SMAD6 inhibits granulosa cell proliferation and follicle growth rate in carrier and noncarrier heifers of the Trio allele.

In brief: Follicle selection is a key event in monovular species. In this manuscript, we demonstrate the role of SMAD6 in promoting decreased granulosa cell proliferation and follicle growth rate in carriers vs noncarriers of the Trio allele and after vs before follicle deviation. Abstract: Cattle are generally considered a monovular species; however, recently, a bovine high fecundity allele, termed the Trio allele, was discovered. Carriers of Trio have an elevated ovulation rate (3-5), while half-sibling noncarriers are monovular. Carriers of the Trio allele have overexpression in granulosa cells of SMAD6, an inhibitor of oocyte-derived regulators of granulosa cell proliferation and differentiation. In experiment 1, follicle size was tracked for each follicle during a follicular wave. Follicle growth rate was greater before vs after follicle deviation in both carriers and noncarriers. Additionally, follicle growth rate was consistently less in carriers vs noncarriers. In experiment 2, we collected granulosa cells from follicles before and after deviation for evaluation of granulosa cell gene expression. Granulosa cell proliferation was less in carriers vs noncarriers and after vs before follicle deviation (decreased expression of cell cycle genes CCNB1 and CCNA2). The decreased granulosa cell proliferation in noncarriers after deviation was associated with increased SMAD6 expression. Similarly, in experiment 3, decreased expression of SMAD6 in granulosa cells of noncarriers cultured in vitro for 60 h was associated with increased expression of cell cycle genes. This suggests that SMAD6 may not just be inhibiting follicle growth rate in carriers of Trio but may also play a role in the decreased follicle growth after deviation in noncarriers. The hypotheses were supported that (1) follicle growth and granulosa cell proliferation decrease after deviation in both carriers and noncarriers and that (2) granulosa cell proliferation is reduced in carriers compared to noncarriers.

Development of a novel 21-day reinsemination program, ReBreed21, in Bos indicus heifers.

The aim was to develop a program for resynchronization of ovulation (ReBreed21) that allowed reinsemination of non-pregnant Bos indicus heifers every 21 d using timed AI (TAI) without the need for detection of estrus. The Rebreed21 program begins 12 d after previous TAI (Day 0) by inserting an intravaginal P4 implant (Day 12) that is removed 7 d later (Day 19) combined with treatment with 300 IU of eCG. On Day 21, early pregnancy diagnosis (Doppler PD) is performed based on CL vascularity. Non-pregnant (NP) heifers immediately received AI combined with 100 µg of GnRH. The program is replicated 12 d after second TAI to produce a breeding season (BS) of 42 d with 3 potential TAIs. Two experiments were conducted as a proof of concept for this rapid rebreeding program. In Experiment 1, 76 heifers were enrolled in ReBreed21, as explained above. In Experiment 2, 300 Nellore heifers were synchronized for 1st TAI and randomly assigned to one of two groups: ReBreed21 (n = 147) or another early resynchronization procedure, Resynch14 (n = 153) with P4 implant inserted 14 d after previous TAI plus 50 mg of long-acting injectable P4; 8 d later P4 implant removed (Day 22) and early Doppler PD performed; NP heifers received 150 µg of cloprostenol, 0.5 mg of ECP, and 300 IU of eCG with TAI on Day 24. In both experiments, the largest follicle (LF) was measured at each Resynch TAI. Ultrasound was later used to confirm the early Doppler PD and to determine ovulation (OV) to Resynch at 12 d after TAI in ReBreed21 (Day 33 of pregnancy) and 14 d after TAI in Resynch14 (Day 38 of pregnancy). Final PD was performed 40 d after 3rd TAI. Results for Experiment 1 were: diameter of LF 11.8 ± 0.23 mm; 88.9% OV; 20.5% false positives; 38.1% P/AI at 1st TAI; 44.4% overall P/AI for ReBreed21 TAIs; 72.3% total pregnant at end of BS. In experiment 2, Rebreed21 vs. Resynch14 were different for: diameter of LF (10.9 ± 0.17 vs. 10.0 ± 0.17 mm, P = 0.0003), heifers with LF < 8.5 mm (10.2 vs. 26.4%, P = 0.04), or LF ≥ 11 mm (50.0 vs. 37.2%, P = 0.001), and P/AI at first TAI (29.3% [43/147] vs. 20.3% [31/153], P = 0.074) but similar for OV (overall 86.8% [239/275], P = 0.82), false positives (P = 0.52) overall P/AI for Resynch TAIs (33.6 vs. 28.8%, P = 0.4), and total pregnant at end of BS (58.5% [86/147] vs. 55.6% [85/153], P = 0.64). In addition, median time to pregnancy was 9 d earlier (P = 0.0007) for ReBreed21 than Resynch14. Thus, ReBreed21 is a novel protocol that allows earlier reinseminations than Resynch14 but with similar fertility.

Lung function and functional capacity in school age children / Função pulmonar e capacidade funcional de escolares

Abstract Introduction: Six-minute walk test (TC6') and peak expiratory flow (PEF) can be influenced by variables like gender, age and body mass index (BMI). In the school context, these tests can identify losses caused by sedentary habits and/or manifestation of overweight/obesity. Nevertheless, although widely studied in the adult context, they have not been properly clarified in the child public. Objective: To assess the PEF and TC6' between students in the public and private network and to correlate them with factors like age, gender and BMI. Methods: 39 male and female children between eight and ten years of age were selected for the study. The TC6' was held at a sports court. The child was instructed to walk at maximum speed for six minutes and the PEF test took place in accordance to the recommendations by Pereira et al (1). Results: No significant correlation was found between the BMI and the PEF and TC6' scores. No significant correlation was found between sex and PEF, with measures within normal parameters for the entire sample. The EPF measures did not influence the distance walked in the TC6'. A significant correlation was found between sex and distance walked in the TC6' only among male children attending public schools. Conclusion: Both sex and BMI did not influence the PEF measures which, in turn, does not seem to have influenced the distance the sample walked in the TC6'. Also concerning the TC6', only the children from public school reached the normal scores proposed in the literature.

Resumo Introdução: Testes de caminhada de seis minutos (TC6') e pico de fluxo expiratório (PFE) podem ser influenciados por variáveis tais como, gênero, idade e índice de massa corporal (IMC). Em âmbito escolar são capazes de identificar prejuízos gerados por hábitos sedentários e/ou manifestação de sobrepeso/obesidade. No entanto, embora amplamente estudados no meio adulto, ainda não estão bem esclarecidos no público infantil. Objetivo: Avaliar o PFE e TC6' entre escolares da rede pública e privada, bem como correlacioná-los com fatores tais como idade, gênero e IMC. Métodos: Participaram do estudo 39 crianças de ambos os gêneros e idades compreendidas entre 8 e 10 anos. O TC6'ocorreu em quadra poliesportiva, a criança orientada a caminhar em velocidade máxima por seis minutos e o teste de PFE, conforme Pereira et al. (1) Resultados: Não houve correlação significativa entre o IMC e os valores obtidos de PFE e TC6'. Não houve correlação significativa entre sexo e PFE, cujas medidas ficaram de acordo com a normalidade para toda a amostra. As medidas de PFE não influenciaram a distância percorrida no TC6'. Houve correlação significativa entre o sexo e distância percorrida no TC6' apenas entre as crianças do sexo masculino, pertencentes às escolas públicas. Conclusão: Tanto o sexo quanto o IMC não influenciaram as medidas de PFE, e este por sua vez, não parece ter exercido influência sobre a distância percorrida no TC6' da amostra. Ainda no que tange ao TC6', apenas as crianças oriundas de escolas públicas alcançaram os valores de normalidade propostos pela literatura.