Histochemical and Morphometric Analyses of the Musculature of the Forelimb of the Subterranean Rodent Ctenomys talarum (Octodontoidea)

Histochemical and morphometric analyses were performed to characterize the fibre‐type composition of two forelimb muscles of the South American subterranean rodent Ctenomys talarum. The studied muscles were the triceps lateralis, an extensor of the elbow, and the teres major, a flexor of the shoulder. It was found that these muscles had an elevated proportion of fast oxidative‐glycolytic (FOG) fibres, and lower proportions of slow oxidative (SO) and fast glycolytic (FG) fibres. This composition probably qualifies the teres major and triceps muscles to perform the sustained effort required in tunnelling excavation. The results were discussed considering published data on fibre‐type composition of mammals having different modes of life and digging behaviour. We here suggest that C. talarum has the potential of generating forces linked to rapid, powerful movements during sustained periods by means of an elevated proportion of FOG fibres, together with osteological changes that result in a great mechanical advantage of the forelimb muscles.     

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.     

Oestrogen,Progesterone and Oxytocin Receptors and COX‐2 Expression in Endometrial Biopsy Samples from the Induction of Ovulation to Luteolysis in Llamas (Lama glama)

Endometrial expression of oestrogen (ERα), progesterone (PR) and oxytocin receptor (OR) and cyclooxygenase‐2 (COX‐2) was evaluated from the induction of ovulation to luteolysis in llamas. Ovarian activity was daily assessed by ultrasonography in five females. Ovulation was induced immediately after the detection of an ovulatory follicle by a GnRH injection (Day 0). Endometrial samples were obtained by transcervical biopsies from the left and right horns on day 0 and days 4, 8, 10 and 12 post‐GnRH. Blood samples were collected daily for progesterone and estradiol‐17β determinations by RIA. An immunohistochemical technique was used to study receptors population and COX‐2 expression which were then evaluated by two independent observers. The expression of ERα and PR was highest on day 0 in the luminal epithelium and stroma in association with high plasma estradiol‐17β concentrations. Thereafter, a decrease in ERα population was registered on day 4 and a new increase of its expression was observed between days 8 and 12 in those cell types. Conversely, PR population was gradually down‐regulated until its lowest expression was reached on day 10 post‐GnRH in the luminal epithelium. Content of OR was similar throughout the study in all cell types. The expression of COX‐2 was highest from day 8 to 12 post‐GnRH in the luminal epithelium, in relation to the time of maximal PGF_2α release. Both steroid receptors populations and COX‐2 expression were similar between horns. Meanwhile, OR expression was higher in the right than in the left uterine horn. In summary, this study showed that the loss of endometrium sensitivity to progesterone by days 8–10 post‐induction of ovulation and the concomitant increase of COX‐2 expression could play a key role in the mechanism of luteolysis and somehow be related to the short corpus luteum lifespan of llamas.     

A Case of Successful Pregnancy in a Ewe with Uterus Didelphys

Uterus didelphys is a rare congenital abnormality of the reproductive tract. Although it occurs in various species, there are no published reports describing pregnancy outcome in association with this abnormality. Herein we describe a case of successful unilateral singleton pregnancy in a ewe incidentally found to have uterus didelphys during the course of a biomedical research study. The pregnancy was established using assisted reproductive techniques and interrupted in late gestation, at which point the abnormality was identified. Serial ultrasound assessment of foetal biometry revealed a normal foetal growth trajectory. Despite a 45% reduction in placentome number, total placentome weight was near normal secondary to compensatory placentome growth and development. To our knowledge, this is the first detailed report of normal foetal growth in an animal with uterus didelphys and illustrates the ability of the ovine placenta to adapt to a reduced number of placentomes and maintain foetal nutrient supply.     

Development of a stand density management diagram for even-aged pedunculate oak stands and its use in designing thinning schedules

Density management is the usual method used by silviculturiststo achieve a desired future stand condition, and one of themost effective methods of design, display and evaluation ofalternative density management regimes in even-aged stands isthe use of stand density management diagrams. In the presentstudy, we describe a method for developing thinning schedulesfor even-aged pedunculate oak (Quercus robur L.) stands in Galicia(north-western Spain), using a density management diagram. Thediagram integrates the relationships among stand density, dominantheight, quadratic mean diameter and stand volume in a singlegraph. The data used in its construction were obtained from172 sample plots located throughout Galicia. The diagram isbasically composed of two equations: the first relates the quadraticmean diameter to the stand density and dominant height; thesecond relates the stand volume to the quadratic mean diameter,stand density and dominant height. These equations were fittedsimultaneously using full information maximum likelihood. Therelative spacing index is used to characterize the growing stockand the diagram provides isolines for dominant height, numberof trees per hectare, quadratic mean diameter and stand volume.Dominant height isolines together with the site index curvesallow specification of the timing of thinnings while intermediateand final harvest volumes are calculated using the stand volumesisolines.     

Predictive relationship between polyphenol and nonfat cocoa solids content of chocolate

Chocolate is often labeled with percent cocoa solids content. It is assumed that higher cocoa solids contents are indicative of higher polyphenol concentrations, which have potential health benefits. However, cocoa solids include polyphenol-free cocoa butter and polyphenol-rich nonfat cocoa solids (NFCS). In this study the strength of the relationship between NFCS content (estimated by theobromine as a proxy) and polyphenol content was tested in chocolate samples with labeled cocoa solids contents in the range of 20-100%, grouped as dark (n = 46), milk (n = 8), and those chocolates containing inclusions such as wafers or nuts (n = 15). The relationship was calculated with regard to both total polyphenol content and individual polyphenols. In dark chocolates, NFCS is linearly related to total polyphenols (r2 = 0.73). Total polyphenol content appears to be systematically slightly higher for milk chocolates than estimated by the dark chocolate model, whereas for chocolates containing other ingredients, the estimates fall close to or slightly below the model results. This shows that extra components such as milk, wafers, or nuts might influence the measurements of both theobromine and polyphenol contents. For each of the six main polyphenols (as well as their sum), the relationship with the estimated NFCS was much lower than for total polyphenols (r2 < 0.40), but these relationships were independent of the nature of the chocolate type, indicating that they might still have some predictive capabilities.     

Persistence and molecular evolution of Mycobacterium bovis population from cattle and wildlife in Doñana National Park revealed by genotype variation

The role of wildlife in tuberculosis epidemiology is being widely studied since it can affect the effectiveness of eradication campaigns in cattle. The health problem is enhanced when it concerns also wildlife welfare and biodiversity conservation. This study was performed to understand the epidemiology of Mycobacterium bovis population affecting livestock and wild animals in the Do?ana National Park using bacteriology and molecular characterisation techniques. Tuberculosis research was performed on 1209 cattle and wild animals (artiodactyla and carnivore) collected over 6 years in the Park. One hundred and sixty-three animals were found to be infected with M. bovis, comprising 7.96% of the cattle and 20.53% of the wild animals tested. Spoligotyping revealed nine patterns, being SB1232 and SB1230 the most prevalent (77.30% and 15.34% of infected animals, respectively). MIRU-VNTR analysis of a selected panel of 92 isolates showed eight different profiles, including several spoligotypes within the same MIRU-VNTR profile. The discriminatory capacity of both techniques in this panel was similar. The results obtained by combination of both techniques corroborate that wildlife species are infected with the M. bovis strains which are more prevalent in cattle and reveal their persistence. Genotype variation between isolates strongly suggests micro-evolutionary events in the M. bovis population in the same area. This study in the Do?ana National Park exposes the risk of introduction of domestic animals into wildlife areas when there is not a warranty of disease freedom, appropriate diagnostic techniques and control measures.