In no antibiotics ever ( NAE ) broilers, enteric diseases pose a threat to intestinal health and generally welfare, which can be exacerbated because of stocking density. Through knowledge of litter condition and management, disease can be minimized, and broiler welfare can be improved. To evaluate how stocking density influences NAE broilers raised in conventional housing, we evaluated production traits for broilers raised at two stocking densities within a single commercial house. Over the course of 4 flocks, 78,960 Cobb 500 broilers were raised in an industry-style tunnel ventilated house. The house was divided into four equally sized pens, each representing one of two stocking densities. An industry standard stocking density ( SSD ; 0.23 m 2 per bird) and low stocking density ( LSD ; 0.27 m 2 per bird) were each assigned to two pens per flock and were alternated for each subsequent flock raised. Litter moisture content, body weight, mortality, and feed conversion ( FCR ) were evaluated and averaged over all four flocks for both stocking densities. Data were analyzed in JMP with an ANOVA, and means were separated by Tukey's honestly significant difference. As expected, the litter moisture content was significantly larger in the more densely packed SSD pens at weeks 2, 3, 4, and 6, totaling 0.242 moisture content on average at week 6 vs. 0.217 in LSD pens at the same flock age ( P = 0.035). Weekly body weight and final flock FCR were not significantly impacted by stocking density. No association was observed in mortality between the broilers raised in SSD and LSD. The results from this study indicate that the two densities examined were comparable in their growth and efficiency. Additional management pressure would exist to handle the increase in litter moisture in flocks placed at SSD in a production setting; although, raised in the same barn at the same time, the impact of SSD vs. LSD was minimal in this study.
This study compared the quality variation and thermal inactivation of Escherichia coli O157:H7 in non-intact beef and veal. Coarse ground beef and veal patties (2.1 cm thick, 12.4 cm diameter, 180 g) inoculated with E. coli O157:H7, aerobically stored before double pan-broiling for 0–360 s without rest or to 55, 62.5, 71.1, and 76 °C (internal temperature) with 0.5- or 3.5-min rest. Microbial population and qualities including color, cooking losses, pH, water activity, fat, and moisture content, were tested. After cooking the beef and veal patties, the weight losses were 17.83–29%, the pH increased from 5.53–5.60 to 5.74–6.09, the moisture content decreased from 70.53–76.02% to 62.60–67.07%, and the fat content increased (p < 0.05) from 2.19–6.46% to 2.92–9.45%. Cooking beef and veal samples with increasing internal temperatures decreased a* and b* values and increased the L* value. Escherichia coli O157:H7 was more sensitive to heat in veal compared to beef with shorter D-value and “shoulder” time. Cooking to 71.1 and 76 °C reduced E. coli O157:H7 by >6 log CFU/g regardless of rest time. Cooking to 55 °C and 62.5 °C with a 3.5-min rest achieved an additional 1–3 log CFU/g reduction compared to the 0.5-min rest. Results should be useful for developing risk assessment of non-intact beef and veal products.
Lamb was sourced from 3 countries [Australia (AUS), New Zealand (NZ), and United States (US)] representing 2 muscle types (semimembranosus and longissimus lumborum) to evaluate the palatability of lamb loin and leg chops according to US consumers (n = 360). For tenderness, flavor, and overall liking, there was an interaction detected between source country and muscle (P < 0.05). Overall, US loin chops had the highest (P < 0.05) consumer sensory scores, were rated the most acceptable (P < 0.05), and were placed in better than everyday quality or premium quality categories more often than all other treatments. Leg samples sourced from AUS and NZ were rated the lowest (P < 0.05) for consumer sensory scores for tenderness, flavor liking and overall liking, as well as being the least acceptable (P < 0.05) for flavor liking and overall liking. Both source country and muscle impacted (P < 0.01) juiciness scores, as well as tenderness and juiciness acceptability. US chops were juicier and more acceptable for tenderness and juiciness than chops sourced from AUS or NZ, regardless of muscle; consumers rated loin chops juicier and more acceptable for tenderness and juiciness than legs chops, regardless of source country (P < 0.05). Overall, consumers detected differences in palatability between muscle type and the source country. Loin chops were preferred over leg chops for all palatability traits. US consumers preferred the domestically sourced lamb over the lamb sourced from AUS and NZ; however, complete animal background (diet, gender, and age) and knowledge of potential differences in slaughter and chilling conditions, as well as control over postmortem aging, is needed to help differentiate if differences in flavor were due to diet, genetics, or other environmental factors.
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