Indices for physiological assessment of nutritional condition in pregnant collared peccaries (Tayassu tajacu)

Hematological and serum biochemical responses to two levels of dietary energy (high energy [HE], 3300 kcal digestible energy [DE]/kg; moderate energy [ME], 2300 kcal DE/kg) and protein (high protein [HP], 16.0% crude protein; moderate protein [MP], 8.4% crude protein) during gestation in 15 collared peccaries (Tayassu tajacu) were examined. Dietary energy and protein levels influenced body weight gain during gestation. Red blood cell counts and lymphocyte concentrations were higher and neutrophil concentrations were lower among females fed an HP diet compared to those fed an MP diet. Alkaline phosphatase and alpha-2 globulin concentrations were higher among females fed an MP diet. Aspartate aminotransferase and cholesterol concentrations were higher and calcium and thyroxine concentrations were lower among females fed ME diets compared to those fed HE diets. These results suggest that physiological indices used in combination with morphological measurements can be useful in assessing collared peccary nutritional health during gestation.     

Penile paralysis and paraphimosis associated with reserpine administration in a stallion

Reserpine was administered to an 8-yr-old Thoroughbred stallion at a dosage of 5 mg subcutaneously (s.c.) every 2 wk for a 2-mo period to control unmanageable behavior. Reserpine produced a satisfactory calming effect that lasted for about 2 wk. After the last injection, the stallion developed penile paralysis and was unable to retract his penis, resulting in paraphimosis and attendant penile edema. The prolapsed penis was reduced and kept within the prepuce by placing a purse string suture in the preputial orifice. Phenylbutazone was given orally (1 gm) and the stallion was exercised for 20 to 30 min twice daily. This treatment was continued for 20 d with little improvement. The purse string retention suture cut through the skin 5 d after the stallion was discharged from the clinic. The penis was then supported against the abdominal wall and the stallion was exercised by hand for 30 min each day. The stallion was not used for breeding within 34 mo after the last injection of reserpine. A breeding soundness examination was performed approximately 3 yr after the initial injury. At this time the stallion's penis was noted to extend 5 to 8 cm from the prepuce when in a detumescent state. Although the stallion protruded his penis when exposed to a mare in estrus, a full rigid erection was never attained. Examination of the penis revealed partial engorgement of the corpus cavernosum penis and a 2.5-cm-wide dorsal semi-circumferential depression of the penile shaft approximately 10 to 12 cm proximal to the glans penis. The penile shaft and glans penis distal to this depression were cooler than the proximal portion of the penis. Semen collection was attempted, aided by manual insertion of the penis into the artificial vagina. When serving the artificial vagina, no "belling" of the glans penis was observed, although ejaculation occurred. Semen evaluation indicated normal spermatozoal motility and morphology parameters. The stallion was able to breed several mares with manual assistance to guide the penis into the vagina and one mare was diagnosed pregnant.     

Histochemical localization of cysteine-rich proteins by tissue printing on nitrocellulose

A rapid technique for the histochemical localization of cysteine-rich proteins in plant tissues was developed. It is based on the immediate transfer of proteins to nitrocellulose membranes when a fresh cut organ is pressed against the membrane surface. The print was labeled for cysteine-rich proteins by reduction and alkylation of cysteinyl residues with dansylated iodoacetamide [N-iodoacetyl-N'-(-5-sulfo-1-naphthyl)ethylenediamine]. The S-carboxymethylated proteins were visualized by their fluorescence when excited with 360 nm light.     

Long-term effects of ungulates on phytophagous insects

Abstract.  1. Most plants interact with a diverse suite of herbivores, allowing the opportunity for the existence of positive and negative interactions between highly dissimilar organisms. However, most studies on herbivorous interactions have been performed under the assumption that they occur mainly between similar species. Consequently, ecologists are still far from a full understanding of the ecological factors that determine insect population dynamics.
2. In this study, a 7-year field experiment was conducted that manipulated the presence of ungulates to evaluate their effects on the abundance, attack rate, and survival of four guilds of co-occurring herbivorous insects living on the same host plant: seed predators, stem borers, gall makers and sap suckers. These four guilds differed in habits and behaviour, the first three being sessile and endophytic and the last being free-living.
3. This study shows that the abundance of all four guilds was negatively affected by ungulates. However, the effect on attack rate differed among guilds, as mammals do not affect the seed predator attack rate. Ungulates also differentially affected insect survival, ingesting only seed predators and gall makers.
4. In summary, this study suggests that diverse mechanisms may affect different insect guilds in different ways. Therefore, competition between disparate herbivores appears to be complex and can be provoked by multiple mechanisms.     

Antisense RNA decreases AP33 gene expression and cytoadherence by <Emphasis Type="Italic">T. vaginalis</Emphasis>

Background  

Host parasitism by Trichomonas vaginalis is complex. Adherence to vaginal epithelial cells (VECs) is mediated by surface proteins. We showed before that antisense down-regulation of expression of adhesin AP65 decreased amounts of protein, which lowered levels of T. vaginalis adherence to VECs. We now perform antisense down-regulation of expression of the ap33 gene to evaluate and confirm a role for AP33 in adherence by T. vaginalis. We also used an established transfection system for heterologous expression of AP33 in T. foetus as an additional confirmatory approach.     

Dexamethasone downregulates expression of several genes encoding orphan nuclear receptors that are important to steroidogenesis in stallion testes

Glucocorticoids impair testosterone synthesis by an unknown mechanism. Stallions treated with the synthetic glucocorticoid dexamethasone had testes collected at 6 or 12 hours postinjection. The testicular expression of selected genes encoding nuclear receptors and steroidogenic enzymes was measured. At 6 hours, dexamethasone treatment decreased levels of NR0B2, NR4A1, NR5A1, and NR5A2 messenger RNAs (mRNAs) and NR5A2 mRNA levels remained depressed at 12 hours. In contrast, dexamethasone increased levels of NFKBIA mRNA at both time points. At 6 hours, dexamethasone did not alter levels of NR0B1, NR2F1, NR2F2, NR3C1, CYP11A1, CYP17A1, CYP19A1, DHCR24, GSTA3, HSD3B2, HSD17B3, LHCGR, or STAR mRNAs. In primary cultures of Leydig cells, 10 ^?9 and 10 ^?7M dexamethasone decreased levels of NR4A1 and NR5A1 mRNAs and increased those of NFKBIA mRNA. Our discovery that dexamethasone downregulates NR4A1, NR5A1, and NR5A2 genes, known to be important for testicular functions, may be part of the mechanism by which glucocorticoids acutely decreases testosterone.     

Molecular dynamics simulations of human tRNA Lys,3 UUU: the role of modified bases in mRNA recognition

Accuracy in translation of the genetic code into proteins depends upon correct tRNA-mRNA recognition in the context of the ribosome. In human tRNA(Lys,3)UUU three modified bases are present in the anticodon stem-loop--2-methylthio-N6-threonylcarbamoyladenosine at position 37 (ms2t6A37), 5-methoxycarbonylmethyl-2-thiouridine at position 34 (mcm5s2U34) and pseudouridine (psi) at position 39--two of which, ms2t6A37 and mcm5s2U34, are required to achieve wild-type binding activity of wild-type human tRNA(Lys,3)UUU [C. Yarian, M. Marszalek, E. Sochacka, A. Malkiewicz, R. Guenther, A. Miskiewicz and P. F. Agris (2000) Biochemistry, 39, 13390-13395]. Molecular dynamics simulations of nine tRNA anticodon stem-loops with different combinations of nonstandard bases were performed. The wild-type simulation exhibited a canonical anticodon stair-stepped conformation. The ms2t6 modification at position 37 is required for maintenance of this structure and reduces solvent accessibility of U36. Ms2t6A37 generally hydrogen bonds across the loop and may prevent U36 from rotating into solution. A water molecule does coordinate to psi39 most of the simulation time but weakly, as most of the residence lifetimes are <40 ps.     

Morphometric analysis and taxonomic revision of the Vriesea paraibica complex (Bromeliaceae)

The species related to Vriesea paraibica (Bromeliaceae, Tillandsioideae) have controversial taxonomic limits. For several decades, this group has been identified in herbarium collections as V. × morreniana, an artificial hybrid that does not grow in natural habitats. The aim of this study was to assess the morphological variation in the V. paraibica complex through morphometric analyses of natural populations. Two sets of analyses were performed: the first involved six natural populations (G1) and the second was carried out on taxa that emerged from the first analysis, but using material from herbarium collections (G2). Univariate ANOVA was used, as well as discriminant analysis of 16 morphometric variables in G1 and 18 in G2. The results of the analyses of the two groups were similar and led to the selection of diagnostic traits of four species. Lengths of the lower and median floral bracts were significant for the separation of red and yellow floral bracts. Vriesea paraibica and V. interrogatoria have red bracts; these two species are differentiated by the widths of the lower and median portions of the inflorescence and by scape length. These structures are larger in the former and smaller in the latter. Of the species with yellow floral bracts, V. eltoniana is distinguished by longer leaf blades and scapes and V. flava is characterized by its shorter sepal lengths. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 163–181.