Critical thermal maxima and minima for curimbatá, Prochilodus scrofa Steindachner, of two different sizes

Critical thermal maxima (CTMax) and minima (CTMin) were determined for Prochilodus scrofa Steindachner of two sizes (19.5 ±7.2 g and 249 ± 42.4 g). acclimated at 15. 20, 25, 30 and 35 ± 1°C. The CTMax and the CTMin for the smaller fish were 33.9. 36.7. 38.7, 40.3. 42.0°C and 5.0, 7.2. 9.2. 10.3. 13.4^oC and for the larger (Ish 33.3, 35.7, 38.2. 40.6. 42.6°C and 6.5, 8.2. 10.8. 12.4, 14.6°C. respectively, at each acclimation temperature. The CTMin from smaller fish were significantly lower than those from larger ones but the CTMax did not show any such difference. These results indicate that P. scrofa is suitable for culture in south-eastern and even in southern Brazil where winter temperatures may drop to very low levels, mainly at night. The zone of thermal tolerance calculated by CTMax and CTMin was equivalent to 1046°C² and 964.2°C², respectively, for smaller and larger fish, showing a high degree of eurythermicity.     

Protein-losing nephropathy associated with Borrelia burgdorferi seropositivity in a soft-coated wheaten terrier: Response to therapy

A soft-coated wheaten terrier was examined for lameness with subsequent identification of protein-losing nephropathy, hypoalbuminemia, hyperglobulinemia, and seroconversion to Borrelia burgdorferi. Following doxycycline therapy, the urine protein loss decreased significantly and serum albumin concentration remained close to or within the reference interval for over 3 years, contrary to the reported poor prognosis for renal disease associated with B. burgdorferi or protein-losing nephropathy of soft-coated wheaten terriers.     

Paraoxonase (PON) 1, 2 and 3 Expression in Granulosa Cells and PON1 Activity in Follicular Fluid of Dairy Cows

Normal metabolic activity in ovarian follicles may result in oxidative stress and damage to oocytes. The aim of this study was to evaluate expression of the natural anti‐oxidants paraoxonase (PON) 1, 2 and 3 in granulosa cells and PON1 activity in follicular fluid (FF) and plasma of dairy cows. For the first experiment, ovaries were collected from cows at slaughter, after which follicles were dissected and classified as oestrogen active (EAF) or atretic (ATF). Expression of PON1, PON2 and PON3 mRNA was evaluated in granulosa cells, and activity of PON1 was measured in FF. PON1 mRNA was undetectable in granulosa cells, PON2 mRNA expression was not different between follicle types, and PON3 mRNA tended to be higher in EAF (p = 0.11). The activity of PON1 in FF was higher (p = 0.01) for EAF (82.6 ± 8.0 kU/L) than ATF (53.9 ± 6.8 kU/L), as were high‐density lipoproteins (HDL), low‐density lipoproteins (LDL) and total cholesterol concentrations. In the second experiment, we aimed to compare plasma and FF PON1 activity in early lactation Holstein cows (n = 15) with pre‐ovulatory EAF. Activity of PON1 was twofold higher (p < 0.0001) in plasma (122.5 ± 11.1 kU/L) than in FF (61.4 ± 5.2 kU/L). Plasma concentrations were also higher (p < 0.0001) for HDL, LDL and total cholesterol when compared to FF. In conclusion, FF concentrations of PON1, HDL, LDL and total cholesterol were higher in healthy oestrogen active bovine follicles than in atretic follicles. PON1 was not expressed by granulosa cells indicating that high PON1 activity in bovine FF is apparently derived by transfer from blood in association with HDL.     

Effect of Recombinant Bovine Somatotropin on Plasma Concentrations of Insulin‐like Growth Factor I,Insulin and Membrane Integrity of Bull Spermatozoa

This study aimed to evaluate the effect of the exogenous recombinant bovine somatotropin (rbST) on plasma concentrations of insulin‐like growth factor I (IGF‐I), insulin and semen quality of bulls. Twenty bulls (Aberdeen Angus and Brangus) were divided by breed into two groups. Placebo group was injected with NaCl 0.9% (s.c.) and treatment group with rbST (s.c., 500 mg) at days 0 and 14 of the experiment. Immediately after semen collection, blood samples were taken on days 0, 14, 28, 42 and 56 of the experiment. Semen was also collected on day 70 of the experiment. Evaluation of sperm motility was performed at pre‐freezing and post‐thawing stage, whereas assessment of sperm membrane integrity was performed after freezing and thawing. Analysis of data revealed that the effect of treatment and treatment‐by‐collection day on plasma concentrations of IGF‐I and insulin was not significant. However, mean plasma concentrations of IGF‐I and insulin were affected (p < 0.0001) by days of blood sampling. Effect of treatment and treatment‐by‐collection day on motility of spermatozoa was similar (p > 0.05) at pre‐freezing and post‐thawing stage. Intactness of plasmalemma and tail membrane of spermatozoa at post‐thawing stage was higher (p < 0.05) in rbST‐treated group than in control. In conclusion, rbST did not affect plasma concentrations of IGF‐I and insulin, however, it did improve post‐thaw sperm membrane integrity.     

A potential krimpsiekte vaccine

Krimpsiekte, a chronic form of cardiac glycoside poisoning, is an important plant-induced intoxication of small stock in South Africa. It is caused by cumulative, neurotoxic bufadienolides, such as cotyledoside. A cotyledoside-bovine serum albumin conjugate was synthesized to immunize animals. The efficacy of the cotyledoside-conjugate in inducing an immunological response was ascertained in rabbits (n = 4) and sheep (n = 4) by determining cotyledoside antibody titres with an ELISA using cotyledoside-hen ovalbumin as antigen. The formation of anticotyledoside antibodies was induced in both rabbits and sheep following immunization with the cotyledoside-protein conjugate. Protection provided by the vaccine was demonstrated by challenging sheep (n = 4) with repeated, daily doses of cotyledoside (0.015 mg/kg) administered intravenously, commencing 45 days after the initial vaccination. One control animal died on Day 3 of the challenge period and the other was severely affected after administration of the third cotyledoside dose. The immunized ewes (n = 2) remained clinically unaffected and the challenge was suspended following six daily injections. Vaccination as a means of preventing krimpsiekte seems to be quite feasible and deserves further investigation.     

Investigation to determine digestibility coefficients of various raw materials in diets for gilthead sea bream, Sparus auratus L.

A number of raw materials were tested to obtain the in vivo apparent digestibility coefficients of protein, lipid and gross energy for gilthead bream. Sparus auratus L., under controlled conditions. In the case of protein digestibility assessment, a standard in vitro method was also included for comparison. Protein digestibility coefficients were generally high, with values between 60% and 96% being observed for most of the materials studied. However, some exceptions were apparent in materials of both animal and plant origin. Lipid digestibilities also ranged between 50% and 90%. Values for energy digestibilities indicated a much greater variation, from 6% to 80%. These observations are discussed in relation to the nature and source of ingredients and to the type of processing technology employed.     

Acrylamide formation mechanism in heated foods

Recent findings of a potential human carcinogen, acrylamide, in foods have focused research on the possible mechanisms of formation. We present a mechanism for the formation of acrylamide from the reaction of the amino acid asparagine and a carbonyl-containing compound at typical cooking temperatures. The mechanism involves formation of a Schiff base followed by decarboxylation and elimination of either ammonia or a substituted imine under heat to yield acrylamide. Isotope substitution studies and mass spectrometric analysis of heated model systems confirm the presence of key reaction intermediates. Further confirmation of this mechanism is accomplished through selective removal of asparagine with asparaginase that results in a reduced level of acrylamide in a selected heated food.     

Morphological and Nutritional Properties of Birdsfoot Trefoil (<Emphasis Type="Italic">Lotus corniculatus</Emphasis> L.) Autochthonous Populations in Serbia and Bosnia and Herzegovina

Birdsfoot trefoil (Lotus corniculatus L.) is a highly variable and widely distributed Old World perennial forage legume found in wild and naturalized populations throughout temperate regions of Europe, Asia Minor, North Africa, North and South America, Australia, and New Zealand. Understanding the relationships among birdsfoot trefoil morphological, ecogeographic and chemical characteristics may provide insights for better utilizing of exotic germplasms. Ten birdsfoot trefoil populations were and sampled and determined in Serbia and Bosnia and Herzegovina. Some morphological properties, such as growth form of populations, flower color, flowering period, number of stems, length of main stem, number of racemes per stem, number of flowers per inflorescence, number of pods per racemes, number of seeds per pods, hard seeds in the first year, dry matter (DM) yield, and some chemical properties, such as content of crude protein, ash, fat, crude fiber, phosphorus, calcium, magnesium, potassium, K/(Ca+Mg) ratio, and sulfur, manganese, iron, copper, zinc, selenium and tannin contents, were determined in all populations. Serbia is an important origin center of genes for many legume species. Considering the high values of their traits, some Serbian trefoil populations could serve as a valuable breeding material. In comparison with populations from other parts of the world, Serbian populations are superior in chemical properties and nutritional quality values. The investigated populations clustered in two distinct groups according to the analyzed characteristics.