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Crude glycerin has been used as an alternative energy source in animal feeding and can thus change both the animal's performance and the levels of gene expression related to energy production process and the antioxidant system, since the effect of glycerin depends on its degree of purity in the diet. The aim of this study was to evaluate the effect of crude glycerin inclusion (0, 6 and 12%) in the diet has on performance characteristics and mRNA abundance of genes associated with the mitochondrial function (uncoupling protein (UCP), cytochrome C oxidase subunit III (COX III) and adenine nucleotide transporter (ANT)) and those that combat the reactive oxygen species (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)) in the liver and muscle of broilers at 42 days of age. Total RNA was extracted from the tissues, and cDNA was amplified using specific primers for the genes under study through real-time reverse transcription polymerase chain reaction; the endogenous gene used was β-actin. There was no difference between glycerin concentrations for weight gain, feed intake or feed conversion. Greater expression of UCP at muscle and higher GPx expression at liver were observed in broilers fed 12% glycerin. In conclusion, the addition of 12% glycerin to broiler diets increased the expression of UCP and GPx , but did not change broiler performance. Therefore, glycerin can be used as an alternative ingredient without losses. Glycerin represents an alternative of reducing costs in broiler production. We evaluate whether glycerin interferes in the performance characteristics and in the expression of mitochondrial and antioxidant genes. Although the expression of UCP and GPx genes has been increased, we conclude that glycerin can be used as an alternative in poultry feed without lost performance. [ABSTRACT FROM AUTHOR]

Follicular dynamics and the expression of candidate genes using real-time polymerase chain reaction (PCR) were compared during the oestrous cycle of pig breeds with high (commercial line; n = 24) and low (local Brazilian Piau; n = 21) ovulation rates and prolificacy. Gilts were killed on Days 0, 4, 10 and 18 of the oestrous cycle and visible ovarian follicles were classified by follicular diameter. Recovered cumulus -- oocyte complexes were classified as normal or atretic and frozen in liquid nitrogen until RNA extraction. Low ovulation rates and/or prolificacy in Piau gilts was associated with a different pattern of follicle development, with lower numbers of small follicles on Day 18, fewer large follicles on Days 0 and 18 (P ≤ 0.05) and a higher proportion of atretic follicles on Days 0 and 18 (P ≤ 0.05). Compared with commercial line gilts, less-prolific Piau gilts exhibited higher expression of apoptotic genes during luteolysis (CASP3 and FASL; P ≤ 0.05), decreased expression of TGFBR2 and BAX mRNA in the corpus luteum (P ≤ 0.05), higher expression of apoptotic genes (FAS, BCL2 and CASP8; P ≤ 0.05) in granulosa cells and a greater abundance (P ≤ 0.05) of genes controlling oocyte-secreted factors (GDF9, BMP15 and BMP6), suggesting underlying mechanisms controlling differences in follicular development, ovulation rate and inherent prolificacy in this pig breed. [ABSTRACT FROM AUTHOR]

During each estrous cycle, more than 99% of the ovarian follicles undergo a degenerative process known as atresia. The p53 is an antiproliferative transcription factor that enhances the transcription rate of important genes in the apoptotic pathway. The aim of the current study was to investigate the pattern of p53 mRNA expression during estrous cycle in the pig ovary by real-time PCR technique. Sixteen prepubertal gilts (Landrace × Large White × Pietrain) were obtained from the pig farm at the Universidade Federal de Viçosa (Viçosa, MG, Brazil). The estrous cycle was synchronized with P.G. 600®(Intervet/Schering-Plough Animal Health, Millsboro, DE, USA; 400 IU eCG and 200 IU hCG). The onset of estrus was checked twice a day using a mature boar. The gilts, n= 4 per group, were slaughtered on Days 0, 6, 12, and 18 of estrous cycle. Granulosa cells from follicles were collected by vacuum aspiration and washed in PBS by centrifugation at 5.000 × gfor 6 min, and the RNA was extracted using the RNeasy Mini Kit (Qiagen, Valencia, CA, USA). The ovarian cortex was stored in RNAlater (Ambion, Austin, TX, USA) and frozen at -80°C. Its RNA was extracted from 30 mg using the same Kit. For each animal in each stage, a pool of equivalent amounts of RNA from granulosa cells and ovary cortex was reverse transcribed with SuperScript III/RNaseOUT Enzyme Mix (Invitrogen Life Technologies, Carlsbad, CA, USA) to evaluate gene expression for the ovary as a whole. Quantitative real-time PCR was performed using SYBR green fluorescent detection system on ABI Prism 7300 Sequence Detection Systems (Applied Biosystems, Foster City, CA, USA). The primers were designed from swine sequences available at GenBank. The linearity of amplification for p53 mRNA was similar to the endogenous control gene, glyceraldehyde-3-phosphate dehydrogenase. Reactions were performed using 200 nM primer and 100 ng of the cDNA per reaction for both genes. The thermal cycling conditions consisted of 40 cycles of 30 s of melting at 95°C followed by 30 s of annealing and extension at 60°C. After amplification, a melting curve analysis was performed to validate the absence of non-specific products. Gene expression data were presented using the 2ACt method (Livak and Schimittgen 2001). The results of gene expression were analyzed using linear regression after transformation ln(2ACt + 1) as the dependent variable and days of estrous cycle as independent variables using the general linear model procedure (SAS Institute, Inc., Cary, NC, USA). The mRNA expression was not affected by days of estrous cycle (P= 0.86). In rats, the expression of p53 mRNA in granulosa cells has been already described. Despite the fact that no difference has been found during the estrous cycle in this study, the expression of this messenger in the pig ovary seems to be undescribed until now. In the future, for a better understanding of p53 regulation in the pig, gene expression analysis in different follicle sizes and physiological status will be presented by our group to examine the expression patterns of this gene, as well as other related ones, included in this apoptotic pathway. [ABSTRACT FROM AUTHOR]

Heterospermic AI is commonly used in swine despite preventing precise evaluation of individual boar fertility. The present study compared the contribution of four boars (A, B, C and D) for reproductive performance and for paternity using homospermic and heterospermic (AB, AC, AD, BC, BD and CD) AI (n = 204 for homospermic AI; n = 307 for heterospermic AI). Blood samples from the four boars, from all sows inseminated with heterospermic doses and from the umbilical cords of their piglets, as well as tissue smears from mummified fetuses, were genotyped using single nucleotide polymorphisms (SNPs). Differences among boars were detected for the in vitro oocyte penetration rate and for the number of spermatozoa per oocyte (P < 0.05), but not for sperm motility, mitochondrial functionality and integrity of the membrane, acrosome and DNA (P > 0.05). Homospermic and heterospermic AI resulted in similar (P > 0.05) farrowing rates (90.5% and 89.9%, respectively) and total litter size (12.4 ± 0.4 and 12.7 ± 0.7, respectively). Farrowing rate was lower for Boar B than for Boar C (P < 0.05), but no other differences in reproductive performance among boars were observed with homospermic AI. The SNPs determined the paternity of 94.2% of the piglets sired by heterospermic AI. In the AC pool, paternity contribution per boar was similar (P > 0.05), but differences between boars occurred in all other pools (P < 0.05). Boar D achieved the greatest paternity contribution in all pools and parity categories (nearly 60%), whereas Boar B sired the fewest piglets (at most 40%). Reproductive performance was similar with homospermic and heterospermic AI, but differences in performance among boars undetected with homospermic AI were only evident after genotyping the piglets sired through heterospermic AI. Although it is commonly used in swine farms, heterospermic AI does not allow precise evaluation of boar fertility. The reproductive performance and the paternity contribution of four boars (A, B, C and D) were compared in this study using homospermic and heterospermic AI in 511 sows. Differences among boars were only identified after genotyping the piglets sired through heterospermic AI. [ABSTRACT FROM AUTHOR]

This study was designed to monitor the biochemical profiles of serum and follicular fluid (FF) of postpartum dairy cows during the summer (n = 30) and winter (n = 30). Blood and FF (follicles ≥ 9 mm) were obtained from Girolando cows at 30,45, 60, 75 and 90 days postpartum. The samples were collected and analysed to determine glucose, total cholesterol (TC), triglyceride (TG), urea, sodium (Na), potassium (K) and calcium (Ca) levels. Throughout the study, the following clinical variables were measured: rectal temperature (RT), respiratory rate (RR) and body condition score (BCS). In addition, the temperature humidity index (THI) was calculated for each season. During the summer season, THI was higher, BCS decreased, there was an increase in RT, and glucose, urea, Na and K serum levels were decreased (P < 0.05). The levels of TC, TG, urea, K and Ca in follicular fluid increased (P < 0.05). Positive correlations (P < 0.05) were observed between the serum and FF levels for glucose (r = 0.29), TC (r = 0.24) and Ca (r = 0.30). Therefore, the biochemical profile of serum and FF of dairy cows under summer heat-stress conditions demonstrates marked changes that may impair fertility during lactation. [ABSTRACT FROM AUTHOR]