Associations of acute phase protein levels with growth performance and with selection for growth performance in Large White pigs

Since decades, production traits such as growth rate, feed efficiency or body composition have been drastically increased in pigs by genetic selection. Whether this selection impacted animal robustness is still unclear. In this study, we compared Large White (LW) pigs, a breed submitted to intense genetic selection for production traits, and Basque (B) pigs, a local rustic breed, reared in two different housing environments (conventionalv.enriched). Adaptation to housing conditions among each breed was evaluated at the level of endocrine and immune traits. These are known to be impacted by housing conditions and breed; however, the interaction effects between genotype and environment are less described. Animals (20 per breed and housing environment) entered the experiment at 35 kg of live weight. Levels of cortisol, acute-phase inflammatory proteins, immunoglobulins and hydrogen peroxide, blood formula, lymphocyte proliferation andin-vitrocytokine expression were measured at ∼115 kg of live weight. Animals were checked for skin injuries during the growing period. At slaughter, at the average live weight of 145 kg, carcasses were examined for pathological conditions of the respiratory tract. The major result was that the two breeds exhibited differences in response to the housing environment. Among the 24 sanitary, endocrine or immune traits investigated, the housing conditions affected eight variables in both breeds (salivary cortisol at 0700 and 1900 h, severity of pneumonia at slaughter) or only in B pigs (severe skin lesions) or LW pigs (salivary cortisol at 1500 h, granulocyte numbers and lymphocyte/granulocyte ratio and lymphocyte proliferation). These observations strengthen the hypothesis that selection for high meat production level might be associated with an increased susceptibility of animals to environmental stressors.

Section: Discussionsupporting

confidence: 93%

Section: Introductionmentioning

confidence: 99%

Health and immune traits of Basque and Large White pigs housed in a conventional or enriched environment

Merlot

Vincent

Thomas

et al. 2012

“…An alternative way of diagnosing infection status is to measure APP that are released in response to infection, and elevated APP levels have been associated with both clinical infections and, in apparently healthy pigs, sub-clinical infections (Petersen et al, 2002). We have previously demonstrated negative phenotypic correlations between APP and performance (Clapperton et al, 2005b). Therefore, we are currently generating data to investigate genetic relationships Clapperton, Glass and Bishop of APP levels with performance, in an attempt to further address this issue.…”

Section: Discussionmentioning

confidence: 99%

Pig peripheral blood mononuclear leucocyte subsets are heritable and genetically correlated with performance

Clapperton

Glass

Bishop

2008

Self Cite

Indicator traits used to select pigs for increased resistance to infection or improved health must be heritable and, preferably, be associated with improved performance. We estimated the heritability of a range of immune traits and their genetic and phenotypic correlations with growth performance. We measured immune traits on 589 pigs and performance on 1941 pigs from six farms, three of which were classified as 'high health status' (i.e. specific pathogen-free) and three were of lower health status. All pigs were apparently healthy. Immune traits were total white blood cells (WBC), and peripheral blood mononuclear leucocyte (PBML) subsets positive for CD4, CD8a, gamma delta (gd) T cell receptor, CD11R1 (natural killer cell marker), B cell and monocyte markers at the start and the end of standard growth performance tests. At both time points, all immune traits were moderately to highly heritable except for CD8a 1 cells. At end of test, heritability estimates (h 2 ) (6s.e.) were 0.18 (60.11) for total WBC count. For PBML subset proportions, the heritabilities were 0.52 (60.14) for gd TCR 1 cells, 0.62 (60.14) for CD4 1 cells, 0.44 (60.14) for CD11R1 1 cells, 0.58 (60.14) for B cells and 0.59 (60.14) for monocytes. Farm health status affected the heritabilities for WBC, being substantially higher on lower health status farms, but did not have consistent effects on heritabilities for the PBML subsets. There were significant negative genetic correlations between numbers and proportions of various PBML subsets and performance, at both start and end of test. In particular, the proportion of PBML cells that were CD11R1 1 cells, at end of test, was strongly correlated with daily gain (r g 5 20.72; P , 0.01). There were also weaker but significant negative phenotypic correlations between PBML subsets measured at end of test and performance, for gd 1 T cells, CD8a 1 , CD11R1 1 cells, B cells or monocytes. Phenotypic correlations with daily gain were generally lower at the start of test than at the end of test. These results show that most of the major pig PBML subsets are heritable, and that systemic levels of several of these PBML subsets are genetically negatively correlated with performance. This approach provides a basis for using immune trait markers when selecting boars that can produce higher-performing progeny.

“…An animal in this state of immunological stress is in negative energy balance, and loses rather than gains weight (Johnson, 1997;Spurlock, 1997). Some studies have found an association between elevated pig APP concentration and decreased weight gain (Eurell et al, 1992;Dritz et al, 1996;Clapperton et al, 2005). In this trial, a wide picture of the APP response was obtained, as the study included the main pig positive APP (Lampreave et al, 1994;Gonzá lez-Ramó n et al, 1995;Heegaard et al, 1998;Hulten et al, 2003) as well as the negative APP Apo A-I (Carpintero et al, 2005) and transthyretin (Campbell et al, 2005).…”

Section: Discussionmentioning

confidence: 99%

Pig acute-phase protein levels after stress induced by changes in the pattern of food administration

Piñeiro¹,

Piñeiro²,

Morales³

et al. 2007

A total of 240 pigs, 74 days old, half boars and half females, were included in a trial designed to assess the effect of the stress caused by changes in the pattern of food administration on the concentration of acute phase proteins (APP) and productive performance parameters. Half of the animals (pigs fed ad libitum, AL group) had free access to feed, while the rest were fed following a disorderly pattern (DIS group), in which animals had alternating periods of free access to feed and periods of no feeding, when food was removed from the feeder. The periods of free access to feed (two daily periods of 2-h duration) were randomly assigned, and varied from day to day. Total feed supplied per day was identical in both groups, and exceeded the minimal amount required for animals of these ages. Pen feed intake, individual body weights and the main positive pig APP pig major acute phase protein (Pig-MAP), haptoglobin, serum amyloid A (SAA), C-reactive protein (CRP), and the negative APP apolipoprotein A-I (ApoA-I) and transtherytin were determined every 2 weeks during the period 76 to 116 days of age. Animals fed ad libitum had better average daily gain (ADG) than DIS animals in the whole experimental period ( P , 0.01) but the differences in ADG were only produced in the two first experimental sub-periods (60 to 74 and 74 to 116 days of age), suggesting that the stress diminished when the animals get used to the DIS feeding. Interestingly differences in ADG between DIS and AL pigs were due to males, whereas no differences were observed between females. The same differences observed for ADG were found for APP. DIS males had higher Pig-MAP concentration than AL males at 74 and 116 days of age, lower ApoA-I concentration at 74 days of age and higher haptoglobin and CRP concentration at 116 days of age ( P , 0.05). The results obtained in this trial show an inverse relationship between weight gain and APP levels, and suggest that APP may be biomarkers for the evaluation of distress and welfare in pigs.