Oral administration recombinant porcine epidermal growth factor enhances the jejunal digestive enzyme genes expression and activity of early-weaned piglets

This study attempted to determine ingested porcine epidermal growth factor (pEGF) on the gastrointestinal tract development of early-weaned piglets. Thirty-two piglets (14-day weaned) were randomly allotted to supplemented with 0 (control), 0.5, 1.0, or 1.5 mg pEGF/kg diet. Each treatment consisted of four replicates with two pigs per pen for a 14 days experimental period. Piglets were sacrificed and gastrointestinal tract samples were collected to measure mucosa morphology, mRNA expression and activities of digestive enzymes in the gastrointestinal tract of piglets at the end of the experiment. Diets supplemented with pEGF failed to influence growth performance but tended to increase jejunal mucosa weight (p < 0.09) and protein content (p < 0.07). Piglets supplemental pEGF induced incrementally the gastric pepsin activity (p < 0.05) and stimulated jejunal alkaline phosphatase (ALP) and lactase activities accompanied with the increase of jejunal ALP and maltase mRNA expression. No effect of pEGF on the activities of all enzymes in ileum except the stimulation of ileal aminopeptide N mRNA expression. These results reveal that dietary pEGF supplementation might enhance gene expression and activities of digestive enzymes in the stomach and jejunum of piglets.     

Distribution of Cytochrome P450-side Chain Cleavage in the Theca Interna Layers of Bovine Small Antral and Cystic Follicles

Cystic follicle is anovulatory follicular structure that is caused by an endocrine imbalance. The activity of cytochrome P450‐side chain cleavage (P450scc) is essential for the initiation of steroidogenesis in the follicle. The present study was designed to compare the frequency of cells containing P450scc between healthy and atretic small antral follicles, and among several types (I, II and III, classified based on the presence of granulosa layer) of cystic follicles. Paraffin sections of healthy (2–5 mm in diameter), atretic (2–5 mm) and cystic follicles (>25 mm) were immunohistochemically stained with rabbit polyclonal antibody to bovine P450scc. The P450scc‐positive cells were counted in four different regions of the follicles from the apical to the basal side. In small antral follicles and cystic follicles, P450scc‐positive cells were localized in the theca interna layers but not granulosa layers. The P450scc‐positive cell populations decreased in the late atretic follicles compared with the early and advanced atretic follicles at all the regions of follicle. Type III cystic follicles showed significantly lower frequencies of P450scc‐positive cells than those in the types I and II cystic follicles. These results suggest that in both small and cystic follicles in cows, total loss of granulosa cells may be associated with the reduction of frequency of P450scc‐positive cells in theca interna layer.     

Effect of dopamine on excretory urographic image quality and the prevention of contrast-induced nephropathy in dogs

The effect of low dose dopamine on the excretory urographic image quality and contrast media-induced nephropathy in normal dogs (experiment 1) and the dogs with decreased renal function (experiment 2) were assessed. In experiment 2, decreased renal function was induced by gentamicin overdose. In each experiment, animals were divided into 3 groups. In group 1, only contrast medium (iohexol) was administered. In group 2, contrast medium plus intravenous fluid (0.9% saline) were administered. And in group 3, contrast medium plus intravenous fluid and low dose dopamine were administered. Investigated parameters included intrarenal resistive index (RI), serum BUN and creatinine concentrations, contrast medium elimination time and radiographic image quality. In experiment 1, RI of group I increased at 80 min after contrast medium administration (p<0.05), but RI of group 3 decreased at 48 and 72 hr (p<0.05). Serum BUN concentration of group 1 was higher than that of group 2 and 3 (p<0.05); in radiographic examination, contrast medium elimination time decreased in group 2 and 3, but image quality of group 2 was inferior to that of group 3. In experiment 2, image quality of group 3 only provided adequate visualization of renal structures. The formula of contrast medium plus low dose dopamine was found to provide good nephrogram and pyelogram image quality without supplemental contrast medium, and to protect renal tubules from prolonged exposure to concentrated contrast medium.     

Machine vision smart sprayer for spot-application of agrochemical in wild blueberry fields

An essential part of the wild blueberry cropping system is the proper management of agrochemical inputs including herbicides, fungicides and insecticides. A machine vision system was developed and mounted on the rear sprayer boom 0.18 m in front of the sprayer nozzles capable of targeting the agrochemical application on an as-needed basis. The three-point hitch mounted sprayer featured 27 nozzles over a 13.7 m boom width and a storage tank capacity of 1135 l. Nine digital color cameras continually take images in real-time while computer software processes the images in 0.15 s to determine the target locations where the nozzles open and spray at speeds up to 1.77 m s^?1. Two wild blueberry fields in central Nova Scotia were selected for smart sprayer performance testing with spot-application (SA) of agrochemical as compared to control and uniform application techniques. Chateau^® herbicide was applied in a field with an infestation of hair cap moss. Spray droplet comparison showed moss patches were properly targeted using the smart sprayer. SA provided the same coverage performance as compared to uniform on the moss targets with herbicide application savings of 78.5% using the smart sprayer. Harvestable yield results were similar for all application tracks. TruPhos Magnesium and ZincMax foliar fertilizers were tank mixed with Bravo^® and Proline^® fungicides and applied to compare the difference of SA, control and uniform application. Results showed SA of foliar fertilizer and fungicide led to less premature leaf drop and increased the blueberry stem height, number of branches, stem diameter and fruit buds. SA of foliar fertilizer and fungicide also increased the percent of healthy wild blueberry plants by 57.8% and the harvestable yield by 137.8%. Fungicide application savings using the smart sprayer for SA were 11.6%.     

Determination of allogeneic and xenogeneic markers in the genus of Tilapia. II. Identification of T. aurea,T. vulcani and T. nilotica by electrophoretic analysis of their serum proteins

Sera from Israeli stocks of T. nilotica, T. vulcani and T. aurea were analysed, by polyacrylamide gel electrophoresis, for the existence of species-specific markers. Markers situated in the fast region of the electropherogram were found to be male sex and species specific. Interspecies polymorphism in markers in the post albumin area (transferrins) permit the distinction between these related species of Tilapia. No significant polymorphism was found in the electropherogram of T. vulcani. T. aurea presented some slight variations in the transferrin zone, and T. nilotica displayed a high polymorphism everywhere along the electropherogram. Two other species specific bands were found in the prealbumin zone; bands 1 (specific for T. aurea) and 2 (specific for T. vulcani). A selection of fish stocks of T. aurea and T. vulcani is currently done now on the basis of this electrophoretic criteria and on the ability to produce a high percentage of male hybrids. It was concluded that the stock of T. nilotica which exist in Israel do not represent the pure species of T. nilotica. The failure to obtain 100% males in all paired interspecific mating (Pruginin et al., 1975) was explained on this basis.     

Physiological investigations of a neurotoxin-producing phytoflagellate, Chattonella marina (Raphidophyceae)

The effects of temperature, salinity, light intensity and pH on the growth and morphology of Chattonella marina (Subrahmanyan) Hara & Chihara were examined. Optimal growth was observed at temperatures of 20-25°C, salinities of 20-30%o, light intensities of 60-140 μE m^?2 s^_1 and pH 7.5-8.5. Growth did not occur at temperatures below 15°C or above 30°C, and at salinities below 10%o. The morphology (shape) of the cells was strongly affected by temperature. At 20°C and 25°C, the population occurred mostly in a spindle-like form, whereas at 10°C, 90% of the cells became spherical within 10 days of inoculation and stationary phase cultures consisted entirely of spherical cells. Morphology was also markedly affected at 30°C. The number of spindle-like cells was highest at 20-30%o and was less at lower salinities. Light intensity and pH did not influence morphology markedly under the range of light intensities (20-180 μE m ^?2 s-^?1) and pH (6.5-8.5) tested.     

Effect of dietary protein level on the reproductive performance of Nile tilapia, Oreochromis niloticus (L.)

The effects of five dietary protein levels (25%, 30%, 35%, 40% and 45%) on the individual spawning frequency and the egg production of 135 tagged female Nile tilapia, Oreochromis niloticus (L.), were studied from 8 May to 19 November 1996 in outdoor concrete tanks. Virtually identical spawning patterns were found in all treatments, but there was a great deal of variation in the frequency of spawning and egg production. Overall, individual spawning frequency varied from one to 14 and individual egg production from 31 to 2828 eggs per spawning. The average number of spawnings and average number of eggs per spawning for fish receiving dietary protein levels of 25%, 30%, 35%, 40% and 45% were 8.0 ±1.6, 8.4 ± 2.2, 8.5 ± 2.7, 8.4 ± 2.5 and 9.4 ± 2.1 spawnings, and 1167 ± 305, 1082 ± 410, 1288 ± 324, 1145 ± 389 and 1328 ± 311 eggs per spawning, respectively. Fish receiving 45% dietary protein spawned more frequently than fish receiving 25% dietary protein. The total number of eggs produced per female was significantly higher for females fed 45% protein feed than females receiving 25% and 30% protein feeds. No definite trend was found in the number of eggs produced per spawning and the number of eggs produced per gram in females fed at different protein levels. Based on weekly checking, the time interval between spawnings varied from 7 to 77 days, and mean spawning intervals ranged from 15.8 to 17.1 days. Sixty per cent of females spawned after an interval 14 days, 15% after 21 days, 13.6% after 7 days, 7.2% after 28 days, 1.8% after 35 days and 1.0% after 42 days, and the time interval was 49-77 days for the rest of the females (1.5%). In all treatments, maximum spawning activity was recorded from May to August, and thereafter, it gradually decreased and no spawning females were found in November.     

Role of T-bet in commitment of TH1 cells before IL-12-dependent selection

How cytokines control differentiation of helper T (TH) cells is controversial. We show that T-bet, without apparent assistance from interleukin 12 (IL-12)/STAT4, specifies TH1 effector fate by targeting chromatin remodeling to individual interferon-gamma (IFN-gamma) alleles and by inducing IL-12 receptor beta2 expression. Subsequently, it appears that IL-12/STAT4 serves two essential functions in the development of TH1 cells: as growth signal, inducing survival and cell division; and as trans-activator, prolonging IFN-gamma synthesis through a genetic interaction with the coactivator, CREB-binding protein. These results suggest that a cytokine does not simply induce TH fate choice but instead may act as an essential secondary stimulus that mediates selective survival of a lineage.     

Cloning of bovine CD69

CD69 is rapidly inducible on various hematopoietic cells upon stimulation and is detectable as an early activation antigen. Although CD69 is well characterized in human and mouse, no information is available on bovine CD69. We report here that, bovine CD69 was cloned from a cDNA expression library prepared from activated peripheral blood lymphocytes. The full-length cDNA contained an 80bp 5' untranslated region, followed by a 600bp coding region and AU-rich motifs in a 3' untranslated region (GenBank accession number AF272828). Comparison of the bovine CD69 coding sequence reveals 69.4 and 78.2% nucleotide sequence identities with mouse and human CD69, respectively. The predicted amino acid sequence of bovine CD69 shares 56.3 and 62.3% sequence identity when compared with mouse and human CD69, respectively. Bovine CD69 has the highly conserved amino acid sequences found in the C-type lectin family, suggesting that the conserved residues may be important for conformation and binding to the, as yet unidentified ligand. In addition, the cytoplasmic tail of bovine CD69 has two casein kinase-2 (CK-2) phosphorylation sites. These data suggest that bovine CD69 plays an important role in the activation of lymphocytes.