements in different ways were measured. Holstein-Friesian cows, averaging 45 d in milk, were allocated into 8 groups of 24, with 2 groups randomly assigned to each of 4 feeding strategies. These were control: cows grazed a restricted allowance of perennial ryegrass pasture supplemented with milled wheat grain fed in the milking parlor and alfalfa hay offered in the paddock; FGM: same pasture and allowance as the control supplemented with a formulated grain mix containing wheat grain, corn grain, and canola meal fed in the parlor and alfalfa hay fed in the paddock; PMRL: same pasture and allowance as the control, supplemented with a PMR consisting of the same FGM but mixed with alfalfa hay and presented on a feed pad after each milking; and PMRH: same PMR fed in the same way as PMRL but with a higher pasture allowance. For all strategies, supplements provided the same metabolizable energy and grain:forage ratio [75:25, dry matter (DM) basis]. Each group of 24 cows was further allocated into 4 groups of 6, which were randomly assigned to receive 8, 12, 14, or 16 kg of DM supplement/cow per d. Thus, 2 replicated groups per supplement amount per dietary strategy were used. The experiment had a 14-d adaptation period and a 14-d measurement period. Pasture allowance, measured to ground level, was approximately 14 kg of DM/d for control, FGM, and PMRL cows, and 28 kg of DM/d for the PMRH cows, and was offered in addition to the supplement. Positive linear responses to increasing amounts of supplement were observed for yield of milk, energy-corrected milk, fat, and protein for cows on all 4 supplement feeding strategies. Production of energy-corrected milk was greatest for PMRH cows, intermediate for FGM and PMRL cows, and lowest for control cows. Some of these differences in milk production related to differences in intake of pasture and supplement. Milk fat concentration decreased with increasing amount of supplement for all feeding strategies, but the decline was most marked for the control cows. Milk protein concentration increased for all groups as the amount of supplement increased, but was greater for FGM, PMRL, and PMRH cows than control cows. It is concluded that when supplements are fed to grazing dairy cows, inclusion of corn grain and canola meal can increase milk production even at similar metabolizable energy intakes, and that it does not matter whether these supplements are fed as a PMR or in the parlor and paddock.

Herbage intake and milk production of late-lactation dairy cows offered a second-year chicory crop during summer.

Chicory (Cichorum intybus L.) is a summer-active forage herb which has been proposed as an option to increase summer feed supply, increase dry matter intake, nutrient intake, and milk yield from nonirrigated dairy production systems in southern Australia. Dry matter intake, nutrient intake, milk yield, and yield of milk fat and protein of predominantly Holstein-Friesian dairy cows in late lactation consuming 3 herbage-based diets (4 replicates per treatment) were measured. The 3 grazed herbages were second-year chicory (CHIC) and perennial ryegrass (Lolium perenne L.; PRG) monocultures and a mixed sward (~50:50) of chicory and perennial ryegrass (MIX). All diets (CHIC, PRG, and MIX) were supplemented with alfalfa (Medicago sativa L.) hay (5.5kg of DM/cow per day) and an energy-based concentrate pellet (4.0kg of DM/cow per day). There were no significant differences in milk yield (12.0 to 12.6kg/d across the treatments) or the yield of milk fat (539 to 585g/d) and milk protein (433 to 447g/d) between the 3 herbage-based diets. No differences in DMI (17.9 to 19.2kg/d) or estimated metabolizable energy intake (173 to 185MJ/d) were noted between treatments. Estimated metabolizable energy concentrations in the forages on offer were lower in CHIC than PRG (7.6 vs. 8.2MJ/kg of dry matter), but the concentration in consumed herbage was not different (9.1 vs. 9.2MJ/kg of dry matter); as such, potential for increased milk yield in cows offered CHIC was limited. Increased concentration of polyunsaturated fatty acids was observed in chicory herbage compared with perennial ryegrass. This was associated with increased milk conjugated linoleic acid and milk polyunsaturated fatty acids when chicory formed part of the diet (CHIC compared to PRG and MIX). Chicory could be used as an alternative to perennial ryegrass in summer; however, the developmental stage of chicory will influence concentrations of metabolizable energy and neutral detergent fiber and, therefore, intake and milk production responses compared with perennial ryegrass.

Milk production and composition of mid-lactation cows consuming perennial ryegrass-and chicory-based diets.

Dry matter intakes (DMI), nutrient selection, and milk production responses of dairy cows grazing 3 herbage-based diets offered at 2 allowances were measured. The 2 allowances were 20 (low) and 30 (high) kg of dry matter (DM)/cow per day and these were applied to 3 herbage types: perennial ryegrass (PRG) and chicory (CHIC+) monocultures and a mixed sward of chicory and perennial ryegrass (MIX). The CHIC+ diet was supplemented with alfalfa hay (approximately 2 kg of DM/cow per day) to maintain dietary neutral detergent fiber (NDF) concentration and all diets were supplemented with energy-based pellets (6 kg of DM/cow per day). Holstein-Friesian dairy cows averaging 136 ± 30 d in milk were allocated to 4 replicates of the 6 treatments using stratified randomization procedures. Cows were adapted to their experimental diets over a 14-d period, with measurements of DMI, milk yield, and composition conducted over the following 10 d. Herbage DMI was lowest (12.8 vs. 14.0 kg of DM/d) for CHIC+ compared with the MIX and PRG, although total forage intake (grazed herbage plus hay) was similar (14.0 to 15.0 kg of DM/d) across the 3 treatments. Milk production, milk protein, and milk fat concentrations were not different between herbage types. Grazed herbage DMI increased with increasing herbage allowance and this was associated with increased milk protein concentration (3.23 to 3.34%) and total casein production (41.7 to 43.6 mg/g). Concentrations of polyunsaturated fatty acids in milk fat, particularly linoleic acid, were increased in milk from cows offered the CHIC+ or the MIX diets, indicating potential benefits of chicory herbage on milk fatty acid concentrations. Although feeding CHIC+ or MIX did not increase milk yield, these herbage types could be used as an alternative to perennial ryegrass pasture in spring.

Grape marc reduces methane emissions when fed to dairy cows.

Grape marc (the skins, seeds, stalk, and stems remaining after grapes have been pressed to make wine) is currently a by-product used as a feed supplement by the dairy and beef industries. Grape marc contains condensed tannins and has high concentrations of crude fat; both these substances can reduce enteric methane (CH4) production when fed to ruminants. This experiment examined the effects of dietary supplementation with either dried, pelleted grape marc or ensiled grape marc on yield and composition of milk, enteric CH4 emissions, and ruminal microbiota in dairy cows. Thirty-two Holstein dairy cows in late lactation were offered 1 of 3 diets: a control (CON) diet; a diet containing dried, pelleted grape marc (DGM); and a diet containing ensiled grape marc (EGM). The diet offered to cows in the CON group contained 14.0kg of alfalfa hay dry matter (DM)/d and 4.3kg of concentrate mix DM/d. Diets offered to cows in the DGM and EGM groups contained 9.0kg of alfalfa hay DM/d, 4.3kg of concentrate mix DM/d, and 5.0kg of dried or ensiled grape marc DM/d, respectively. These diets were offered individually to cows for 18d. Individual cow feed intake and milk yield were measured daily and milk composition measured on 4d/wk. Individual cow CH4 emissions were measured by the SF6 tracer technique on 2d at the end of the experiment. Ruminal bacterial, archaeal, fungal, and protozoan communities were quantified on the last day of the experiment. Cows offered the CON, DGM, and EGM diets, ate 95, 98, and 96%, respectively, of the DM offered. The mean milk yield of cows fed the EGM diet was 12.8kg/cow per day and was less than that of cows fed either the CON diet (14.6kg/cow per day) or the DGM diet (15.4kg/cow per day). Feeding DGM and EGM diets was associated with decreased milk fat yields, lower concentrations of saturated fatty acids, and enhanced concentrations of mono- and polyunsaturated fatty acids, in particular cis-9,trans-11 linoleic acid. The mean CH4 emissions were 470, 375, and 389g of CH4/cow per day for cows fed the CON, DGM, and EGM diets, respectively. Methane yields were 26.1, 20.2, and 21.5g of CH4/kg of DMI for cows fed the CON, DGM, and EGM diets, respectively. The ruminal bacterial and archaeal communities were altered by dietary supplementation with grape marc, but ruminal fungal and protozoan communities were not. Decreases of approximately 20% in CH4 emissions and CH4 yield indicate that feeding DGM and EGM could play a role in CH4 abatement.

First Report of Aster Yellows Phytoplasma in Soybean in Michigan.

During the summer of 2012, soybean plants in a commercial field in Clinton County, Michigan, exhibited symptoms characteristic of phytoplasmal diseases (1,2). Symptoms included extensive top dieback, stunting, purple stem surfaces, internal necrosis, leaf vein discoloration, and bud proliferation. Approximately 80% of plants in a half hectare along the southern edge of the field were symptomatic, although the majority of plants in the 4-ha field appeared symptomless. Total genomic DNA was extracted from one symptomatic and one asymptomatic leaf sample using a Qiagen DNeasy Plant Mini Kit (Qiagen, Germantown, MD) according to manufacturer's instructions. The DNA was used as template in direct PCR primed by the phytoplasma-universal primers P1/P7 followed by nested PCR primed by P1/AYint (3). Reactions containing template DNA from the symptomatic plant yielded ribosomal RNA gene amplicons of 1.8 kbp (P1/P7-primed) and 1.6 kbp (P1/AYint-primed), respectively. Reactions containing template DNA from the asymptomatic plant or water did not yield amplicons. The products of PCRs primed by P1/P7 were purified using PureLink PCR Purification kit (Life Technologies, Carlsbad, CA) and cloned in a pGem T-Easy vector system (Promega, Madison, WI). Three separate clones were sequenced using the sequencing primers M13For, M13Rev, SAYF nt 755, (5'-AAAGCGTGGGGAGCAAACAG), and SAYR nt 1159, (5'-TTTGACGTCGTCCCCACCTT). The sequences of all three clones were identical. A consensus (Sequencher 4.1, Gene Codes Corporation, Ann Arbor, MI) nucleotide sequence of 1,830 bp was deposited in GenBank under the accession number KF528320. A BLASTn similarity search revealed that the sequence shared 100% identity to rDNA of aster yellows phytoplasma (AF222063). Additionally, analysis of the 16Sr group/subgroup classification, based on in silico RFLP analyses using iPhyClassifier (4), indicated that the soybean phytoplasma is a member of subgroup 16SrI-B aster yellows phytoplasma subgroup. In a phylogenic tree deduced using the neighbor joining algorithm, the phytoplasma consensus sequence obtained from soybean in Michigan clustered with other group 16SrI (aster yellows phytoplasma) strains. While aster yellows phytoplasma has been previously reported in soybean in Wisconsin (2), to our knowledge, this is the first report of aster yellows in soybean in Michigan. References: (1) C. R. Grau et al. Compendium of Soybean Diseases, 4th ed. G. L. Hartman et al., eds. American Phytopathological Society, St. Paul, MN, 1999. (2) M. E. Lee et al. Can. J. Plant Pathol. 24:125, 2002. (3) C. D. Smart et al. Appl. Env. Microbiol. 62:2988, 1996. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

Effects of different strategies for feeding supplements on milk production responses in cows grazing a restricted pasture allowance.

Milk production responses of grazing cows offered supplements in different ways were measured. Holstein-Friesian cows, averaging 227 d in milk, were allocated into 6 groups of 36, with 2 groups randomly assigned to each of 3 feeding strategies: (1) cows grazed perennial ryegrass pasture supplemented with milled barley grain fed in the milking parlor and pasture silage offered in the paddock (control); (2) same pasture and allotment supplemented with the same amounts of milled barley grain and pasture silage, but presented as a mixed ration after each milking (PMR 1); and (3) same pasture and allotment, supplemented with a mixed ration of milled barley grain, alfalfa hay, corn silage, and crushed corn grain (PMR 2). For all strategies, supplements provided the same metabolizable energy and grain:forage ratio. [75:25, dry matter (DM) basis]. Each group of 36 cows was further allocated into 4 groups of 9, which were assigned to receive 6, 8, 10, or 12 kg of supplement DM/cow per day. Thus, there were 2 replicated groups per supplement amount per dietary strategy. The experiment had a 14-d adaptation period and an 11-d measurement period. Pasture allotment was approximately 14 kg of DM/d for all cows and was offered in addition to the supplement. Positive quadratic responses to increasing amounts of supplement were observed for yield of milk, energy-corrected milk (ECM), and fat and protein, and positive linear responses for concentrations of fat and protein for cows on all 3 supplement feeding strategies. No difference existed between feeding strategy groups in yield of milk, ECM, or protein at any amount of supplement offered, but yield and concentration of fat was higher in PMR 2 cows compared with control and PMR 1 cows at the highest amounts of supplementation. Responses in marginal ECM production per additional kilogram of supplement were also greater for PMR 2 than control and PMR 1 cows when large amounts of supplement were consumed. For all diets, marked daily variation occurred in ruminal fluid volatile fatty acids and pH, especially in cows fed the largest amounts of supplement. It was concluded that when supplements are fed to grazing dairy cows, a simple mix of grain and pasture silage has no benefit over traditional strategies of feeding grain in the parlor and forage in the paddock. However, yield of milk fat and marginal milk production responses can be greater if the strategy uses an isoenergetic ration that also contains alfalfa hay, corn silage, and corn grain.

Effects of feeding algal meal high in docosahexaenoic acid on feed intake, milk production, and methane emissions in dairy cows.

This study examined effects on milk yield and composition, milk fatty acid concentrations and methane (CH4) emissions when dairy cows were offered diets containing different amounts of algal meal. The algal meal contained 20% docosahexaenoic acid (DHA) and cows were offered either 0, 125, 250, or 375 g/cow per d of algal meal corresponding to 0, 25, 50, or 75 g of DHA/cow per d. Thirty-two Holstein cows in mid lactation were allocated to 4 treatment groups, and cows in all groups were individually offered 5.9k g of dry matter (DM) per day of concentrates [683 g/kg of cracked wheat (Triticum aestivum), 250 g/kg of cold-pressed canola, 46 g/kg of granulated dried molasses, and 21 g/kg of mineral mix] and ad libitum alfalfa (Medicago sativa) hay. The algal meal supplement was added to the concentrate allowance and was fed during the morning and afternoon milking, whereas the alfalfa hay was fed individually in pens. Cows were gradually introduced to their diets over 7d and then fed their treatment diets for a further 16d. Dry matter intake and milk yield were measured daily, and milk composition was measured on a sample representative of the daily milk yield on Thursday of each week. For the last 2d of the experiment, cows were individually housed in respiration chambers to allow measurement of CH4 emissions. Dry matter intake, milk yield and milk composition were also measured while cows were in the respiration chambers. Cows ate all their offered concentrates, but measured intake of alfalfa decreased with increasing dose of DHA by 16.2, 16.4, 15.1, and 14.3 kg of DM/d, respectively. Milk yield (22.6, 23.5, 22.6, and 22.6 kg/cow per d) was not affected by DHA dose, but milk fat concentrations (49.7, 37.8, 37.0, and 38.3g/kg) and, consequently, milk fat yields (1.08, 0.90, 0.83, and 0.85 kg/d) decreased with addition of DHA. The feeding of algal meal high in DHA was associated with substantial increases in the concentrations of DHA (0.04, 0.36, 0.60, and 0.91 g/100g of milk fatty acids) and conjugated linoleic acid C18:2 cis-9,trans-11 (0.36, 1.09, 1.79, and 1.87 g/100g of milk fatty acids). Addition of DHA did not affect total emissions of CH4 (543, 563, 553, and 520 g/cow per d), nor emissions in terms of milk production (24.9, 22.1, 24.3, and 23.4 g of CH4/kg of milk), but emissions were increased with respect to total intake (22.6, 23.5, 24.5, and 24.4 g of CH4/kg of DM). These findings indicate that CH4 emissions were not reduced when dairy cows were fed a forage-based diet supplemented with DHA from algal meal.

First Report of Soybean vein necrosis virus on Soybeans in Michigan.

Soybean vein necrosis virus (SVNV) is associated with an emerging disease in soybean producing regions of the United States. Soybean leaves with necrotic vein symptoms were initially noted in 2008 or 2009 in fields across Arkansas, Kansas, Missouri, Illinois, Mississippi, Tennessee, and Kentucky and SVNV was determined to be the causal agent (2). In 2012, widespread reports of SVNV were made across most soybean (Glycine max) producing states including the recent confirmation of SVNV in Iowa and Wisconsin (1). Foliar symptoms similar to those reported for SVNV were observed at approximately 1 to 10% incidence in soybean fields across Michigan in late August and September of 2012, including fields located in Cass, Ingham, Midland, Saginaw, and Van Buren counties. Symptoms included chlorosis and necrosis which initiated on the veins with subsequent spread across the leaf. An initial sample collected from the East Lansing Agricultural Research Station was confirmed to have SVNV with a polyclonal antibody using double antibody sandwich (DAS)-ELISA at AC Diagnostics, Inc. (Fayetteville, AR) and with reverse transcription PCR by Ioannis Tzanetakis, University of Arkansas, Fayetteville. Additional samples from five fields were subsequently collected from Cass, Ingham, and Van Buren counties. Duplicate leaf tissue samples were tested with DAS-ELISA using the SVNV test kit (AC Diagnostics). All symptomatic leaf samples exhibited a strong positive reaction based on the optical density reading at 405 nm. Absorbance reading that exceeded the healthy soybean tissue by a standard deviation of +3× were considered positive. Total RNA was also extracted from each sample using the RNeasy Plant Mini Kit (Qiagen, Germantown, MD). Complementary DNA (cDNA) was generated using virus-specific LdetR and SdetR primers (2) with the High Capacity RT cDNA kit (Life Technologies; Carlsbad, CA). The cDNA was used as template for PCR with the SVNV-specific primers that amplify regions of the L (LdetF/LdetR) and the S (SdetF/SdetR) RNAs (1). Amplification products of the expected 297 and 861 bp size, respectively, were detected in all symptomatic samples while no amplification products were generated from healthy soybean plant tissues grown under greenhouse conditions. Significantly, this is the first documentation and confirmation of the widespread prevalence of SVNV across the state of Michigan in 2012. References: (1) D. L. Smith et al. Plant Dis. http://dx.doi.org/10.1094/PDIS-11-12-1096-PDN . (2) J. Zhou et al. Virus Genes 43:289, 2011.

Filling the out of season gaps for lamb and hogget production: Diet and genetic influence on carcass yield, carcass composition and retail value of meat.

This study investigated the use of camelina forage and meal supplementation to a finishing diet on carcass traits, composition and retail value of lamb and hoggets. The metabolisable energy and crude protein concentrations of all 3 diets were 10-11 MJ/kg DM and 14-15% CP. Thirty maternal Composite wether lambs (28-38 kg) and 30 Merino wether hoggets (37-43 kg) were used in a 3 × 2 factorial experiment. Animals were slaughtered after 10 weeks of feeding with carcasses classified as 'Heavy lamb' or 'Heavy hogget' (>22 kg carcass weight). Carcass traits, composition, meat mineral concentrations and retail colour were measured. Camelina diets increased liveweight (P < 0.02) and carcass weight (P < 0.002) for both sheep types. Carcass weight (P < 0.005) and dressing % (P < 0.01) were lower for Merino hoggets than Composite lambs. Mineral concentration and retail colour stability of fresh meat were unaffected by diet, with 72 h retail colour considered acceptable for consumers.

Production of and in vitro response to interleukin 2 in the acquired immunodeficiency syndrome.

To test the hypothesis that deficient interleukin 2 (IL-2) secretion may underlie the impaired capacity of T cells from patients with Acquired Immunodeficiency Syndrome (AIDS) and the AIDS-related complex (ARC) to generate the macrophage-activating lymphokine, gamma interferon (IFN-gamma), we used five specific microbial antigens to examine IL-2 production. Mononuclear cells from only one of 32 (3%) AIDS patients secreted normal levels of IL-2, and 21 (66%) failed to produce any detectable IL-2. For 36 ARC patients, IL-2 generation was normal in nine (25%) and absent in 11 (31%). Given these results, recombinant (r) IL-2 was tested for its capacity to stimulate or enhance IFN-gamma production. rIL-2 (10 U/ml) alone stimulated cells from controls, ARC, and AIDS patients to secrete 93 +/- 25, 99 +/- 33, and 7 +/- 3 U/ml of IFN-gamma, respectively. rIL 2 (10 U/ml) plus antigen induced no change in mean IFN-gamma levels for controls, a 4.4-fold increase for 17 AIDS patients (16 +/- 16 vs. 71 +/- 21 U/ml), and a 7.2-fold increase (18 +/- 5 vs. 130 +/- 27 U/ml) for 19 ARC patients with abnormal IFN-gamma generation to antigen alone. Individual responses indicated that six of the 17 (35%) AIDS patients with opportunistic infections and 12 of the 19 (63%) with ARC were apparent responders to 10-100 U/ml of rIL-2. These results (a) document profound impairment in antigen-induced IL-2 secretion by AIDS and ARC T cells, (b) indicate that, in vitro, mononuclear cells from certain patients can respond to rIL-2 with enhanced IFN-gamma production, and thus (c) suggest that in selected patients rIL-2 might have a potentially beneficial therapeutic (AIDS) or prophylactic (ARC) effect against opportunistic infections.

The use of oxidative stress biomarkers in live animals (in vivo) to predict meat quality deterioration postmortem (in vitro) caused by changes in muscle biochemical components.

This study was conducted to determine whether circulating concentrations of blood isoprostanes can be used as an effective biomarker in lambs to predict degradation of color and/or lipid stability in meat. Lambs ( = 84) were fed diets of either lucerne pasture, annual ryegrass pasture, a commercial feedlot pellet, or a combination of annual ryegrass and feedlot pellet for 8 wk, including a 2-wk adaptation period. Blood isoprostane concentration at wk 0, 4, 6 or 8 of feeding was determined. Blood isoprostane concentration for each animal was then correlated with muscle biochemical components that impact color and/or lipid oxidative status during retail display. This included lipid oxidation levels in muscle assessed by thiobarbituric acid reactive substances and meat redness determined by a HunterLab colorimetric spectrometer. Lambs that consumed the commercial feedlot pellet had a lower muscle vitamin E level (< 0.01) and a greater level of -6 PUFA ( < 0.001) compared with lambs finished on annual ryegrass or lucerne. Lipid oxidation levels were greatest for lambs finished on the feedlot ration, lowest in lambs finished on the ryegrass diet, and intermediate for lambs finished on lucerne and ryegrass-feedlot combination ( < 0.01). After 8 wk of feeding, blood isoprostane concentration was positively correlated with lipid oxidation of meat displayed for 72 h in simulated retail conditions ( < 0.01). There was a negative linear relationship between isoprostane concentration and muscle vitamin E concentration ( = 0.07), lipid oxidation and muscle vitamin E concentration ( < 0.01) but a positive linear relationship between isoprostane concentration and muscle -6 PUFA ( < 0.001) or lipid oxidation and muscle -6 PUFA concentration ( < 0.001). Blood isoprostane concentration and lipid oxidation in meat were influenced by muscle vitamin E and -6 PUFA but not by -3 PUFA. There was no significant relationship observed between blood isoprostane concentration at 0, 4, 6 or 8 wk feeding vs. overall meat color (redness of meat) at 0 and 72 h of display, stored under simulated retail conditions. The results indicate that circulating blood isoprostane concentration can be a useful tool to predict the oxidative status of postmortem meat. Future work will examine the impact of this relationship on meat flavor/aroma deterioration post farm.

Approaches to defining the mechanism of enhancement by Fluosol-DA 20% with carbogen of melphalan antitumor activity.

Fluosol-DA with carbogen (95% oxygen and 5% carbon dioxide) breathing can increase the efficacy of melphalan. Addition of Fluosol-DA to treatment with melphalan leads to a greater increase in tumor growth delay under conditions of air breathing and carbogen breathing than does the fat emulsion Intralipid. The ability of melphalan to kill tumor cells increased with dose over the range of drug examined. At the lower doses of drug there is some increase in tumor cell killing seen with the addition of carbogen breathing or Fluosol-DA and air breathing; however, at the highest dose of the drug this difference disappeared. Throughout the melphalan dosage range examined there is approximately 1 log greater tumor cell kill observed with the addition of Fluosol-DA and carbogen breathing compared to the drug treatment alone. There was no significant difference in the survival of bone marrow cells under any of the treatment conditions. Fluosol-DA itself with air or carbogen breathing produced no detectable cross-links in DNA from tumors treated in vivo. The cross-linking factors for melphalan with air or carbogen breathing and for melphalan plus Fluosol-DA and air breathing were similar; when carbogen breathing was added to the treatment combination, the cross-linking factor increased almost 3-fold. When melphalan was dissolved in Fluosol-DA, the melphalan moved quickly into the lipophilic perfluorochemical particles so that after 1 h 60% of the drug was in the perfluorochemical layer. At 24 h, 85-90% of the melphalan was sequestered in the perfluorochemical particles. The pharmacokinetics of [14C]melphalan alone, [14C]melphalan plus Fluosol-DA, and [14C]melphalan prepared in Fluosol-DA were studied in several tissues of FSaIIC fibrosarcoma-bearing mice. In general, the tissue absorption and distribution t1/2s for melphalan were shortened in the presence of Fluosol-DA (except for kidneys). Shifting the t1/2s for absorption and distribution to shorter times produces a much sharper and earlier peak in the drug exposure of the tumor. Fluosol-DA provides a relatively nontoxic means of increasing oxygen delivery to tumors and a therapeutically meaningful way of improving melphalan antitumor activity.

Intracellular distribution of a platinum-rhodamine 123 complex in cis-platinum sensitive and resistant human squamous carcinoma cell lines.

The platinum(II) tetrachlorodianion and two molecules of rhodamine-123 associate to form a neutral tight ion pair. To examine the intracellular fate of this ionic complex, the levels of uptake after a 1-hr exposure to a 100 microM concentration of each component of the complex, the complex itself and cis-diamminedichloroplatinum(II) (CDDP) were measured in SCC-25 cells. The uptake of Pt(Rh-123)2 was measured by two independent methods: fluorescence and 195mPt gamma-counting. There was excellent agreement between these two methods as to the amount of Pt(Rh-123)2 which was taken up by the cells, indicating that the Pt(Rh-123)2 is probably entering cell intact. Association with Rh-123 increased the amount of platinum which entered the cells by about 70-fold compared to CDDP and increased by about 700-fold the amount of platinum which entered the cells compared to K2PtCl4. The subcellular distributions of Pt(Rh-123)2, Rh-123, CDDP and K2PtCl4 were also examined. When measured by fluorescence or 195mPt gamma-counting, 40-54% of the Pt(Rh-123)2 was in the nuclei of the SCC-25 or SCC-25/CP cells and 27-35% was in the cytosol of the cells. There was excellent agreement between the findings of fluorescence and 195mPt gamma-counting regarding the amount of Pt(Rh-123)2 in each of the subcellular fractions immediately after incubation with the drug and over the time course of observation after drug removal, indicating that the Pt(Rh-123)2 is probably remaining largely intact intracellularly. On a per mg protein basis, there was about a 55-fold greater amount of platinum in the nuclei of the SCC-25 cells exposed to Pt(Rh-123)2 compared to cells exposed to CDDP. In the SCC-25/CP cells, there was about 258-fold greater platinum in the nuclei of cells exposed to Pt(Rh-123)2 than those exposed to CDDP because CDDP was taken up to a much lesser extent by the SCC-25/CP cells. Association of Rh-123 with potassium tetrachlorodianion forms a tight ion pair, which enters cells in relatively high amounts and is selectively concentrated in the nuclei of the cells.