Milk ejection during automatic milking in dairy cows

Tactile stimulation (manual or mechanical) of the mammary gland causes alveolar milk ejection through a neuro-endocrine reflex arc (Dzidic et al., 2004). Oxytocin is the hormone that induces the contraction of the myoepitelial cells surrounding the alveoli

Feeding behaviour, digestibility, energy balance and productive performance of lactating goats fed forage-based and forage-free diets

Six lactating Saanen goats have been used in a Latin Square design to evaluate a grass-based diet (G), a hay-based diet(H) and a nonforage diet (NF). On dry matter, grass and hay contributed for 55% of the diets and had 13.7 and 16.1%CP, 55.4 and 49.4% NDF, 38.0 and 31.6% ADF, respectively. Diet NF had beet pulp, cracked carob beans and whole cottonseedas main ingredients, with more than 75% of the particles greater than 2 mm.Independently of the dietary treatment, the goats spent more time eating than ruminating. Diet NF proved to be effectivein stimulating chewing activity, despite a trend for a lower chewing activity for eating (178, 185, 125 min/kg DMIfor diets G, H and NF, respectively), but not for ruminating (84, 80, 80 min/kg DMI for diets G, H and NF, respectively).Feed intake did not differ among diets, while regarding digestibility diet NF had the highest values for DM (74.1%), OM(75.7%) and non-fibrous carbohydrates (92.0%), but the lowest for ADF (44.5%). For treatments G, H and NF milk yieldswere 3011, 3688 and 3212 g/d (P<0.05 between H and G), while milk fat and protein were respectively 3.37, 3.24,2.96% (P<0.05 between G and NF) and 3.11, 3.32, 3.29%. Milk urea N was lower for diet NF (18.8, 18.6, 12.7 mg/100ml, P<0.001). Diet NF increased the concentration of the short chain fatty acids of milk fat and decreased the content ofC18:0, C18:1 and C18:3 in comparison to the other two diets. No difference among treatments was recorded for CLA.Intake energy was digested to a lesser extent for diet G (68.9, 70.0, 72.7%, P<0.05 between G and NF) due to its poorquality forage. Urinary energy losses reflected the corresponding protein contents of the diets, while no difference wasrecorded for methane production. ME resulted higher for diet NF (60.0, 60.7, 65.1% of the intake energy, P<0.01), whileheat production and milk energy yield were similar in the three treatments. Diet NF had a higher ME content (11.13,11.26, 11.93 MJ/kg DM, P<0.05), while no significant difference among the diets was recorded in terms of kl (0.64, 0.70,0.69) and NEl (7.20, 7.93, 8.30 MJ/kg DM).It is concluded from the study that a nonforage diet with an adequate amount of structured fibre could substitute a rationbased on poor quality forage in lactating goats; however, good forage seems to enhance milk performance to a greaterextent

New Avoparcin-like Molecules from the Avoparcin Producer Amycolatopsis coloradensis ATCC 53629

Amycolatopsis coloradensis ATCC 53629 is the producer of the glycopeptide antibiotic avoparcin. While setting up the production of the avoparcin complex, in view of its use as analytical standard, we uncovered the production of a to-date not described ristosamynil-avoparcin. Ristosamynil-avoparcin is produced together with α-and β-avoparcin (overall indicated as the avoparcin complex). Selection of one high producer morphological variant within the A. coloradensis population, together with the use of a new fermentation medium, allowed to increase productivity of the avoparcin complex up to 9 g/L in flask fermentations. The selected high producer displayed a non-spore forming phenotype. All the selected phenotypes, as well as the original unselected population, displayed invariably the ability to produce a complex rich in ristosamynil-avoparcin. This suggested that the original strain deposited was not conforming to the description or that long term storage of the lyovials has selected mutants from the original population

Crecimiento de renuevos y expansión de copas en claros del dosel de bosques de Nothofagus pumilio (lenga) en Chubut, Patagonia, Argentina

In the province of Chubut in Patagonia, Argentina, Nothofagus pumilio forests (locally known as lenga), are managed through selective cuts, which imply the opening of canopy gaps. This management scheme is carried out without taking into consideration the sapling requirements changes through neither a cutting cycle nor the precipitation gradient in which these forests thrive. To analyze these changes, we inferred the facilitation-competition balance between the canopy and regeneration studying the effects of precipitation levels, gap size and gap age on saplings growth in height on 45 canopy gaps artificially created between 1960 and 1993. Results shown that during the first 20 years since the gap opening, the regeneration growth is determined by light availability in mesic sites and by water availability in dry sites. However, the difference due to the precipitation levels gradually decreases over time. Moreover, in the period between 20 and 35 years after gap opening, in both mesic and xeric sites, light is the limiting factor to growth. This means that in xeric sites, saplings shift from a water-dependent to a light-dependent growth. The average closing rate of gaps due to lateral growth of trees bordering the gap is high enough so that within the proposed gap size range, the gap healing can occur before regeneration reaches the upper stratum. Consequently, in mesic sites the gap opening can be done by a single operation that generates gaps with diameters of approximately twice the average height of the canopy (D/H). While in xeric environments, lenga seedling establishment and initial growth require the cover of small gaps, but advanced regeneration requires bigger gaps to reach the canopy. For this reason, gaps should be opened in two stages: the first gaps should be opened with a D/H between 0.8 and 1, and after a cutting cycle of 35 years, these openings should be enlarged to a D/H between 1.5 and 2. The close relationship is maintained between the new cohort and the upper strata require special considerations regarding the evolution of the balance between positive and negative interactions during development. Our work highlights the need to adjust management practices to these spatial and temporal variations so as to achieve an optimal growth along the entire production cycle.En la provincia del Chubut, Patagonia Argentina, los bosques de Nothofagus pumilio (lenga) son manejados mediante cortas de selección, que implican la apertura de claros en el dosel. Este esquema de manejo es implementado sin tener en cuenta los requerimientos de los renuevos a lo largo de todo el ciclo de cortas ni el gradiente de precipitaciones presente en su distribución. Para analizar estos aspectos estimamos el balance facilitación-competencia entre el dosel y la regeneración, considerando los efectos de los niveles de precipitación, el tamaño de los claros y la antigüedad de los mismos, en 45 claros creados artificialmente entre los años 1960 y 1993. Los resultados muestran que durante los primeros 20 años desde la apertura del claro, el crecimiento de la regeneración está determinado por la disponibilidad de luz en los sitios mésicos y por la disponibilidad de agua en los sitios xéricos. Sin embargo, la diferencias entre los distintos niveles de precipitación decrece gradualmente a lo largo del tiempo y entre los 20 a 35 años luego de la apertura de los claros, tanto en los sitios mésicos como xéricos el factor limitante es la luz. Esto implica que en los sitios xéricos el crecimiento de los renuevos pasa de ser dependiente del agua a dependiente de la luz. Por otro lado, la tasa de cierre de los claros debida al crecimiento lateral de la copa de los árboles límite es lo suficientemente grande como para que pueda ocurrir el cierre antes de que los renuevos alcancen el estrato superior. Por lo tanto, en los sitios mésicos la apertura de los claros puede realizarse en una única operación que genere claros con un diámetro de aproximadamente el doble de la altura dominante del bosque (D/H ≈ 2). Por el contrario, en los sitios xéricos, el establecimiento y crecimiento inicial de los renuevos requiere la apertura de claros pequeños (D/H entre 0,8 y 1) que luego deberán ser ampliados para maximizar el crecimiento avanzado (D/H entre 1,5 y 2). La estrecha relación entre la regeneración y el dosel del bosque requiere la consideración de los posibles cambios en el balance entre los apsectos positivos y negativos de la misma a lo largo de todo su desarrollo. Nuestro trabajo resalta la necesidad de ajustar las prácticas de manejo a estas variaciones espaciales y temporales para alcanzar un desarrollo óptimo a lo largo del todo el ciclo productivo

Effects of a nonforage diet on milk production, energy and nitrogen metabolism in dairy goats throughout lactation

The objective of the experiment was to compare a silage-based control diet (C) with a nonforage diet (NF) in dairy goats throughout lactation in terms of animal performance and energy utilization. Eight Saanen goats were divided into two groups and fed C or NF, a commercial blend that included sunflower meal, cassava, coconut meal, and whole cottonseeds as the main ingredients that was characterized by a small particle size and a high crude protein content. In early, mid, and late lactation (44, 100, and 219 days in milk) the goats were individually tested for dry matter intake (DMI), digestibility, milk yield and composition, milk renneting properties, rumen and plasma parameters, and nitrogen and energy utilization (open circuit respiration chambers). During early and mid lactation, the NF fed goats had a very high DMI: 2946 and 2915 g/ d, respectively. Nevertheless, milk yield was similar for the two treatments: 4369 vs. 4342 and 3882 vs. 3841 g/d for goats fed diets C and NF during the first and second periods, respectively. Milk fat content was not statistically different between the two diets. The protein content and rheological parameters of milk were similar for the two diets. Nonprotein nitrogen and urea levels in milk of goats fed NF were significantly higher than goats fed C. Ruminal ammonia and plasma urea nitrogen were also significantly increased by diet NF, due to its high protein content. Plasma glucose, \u3b2-hydroxybutyrate, and nonesterified fatty acids and ruminal volatile fatty acids were not influenced by dietary treatment. Dietary NF significantly decreased energy digestibility (74.5 vs. 65.8%, on average for the lactation, for C and NF, respectively) and had a significantly lower metabolizability (metabolizable energy/intake energy; 66.6 vs 58.0%, on average); however, the efficiency of utilization of metabolizable energy was unaffected by the diet. In conclusion, goats were fed a nonforage diet during the entire lactation without detrimental effect on their health and productive performance

Enhancement of a pentacyclic tyrosine kinase inhibitor production in Cladosporium cf. cladosporioides by Cladosporol

The binaphthyl derivative cladosporol A was supplied from 60 to 200 mg l 121 to shaken cultures of Cladosporium cf. cladosporioides. Compared to blank, fungal biomass was not affected by adding cladosporol till 100 mg l 121: it rather increased at higher ratios between 150 and 200 mg l 121. The production of the major pentacyclic metabolite 1, a cytokine production and tyrosine kinase inhibitor, was enhanced tenfold when cladosporol was supplied at the highest ratio (200 mg l 121) to shaken growing cultures of the fungus. The bioconversion of cladosporol to cladosporol D through reductive cleavage of the epoxide group was also observed. Interest in this kind of metabolites lies in their potential activity vs DNA topoisomerase I

Quali-Quantitative Analysis by LC/DAD and GPC of the Polyphenols ofUva Di Troia Canosina Grape Seeds for the Development of an IndustrialNutraceutical Product

The quali-quantitative determination of the principal components of "uva di Troia canosina" seed extracts by LC/ DAD analysis and the optimization of the extraction and purification processes for the development of an industrial nutraceutical product, are described. Two different fractions of seeds collected at different stages of fermentation were compared: "Tesi" 2 when there is a spontaneous stratification of the seeds at the bottom of the recipient and "Tesi" 4 at the end of fermentation. Percolation was applied and compared to maceration and the purification step carefully evaluated to obtain extracts free of contaminant species endowed with polyphenolic content comparable to commercial preparations such as Leucoselect® (Indena, SpA, Italy), Vitis Vinifera extract 95% (seeds), Vitis Vinifera dry extract 95%, Biovin grape seed and vinasse extract. (Farmalabor, Italy). In particular, "Tesi" 2 extract obtained by percolation and purified with a LLE extraction with ethyl acetate showed a polyphenolic content similar to Leucoselect®. From the quantitative analyses it was evident, as expected, that "Tesi"2 has a higher polyphenolic content compared to "Tesi" 4, because during vinification the must extracts polyphenols from the seeds. On the other hand, "Tesi" 4 is particularly convenient since it is easily obtained and very economical, being a waste product. The residual content of organic solvents (ethanol and ethyl acetate) and water was assessed in the grape extracts according to ICH rules by means respectively of HS/GC and Karl Fisher titration in order to meet the requirements for commercialization. Furthermore, the high molecular weight polyphenolic fraction of our extracts was investigated through gel permeation chromatography (GPC) and compared to that of Leucoselect®