The objective of this study was to evaluate the effects of different protocols (P1, P2, and P3) of boldenone undecylenate (BU) and stanozolol (ST) on markers of liver and kidney function and variables of oxidative stress in these organs. For this, 54 male Wistar rats were divided into nine groups of six animals each. Each animal received intramuscularly 5.0 mg kg of BU or ST once a week for 4 weeks (P1); 2.5 mg kg of BU or ST once a week for 8 weeks (P2); and 1.25 mg kg of BU or ST once a week for 12 weeks (P3). For each protocol, a control group was used, and they received 0.1 ml of olive oil intramuscularly. Blood and fragments of liver and kidney were collected for alanine aminotransferase activity (ALT), alkaline phosphatase, albumin, creatinine, cholesterol, total protein, triglycerides, urea, reactive oxygen species, thiobarbituric acid reactive substances, total thiols, and glutathione evaluation. The results show that the BU in doses of 5 (day 30) and 2.5 mg kg (day 60) changes the ALT seric activity, possibly showing a hepatotoxic effect. High doses of BU may lead to increased levels of cholesterol (protocol P1) possibly due to inhibition of the normal steroid biosynthesis process. All protocols used caused changes in the redox balance of the organs studied (except in the liver, protocol P2), which indicates that these drugs might be harmful even at low doses.

Microsatellites or short tandem repeats (STRs), DNA markers relatively abundant in the genome, have a high degree of polymorphism and therefore great potential for characterizing populations. The present study estimates genetic variability in a set of four microsatellites (BMS3013, BMS3004, HEL10 and TGLA122) in a Brazilian hybrid bovine breed (5/8 Aberdeen Angus x 3/8 Nelore). The objectives were to determine the effect of crossbreeding and selection in these animals' genetic diversity as well as to discover the herd's genetic relationship with that of other breeds. Low diversity was verified in BMS3013 and high diversity was detected in BMS3004, HEL10 and TGLA122. Two alleles in TGLA122 are described here for the first time (TGLA122*155 and TGLA122*163). These genes are possibly characteristics of Zebu animals since they have not been found in other taurine samples so far investigated. Low interpopulational diversity was observed among taurine cattle populations, and clusters obtained on TGLA122 phylogenetic trees agreed with the bovine herd's geographic origin. Therefore, despite TGLA122's high polymorphism and high levels of intrapopulational diversity, the system engenders consistent bovine phylogenies. We detected an intriguingly high similarity between Brangus Ibagé and Red Angus since the former is a hybrid having 3/8 of Nelore genes. Either these animals' environment or genetic selective practices applied to the breed probably favor the Angus genotype.
Microssatélites ou repetições curtas em tandem (STRs) são marcadores moleculares de relativa abundância no genoma e apresentam alto grau de polimorfismo, constituindo-se numa excelente ferramenta para a caracterização das populações. Este trabalho estimou a variabilidade genética de quatro microssatélites (BMS3013, BMS3004, HEL10 e TGLA122) em um rebanho híbrido de bovinos brasileiros (5/8 Aberdeen Angus x 3/8 Nelore), com os objetivos de verificar o efeito do cruzamento e das práticas seletivas na composição genética do rebanho e avaliar as relações genéticas destes animais com outras populações bovinas mundiais. Verificou-se uma baixa diversidade no BMS3013, mas alta variabilidade nos STRs BMS3004, HEL10 e TGLA122. No TGLA122 dois alelos novos estão sendo descritos pela primeira vez (TGLA122*155 e TGLA122*163). É possível que esses genes sejam característicos de Zebu, uma vez que não ocorrem em outras raças taurinas investigadas até o momento. Uma baixa diversidade interpopulacional foi observada entre as populações taurinas, e os agrupamentos obtidos nas filogenias baseadas no TGLA122 foram coerentes com a origem geográfica dos rebanhos. Assim, apesar do TGLA122 ser altamente polimórfico e apresentar altos níveis de diversidade intrapopulacional, ele é um marcador muito eficiente para a construção de filogenias bovinas. Detectou-se uma grande similaridade entre Brangus Ibagé e Red Angus, apesar do Brangus Ibagé ser um rebanho híbrido com 3/8 de genes Nelore. É possível que o ambiente onde esses animais vivem ou as práticas seletivas aplicadas ao reba...

In the detection phase of a bovine marker assisted selection program, this paper investigated the genetic variability of three microsatellites on the chromosome 18 (BTA 18). The possible associations between genotypes or alleles of these markers versus weight at first calving and a lifetime calving interval (as indicators of reproductive performance) were evaluated in a beef cattle herd (5/8 Aberdeen Angus x 3/8 Nelore). Eleven alleles were detected in TGLA227 and ILSTS002 and three in BMS3004, the most frequent being TGLA227*79, ILSTS002*133, ILSTS002*135 and BMS3004*129. Polymorphic information content ranged from 0.41 to 0.84, while heterozygosity ranged from 49% to 86%, with an average value of 77%. The association analyses performed between genotype classes for the genetic markers versus weight at first calving indicated no significant result. Also, no correlation was observed between calving interval (CI) and TGLA227 genotypes. However, positive associations were detected between ILSTS002 and BMS3004 and CI. Animals carrying at least one ILSTS002*135 allele presented a CI about 39 days longer than the individuals with other genotypes; animals heterozygous for BMS3004 presented a CI about 35 days shorter than the homozygous. On these grounds, it can be concluded that these markers can be useful as an aid to fertility selection, in this herd.

We investigated the expression of calcium-dependent phospholipid binding protein annexin-II (Ann-II) messenger RNA (mRNA) during preantral follicle development and in oocytes from antral follicles of different diameters (< 3 mm, 5 to 8 mm and > 8 mm). The action of retinol on Ann-II mRNA expression in mature oocytes was also examined. Only oocytes from secondary preantral follicles expressed Ann-II mRNA and at the germinal vesicle stage expression by oocytes from follicles larger than 8 mm was significantly higher (p < 0.05) compared with oocytes from follicles smaller than 3 mm or between 5 and 8 mm. Ann-II mRNA expression by metaphase II oocytes from follicles larger than 8 mm was significantly higher (p < 0.05) than that from oocytes from follicles smaller than 3 mm, with oocytes from both these size-classes showing similar levels of Ann-II mRNA expression as oocytes recovered from 5-8 mm follicles. In the presence of retinol, Ann-II mRNA expression was higher than when retinol was absent (p < 0.05). Our data indicate that Ann-II mRNA expression is highest in competent oocytes and that retinol increases Ann-II mRNA and may be involved in the regulation of oocyte competence by decreasing the translation and/or degradation of Ann-II mRNA.