Toxoplasma gondii antibodies in exotic wild felids from Brazilian zoos.

Serum samples from 37 captive exotic felids in 12 zoos from six Brazilian states were assayed for antibodies to Toxoplasma gondii by the modified agglutination test using formalin-fixed whole tachyzoites. Titers greater than or equal to 1:20 were considered positive. Antibodies to T. gondii were found in 24 of 37 (64.9%) felids, including one European lynx (Lynx lynx), two jungle cats (Felis chaus), two servals (Leptailurus serval), two tigers (Panthera tigris), three leopards (Panthera pardus), and 14 of 27 lions (Panthera leo). This is the first serologic analysis for T. gondii infection in exotic wild felids from Brazilian zoos.     

Physical characteristics and chemical composition of Greater Rhea (Rhea americana) eggs from wild and captive populations.

1. Eggs from wild and captive populations of Greater Rhea (Rhea americana) were studied to determine their physical and chemical characteristics. 2. Significant differences were found among populations in almost all chemical parameters studied, whereas within physical parameters only shell weight (as a proportion of the entire egg) and density showed differences. 3. Eggs from wild populations had the highest protein and linolenic acid and the lowest total lipid contents, while cholesterol levels of these eggs and of those from the largest captive area were the lowest.     

Reproductive roles predict sexual dimorphism in internal and external morphology of lake whitefish,Coregonus clupeaformis

Abstract – The different reproductive roles of the sexes can predict the direction and magnitude of sexual dimorphism of external and internal morphology. Males should have enlarged structures that enhance the acquisition of mating opportunities, whereas females are predicted to have enlarged organs that are associated with the production of eggs. We tested these predictions in male and female lake whitefish, a species in which both sexes have similar overall body size and shape. After controlling for body size, male lake whitefish had significantly longer jaws and pectoral and pelvic fins, larger hearts, and more muscle than females. Sexual dimorphism in relative muscle mass may be one of the most fundamental morphological differences between males and females. Females had relatively heavier livers than males. Because the liver is important for the breakdown of fats and vitellogenesis, selection should favour an enlarged liver in females for the processing of energy and the production of large numbers of eggs.     

Evaluation of Five Most Commonly Grown Cotton Cultivars (Gossypium hirsutum L.) Under Mediterranean Conditions: Productivity and Fibre Quality

Studies were conducted in four regions of central Greece (Larisa, Karditsa, Livadia, Thiva), to evaluate the productivity and fibre properties (fibre strength and fibre length) of the five most commonly grown cotton cultivars in these regions. The experiments lasted for 6 years (1995–2000). All the characteristics tested were strongly influenced by the factors ‘year’, ‘cultivar’ and ‘region’. Significant cultivar × region, year × cultivar, region × year and cultivar × region × year interactions occurred for all the characteristics studied. The cultivar Alegria had the highest seed‐cotton and lint yield, while Aria had the lowest ones. Both cultivars gave the highest mean lint percentage but the lowest mean boll weight (MBW). Alegria had the lowest fibre strength, while Aria had the highest. The Acala‐type cultivars, Acala SJ2 and Zeta 2, had intermediate seed‐cotton and lint yield, while Vered 171 had high seed‐cotton and satisfactory lint yield. The three cultivars mentioned above had the highest MBW and very good fibre strength. Positive correlation was observed between fibre strength and length. In spite of the fact that mean fibre length was statistically the same in all cultivars, it was influenced by the factor ‘year’, as a result of different weather conditions. The year 1996 was the most unfavourable one for seed‐cotton yield and MBW, because it was characterized by lower than average air temperatures and rather dry conditions for all study sites. The factor ‘region’, a combination of different climatic conditions and cultural practices, influenced significantly all the parameters studied.     

Blastocyst Evaluation by Means of Differential Staining: a Practical Approach

Techniques for in vitro production of embryos have been developed world-wide in different species, with promising results in human and ruminants. Thousands of human IVF-babies have been born during the last 20 years and thousands of in vitro -produced calves have been born since the late 1980s. With current methods for bovine in vitro fertilization, about 30–40% of in vitro -fertilized bovine oocytes develop further to the blastocyst stage and can be used for transfer. A proper evaluation of blastocyst quality remains however, an important challenge for every researcher involved in embryology and for every clinician who wants to select the best embryos for transfer. This review attempts to summarize the different methods available for estimation of blastocyst quality with a special emphasis upon differential staining.     

Localization of extracellular matrix receptors in ICGN mice, a strain of mice with hereditary nephrotic syndrome.

Fibrotic degeneration was examined in the kidneys of ICR-derived glomerulonephritis (ICGN) mice, a novel inbred mouse line with a hereditary nephrotic syndrome of unknown etiology considered to be a good model of human idiopathic nephrotic syndrome. In the present study, we histochemically revealed changes in accumulation of extracellular matrix (ECM) components and in localization of integrins, cellular receptors for ECM, in the kidneys of ICGN mice with the progression of renal failure. Excessive accumulation of basement membrane (laminin and collagen IV) and interstitial (type III collagen) ECM components were demonstrated in the glomeruli and tubulointerstitum of ICGN mice. Marked deposition of type I collagen and tenascin was seen only in the glomeruli of ICGN mice but not in those of ICR mice as normal controls. Increased expression of integrin alpha1-, alpha2-, alpha5- and beta1-subunits in glomeruli with fibrotic degeneration and abnormal distribution of alpha6-subunit were noted in the kidneys of ICGN mice. Excessive laminin, a ligand of alpha6beta1-integrin, was demonstrated on the tubular basement membrane, but alpha6-subunit diffusely disappeared on the basal side of the tubular epithelial cells. We presumed that abnormal integrin expression in renal tubules causes epithelial cell detachment, and consequently tubular nephropathy, and results in disorder of ECM metabolism causing excessive accumulation of ECM components in the kidneys of ICGN mice.     

Dietary crude protein concentration does not affect the leucine requirement of growing dogs

The objective of the present study was to examine the interaction between graded levels of leucine and dietary crude protein. Dose–response curves were generated using four 3 × 3 Latin squares (two dogs/square). Each square represented one of two concentrations of crude protein (140 or 280 g/kg diet) and one of two combinations of three concentrations of leucine (5.0, 7.0 and 9.0 g/kg diet or 9.0, 11 and 13 g/kg diet). An additional experiment was performed by feeding crude protein at 210 g/kg diet with either 7.0 or 11 g leucine/kg diet. Weight gain, food intake, nitrogen retention, plasma albumin and plasma amino acids were measured. The requirement was determined to be the minimum leucine concentration required to maximize weight gain and nitrogen retention. For 8–14-week-old male Beagle dogs, 140 g crude protein/kg diet in a diet containing 18 kJ metabolizable energy/g does not appear to support maximal growth. The leucine requirement was not affected by doubling the dietary crude protein level from 140 to 280 g/kg diet. From these results, the leucine requirement of 8–14-week-old Beagle dogs appears to be 11 g leucine/kg diet independent of the level of dietary crude protein, whereas dogs over 14 weeks require only 7 g leucine/kg diet for maximal nitrogen retention.