Environmental impact of heavy pig production in a sample of Italian farms. A cradle to farm-gate analysis.

Four breeding piggeries and eight growing-fattening piggeries were analyzed to estimate potential environmental impacts of heavy pig production (>160kg of live height at slaughtering). Life Cycle Assessment methodology was adopted in the study, considering a system from breeding phase to growing fattening phase. Environmental impacts of breeding phase and growing-fattening phase were accounted separately and then combined to obtain the impacts of heavy pig production. The functional unit was 1kg of live weight gain. Impact categories investigated were global warming (GW), acidification (AC), eutrophication (EU), abiotic depletion (AD), and photochemical ozone formation (PO). The total environmental impact of 1kg of live weight gain was 3.3kg CO2eq, 4.9E-2kg SO2eq, 3.1E-2kg PO4(3-)eq, 3.7E-3kg Sbeq, 1.7E-3kg C2H4eq for GW, AC, EU, AD, and PO respectively. Feed production was the main hotspot in all impact categories. Greenhouse gases responsible for GW were mainly CH4, N2O, and CO2. Ammonia was the most important source of AC, sharing about 90%. Nitrate and NH3 were the main emissions responsible for EU, whereas P and NOx showed minor contributions. Crude oil and natural gas consumption was the main source of AD. A large spectrum of pollutants had a significant impact on PO: they comprised CH4 from manure fermentation, CO2 caused by fossil fuel combustion in agricultural operations and industrial processes, ethane and propene emitted during oil extraction and refining, and hexane used in soybean oil extraction. The farm characteristics that best explained the results were fundamentally connected with performance indicators Farms showed a wide variability of results, meaning that there was wide margin for improving the environmental performance of either breeding or growing-fattening farms. The effectiveness of some mitigation measures was evaluated and the results that could be obtained by their introduction have been presented.

Characterization of protected designation of origin Italian meat products obtained from heavy pigs fed barley-based diets.

A study was conducted to evaluate the quality and sensory properties of protected designation of origin (PDO) Parma ham and Piacentina neck obtained from heavy pigs (Italian Duroc × Italian Large White) fed barley-based diets. Four diets were tested: 1) a corn-based diet (control), 2) the control diet with 80% of a normal-amylose hulled barley variety (Cometa), 3) the control diet with 80% of a normal-amylose hulless barley variety (Astartis), and 4) the control diet with 80% of a low-amylose hulless barley variety (Alamo). All the meat products were analyzed for physicochemical and color parameters. The dry-cured hams and necks were also evaluated for sensory properties. The data of physicochemical, color, and sensory parameters were separately analyzed by multivariate factor analysis, and interpretation of each extracted factor was based on specific original variables loading on each one. The meat products obtained from pigs fed the barley-based diets differed from those obtained from the control pigs on the PUFA factors characterized by C18:2-6 and omega-3:omega-6 ratio. In particular, the meat products obtained from pigs fed the barley-based diets had a lower content of C18:2-6 and a higher omega-3:omega-6 ratio ( < 0.05) than the control. In fresh hams, iodine number and SFA (C16:0 and C18:0) in addition to PUFA and omega-3:omega-6 ratio loaded on the PUFA/SFA factor. The fresh hams produced from pigs fed the barley-based diets had subcutaneous fat (SC) with a lower iodine number and a higher SFA level compared with those produced from the control pigs ( < 0.05). A sex effect was measured for PUFA/SFA and oleic acid factors. In particular, the barrow SC had a lower SFA content, higher PUFA and C18:1-9 levels, and a higher iodine number ( < 0.05) than the gilt SC. There were no appreciable differences in the color and sensory properties of meat products obtained from pigs fed the different diets. The hams from barrows differed from those obtained from gilts on the lean properties factor describing properties related to aspect and odor of dry-cured hams. Indeed, the hams from barrows were depreciated compared with the hams from gilts for minor intensity, brightness, and uniformity of the lean, pinkish intermuscular fat and cured odor. In conclusion, barley could be used as a replacement for corn in heavy pig diets for the production of PDO Italian products without negative effects on the physicochemical, color, or sensory characteristics of meat products.

Performance and fat quality of heavy pigs fed maize differing in linoleic acid content.

Maize shows wide differences in linoleic acid due both to total lipid content and to fatty acid profile. Therefore, diets containing the same high maize percentage (up to 55%) can differ in linoleic acid content and lead to subcutaneous fats of differing suitability for raw ham curing. Two trials were performed on heavy pigs; in the first, 60 pigs (body weight 48.7+/-5.1 kg) were fed three diets made using three maize batches differing in linoleic acid due to different total lipid content, in the second trial, 40 pigs (live weight 70.4+/-3.4 kg) were fed two diets made using two maize batches differing in linoleic acid due to their fatty acid profile. Pigs were slaughtered at 170 kg of live weight. In both trials, the growth and slaughtering performance did not differ. In the first trial the three diets lead to a different content of linoleic acid both in subcutaneous (low linoleic vs medium linoleic vs high linoleic P0.01) and intramuscular fat (low linoleic vs high linoleic P0.05). In the second trial different linoleic acid content was observed for subcutaneous fat (P0.01) but not for intramuscular fat. To formulate diets for heavy pigs, it is crucial to know the linoleic acid content of the maize used, because differences of only 0.3% can lead to significant differences in fatty acids composition of depot fats.

Use of pure glycerol in fattening heavy pigs.

Eighty Italian Duroc×Italian Large White pigs (BW 42.6±3.37kg) were used to determine the effects of pure glycerol on growth performance and meat quality of heavy pigs. Pigs were divided into five groups receiving 0% (control), 5% or 10% during the growing and finishing phases (42.6-160kg BW) (G+F5,G+F10) or 5% or 10% during the finishing period (100-160kg BW) (FIN5,FIN10) of pure glycerol in substitution for maize meal (on a dry matter basis). The pigs were slaughtered at approximately 160kg BW. The growth performance of pigs fed 5% glycerol did not differ from controls regardless of feeding duration, whereas those fed 10% glycerol showed reduced growth and poorer feed:gain ratio. Fat quality and meat suitability for raw ham curing were not affected by dietary treatment. Differences were not consistent enough to draw any conclusion about the effects of feeding glycerol on sensory characteristics.

Effect of feeding partially hydrogenated lard on trans-fatty acid content of muscle and backfat of heavy pigs.

The incorporation of fat in diets for heavy pigs may be necessary in order to increase their energy intake in the finishing period. Lard may be a good lipid source but it contains 10-13% of linoleic acid, which makes the subcutaneous fat less suitable for long term curing of raw ham. Partial hydrogenation of lard decreases linoleic acid content, but increases trans-fatty acid content. This trial involved two groups of pigs of 114kg live weight, fed for the last two months before slaughter with diets containing 3% lard (L) or 3% partially hydrogenated lard (PHL). The PHL contained about 10% trans-fatty acids and 2.5% linoleic acid. Rearing performance and carcass characteristics were unaffected by treatment. The group fed PHL showed a lower percentage of linoleic acid in the backfat (PHL 12.28% vs. L 13.04%) and a higher percentage of C18:1 trans-fatty acids both in backfat (0.5% vs. 0.06%) and in intramuscular fat (0.2% vs. 0.04%).

Effect of age at slaughter on carcass traits and meat quality of Italian heavy pigs.

Barrows and gilts (n = 128) from four breed crosses were used to investigate the effect of age at slaughter on carcass traits, proteolytic enzyme activity, and meat and fat quality. Pigs were blocked by breed cross into four blocks, and within blocks, one pen (eight barrows and eight gilts) was assigned randomly to be slaughtered at either 8 or 10 mo of age. Pigs were fed a corn-barley-soybean meal finisher diet from 104 +/- 2.5 d of age (37.7 +/- 0.33 kg BW) to the appropriate slaughter age. Carcasses from older (10 mo) pigs had lower (P < 0.01) muscularity indexes and lean cut yields than those of younger (8 mo) pigs, but dressing percentage and longissimus muscle area increased (P < 0.01) with age. Older pigs produced a redder (P < 0.01) and darker (P < 0.05) semimembranosus, with lower (P < 0.01) ultimate pH and cathepsin B and B + L activities, as well as higher (P < 0.01) aminopeptidase hydrolyzing activity than younger pigs. Moreover, the longissimus muscle of pigs slaughtered at 10 mo of age had lower (P < 0.01) drip and cooking loss percentages than that from pigs slaughtered at 8 mo of age. Ham subcutaneous fat from 10-mo-old pigs had greater (P < 0.05) percentages of oleic acid and lower (P < 0.01) proportions of moisture, linoleic, and linolenic acids than subcutaneous fat from pigs slaughtered at 8 mo of age. Results from this study indicate that fresh hams from pigs slaughtered at 10 mo of age would be more suitable for the production of high-quality, Italian, dry-cured hams.