Use of the spectrophotometric color method for the determination of the age of skin lesions on the pig carcass and its relationship with gene expression and histological and histochemical parameters.

The presence of lesions on the pig carcass is an indicator of poor animal welfare and has economic impact as it downgrades the carcass value. The assessment of the age of lesions on the carcass may help identify risk factors and ultimately prevent their occurrence. The aim of this study was to assess the age of lesions on pig carcasses through spectrophotometric color evaluation and to relate the results with gene expression and histological and histochemical parameters. A total of 96 barrows were mixed 4 times over 3 d before slaughter and 80 lesions were selected after skin lesion observations to define 4 age categories: < 7 h (T1), 7-25 h (T2), 25-30 h (T3), and 49-54 h (T4). A nonlesioned skin area was used as a control. At slaughter, 3 biopsies per lesion and control skin were taken immediately after bleeding for analyses of gene expression (, , , , , , , , , ), skin histological characteristics (inflammation, erosion or ulceration, and necrosis), and enzyme activity (alkaline phosphatase and adenosine triphosphatase). The number of lesions was counted on each carcass, and the color was assessed visually by a pictorial chart and instrumentally through a spectrophotometer. Delta values (Δ) were calculated as the difference between the value of the lesion and the value of the control for all measures, except for the histological analysis. Results indicated that visual color observation was not sufficiently accurate to discriminate lesions by time of infliction ( > 0.10), while the spectrophotometer ΔL* and Δa* values variation allowed the identification of < 7 h or > 25 h old lesions ( < 0.05). Similarly, the expression of , , , , and genes was higher ( < 0.05) in < 7 h old lesions, while gene expression was higher ( < 0.05) in < 25 h old lesions. As for the histological analysis, the severity of inflammation was correlated with the age of the lesion (lower score in < 7 h old lesions and higher score in > 25 h old lesions; < 0.05). To conclude, the spectrophotometric color assessment of the carcass lesions at slaughter appears to be a reliable method to discriminate between fresh and older lesions on the carcass at the abattoir.

Growth parameters, behavior, and meat and ham quality of heavy pigs subjected to photoperiods of different duration.

To attain a good level of animal welfare, pigs require a sufficient environmental illumination. Therefore, minimum levels for light duration and light intensity have been set up by the European legislation (Directive 2008/120). An experimental trial was designed to determine whether an increased duration of the photophase (up to 16 h of light per day) could modify the behavior, productive parameters, and meat and ham quality of Italian heavy pigs. Forty crossbred (Large White × Landrace) castrated males pigs (26 kg initial average BW) intended for Protected Designation of Origin (according to European Union Regulation 1151/2012, ) dry-cured ham production were raised according to Parma ham production rules up to the weight of 160 kg. Pigs were homogeneously allotted to 2 experimental groups, each comprising 20 pigs. The short photoperiod (SP) group received the minimum mandatory number of hours of light per day (corresponding to 8 h/d), whereas the long photoperiod (LP) group was subjected 16 h of light per day during the whole production cycle. Light intensity was maintained at 40 lux (i.e., the minimum mandatory level) for both the experimental groups. Growth and slaughtering parameters, carcass traits, fatty acid composition, meat and dry-cured ham quality, and animal behavior were assessed. Pigs in the LP group showed a greater live weight and carcass weight compared to the SP group ( = 0.005 and = 0.007, respectively). Similarly, hams obtained from the LP group were significantly heavier and their weight losses during the dry-curing period were reduced ( < 0.01) when compared to the SP group. No significant differences were detected between the experimental groups as concerns meat and ham quality or fatty acid composition of the subcutaneous fat. Pigs in the LP group spent more time resting and less time pseudo-rooting ( < 0.01). Our results indicate that, given an appropriate dark period for animal rest, an increased duration of the photoperiod, even at the lower mandatory light intensity level, can favorably affect growth parameters of heavy pigs without any negative effect on animal behavior, carcass traits, or meat or long-cured ham quality. Therefore, rearing pigs in semidarkness should be considered as a baseless practice, contrary to animal welfare.

A study on some welfare-related parameters of hDAF transgenic pigs when compared with their conventional close relatives.

Pigs are increasingly used in medical research as transgenic laboratory animals; however, little knowledge is presently available concerning their welfare assessment. The aim of the present study was to investigate some welfare-related parameters of transgenic pigs intended for xenotrasplantation (human decay-accelerating factor (hDAF)) when compared with their conventional (i.e. not transgenic) close relatives (full sibs and half sibs). A total of 14 Large White female transgenic pigs and 10 female non-transgenic (conventional) pigs from four litters were used. All pigs were from the same conventional boar, donor of the semen treated for sperm-mediated gene transfer. During the experiment, BW ranged from 50 to about 80 kg and pigs were weighed at the beginning and at the end of the experiment. Animals were subjected to a set of behavioural tests: a human approach test (HAT), a novel object test (NOT) and an open-door test (ODT). Food preferences were tested through the offer of different foods (banana, apple, carrot, cracker and lemon). During a 4-day period, pigs were diurnally videotaped to study the prevalence of the different behaviours and social interactions (aggressive and non-aggressive interactions). At the end of the trial, cortisol level had been assessed on bristles. No significant differences (P>0.05) were observed between hDAF transgenic and conventional pigs with respect to growth traits, reactivity towards unexpected situations (HAT, NOT, ODT), food preferences, main behavioural traits, social interactions and hair cortisol.

Effects of the rearing season on carcass and meat quality of suckling Apennine light lambs.

The aim of this study was to evaluate the effects of the rearing season (autumn vs winter) on the carcass and meat quality of light lambs, obtained according to the traditional farming system usual in central Italy. Eighty carcasses from 60 d+/-3 old unweaned Apennine single birth male lambs, permanently reared indoor, half in autumn (receiving milk from ewes permanently pastured) and half in winter (which dams did never acceded to pasture), were weighed, classified according to the EU classification system for light lambs, and their Longissimus lumborum meat was analysed for pH, colour, drip and cooking losses, proximate composition and fatty acids profile of intramuscular fat. Most of the carcasses fully responded to the 1st quality EU requirements and no effects of the rearing season was evident on carcass characteristics. On the contrary, L. lumborum of lambs born and reared in autumn, receiving milk from ewes permanently pastured, evidenced a lower Lightness L* (P=0.02), a higher Chroma C* (P=0.01), with a higher fat content (P=0.04) than lambs reared in winter, which dams were permanently stall-fed. Moreover the intramuscular fat of the former was characterized by a greater PUFA concentration (P=0.01), a more favourable n-6/n-3 ratio (P<0.001), and a higher CLA content (P<0.001) than the latter, as a result of the difference related to the sheep traditional feeding system.