Analysis of IgG response to experimental infection with RH Toxoplasma gondii in goats.

The IgG response of goats experimentally infected with RH Toxoplasma gondii has been analysed using an indirect ELISA and Western-blot analysis. Specific IgG antibodies were first detected at 14 days post-inoculation (p.i.), reaching a peak by day 35 p.i. and showing slight fluctuations until the end of the experiment (91 p.i.). Specific IgG showed a reactivity over a whole range of peptides (125-24 kDa approximately), but the highest reactivity was observed against a group of antigens with a molecular weight between 34 and 28 kDa, in particular against a 30 kDa fraction which is considered to represent the major surface protein of T. gondii named p30 or SAG-1.     

Thermal and Moisture Diffusion Properties of Amaranth Seeds

The physical characteristics, thermodynamic and transport properties of amaranth seeds relevant to the modelling and simulation of the drying processes of these seeds were studied. The water activity as a function of the temperature and moisture content was modelled by means of the Henderson's expression from water activity experimental data. The desorption–vaporisation heat was also calculated. From the solution to Fick's second law for a spherical geometry and assuming equilibrium conditions at the solid–gas interface, an effective diffusion coefficient was evaluated from experimental drying curves obtained in a moisture chamber. The effect of taking into account more than one term in the Fourier series solution was analysed and it is concluded that the diffusion coefficient corresponding to two terms in the series leads to better agreement with the experimental results for short times.     

Variation and genetic diversity for gliadins in Spanish spelt wheat accessions

Gliadin composition has been analysed in 403 accessions of spelt wheat (Triticum aestivum ssp. spelta); 61 different patterns were found for the -gliadins, 44 for the -gliadins, 19 for the -gliadins and 15 for the -gliadins. A subset of 333 accessions belonging to fifty populations from Asturias, North of Spain, showed high levels of genetic variation (A = 3.89, P = 0.88, Ne = 3.35 and He = 0.553), indicating that 82.5% of the genetic variation was within populations, and only 18.5% among populations. Thirty-five of these populations presented more of five accessions, in this new subset the values of genetic variation were higher that those of fifty populations (A = 4.49, P = 0.91, Ne = 3.80 and He = 0.595). The genetic variation within populations was 59.7% of the total, and 40.3% among populations, which could be associated to fixation effects of some alleles by genetic drift.     

Intra- and interpopulation diversity for HMW glutenin subunits in Spanish spelt wheat

The diversity of HMW glutenin subunits in spelt wheat, Triticum aestivum ssp. spelta, was studied electrophoretically in 333 accessions grouped in 50 populations originally collected from Asturias, North of Spain, in 1939. The inter- and intra-population distribution of HMW glutenin alleles at the Glu-A1, Glu-B1 and Glu-D1 loci were investigated. The results show that the genetic variation in HMW glutenin subunits is mainly present within populations, being the variation between populations only 21%. The materials analysed showed a wide polymorphism for the HMW glutenin subunits, although some allelic variants were clearly dominant. This suggests the possibility of a loss of variability before the collection that could have increased with the subsequent reduction of the cultivation area of this species in this Spanish region.     

The importance of dietary HUFA for meagre larvae (Argyrosomus regius; Asso, 1801) and its relation with antioxidant vitamins E and C

Despite the interest of meagre (Argyrosomus regius) as a fast‐growing candidate for Mediterranean aquaculture diversification, there is a lack of information on nutrition along larval development. Importance of highly unsaturated fatty acids (HUFA) and the antioxidant vitamins E and vitamin C has not been investigated yet in this species. Six diets with two levels of HUFA (0.4% and 3% dw), two of vitamin E (1500 and 3000 mg kg^?1) and two of vitamin C (1800 and 3600 mg kg^?1) were fed to 15 dah meagre larvae. Larval growth in total length and dry body weight was significantly lowest in larvae fed diet 0.4/150/180 and showed few lipid droplets in enterocytes and hepatocytes and lower HUFA contents than the initial larvae. Increase in dietary HUFA up to 3%, significantly improved larval growth and lipid absorption and deposition. Besides, among fish fed 3% HUFA, increase in vitamin E and vitamin C significantly improved body weight, as well as total lipid, 22:6n‐3 and n‐3 fatty acids contents in the larvae. Thus, the results showed that 0.4% dietary HUFA is not enough to cover the essential fatty acid requirements of larval meagre and a high HUFA requirement in weaning diets is foreseen for this species. Besides, the results also pointed out the importance of dietary vitamin E and C to protect these essential fatty acids from oxidation, increase their contents in the larvae and promote growth, suggesting high vitamin E and C requirements in meagre larvae (higher than 1500 and 1800 mg kg^?1 for vitamin E and vitamin C respectively).     

Genetic variation for waxy proteins and amylose content in Spanish spelt wheat (<Emphasis Type="Italic">Triticum spelta</Emphasis> L.)

Spelt wheat is a neglected crop that could be used in the quality breeding of modern common wheat. One important aspect of this quality is the starch composition which is related to the waxy proteins. A collection of 420 accessions of Spanish spelt wheat was analysed for waxy protein composition by SDS–PAGE. Polymorphism was found in the three waxy proteins, detecting differences both in size and in activity, and a new waxy allele (Wx-D1g) was identified. Seed amylose content was also determined and significant differences were detected among the different allelic combinations. In general, the accessions carrying one or two waxy null alleles showed less amylose content. The variation found could be used to enlarge the genetic pool of common wheat, or to develop lines of spelt with different levels of amylose content.     

In Vitro Fertilization (IVF) in Straws and a Short Gamete Coincubation Time Improves the Efficiency of Porcine IVF

The present study was designed to evaluate three different in vitro fertilization (IVF) systems: a straw‐IVF system with 10 min of coincubation, a straw‐IVF system with 6‐h coincubation and the microdrop‐IVF system with 6‐h coincubation (the traditional IVF system used routinely in most of IVF laboratories) in an attempt to reduce polyspermic penetration ( Experiment 1 ). When the straw‐IVF system was tested in combination with two coincubation times, the use of 10 min of coincubation significantly increased (p < 0.001) the penetration rate and the efficiency of fertilization (67.7 ± 6.4% vs 31.9 ± 6.5% and 41.5 ± 2.5% vs 17.6 ± 2.5% for 10 min and 6 h, respectively), while there were no significant differences in the incidence of monospermy between both systems (64.3 ± 5.1% and 67.7 ± 3.4%, for 10 min and 6 h, respectively). The penetration rate in the 6‐h microdrop‐IVF system was higher (93.8 ± 3.6%; p < 0.001) compared with the 10‐min straw‐IVF system (67.7 ± 6.4%), however, monospermy was severely reduced (25.0 ± 4.3% vs 67.7 ± 3.4%, for the 6‐h microdrop‐IVF system and 10‐min straw‐IVF system, respectively). The efficiency of the IVF showed similar values between microdrop and 6‐h straw‐IVF systems, but efficiency was significantly improved (p < 0.05) when the 10‐min straw‐IVF system was used. Experiment 2 was designed to compare porcine in vitro embryo production in two IVF systems, the 6‐h microdrop‐IVF system (1000 sperm per oocyte) and 10‐min straw‐IVF system (30 000 sperm per oocyte). The blastocyst formation rates tended (p = 0.06) to be higher when the 10‐min straw‐IVF system was used compared with the 6‐h microdrop‐IVF system. In addition, the number of total cells per blastocyst increased significantly (p < 0.05) in the 10‐min straw‐IVF system. These results showed that the 10‐min straw‐IVF system is an effective way to decrease polyspermic penetration, and improve the efficiency of fertilization and the quality of blastocysts in terms of cell number per embryo.     

Effects of feed intake on in situ rumen microbial contamination and degradation of feeds

An in situ study was conducted using four rumen cannulated wethers and five feeds (corn grain (CG), soybean meal (SBM), sunflower meal (SFM), vetch–oat hay (VH), and lentil straw (LS)) to determine (using ¹⁵N infusion techniques) the effects of two intake levels (40 and 80 g DM/kg W^0.75) on the microbial contamination and rumen degradation of DM or CP. Degradation studies were also performed for neutral and acid detergent fibres (NDF and ADF, respectively) of VH. In most cases, the evolution with time of the microbial DM adhered to particles fitted well to exponential curves, which diverged between both levels of intake due to the lower values attained at high intake. However, as a consequence of the large and progressive increase of the variability of microbial contamination, statistical evidence is only partial. This behaviour was less evident for CP contamination, especially in forages. The lack of these corrections underestimated (P < 0.001) the effective degradability (ED) of all tested fractions, with important differences between feeds. The intake level had not relevant effects on the distribution of soluble, insoluble available and unavailable fractions of DM or CP (or fibres in VH), but determined some changes in their degradation rates (k_d). Direct relations between these last values and rumen outflow rates (k_p) were shown in some feeds for the degradation of CP and also of DM in concentrates, whereas negative relations were shown for the degradation rates of DM in forages (or NDF and ADF of VH). All ED estimates decreased with the intake rise, but for CP this effect (P < 0.05) was only detected in SBM and VH. These decreases represent 40.8 (CG), 80.8 (SBM), 62.1 (SFM), 66.8 (VH), and 19.5% (LS) than those estimated considering only k_p changes, which shows the interest to consider conjointly the variations of both rates to study the effect of diet changes on ED.     

Development of short-snouted seahorse (<Emphasis Type="Italic">Hippocampus hippocampus</Emphasis>, L. 1758): osteological and morphological aspects

Information about early development after male release lags behind studies of juveniles and adult seahorses, and newborn seahorses, similar in shape to adults, are considered juveniles or fry. During early life, Hippocampus hippocampus present behavioural (shift in habitat, from planktonic to benthic) and morphological changes; for this reasons, the aims of this study are to define the stage of development of H. hippocampus after they are expelled from the male brood pouch and to establish direct or indirect development through an osteological analysis. The ossification process was studied in 120 individuals, from their release to 30 days after birth. To analyse the osteological development, Alcian Blue-Alizarin Red double staining technique for bone and cartilage was adapted to this species. At birth, H. hippocampus presents a mainly cartilaginous structure that ossifies in approximately 1 month. The bony armour composed of bony rings and plates develops in 10 days. The caudal fin, a structure absent in juveniles and adult seahorses, is present at birth and progressively disappears with age. The absence of adult osteological structure in newborns, like coronet, bony rings and plates, head spines and components allowing tail prehensile abilities, suggests a metamorphosis before the juvenile stage. During the indirect development, the metamorphic stage started inside brood pouch and followed outside and leads up to reconsider the status of H. hippocampus newborns.