Historical Pollution of an Urban Watershed Based in Geochemical, Geoacumulation, and EROD Activity in PLHC-1 Analyses in Sediment Cores.

In the present study, the environmental changes over the past 100 years in the Cambé River watershed in Southern Brazil were investigated. For this, a sediment core was collected to examine the distribution of metals, polycyclic aromatic hydrocarbons (PAHs), and ecotoxicological markers. The core corresponds from 1914 to 2012, which was obtained by the decay of 210Pb. Changes in the study area also were examined by: Geoaccumulation index (Igeo) and enrichment factor (EF), sediment quality guidelines (SGQs), and ethoxyresorufin-O-deethylase (EROD) activity in Poeciliopsis lucida hepatocellular carcinoma (PLHC-1) cells line. The Σ16 PAHs ranged from 242.6 to 40,775 ng g-1, with pyrogenic source at the beginning of the core, which likely corresponds to the burning of forests to establish the city and the later use of fossil fuels from 1960 to 2012. In the 1930s, most of metals presented a concentration below the background. After the 1930s, high concentrations can be associated with the intense use of fertilizers (Cd, Cu, Zn, Hg) and increases in urban traffic (Zn and Pb). Igeo showed that the distribution of Cu is considered moderately to strongly polluted, and the EF of Pb was considered as moderately polluted. Statistical analyses showed a strong relation between the presence of the ANP, FLU, PHE, BaP, IND, and Bghi compounds and the induction of EROD activity, and no correlation with heavy metals. A prediction model for the linear regression was obtained between the ANP and BaP concentrations and the EROD activity, with an accuracy of 99%.

Profile of LH release in response to intramuscular treatment with kisspeptin in Bos indicus and Bos taurus prepubertal heifers.

The main objective of this study was to evaluate the effect of intramuscular (I.M.) administration of different doses of kisspeptin (Kp) on the pattern of luteinizing hormone (LH) release in Bos taurus and Bos indicus prepubertal heifers. Holstein heifers weighing 215.1 ±â€¯38.6 kg (n = 24; aged 5-8 mo) and Gyr heifers weighing 215.4 ±â€¯31.4 kg (n = 24; aged 6-10 mo) were enrolled in this study. The animals were confirmed as non-cyclical by absence of a corpus luteum (CL) as determined by ultrasound scanning of the ovaries and low circulating P4 concentrations (<1.0 ng/mL) evaluated at a 10-day interval (on day -10 and day 0). For each genetic group, heifers were randomly assigned to one of four treatments: Kp at 2.5 µg/kg body weight (Kp2.5), Kp at 5.0 µg/kg (Kp5), Kp at 10 µg/kg (Kp10), or gonadotropin-releasing hormone (GnRH) agonist (0.01 mg of buserelin acetate per heifer), all administered by I.M. injection. All animals responded to the treatments with an LH surge (P < 0.01). There was an effect of breed (P < 0.01) on induced LH release, with Holstein heifers having a greater area under the curve for LH (AUC; P < 0.01) and greater LH peak amplitude (P < 0.01) than Gyr heifers. Nevertheless, greater AUC for LH occurred in Kp10 heifers for both breeds. There was no effect of breed on LH AUC or LH peak amplitude after GnRH agonist treatment. For both breeds, heifers treated with Kp displayed an earlier (P < 0.01) LH peak with a reduced amplitude of the LH peak (P < 0.01) and reduced LH AUC (P < 0.01) compared to heifers treated with GnRH agonist. Thus, both zebu and taurus immature heifers treated with I.M. Kp injection responded with a rapid and dose-dependent LH surge, although even large doses of the native Kp-10 did not mimic the magnitude or duration of the LH surge produced by the GnRH agonist. The early onset of the LH surge after Kp treatment and the short duration suggest that the effects of Kp were likely due to pituitary rather than hypothalamic action. Finally, there seems to be a greater responsiveness to Kp in Bos taurus than in Bos indicus prepubertal heifers, although LH release after GnRH agonist treatment was similar for the two breeds.

Action time and feed frequency of Lactobacillus plantarum for Nile tilapia / Tempo de ação e frequência alimentar do Lactobacillus plantarum para tilápia-do-nilo

O objetivo desta pesquisa foi avaliar o tempo de ação do Lactobacillus plantarum no trato intestinal, assim como em qual frequência esse probiótico deve ser oferecido para tilápia-do-nilo (Oreochomis niloticus). Quarenta e oito tilápias foram alimentadas com ou sem probiótico, durante 14 dias. Após esse período, os peixes foram esviscerados, e amostras do trato intestinal foram semeadas em ágar TCBS, cetrimide e MRS. Esse procedimento foi repetido dois, quatro e seis dias após o 14º dia. Depois disso, 252 tilápias foram divididas em quatro tratamentos, peixes alimentados com probiótico suplementado em 100%, 50%, 25% e 0% (controle) das alimentações. Após nove semanas, os índices zootécnicos foram avaliados. No dia zero, verificou-se maior concentração de bactérias ácido-lácticas e menor concentração de Vibrios spp. e de Pseudomonas spp. no trato intestinal dos alevinos alimentados com probiótico. Peixes alimentados com 100% e 50% das alimentações suplementadas com probiótico apresentaram melhores índices zootécnicos que os peixes alimentados com 25% de suplementação e sem suplementação. O L. plantarum atuou por quatro dias após a última alimentação, e, para obter os melhores índices, essa cepa deve ser suplementada em 50% das alimentações por dia para tilápia-do-nilo (O. niloticus).(AU)

Retention systems for extraoral maxillofacial prosthetic implants: a critical review.

We describe the techniques available for retention of implant-supported prostheses: bar-clips, O-rings, and magnets. We present reported preferences and, although this is limited by the heterogeneity of methods used and patients studied, we hope we have identified the best retention systems for maxillofacial prosthetic implants. If practitioners know the advantages and disadvantages of each system, they can choose the most natural and comfortable prosthesis. We searched the PubMed and Scopus databases, and restricted our search to papers published 2001-13. MeSH terms used were Maxillofacial prosthesis and Craniofacial prosthesis OR Craniofacial prostheses. We found a total of 2630 papers, and after duplicates had been removed we analysed the rest and found 25 papers for review. Of these, 12 were excluded because they were case reports or non-systematic reviews. Of the remaining 13, 10 described group analyses and seemed appropriate to find practitioner's choices, as cited in the abstract (n=1611 prostheses). Three papers did not mention the type of prosthetic connection used, so were excluded. The most popular choices for different conditions were analysed, though the sites and retention systems were not specified in all 10 papers. The bar-clip system was the most used in auricular (6/10 papers) and nasal prostheses (4/10). For the orbital region, 6/10 favoured magnets. Non-osseointegrated mechanical or adhesive retention techniques are the least expensive and have no contraindications. When osseointegrated implants are possible, each facial region has a favoured system. The choice of system is influenced by two factors: standard practice and the abilities of the maxillofacial surgeon and maxillofacial prosthetist.

Beef donor cows with high number of retrieved COC produce more in vitro embryos compared with cows with low number of COC after repeated ovum pick-up sessions.

The aim of the present study was to evaluate whether repeated ovum pick-up (OPU) procedures may affect the efficiency of OPU programs for in vitro embryo production (IVEP) in Bos indicus (Nelore) donors. In addition, the repeatability (r) efficiency of IVEP was also assessed. Data available were from 432 OPU-IVEP sessions that were performed at random stages of the estrous cycle in 36 cycling, nonlactating Nelore donors. Semen from three Nelore bulls was used for the IVF. Donors were submitted to 12 consecutive OPU procedures, with an interval of approximately 30 days between sessions. Data were analyzed as repeated measures using the GLIMMIX procedure of SAS 9.3. Cows yielding ≥15 COCs were defined as "high" COCs and cows with less than 15 COCs were defined as "low" COCs donors. The number of COCs retrieved decreased over time in donors classified with high COCs and remained fairly steady in cows with low COCs at the beginning of the program (Psession*COC retrieved groups = 0.02). Moreover, the number of COCs retrieved (P < 0.0001), and number of blastocysts produced per OPU (P = 0.001) was greater for the high COCs donors compared with the low COCs category, and these results were consistent across OPU sessions. Interestingly, there was no effect of COCs category on the rate of blastocyst development (P = 0.83). In addition, number of blastocysts produced were not affected by repeated OPU (P = 0.37) and interactions between time and COC category (P = 0.72). Similarly, blastocyst rate was not affected by repeated OPU (P = 0.21) and interactions between time and COC category (P = 0.58). Despite of COC category of the donor cows, repeatability was high for the number of COCs retrieved (r = 0.81), number of blastocysts produced per OPU (r = 0.79), and blastocyst rate (0.69). In conclusion, overall numbers of COCs decreased over time in donors classified as having high COCs. However, cumulative amounts of produced blastocysts were greater in donors with high COCs. More importantly, high repeatability was observed in terms of IVEP efficiency. Therefore, IVEP programs can be significantly improved with more aggressive selection toward donors with greater numbers of COCs.

Associations of insulin resistance later in lactation on fertility of dairy cows.

The challenge of getting dairy cows pregnant during early lactation is a well-described, worldwide problem. However, specifically in farms with poor reproductive, nutritional, and environmental conditions/management, a low pregnancy rate during early lactation is followed inevitably by an increased number of nonpregnant cows after 150 days in milk, with even more difficulties to achieve pregnancy. Therefore, several studies were designed to understand and develop strategies to mitigate reduced fertility of cows during late lactation. Experiments were performed under tropical regions to determine metabolic status during lactation and association of stage of lactation on oocyte quality and fertility. Lactating cows with extended days not pregnant (e.g.,>150 days in milk) often had systemic metabolic alterations, including development of peripheral insulin resistance and various oocyte alterations, including reduced expression of genes encoding glucose transport proteins, reduced amounts of mtDNA, increased expression of mitochondria-related genes, and increased expression of apoptosis-related genes. Additionally, in vitro embryo production and pregnancy per AI were lower in late- versus early-lactation cows in some but not all studies. Notwithstanding, when a normal embryo was transferred to a cow in late lactation, the pregnancy per transfer was reasonable, reinforcing the assertion that fertility problems in late-lactation cows may be associated with oocyte quality, fertilization, and/or failure of early embryo development. In conclusion, insulin resistance may reduce oocyte competence and consequently fertility in late-lactation dairy cows.

Ovarian follicular growth suppression by long-term treatment with a GnRH agonist and impact on small follicle number, oocyte yield, and in vitro embryo production in Zebu beef cows.

The aim of the present study was to evaluate small follicle number, oocyte yield, and in vitro embryo production (IVEP) in Zebu beef cows treated long term with a GnRH agonist to suppress ovarian follicular growth. Nelore (Bos indicus) cows (n = 20) showing regular estrous cycles were randomly assigned to one of two groups: control (n = 10, placebo ear implant without a GnRH agonist); GnRH agonist (n = 10, GnRH agonist ear implant containing 9.4-mg deslorelin). All cows underwent an ovum pick-up (OPU) session 14 days (Day 14) before the start of treatments (Day 0) followed by seven OPU-IVEP procedures at 30-day intervals (Days 0, 30, 60, 90, 120, 150, and 180). Semen from a single batch of a previously tested bull was used for all the IVEP. Cows treated with agonist reported a decrease over time in the proportion of animals with a (CL; P ≤ 0.05) and large follicles (>10 mm, P ≤ 0.05). These cows had a lesser number of medium + large follicles (>5 mm; 1.74 ± 0.5 vs. 4.13 ± 0.5; P ≤ 0.05), greater number of small follicles (2-5 mm; 44.3 ± 2.8 vs. 30.8 ± 1.8; P ≤ 0.05), greater yield of cumulus-oocyte complexes (COCs; 21.0 ± 2.3 vs. 15.6 ± 1.9; P ≤ 0.05), greater proportion of COCs cultured (79.2 vs. 73.9%; P ≤ 0.05), COCs cleaved (10.6 ± 1.5 vs. 6.8 ± 1.1, P ≤ 0.05), and cleaved rate (52.8 vs. 44.3%; P ≤ 0.05) compared with control cows. The number (3.4 ± 0.7 vs. 3.0 ± 0.6; P > 0.05) and proportion (16.5 vs. 19.1%; P > 0.05) of blastocysts produced were similar between agonist and control cows, respectively. The study has shown that Zebu beef cows treated long term with a GnRH agonist had follicular growth restricted to small follicles. This did not compromise the ability of oocytes to undergo IVF and embryonic development.

Short communication: Field fertility in Holstein bulls: Can type of breeding strategy (artificial insemination following estrus versus timed artificial insemination) alter service sire fertility?

The aim of this study was to compare pregnancy per artificial insemination (P/AI) from service sires used on artificial insemination after estrus detection (EAI) or timed artificial insemination (TAI) breedings. Confirmed artificial insemination outcome records from 3 national data centers were merged and used as a data source. Criteria edits were herd's overall P/AI within 20 and 60%, a minimum of 30 breedings reported per herd-year, service sires that were used in at least 10 different herds with no more than 40% of the breedings performed in a single herd, breeding records from lactating Holstein cows receiving their first to fifth postpartum breedings occurring within 45 to 375 d in milk, and cows with 1 to 5 lactations producing a minimum of 6,804 kg. Initially 1,142,859 breeding records were available for analysis. After editing, a subset of the data (n=857,539) was used to classify breeding codes into either EAI or TAI based on weekly insemination profile in each individual herd. The procedure HPMIXED of SAS was used and took into account effects of state, farm, cow identification, breeding month, year, parity, days in milk at breeding, and service sire. This model was used independently for the 2 types osires f breeding codes (EAI vs. TAI), and service sire P/AI rankings within each breeding code were performed for sires with >700 breedings (94 sires) and for with >1,000 breedings (n=56 sires) following both EAI and TAI. Correlation for service sire fertility rankings following EAI and TAI was performed with the PROC CORR of SAS. Service sire P/AI rankings produced with EAI and TAI were 0.81 (for sires with >700 breedings) and 0.84 (for sires with >1,000 breedings). In addition, important changes occurred in service sire P/AI ranking to EAI and TAI for sires with less than 10,000 recorded artificial inseminations. In conclusion, the type of breeding strategy (EAI or TAI) was associated with some changes in service sire P/AI ranking, but ranking changes declined as number of breedings per service sire increased. Future randomized studies need to explore whether changes in P/AI ranking to EAI versus TAI are due to specific semen characteristics.

Efficacy of a single intramuscular injection of porcine FSH in hyaluronan prior to ovum pick-up in Holstein cattle.

Plasma FSH profiles, in vitro embryo production (IVP) after ovum pickup (OPU), and establishment of pregnancy with IVP embryos were compared in untreated Holstein oocyte donors and those superstimulated with multiple injections or a single intramuscular (IM) injection of porcine FSH (pFSH) in hyaluronan (HA). Plasma FSH profiles were determined in 23 heifers randomly allocated to one of four groups. Controls received no treatment, whereas the F200 group received 200 mg of pFSH in four doses, 12 hours apart. The F200HA and F300HA groups received 200- or 300-mg pFSH in 5 mL or 7.5 mL, respectively of a 0.5% HA solution by a single IM injection. Plasma FSH levels were determined before the first pFSH treatment and every 6 hours over 96 hours. All data were analyzed by orthogonal contrasts. Circulating FSH area under curve (AUC) in pFSH-treated animals was greater than that in the control group (P = 0.02). Although the AUC did not differ among FSH-treated groups (P = 0.56), the total period with elevated plasma FSH was greater in the F200 group than in the HA groups (P < 0.0001). However, the F300HA group had a greater AUC than the F200HA group (P = 0.006), with a similar total period with elevated plasma FSH (P = 0.17). The IVP was performed in 90 nonlactating Holstein cows randomly allocated to one of the four treatment groups as in the first experiment. A greater proportion of medium-sized (6-10 mm) follicles was observed in cows receiving pFSH, regardless of the treatment group (P < 0.0001). Also, numbers of follicles (P = 0.01), cumulus-oocyte complexes (COCs) retrieved (P = 0.01) and matured (P = 0.02), cleavage rates (P = 0.002), and blastocysts produced per OPU session (P = 0.06) were greater in cows receiving pFSH, regardless of the treatment group. Cows in the F200HA group had a greater recovery rate (P = 0.009), number of COCs cultured (P = 0.04), and blastocysts produced per OPU session (P = 0.06) than cows in the F300HA group. Similar pregnancy rates were observed 50 to 60 days after transferring IVP embryos from donors in the different treatment groups (P > 0.05). In conclusion, a single IM injection of pFSH combined in 0.5% HA resulted in similar plasma FSH profiles as twice-daily pFSH treatments. Treatment of nonlactating donors with pFSH, with or without HA, resulted in increased IVP over untreated controls. A single dose of 200 mg of pFSH in 0.5% HA resulted in greater IVP than 300-mg pFSH in HA. Finally, pregnancy rates with IVP embryos were similar, regardless donor treatment.

Plasma anti-Müllerian hormone as a predictive endocrine marker to select Bos taurus (Holstein) and Bos indicus (Nelore) calves for in vitro embryo production.

This study evaluated the association between plasma anti-Müllerian hormone (AMH) concentrations and in vitro embryo production in Bos indicus (Nelore; experiment 1) and Bos taurus (Holstein; experiment 2) calves superstimulated or not with 140 mg of porcine follicle-stimulating hormone (pFSH; 4 decreasing doses twice daily). Oocytes were recovered from calves aged 2 to 4 mo after receiving gonadotropin stimulation (Nelore, n = 15; Holstein, n = 12) or not (Nelore, n = 15; Holstein, n = 12). Cycling heifers formed a positive control group (n = 15 for Nelore [aged 18-24 mo], n = 10 for Holstein [aged 14-16 mo]). All the calves underwent laparoscopic ovum pickup, and cycling heifers underwent a regular transvaginal ultrasound-guided ovum pickup for oocyte recovery. Immediately before oocyte retrieval, blood samples were taken for subsequent AMH determination (ng/mL). Regardless of the genetic group, calves that received pFSH (3.6 ± 1.1 in Nelore and 4.6 ± 1.2 in Holstein) or did not receive pFSH (3.2 ± 1.0 in Nelore and 2.5 ± 0.8 in Holstein) had greater plasma AMH concentrations (P = 0.01 in Nelore and P = 0.003 in Holstein) than cycling heifers (1.1 ± 0.2 in Nelore and 0.6 ± 0.07 in Holstein). AMH concentrations in calves with or without pFSH were similar in both genetic groups (3.6 ± 1.1 vs 3.2 ± 1.0 in Nelore; 4.6 ± 1.2 vs 2.5 ± 0.8 in Holstein). In calves, positive correlations were observed between plasma AMH concentrations and the numbers of follicles >2 mm (r = 0.86, P < 0.0001 in Nelore; r = 0.78, P < 0.0001 in Holstein), cumulus-oocyte complexes (COCs) retrieved (r = 0.91, P < 0.0001 in Nelore; r = 0.82, P < 0.0001 in Holstein), COCs cultured (r = 0.71, P < 0.0001 in Nelore; r = 0.79, P < 0.0001 in Holstein), and blastocysts produced (r = 0.62, P = 0.0003 in Nelore; r = 0.58, P = 0.009 in Holstein), and these results were independent of pFSH treatment. In conclusion, calves had greater plasma AMH concentrations than cycling heifers. In addition, treatment with pFSH did not influence AMH concentrations in calves, regardless of the genetic group. More importantly, plasma AMH concentrations were positively correlated with the antral follicle population and the number of COCs retrieved, COCs cultured, and blastocysts produced in B indicus and B taurus calves. Therefore, AMH is a promising tool for selecting oocyte donor calves to maximize results during in vitro embryo production.

Paradoxical effects of bovine somatotropin treatment on the ovarian follicular population and in vitro embryo production of lactating buffalo donors submitted to ovum pick-up.

The aim of the present study was to evaluate the effect of bovine somatotropin (bST; 500mg) administration on lactating buffalo donors submitted to two different ovum pick-up (OPU) and in vitro embryo production schemes with a 7 or 14d intersession OPU interval. A total of 16 lactating buffalo cows were randomly assigned into one of four experimental groups according to the bST treatment (bST or No-bST) and the OPU intersession interval (7 or 14d) in a 2×2 factorial design (16 weeks of OPU sessions). The females submitted to OPU every 14d had a larger (P<0.001) number of ovarian follicles suitable for puncture (15.6±0.7 vs. 12.8±0.4) and an increased (P=0.004) number of cumulus-oocyte complexes (COCs) recovered (10.0±0.5 vs. 8.5±0.3) compared to the 7d interval group. However, a 7 or 14d interval between OPU sessions had no effect (P=0.34) on the number of blastocysts produced per OPU (1.0±0.1 vs. 1.3±0.2, respectively). In addition, bST treatment increased (P<0.001) the number of ovarian follicles suitable for puncture (15.3±0.5 vs. 12.1±0.4) but reduced the percentage (18.9% vs. 10.9%; P=0.009) and the number (1.4±0.2 vs. 0.8±0.1; P=0.003) of blastocysts produced per OPU session compared with the non-bST-treated buffaloes. In conclusion, the 14d interval between OPU sessions and bST treatment efficiently increased the number of ovarian follicles suitable for puncture. However, the OPU session interval had no effect on embryo production, and bST treatment reduced the in vitro blastocyst outcomes in lactating buffalo donors.

Relationship between circulating anti-Müllerian hormone (AMH) and superovulatory response of high-producing dairy cows.

The main objective of this study was to evaluate the relationship between circulating anti-Müllerian hormone (AMH) and superovulatory response of dairy cows. Holstein cows (n=72) were milked twice daily and housed and fed individually in tiestalls. All animals were synchronized and flushed at 70±3 d in milk (DIM), near peak production (39.6kg/d). Blood samples for AMH analysis were collected at 3 different stages of a synchronized estrous cycle [at a random stage (40±3 DIM), proestrus (50±3 DIM), and diestrus (57±3 DIM)]. Body weights were measured weekly from calving until embryo collection. Statistical analyses were performed with Proc CORR and Proc GLIMMIX of SAS (SAS Institute Inc., Cary, NC). The 3 AMH samples from individual cows were correlated and not influenced by day of cycle. Surprisingly, AMH tended to be negatively correlated with body weight loss from calving to embryo collection (r=-0.22). More importantly, average AMH was highly associated (r=0.65) with superovulation response (number of corpora lutea on the day of the flush, CLN), total structures collected (r=0.48), and total transferable embryos (r=0.37), but not percentage of fertilized embryos (r=-0.20) or degenerate embryos (r=0.02). When cows were classified into quartiles (Q) of circulating AMH (Q1=0.01 to 82.6pg/mL; Q2=91.1 to 132.5pg/mL; Q3=135.3 to 183.8pg/mL; Q4=184.4 to 374.3pg/mL), we observed a >2-fold difference between first and fourth AMH quartiles in superovulation response (CLN: Q1=12.0±1.5; Q2=14.7±2.0; Q3=17.2±1.2; Q4=25.6±1.5) and embryo production. In conclusion, circulating AMH concentration was strongly associated with superovulation response, and evaluation of AMH could be used to identify cows with greater responses to superstimulation and thus improve efficiency of superovulation programs in dairy cows.

Fenóis totais, atividade antioxidante e inibição da enzima tirosinase de extratos de Myracrodruon urundeuva Fr. All. (Anacardiaceae) / Total phenolics, antioxidant activity and tyrosinase enzyme inhibition by Myracrodruon urundeuva Fr. All. (Anacardiaceae) extracts

RESUMOOs radicais livres e outros oxidantes demonstram ser parcialmente responsáveis pelo envelhecimento e pelas doenças degenerativas associadas à produção de espécies reativas de oxigênio. Além disto, os compostos fenólicos são reconhecidamente detentores de elevada atividade antioxidante, que geralmente estão envolvidos em tratamentos de problemas de pigmentação da pele, que resultam em hiperpigmentações. Sendo assim este trabalho foi realizado para avaliar o conteúdo de fenóis totais, atividade antioxidante e a capacidade de inibição da tirosinase dos extratos das folhas e cascas do caule da espécie Myracrodruonurundeuva Fr. All. Para determinação do conteúdo de fenóis totais dos extratos orgânicos de M. urundeuva utilizou-se o reativo Folin-Ciocalteau, na avaliação da atividade antioxidante empregando o radical livre DPPH, enquanto que os testes de inibição da enzima tirosinase foram realizados utilizando L-tirosina. A concentração de fenóis totais foi de 77 mg EAG g-1 e 194 mg EAG g-1 nos extratos hexânico e metanólico das folhas e de 45 mg EAG g-1 e 193 mg EAG g-1 nos extratos hexânico e metanólico das cascas do caule. O potencial antioxidante dos extratos indicaram que o extrato metanólico das cascas do caule (10,9 ± 0,5 µg mL-1), em comparação ao hexânico (12,9 ± 0,2 µg mL-1) e ao BHT (220 ± 7,0 µg mL-1), possui atividade antioxidante levemente mais acentuada. No ensaio de inibição da tirosinase, o extrato metanólico das cascas do caule demonstrou a inibição da enzima em 42% após uma hora.

ABSTRACTFree radicals and other oxidants had demonstrated to be partially responsible for aging and for degenerative diseases associated with the production of reactive oxygen species. In addition, the phenolic compounds are recognized as holders of high antioxidant activity, which usually are involved in the treatment of pigmentation problems, resulting in hyper pigmentation. So this study was carried out in order to evaluate the content of total phenols, antioxidant activity and capacity inhibition of tyrosinase in extracts from leaves and stem barks of the species Myracrodruon urundeuva Fr. All. In order to determine the content of total phenols from organic extracts of M. urundeuva, a Folin-Ciocalteau reagent was employed in the evaluation of antioxidant activity,using the DPPH free radical, while the enzyme tyrosinase inhibition tests were performed using L-tyrosine. The amount of total phenols was 77 mg EAG g-1 and 194 in the hexane and methanolic extracts from the leaves and 45 mg EAG g-1 and 193 mg EAG g-1in the hexane and methanolic extracts of the stem barks. The antioxidant potential of extracts indicated that the methanolic extract of stem bark (10.9 ± 0.5 µg mL-1), when compared to the hexane (12.9 ± 0.2 µg mL-1) and BHT (220 ± 7.0 µg mL-1), presented a slightly higher antioxidant activity. For the tyrosinase inhibitiontrial , the methanolic extract ofstem barks indicated anenzyme inhibition of 42% after an hour.

Plasma anti-mullerian hormone: an endocrine marker for in vitro embryo production from Bos taurus and Bos indicus donors.

The aim of this study was to evaluate the association between plasma anti-mullerian hormone (AMH) concentration and in vitro embryo production (IVP) from Bos taurus (Holstein) and Bos indicus (Nelore) donors. A total of 59 Holstein (15 prepubertal heifers aged 8-10 mo, 15 cyclic heifers aged 12-14 mo, 14 lactating cows, and 15 nonlactating cows) and 34 Nelore (12 prepubertal heifers aged 10-11 mo, 10 prepubertal heifers aged 21-23 mo, and 12 cyclic heifers aged 24-26 mo) females were enrolled. All females underwent an ovum pick-up (OPU), without previous synchronization of the follicular wave, and IVP procedure. Immediately before the OPU procedure, blood samples were collected for subsequent AMH determination. A positive correlation was observed between the plasma AMH and number of in vitro embryos produced from Holstein (r = 0.36, P < 0.001) and Nelore (r = 0.50, P = 0.003) donors. For additional analyses, donors within each genotype were classified into 1 of 2 AMH categories (low or high) according to the average AMH concentration for each genotype. The results revealed that females classified as having high AMH presented a greater number of visible aspirated follicles (Holstein: 20.9 ± 1.5 vs 13.6 ± 0.9, P < 0.0001; Nelore: 54.3 ± 6.1 vs 18.6 ± 2.1, P < 0.0001) and a greater number of recovered cumulus-oocyte complexes (Holstein: 17.3 ± 1.5 vs 9.0 ± 0.9, P < 0.0001; Nelore: 45.3 ± 6.4 vs 13.4 ± 1.7, P < 0.0001). However, there was no difference in the blastocyst production rate (Holstein: 20.6% ± 4.0% vs 19.8% ± 4.2%, P = 0.60; Nelore: 33.7% ± 6.5% vs 27.4% ± 5.5%, P = 0.41, high and low AMH, respectively). Moreover, donors classified as having high AMH yielded a greater number of embryos produced per OPU (Holstein: 3.0 ± 0.7; Nelore: 7.0 ± 1.7) compared with those classified as having low AMH (Holstein: 1.2 ± 0.3, P = 0.04; Nelore: 2.2 ± 0.5, P = 0.007). In conclusion, although the plasma AMH concentration did not alter the ability of the cumulus-oocyte complex to reach the blastocyst stage, the AMH concentration in plasma can be an accurate endocrine marker for the in vitro embryo yield from either B. taurus (Holstein) or B. indicus (Nelore) donors. Therefore, AMH is a promising tool to enhance the overall efficiency of OPU-IVP programs in the field as a selective criterion for high embryo producing donors.

Superstimulation prior to the ovum pick-up to improve in vitro embryo production in lactating and non-lactating Holstein cows.

The present study evaluated the efficacy of superstimulation with p-FSH (Folltropin) before the ovum pick-up (OPU) on IVP in lactating and nonlactating Holstein donors. A total of 30 Holstein cows (15 lactating and 15 nonlactating) were blocked by lactation status to one of two groups (control or p-FSH), in a cross-over design. On a random day of the estrous cycle, all cows received an intravaginal progesterone device and 2.0 mg IM of estradiol benzoate (Day 0). Cows in the control group received no further treatment, whereas cows in the p-FSH group received a total dosage of 200 mg of p-FSH on Days 4 and 5 in four decreasing doses 12 hours apart (57, 57, 43, and 43 mg). On Day 7, the progesterone device was removed, and OPU was conducted in both groups (40 hours after the last p-FSH injection in the p-FSH-treated group). There was no difference between groups (P = 0.92) in the numbers of follicles that were aspirated per OPU session (17.2 ± 1.3 vs. 17.1 ± 1.1 in control and p-FSH-treated cows, respectively); however, p-FSH-treated cows had a higher (P < 0.001) percentage of medium-sized follicles (6-10 mm) at the time of the OPU (55.1%; 285/517) than control cows (20.8%; 107/514). Although recovery rate was lower (60.0%, 310/517 vs. 69.8%, 359/514; P = 0.002), p-FSH-treated cows had a higher blastocyst production rate (34.5%, 89/258 vs. 19.8%, 55/278; P < 0.001) and more transferable embryos per OPU session were produced in the p-FSH group (3.0 ± 0.5 vs. 1.8 ± 0.4; P = 0.02). Regardless of treatment, non-lactating cows had a higher blastocyst rate (41.9%, 106/253 vs. 13.4%, 38/283; P = 0.001) and produced more transferable embryos per OPU session (3.5 ± 0.5 vs. 1.3 ± 0.3; P = 0.003) than lactating cows. Thus, superstimulation of Holstein donors with p-FSH before OPU increased the efficiency of IVP. In addition, non-lactating donors had higher percentage of in vitro blastocyst development and produced more embryos per OPU session than lactating cows.

Donor category and seasonal climate associated with embryo production and survival in multiple ovulation and embryo transfer programs in Holstein cattle.

The present study investigated the effect of Holstein donor category (cows vs. heifers) and climate variation (hot vs. cooler season) on the efficiency of in vivo embryo production programs as well as embryo survival after transferred to Holstein recipient cows. A total of 1562 multiple ovulation (MO) procedures (cows: n = 609, and heifers: n = 953) and 4076 embryo transfers (ETs) performed in two dairy herds were evaluated. Donor cows had greater number of CLs (10.6 ± 0.6 vs. 7.5 ± 0.4; P < 0.0001) and ova/embryos recovered (7.6 ± 0.6 vs. 4.6 ± 0.4; P < 0.0001) compared with donor heifers. However, fertilization rate (47.9 vs. 82.4%; P < 0.0001) and proportion of transferable embryos (31.5 vs. 67.4%; P < 0.0001) were lower in donor cows than heifers, respectively. Regardless of donor category, the proportion of freezable embryos was less (P < 0.001) during hot season than in cooler season (21.4 vs. 32.8%). However, greater decline in the proportion of freezable embryos during the hot season was observed in cows (21.7 vs. 10.7%) compared with heifers (46.2 vs. 38.1%; P = 0.01). In contrast, the season on which the embryo was produced (hot or cool) did not affect pregnancy rate on Day 31 (30.5 vs. 31.7%; P = 0.45) and 45 (25.3 vs. 25.1%; P = 0.64) of pregnancy. Regardless of the season in which the embryos were produced, embryonic survival after transferring embryos retrieved from donor cows was greater on Days 31 (36.0 vs. 30.7%; P = 0.001) and 45 (28.3 vs. 23.1%; P = 0.001) of pregnancy when compared with embryos from donor heifers. In conclusion, MO embryo production efficiency decreased during the hot seasons both in cows and heifers; however, the decline was more pronounced in donor cows. Regardless of the embryo source, similar pregnancy rate was observed in the recipient that received embryos produced during the hot and cooler seasons. Curiously, embryos originating from donor cows had higher embryonic survival when transferred to recipient cows than embryos originating from heifers.

Relationships between fertility and postpartum changes in body condition and body weight in lactating dairy cows.

The relationship between energy status and fertility in dairy cattle was retrospectively analyzed by comparing fertility with body condition score (BCS) near artificial insemination (AI; experiment 1), early postpartum changes in BCS (experiment 2), and postpartum changes in body weight (BW; experiment 3). To reduce the effect of cyclicity status, all cows were synchronized with Double-Ovsynch protocol before timed AI. In experiment 1, BCS of lactating dairy cows (n = 1,103) was evaluated near AI. Most cows (93%) were cycling at initiation of the breeding Ovsynch protocol (first GnRH injection). A lower percentage pregnant to AI (P/AI) was found in cows with lower (≤ 2.50) versus higher (≥ 2.75) BCS (40.4 vs. 49.2%). In experiment 2, lactating dairy cows on 2 commercial dairies (n = 1,887) were divided by BCS change from calving until the third week postpartum. Overall, P/AI at 70-d pregnancy diagnosis differed dramatically by BCS change and was least for cows that lost BCS, intermediate for cows that maintained BCS, and greatest for cows that gained BCS [22.8% (180/789), 36.0% (243/675), and 78.3% (331/423), respectively]. Surprisingly, a difference existed between farms with BCS change dramatically affecting P/AI on one farm and no effect on the other farm. In experiment 3, lactating dairy cows (n = 71) had BW measured weekly from the first to ninth week postpartum and then had superovulation induced using a modified Double-Ovsynch protocol. Cows were divided into quartiles (Q) by percentage of BW change (Q1 = least change; Q4 = most change) from calving until the third week postpartum. No effect was detected of quartile on number of ovulations, total embryos collected, or percentage of oocytes that were fertilized; however, the percentage of fertilized oocytes that were transferable embryos was greater for cows in Q1, Q2, and Q3 than Q4 (83.8, 75.2, 82.6, and 53.2%, respectively). In addition, percentage of degenerated embryos was least for cows in Q1, Q2, and Q3 and greatest for Q4 (9.6, 14.5, 12.6, and 35.2% respectively). In conclusion, for cows synchronized with a Double-Ovsynch protocol, an effect of low BCS (≤ 2.50) near AI on fertility was detected, but change in BCS during the first 3 wk postpartum had a more profound effect on P/AI to first timed AI. This effect could be partially explained by the reduction in embryo quality and increase in degenerate embryos byd 7 after AI in cows that lost more BW from the first to third week postpartum.

Sucrose substitutes affect the cariogenic potential of Streptococcus mutans biofilms.

Streptococcus mutans is considered the primary etiologic agent of dental caries and contributes significantly to the virulence of dental plaque, especially in the presence of sucrose. To avoid the role of sucrose on the virulence factors of S. mutans, sugar substitutes are commonly consumed because they lead to lower or no production of acids and interfere with biofilm formation. This study aimed to investigate the contribution of sugar substitutes in the cariogenic potential of S. mutans biofilms. Thus, in the presence of sucrose, glucose, sucralose and sorbitol, the biofilm mass was quantified up to 96 h, the pH of the spent culture media was measured, the expression of biofilm-related genes was determined, and demineralization challenge experiments were conduct in enamel fragments. The presence of sugars or sugar substitutes profoundly affected the expression of spaP, gtfB, gtfC, gbpB, ftf, vicR and vicX in either biofilm or planktonic cells. The substitution of sucrose induced a down-regulation of most genes involved in sucrose-dependent colonization in biofilm cells. When the ratio between the expression of biofilm and planktonic cells was considered, most of those genes were down-regulated in biofilm cells in the presence of sugars and up-regulated in the presence of sugar substitutes. However, sucralose but not sorbitol fulfilled the purpose of reducing the cariogenic potential of the diet since it induced the biofilm formation with the lowest biomass, did not change the pH of the medium and led to the lowest lesion depth in the cariogenic challenge.

Effects of acute feed restriction combined with targeted use of increasing luteinizing hormone content of follicle-stimulating hormone preparations on ovarian superstimulation, fertilization, and embryo quality in lactating dairy cows.

Multiple metabolic and hormonal factors can affect the success of protocols for ovarian superstimulation. In this study, the effect of acute feed restriction and increased LH content in the superstimulatory FSH preparation on numbers of ovulations, fertilization, and embryo quality in lactating dairy cows was evaluated. Two experiments were performed using a Latin square design with treatments arranged as a 2 × 2 factorial: feed restriction (FR; 25% reduction in dry matter intake) compared with ad libitum (AL) feeding, combined with high (H) versus low (L) LH in the last 4 injections of the superstimulatory protocol. As expected, FR decreased circulating insulin concentrations (26.7 vs. 46.0 µU/mL). Two analyses were performed: one that evaluated the complete Latin square in experiment 2 and a second that evaluated only the first periods of experiments 1 and 2. For both analyses, follicle numbers, ovulation rates, and corpora lutea on d 7 were not different. In the first period analysis of experiments 1 and 2, we observed an interaction between feed allowance and amount of LH on fertilization rates, percentage of embryos or oocytes that were quality 1 and 2 embryos, and number of embryos or oocytes that were degenerate. Fertilization rates were greater for the AL-L (89.4%) and FR-H (80.1%) treatments compared with the AL-H (47.9%) and FR-L (59.9%) treatments. Similarly, the proportion of total embryos or oocytes designated as quality 1 and 2 embryos was greater for AL-L (76.7%) and FR-H (73.4%) treatments compared with AL-H (35.6%) and FR-L (47.3%) treatments. In addition, the number of degenerate embryos was decreased for AL-L (1.3) and FR-H (0.4) treatments compared with the AL-H (2.6) and FR-L (2.3) treatments. Thus, cows with either too low (FR-L) or too high (AL-H) insulin and LH stimulation had lesser embryo production after superstimulation because of reduced fertilization rate and increased percentage of degenerate embryos. Therefore, interaction of the gonadotropin content of the superstimulatory preparation with the nutritional program of the donor cow needs to be considered to optimize success of ovarian superstimulatory protocols.

Effects of deep-horn AI on fertilization and embryo production in superovulated cows and heifers.

The primary objective of this study was to determine the effect of site of semen deposition on fertilization rate and embryo quality in superovulated cows. The hypothesis was that deposition of semen into the uterine horns would increase the fertilization rate compared with deposition of semen into the uterine body. The secondary objective was to evaluate the effect of uterine environment on fertilization rate and embryo quality. It was hypothesized that subclinical endometritis at the onset of superstimulation would decrease the fertilization rates and embryo quality. In experiment 1, 17 superovulated heifers were randomly assigned to receive artificial insemination (AI) into the uterine body or uterine horns. The total number of fertilized structures and fertilization rate from superovulated heifers was increased (P = 0.04 and P = 0.02, respectively) when semen was deposited into the uterine horns compared with the uterine body. Other embryo characteristics did not differ based on the site of semen deposition. In experiment 2, 14 lactating dairy cows were superovulated twice and were randomly assigned to receive AI into the uterine body or deep into the uterine horns using a crossover design. Neither fertilization rate nor any other embryo characteristics were improved when semen was placed deep into the uterine horns compared with the uterine body. In experiment 3, 72 superovulated lactating dairy cows were randomly assigned to receive AI into the uterine body or uterine horns. Before initiation of superstimulatory treatments, an endometrial cytology sample was collected from each cow. Ova/embryos were collected by a nonsurgical technique at 70 ± 3 days in milk. Similar to experiment 2, neither fertilization rate nor any other embryo characteristics differed based on the site of semen deposition in experiment 3. The percentage of cows with subclinical endometritis did not differ between treatments. Interestingly, there was a tendency (P = 0.09) for a reduction in embryo recovery rate and a reduction (P = 0.01) in the fertilization rate for cows with subclinical endometritis. In conclusion, deposition of semen into the uterine horns rather than into the uterine body did not improve the fertilization rate or embryo quality in superovulated cows. Subclinical endometritis decreased the fertilization rate in superovulated cows.