Composición corporal y parámetros sanguíneos de lechones Alentejanos y Large White × Landrace recién nacidos

This study aimed to compare the body composition and some blood parameters [(glucose, albumin and insulin-like growth factor 1 (IGF-1)] of newborn piglets farrowed by unselected Alentejano (AL) or conventional genotype [(Large-White × Landrace (LL)]. Carcasses (12 of each genotype) and blood samples were obtained from a total of 34 litters (18 AL, 16 LL). Gestation length was 4d shorter in AL sows compared with LL sows. When adjusted for birth weight, carcasses of AL piglets showed higher percentages of dry matter (PEl objetivo de este estudio fue comparar la composición corporal y los parámetros sanguíneos [albúmina, glucosa y factor de crecimiento insulínico tipo 1 (IGF-1)] de lechones recién nacidos procedentes de cerdas de raza no seleccionada Alentejana (AL) y de genotipo convencional [(Large-White × Landrace (LL)]). Se analizaron muestras de sangre y canal (12 de cada genotipo) de un total de 34 camadas (18 AL y 16 LL). Las cerdas AL presentaron gestaciones 4 días más cortas que las cerdas LL. Cuando se ajustaron para el peso al nacimiento, las canales de los lechones AL presentaron mayores porcentajes de materia seca (

Studies on growth rates in pigs and the effect of birth weight

End of project reportThe purpose of this study was to assess some environmental and management factors that affect growth performance on commercial pig units. In experiment 1, a survey was carried out on 22 pig units of known growth performance in south-west Ireland to compare management factors between those showing poor and good growth rates. Low growth rate appears to be due to the cumulative effect of a combination of factors. Experiment 2 was conducted to determine the effects of providing an additional feeder on performance of weaned piglets. No benefits were recorded. Feed consumed from the additional feeder was a replacement for feed that otherwise would have been consumed from the control hopper feeder. Experiment 3 was designed to determine if pig performance and efficiency of growth were affected by weight at birth and at weaning. Lightweight pigs showed inferior growth performance up to the finisher period. Although they compensated some of the inferior growth towards the time of slaughter, they never reached the weights of the heavy birth-weight animals. Males were either significantly heavier or tended to be heavier than females throughout. There was no significant difference between the sexes in the number of days to slaughter. Light and heavy pigs did not differ in the levels of IGF-1 in their blood plasma; however lightweight pigs had significantly lower IgG preweaning. Experiment 4 aimed to determine whether piglet birth weight influenced growth performance, plasma IGF-1 concentrations and muscle fibre characteristics at day 42 of life. At slaughter (Day 42) light birth weight pigs were significantly (P < 0.001) lighter. Plasma IGF-1 concentration was lower by 28% (P=0.06) in light pigs. Muscle fibre cross sectional area and total fibre number were not significantly different between groups. This study should be repeated with bigger numbers

Colostrum production of Alentejano and Large-White × Landrace sows: consumption, passive immunity and mortality of piglets

Colostrum production and composition of 45 Alentejano (AL) and 45 crossed (Large–White × Landrace, LL) sows together with consumption and passive immunization of piglets, were evaluated. Piglets were weighed at birth, 24h, and 21 and 28 days of age. Colostrum was collected, chemically analysed and immunoglobulin G (IgG) determined. On piglets, serum IgG concentrations were determined at 2d and 28d of age. Alentejano piglets consumed 19% less colostrum than LL piglets (267 vs 328 g; p&lt;0.001), but when adjusted for birth weight, the difference between genotypes was not significant (p=0.891). Alentejano sows produced less colostrum (1985±139 g vs 3761±139 g, p&lt;0.001) than LL sows, even after adjustment for litter birth weight. IgG concentrations were higher in AL colostrum at 12 h and 36 h after the onset of farrowing. They were higher in AL than in LL piglets (p=0.025) and higher at 2d than at 28d of age (p&lt;0.001). Mortality rate of piglets until d21 post–farrowing was higher in AL genotype (27% vs 16.1%, p&lt;0.001). In both genotypes main factors influencing piglet mortality were birth weight and colostrum intake (g/kg birth weight). Higher mortality in AL than in LL genotype was attributable to the higher proportion (28.7% vs 11.6%, p&lt;0.001) of light piglets. It is concluded that for similar birth weight, both AL and LL piglets have a similar ability to ingest colostrum and that AL sows are less able to produce colostrum than LL sows. IgG concentrations of colostrum and of piglets serum were higher in AL than in LL genotype

Dietary supplementation with hydrolyzed yeast and its effect on the performance, intestinal microbiota, and immune response of weaned piglets.

The objective of this study was to evaluate the effects of autolyzed yeast on performance, cecal microbiota, and leukogram of weaned piglets. A total of 96 piglets of commercial line weaned at 21-day-old were used. The experimental design was a randomized block design with four treatments (diets containing 0.0%, 0.3%, 0.6%, and 0.9% autolyzed yeast), eight replicates, and three animals per pen in order to evaluate daily weight gain, daily feed intake, and feed conversion in periods of 0 to 15, 0 to 26, and 0 to 36 days. Quadratic effects of autolyzed yeast inclusion were observed on the feed conversion from 0 to 15 days, on daily weight gain from 0 to 15 days, 0 to 26 days and, 0 to 36 days, indicating an autolyzed yeast optimal inclusion level between 0.4% and 0.5%. No effect from autolyzed yeast addition was observed on piglet daily feed intake, cecal microbiota, and leukogram; however, i.m. application of E. coli lipopolysaccharide reduced the values of total leukocytes and their fractions (neutrophils, eosinophils, lymphocytes, monocytes, and rods). Therefore, autolyzed yeast when provided at levels between 0.4% and 0.5% improved weaned piglets’ performance.info:eu-repo/semantics/publishedVersio

Global Effects of Catecholamines on Actinobacillus pleuropneumoniae Gene Expression

Bacteria can use mammalian hormones to modulate pathogenic processes that play essential roles in disease development. Actinobacillus pleuropneumoniae is an important porcine respiratory pathogen causing great economic losses in the pig industry globally. Stress is known to contribute to the outcome of A. pleuropneumoniae infection. To test whether A. pleuropneumoniae could respond to stress hormone catecholamines, gene expression profiles after epinephrine (Epi) and norepinephrine (NE) treatment were compared with those from untreated bacteria. The microarray results showed that 158 and 105 genes were differentially expressed in the presence of Epi and NE, respectively. These genes were assigned to various functional categories including many virulence factors. Only 18 genes were regulated by both hormones. These genes included apxIA (the ApxI toxin structural gene), pgaB (involved in biofilm formation), APL_0443 (an autotransporter adhesin) and genes encoding potential hormone receptors such as tyrP2, the ygiY-ygiX (qseC-qseB) operon and narQ-narP (involved in nitrate metabolism). Further investigations demonstrated that cytotoxic activity was enhanced by Epi but repressed by NE in accordance with apxIA gene expression changes. Biofilm formation was not affected by either of the two hormones despite pgaB expression being affected. Adhesion to host cells was induced by NE but not by Epi, suggesting that the hormones affect other putative adhesins in addition to APL_0443. This study revealed that A. pleuropneumoniae gene expression, including those encoding virulence factors, was altered in response to both catecholamines. The differential regulation of A. pleuropneumoniae gene expression by the two hormones suggests that this pathogen may have multiple responsive systems for the two catecholamines