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Selection for female farrowing performance is challenging to the swine industry due to the low heritability. Previous studies have suggested testis size as an indicator of reproductive performance. Thus, to determine the effectiveness of measuring testis size to identify sires of reproductive superior sows, 161 Yorkshire and Landrace boars were measured for width (TW) and area (TA). Farrowing performance was collected for 384 sows, daughters of 13 of the 161 boars. For heritability estimates ( h 2), the fixed effects of age (boar traits only), breed, contemporary group (CG), and parity (sow traits only), and the random effects of animal and permanent environment (sow traits only) were included in the model. Poisson phenotypic regression of the reproductive traits of daughters on the testis size of sires was performed including the fixed effects of parity, breeds of sow and sire, and TW or TA, and the random effects of sow and CG. For testis size, h2 were 0.69 and 0.66 for TA and TW, respectively. For reproductive traits, h2 ranged from 0.01 to 0.18. There were quadratic and linear relationships (P

In the current study we have performed two experiments to evaluate the effects of adipogenic induction media on dedifferentiated fat (DFAT) cells redifferentiation into mature adipocytes. In experiment 1, we aimed to evaluate whether it is necessary to use insulin in the induction media to allow DFAT cells differentiation into mature adipocytes by establishing two experimental treatments where insulin was either withdrawn from the culture medium, after 72 h of a normal induction period (Treatment 1: Insulin - ) or kept in culture media (Treatment 2: Insulin + ) for 16 d. In experiment 2, we aimed to evaluate if the lack of 3-isobutyl-1-methylxanthine (IBMX) in the induction medium would affect the differentiation of DFAT cells into mature adipocytes. For that, DFAT cells were induced to differentiate into lipid assimilating adipocytes using an induction medium containing IBMX (Treatment 1: IBMX + ) or without IBMX (Treatment 2: IBMX - ) during the first 72 h of induction. In both experiments we have evaluated the mRNA expression of lipid metabolism markers and cell morphology through Oil-Red staining as indicators of differentiation of DFAT cells into lipid-assimilating cells. The results of Experiment 1 revealed no differences in mRNA expression for any of the lipid metabolism markers with exception of GLUT4 ( P =0.02), which was greater in Insulin - compared to Insulin + treatment. Similarly, no differences were observed for mRNA expression of adipogenic markers between IBMX + and IBMX - treatments with exception of FABP4 ( P =0.01), which was greater for the IBMX - compared to IBMX + treatment. In both experiments we did not observed any differences in cell morphology among treatments. Our results suggest that neither insulin nor IBMX are required to accelerate redifferentiation process of pig-derived DFAT cells.

We investigated how feed restriction at 50% of maintenance requirements during different stages of gestation affects the transcriptome of newborn goats' skeletal muscle. Fourteen pregnant dams were randomly assigned into one of the following dietary treatments: animals fed at 50% of maintenance requirement from 8-84 d of gestation and then fed at 100% of maintenance requirement from day 85 of gestation to parturition (RM, n = 6), and animals fed at 100% of maintenance requirement from 8-84 d of gestation and then fed at 50% of maintenance requirement from day 85 of gestation to parturition (MR, n = 8). At birth, samples of offspring's Longissimus muscle were collected for total RNA extraction and sequencing. Our data showed 66 differentially expressed (DE) genes (FDR < 0.05). A total of 6 genes were upregulated and 60 downregulated (FDR < 0.05) in the skeletal muscle of the newborns resulting from treatment RM compared with MR. Our results suggest that the DE genes upregulated in newborn goats' skeletal muscle from the RM group compared to MR, included genes related to satellite cells, and genes that indicates impaired insulin sensitivity and changes in the composition of intramuscular fat. The DE genes upregulated in newborn goats' skeletal muscle from the MR group compared to RM, are also related to impaired insulin sensitivity, as well as a predominantly oxidative metabolism and cellular oxidative stress. However, protective mechanisms against insulin sensitivity and oxidative stress may have been augmented in the skeletal muscle of offspring from MR treatment compared to RM, in order to maintain cellular homeostasis.

Feed efficiency is of great importance to the swine industry, yet few studies have evaluated the robustness of pigs selected for increased feed efficiency based on residual feed intake (RFI) when challenged with disease. RFI is calculated as the difference between the observed and expected feed intake. The objective of this study was to assess the effect of porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) infection on lines of pigs divergently selected for RFI. Hypothesizing that the more feed efficient low RFI (LRFI) pigs would be more affected by PRRSV-infection, 97 piglets from LRFI and 99 piglets from high RFI (HRFI) selection lines were experimentally infected with the NVSL 97-7985 PRRSV isolate 1 to 3 weeks post-weaning. Pig body weight was recorded weekly and used to calculate average daily gain (ADG). For comparison, ADG was also evaluated on 489 non-challenged LRFI and HRFI pigs housed in a separate facility. Viral load (VL) was quantified as area under the curve for 0–21 days post-infection (dpi) of the log of PCR-based serum viremia. Antibody level was analyzed from serum samples collected at 4, 7, and 11 dpi by PRRS ELISA and MAGPIX assays to quantify PRRSV-specific IgG antibody and total antibody, respectively, during the early stages of PRRSV-infection. There was a tendency for pigs from the LRFI line to have lower VL (P=0.09), greater ADG (P=0.10), and be more likely to survive the PRRSV-challenge (P=0.06) than pigs from the HRFI line. However, joint analysis of challenged and non-challenged pigs showed a significant interaction between RFI line and challenge status (P=0.04), which demonstrated that growth of the LRFI line was less affected by PRRSV-challenge than growth of the HRFI line. Additionally, a significant interaction between RFI line and dpi for the ELISA (P

This study was developed aiming to evaluate the effects of maternal feed-restriction ond evelopment of gastrointestinal tract (GIT) of bovine fetus at different gestational stages. Feed-restricted cows were fed 1.2 times the maintenance level while the control group was fed ad libitum. Pregnant cows were slaughtered at 136, 189, 239, and 269 days of gestation and gastrointestinal tracts of the fetuses were evaluated. No effects of maternal nutrition on body weight (P 1⁄4 0.17) and body length (P 1⁄40.13) of the fetuses were observed. No major effects of feed restriction on GIT mass of the fetuses were observed (P 1⁄4 0.51). However, the weight of small intestine per unit of body weight was 11.24% greater (P 1⁄40.04) in fetuses from restricted dams. Additionally, the length of small intestine and its villi were 12.93% and 16.44% respectively greater (P o .001) in fetuses from restricted dams compared to those from non-restricted dams. These data indicates that maternal feed-restriction does not affect the development of most of fetal gastrointestinal parts besides small intestine which in turn increases its surface area as a response of maternal feed restriction.