The objective was to evaluate ovarian activity reversibility in domestic queens after short-term contraceptive treatment with deslorelin acetate. Ten mature queens were used. In all queens, the estrous cycle was evaluated every 72 h by vaginal cytology (VC) and behavior assessments. When queens had VC characteristic of interestrus or diestrus, one deslorelin acetate implant (4.7 mg) was placed in the subcutaneous tissue of the interscapular region (day of insertion = Day 0). Thereafter, VC was performed every 48 h and on Day 90, implants were removed. At Day 100, estrus and ovulation were induced with 100 IU eCG (im), followed by 100 IU hCG (im), 84 h later (Day 103.5). Queens were ovariohysterectomized on Day 106. Corpora lutea (CL) were counted, oviducts were flushed, and oocytes were identified, isolated and stained to assess viability. In all queens, blood samples for plasma progesterone concentrations were collected once a week, from Days -21 to 106. After deslorelin acetate application, four queens had VC and behavior typical of estrus, and one ovulated. Furthermore, ovulation occurred in three queens that did not have VC or behavior consistent with estrus. After the initial ovarian stimulation, all females had anestrous VC during the deslorelin treatment period. Implants were readily removed. Following implant removal, all females responded to treatments to induce estrus and ovulation. There were (mean ± SEM) 13.1 ± 5.5 CL and 8.1 ± 5.5 oocytes per queen; the oocyte recovery rate was 56.8 ± 25.4% and all recovered oocytes were viable. We concluded that deslorelin acetate can be used as a reversible short-term contraceptive in domestic cats, because estrus and ovulation were successfully induced following implant removal.

A Giardíase é uma patologia rotineira na clínica médica veterinária, causada pelo protozoário Giardia spp, que atua como fonte de infecção de diversas espécies, com destaque os cães e os seres humanos, e sendo considerada uma zoonose de grande importância para a saúde pública. Cães jovens, imunossuprimidos e que frequentam lugares públicos apresentam maior incidência para a doença. A contaminação se dá pela ingestão de cistos maduros de Giardia spp, encontrados nas fezes de animais infectados, água e alimentos contaminados. A necessidade de higienização adequada do ambiente em que os cães residem, a fim de se evitar a contaminação com outros animais e entre os seres humanos, é de grande importância no controle da giardíase.

Parrots kept in zoos and private households often develop psychological and behavioural disorders. Despite knowing that such disorders have a multifactorial aetiology and that chronic stress is involved, little is known about their development mainly due to a poor understanding of the parrots’ physiology and the lack of validated methods to measure stress in these species. In birds, blood corticosterone concentrations provide information about adrenocortical activity. However, blood sampling techniques are difficult, highly invasive and inappropriate to investigate stressful situations and welfare conditions. Thus, a non-invasive method to measure steroid hormones is critically needed. Aiming to perform a physiological validation of a cortisone enzyme immunoassay (EIA) to measure glucocorticoid metabolites (GCM) in droppings of 24 Blue-fronted parrots (Amazona aestiva), two experiments were designed. During the experiments all droppings were collected at 3-h intervals. Initially, birds were sampled for 24 h (experiment 1) and one week later assigned to four different treatments (experiment 2): Control (undisturbed), Saline (0.2 mL of 0.9% NaCl IM), Dexamethasone (1 mg/kg IM) and Adrenocorticotropic hormone (ACTH; 25 IU IM). Treatments (always one week apart) were applied to all animals in a cross-over study design. A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment). Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations). Following ACTH injection, GCM concentration increased about 13.1-fold (median) at the peak (after 3–9 h), and then dropped to pre-treatment concentrations. By a successful physiological validation, we demonstrated the suitability of the cortisone EIA to non-invasively monitor increased adrenocortical activity, and thus, stress in the Blue-fronted parrot. This method opens up new perspectives for investigating the connection between behavioural disorders and stress in this bird species, and could also help in their captive management.

Understanding the effects of atomic structure modification in hematite photoanodes is essential for the rational design of high-efficiency functionalizations. Recently, it was found that interface modification with Sn/Sb segregates considerably increases hematite photocatalytic efficiency. However, the understanding of the different electronic effects of these modifications at the atomic level is still lacking. This Letter describes the segregation effects of two different dopants–Sn and Sb–on both the solid–solid (grain boundaries) and solid–liquid interfaces (surfaces) of hematite. Within an ab initio approach, we quantitatively extract the potential barrier reduction on polycrystalline interfaces due to the dopant, which causes an increase in the inter-grain electron transport. Concomitantly, the dopants' segregation on hematite surfaces results in a decrease in the oxygen vacancy formation energy. Such vacancies lead to the experimentally observed rise of the flatband potential. The comprehension of the electronic effects of dopants on both types of interfaces explains the experimental peak efficiency of interface-modified hematite with dopant segregates, also enabling the control and design of interfaces for different higher-efficiency applications.

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There are several intrafollicular agents that have the ability to interfere with the metabolism and development of the oocyte, among these we highlight the exosomes (EXO). Thus, the aim of this study was to evaluate the capacity of EXO extracted from the follicular fluid of cows kept under thermoneutral or heat stress conditions to modulate oocyte maturation in vitro. Twenty-four Holstein cows were subjected to the following treatments for 14 days: heat stress (HS; n = 12), 38°C, 60% RH, temperature-humidity index = 88; and thermo-neutral (TN; n = 12), 24°C, 60% RH, temperature-humidity index = 71. Cows had their follicles aspirated when their diameter reached 9 to 12 mm; all follicles with this diameter were aspirated. All follicular fluid aspirated from cows subjected to HS or TN was pooled forming the groups (HS and TN). The EXO were obtained by ultracentrifugation of follicular fluid (120,000 × g for 70 min at 4°C, twice) and had their presence confirmed by transmission electron microscopy. Bos indicus cumulus-oocyte complexes (COC) collected from ovaries obtained in commercial slaughterhouse, were pooled in groups of 20 COC and randomly subjected to 1 of the following treatments: Control, matured in standard medium (TCM 199, supplemented with Earle’s salts, glutamine, NaHCO3, pyruvate, FSH, and amikacin); HS-EXO, matured in standard medium added with 10 µL of a solution of follicular EXO from HS cows; and TN-EXO, matured in standard medium added with 10 µL of a solution of follicular EXO from TN cows. The procedures were repeated 4 times, always with 20 COC per treatment in each replica. After 22 h of maturation, COC were recovered and the expression of genes related to apoptosis protection (BCL2), cell viability (STAT3), cell maintenance (RPL15), oocyte competence (BMP15), oxidative stress (CPT1B), cumulus cell expansion (HAS2), cell cycle (CDCA8), and heat stress protection (HSF1) were assessed. Oocyte genes were differentially expressed according to the source of EXO. Groups were statistically analysed using ANOVA and Tukey tests. All genes, except CPT1B, showed lower expression in TN-EXO oocytes when compared with control and HS-EXO (P < 0.05). CPT1B showed a higher expression in HS-EXO oocytes (P < 0.05). The results showed that the addition of EXO from exogenous follicles can modulate the expression of oocytes genes related to cell viability and survival. The lower expression of these genes in TN-EXO suggested that the EXO obtained in TN conditions attenuate several genes related to the oocytes maturation and viability. Surprisingly, the control oocytes showed a similar gene expression pattern of the HS-EXO. In conclusion, EXO derived from follicular fluid of cows submitted to TN or HS conditions can modulate the gene expression of oocytes matured in vitro. These results open new perspectives for the use of theses EXO as a tool to increase the efficiency of in vitro oocyte maturation. Financial support from FAPESP #12/18297–7.

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