Dexamethasone‐Induced Eosinopenia is Associated with Lower Progesterone Production in Cattle

Eosinophilic cells accumulate in the capillaries of the bovine Graafian follicle shortly before ovulation and in the early developing corpus luteum (CL). Suppressing the migration of these eosinophilic cells by dexamethasone allowed us to evaluate their possible function in the CL development. Brown Swiss cows (n = 10) were randomly subdivided into two groups (n = 5). Every group was used once as control group and once as experimental group with two oestrous cycles between each treatment. Eighteen hours (h) after oestrus synchronization, dexamethasone or saline was given. Ovulation was induced 24 h later with gonadotropin‐releasing hormone. Another injection of dexamethasone or saline was given 12 h later. Eosinophilic cells in the blood were counted daily until day 7 after the first dexamethasone injection. The collection of ovaries took place at days 1, 2 and 5. Gene expression, protein concentration and location of angiogenic factors, chemokines, insulin‐like growth factor 1 (IGF1) and eosinophilic cells were studied. No eosinophilic cells were found in the CL of the treatment group. Blood progesterone decreased significantly in the dexamethasone group from day 8 to 17. The protein concentration of FGF2 increased significantly in CL tissue at day 2 and VEGFA decreased. Local IGF1 gene expression in the CL was not regulated. We assume from our data that the migration of eosinophilic cells into the early CL is not an essential, but an important stimulus for angiogenesis during early CL development in cattle.     

Wildlife sinks: Quantifying the impact of illegal bird trade in street markets in Brazil

Illegal wildlife trade is a widespread activity with direct impacts on biodiversity and street markets are frequently pointed out as hotspots in the wildlife trade route. However, due to its illegal character, it is difficult to accurately estimate how many individuals and how much money are handled by traders. Precise data on the number of individuals and species involved, and the drivers behind the illegal wildlife trade are essential for fighting it. We use the example of the metropolitan area of Recife, in northeastern Brazil, a well-known route of illegal wildlife in the country, to access the extent and impact street markets may have on biodiversity. We present quantitative and qualitative information on the illegal trade of wild birds in eight street markets in the area, indicating which species are preferred and why, estimating the number of animals and the volume of money involved, and quantifying the impact that the removal of those animals may have. We observed a high and diversified species offer, biased towards adult male songbirds, with birds of 15 families and 55 species on sale. Birds are kept in poor conditions and some individuals are sold for as little as US$ 1.00. However, we projected that up to 50,000 wild birds may be sold annually in the markets surveyed, including possibly 16,800 individuals of Sporophila nigricollis (the yellow-bellied seedeater), the most frequently observed species. The activity is profitable and may deal with significant amounts of money (up to nearly US$ 630,000.00/year). The numbers involved indicate that street markets are significant wildlife sinks, with a large and frequently ignored impact that must be taken into account in the control and conservation of the biodiversity, not just in Brazil but elsewhere.     

Influence of stocking density on the behaviour of juvenile Litopenaeus vannamei (Boone, 1931)

Applied ethology can help to improve Litopenaeus vannamei aquaculture. Our purpose was to demonstrate an influence of stocking density on behaviour. The shrimp were first distributed in aquaria and observed via an ad libitum observational method to construct an ethogram of social and feeding behavioural categories. The resulting ethogram consisted of retreat, cannibalism, getting to the feeding tray, occupying the feeding tray and getting feed. We then kept shrimp in aquaria at densities of 50, 75 and 100 animals m^?2 and observed them via a behavioural sampling method using our ethogram as well as focal animal sampling of behaviours derived from the literature. These literature‐derived behaviours consisted of inactivity, feeding, crawling, exploration, burying, swimming and cleaning. We found that stocking density affects the behaviour of the shrimp. Optimal searching and feeding and a low frequency of crawling and swimming occurred at a density of 50 animals m^?2, indicating a higher potential for growth and welfare at this density.     

Technologies used in the study of sperm function in cryopreserved fish spermatozoa

Sperm cryopreservation has led to transcendental changes in the reproductive biotechnology of both mammals and fish, and is a basic tool for animal improvement. However, these protocols generate damage to cell structure and physiology, altering sperm function as a result of cryoinjuries during freezing and thawing. This review is a compilation of the techniques developed and standardised for assessing sperm function in cryopreserved fish semen. Recent studies have analysed sperm function objectively, applying cellular and molecular techniques to characterise cryodamage. The Computer Assisted Sperm Analysis system has facilitated the assessment of motility, while electron microscopy (SEM and TEM) and cryo‐microscopy have made it possible to study sperm morphology and ultra‐structure. The effects of cryodamage on nuclear DNA have also been analysed using various methods, including the comet Fluorescence in situ Hybridization test, TUNEL, Sperm Chromatin Structure Assay, specific DNA sequences using RT‐PCR and specific genes by qPCR. The latter technique is used to study the mitochondrial genome (mtDNA), together with some candidate genes which are associated with bioenergy activity and sperm motility. Other parameters assessed are mitochondrial membrane potential and ATP content using high performance liquid chromatography, nuclear magnetic resonance spectrometry and cell respiration. All this information makes it possible to establish study and assessment criteria for cryopreserved fish spermatozoa. This work focuses on the use of technologies to study of quality of fish spermatozoa during cryopreservation.     

Can spleen aspirations be safely used for the parasitological diagnosis of canine visceral leishmaniosis? A study on assymptomatic and polysymptomatic animals

The purpose of this study was to evaluate the safety of spleen aspiration as a sampling technique for the parasitological detection by culture and microscopy of Leishmania (chagasi) infantum. Two hundred and nine domiciled dogs from an endemic area for visceral leishmaniasis in Bahia State, Brazil, were studied. Most dogs (87%) were seropositive for anti-L. chagasi antibodies by ELISA. Clinical signs of disease were recorded and the animals monitored during and after spleen puncture in order to detect possible complications associated with the procedure. From a total of 257 splenic punctures in the 209 animals, only three minor events occurred, with no significant consequence for the animals and no association with risk factors. Leishmania was isolated from 149/180 (83%) seropositive dogs, and from 6/26 (23%) seronegative animals. The procedure did not cause adverse side effects or unnecessary suffering and confirmed the diagnosis in a large percentage of dogs. We conclude that spleen aspiration can be considered an effective and safe procedure for the definitive diagnosis of canine visceral leishmaniosis.     

Ingestive behavior of pastured crossbred dairy cows offered different supplement types

The aim of this study was to assess the effect of different supplements on the behavior variables of crossbred dairy cows that were in pasture that comprised two 4?×?4 Latin squares (four periods, four treatments, and four animals). Each experimental period lasted 15 days (10 days to adapt animals to treatments and 5 days for data collection). The animals were supplemented twice a day, with different forage (corn silage and cactus pear) and concentrate sources (soy mea + wheat meal + corn meal + cotton seed together and soy meal as a single constituent of the concentrate). A significant difference (p?<?0.10) was observed for the percentage of time spent consuming the supplement and for idleness, rumination, and bite rate at the time of supplementation. The supplement intake period was greater for the cactus pear-based supplements due to the lower dry matter content. Those based on corn silage resulted in longer rumination periods than those consisting of cactus pear; however, the opposite was observed for supplements based on the cactus, which showed higher percentages of time for idleness. The supplementation influenced the ingestive behavior of crossbred dairy cows.     

Tolerance of potentially diazotrophic bacteria to adverse environmental conditions and plant growth-promotion in sugarcane

Sugarcane is one of the crops responsible for the high consumption of fertilizers in Brazil. To minimize this demand a sustainable alternative is to increase the studies to evaluate the beneficial effects of the relationship between plants/microorganisms, mainly plant growth-promoting bacteria. The objectives of this study were: a) to evaluate potentially diazotrophic bacteria isolates from sugarcane in adverse environmental conditions; b) inoculate these bacteria in sugarcane to evaluate their ability in plant growth-promotion. The study was carried in the Northeast of Brazil. Bacterial genera Burkholderia sp., Pantoea sp., Stenotrophomonas sp. and Enterobacter sp. were evaluated in different culture medium and later the bacterial isolates were inoculated in sugarcane evaluating the plant growth-promotion. Stenotrophomonas sp. and Pantoea sp. were tolerant to salinity and to different sources of carbon in acid medium and too tolerated high concentrations of pesticides and produced quorum sensing molecules (QS), but did not increase the dry matter production of sugarcane. Burkholderia sp. and Enterobacter sp. were more sensitive to salinity and pest control, but were more effective in plant growth-promotion. The tolerance of the bacteria to the adverse environmental conditions interfered negatively in the ability to plant growth-promotion.