No abstract

The aim of this study was to evaluate the effect of oregano essential oil (MOO) from Mexican oregano, Lippia berlandieri Schauer, as substitute for Mexican oregano powder (MOP) on pork chorizo physicochemical characteristics, texture, antioxidant capacity, aerobic bacteria colony counts, and sensory evaluation under storage conditions over 7 d. The treatments were T1 = chorizo + 0.1% MOP and T2 = chorizo + 0.1% MOO. The pH, redness (a*), yellowness (b*), Chroma, and browning index (BI) were affected by treatments and storage time. T2 presented lower pH (5.27) at d 1 than at d 7 (5.34), as well as a* (23.13 vs. 25.27), b* (14.85 vs. 17.45), Chroma (28.60 vs. 30.79), and BI (103.42 vs. 109.82) were higher at d 7. At d 1, hardness (1392.75 vs. 872.29 g), springiness (0.3675 vs. 0.3351 mm), gumminess (491.45 vs. 284.38 g), and chewiness (180.25 vs. 95.43 g mm) were higher in T1 than T2. Aerobic bacteria counts (T1—4.19 vs. 4.73 log CFU/g and T2—4.37 vs. 4.50 log CFU/g, respectively) increased within each treatment at d 7. Antioxidant capacity was not affected (26.48 and 27.42%). Oregano odor was different at 7 d with T2 having a stronger odor (5.70) than T1 with oregano powder (4.63). Mexican oregano essential oil in the pork chorizo formulation improved pH, color parameters, textural profile, and sensory characteristics.

-The current study was conducted to investigate the effects of Mexican oregano essential oil (MOO) extracts from Lippia berlandieri Schauer (LBS) and Poliomintha longiflora Gray (PLG) on performance, blood profiles, carcass variables, and meat composition of broilers at slaugther. A total of 360 one-day-old Ross broilers were randomly distributed into four dietary treatments with six replicate pens per treatment and 15 birds per pen. The dietary treatments were: a basal diet (control), control + 0.40 g of LBS/kg of feed, control + 0.40 g of PLG/kg, and control + 0.40 g of LBS/kg + 0.40 g of PLG/kg. Results showed that linear, quadratic, and cubic effects of days were significant in the performance variables of broilers. The treatments with LBS and PLG maintained the broiler body weight without increasing feed intake and water intake when compared with the control group. Broilers given LBS+PLG and PLG had increased blood leukocytes, lymphocytes, lowdensity lipoprotein, and hot carcass yields. In meat composition, treatments with PLG and LBS+PLG presented similar breast protein content compared with the control treatment. Supplementation with these two MOO exhibits positive effects on broiler performance, blood profiles, carcass traits, and meat composition. These two MOO may be promising feed supplements as growth promoters and enhancers of meat quality in broiler production.

The objective of this study was to evaluate the effects of 2 Mexican oregano essential oils (MOO), from Poliomintha longiflora Gray ( PLG ) and Lippia berlandieri Schauer ( LBS ), in drinking water ( DWt ) on the performance, slaughter variables, and meat quality of broilers over a 40 D period of growth. A total of 180 non-sexed Ross-308 broilers (1-day-old) were randomly assigned to 3 treatments with 6 replications each (10 birds per replicate): CON = DWt control (without MOO); PLG = DWt + 400 mg/L of PLG; and LBS = DWt + 400 mg/L of LBS. The CON, PLG, and LBS broilers body weights were similar ( P > 0.05) at all times. Feed intake ( FI ) was different by treatment ( P < 0.05) at 7 and 28 D, and water intake ( WI ) was different ( P < 0.05) at day 28. The CON treatment was highest ( P < 0.05) at 28 D for FI and WI, whereas LBS was lowest ( P < 0.05). Weight gain ( WG ) for CON, PLG, and LBS broilers was similar ( P > 0.05), although WG for CON was slightly higher. In CON broilers, slaughter weight was highest ( P < 0.05), but thigh yield was lowest ( P < 0.05). The CON and PLG treatments were lower ( P < 0.05) in thigh and leg cooking losses. The PLG treatment presented the highest values ( P < 0.05) for breast-meat redness, saturation index, shear force, odor, taste, and overall sensory acceptability. The LBS was higher ( P < 0.05) for breast-meat shear force, cohesiveness and resilience, but lower ( P < 0.05) for sensory attributes. Mexican oregano essential oils at 400 mg/L can serve as natural alternative additives in DWt to improve broiler production and meat quality.

Oregano essential oils from Lippia berlandieri Schauer (Lb) and Poliomintha longiflora Gray (Pl) were tested against the antioxidant butylated hydroxytoluene (Bht) to evaluate effects on the shelf life of ground beef (GB) over 7 days of storage at 4°C. The treatments were GB1 = GB control, GB2 = GB +100 mg/kg of Bht, GB3 = GB +100 mg/kg of Lb, and GB4 = GB +100 mg/kg of Pl. Lightness, redness, hardness, and springiness showed differences (p < .05) between treatments and days interaction, which serve as indicators of ground beef preserved quality and consumer acceptance. Mesophilic, psychrophilic, and lactic acid bacteria numbers and antioxidant activity showed differences (p < .05) for treatments and days. Sensory attributes showed no differences between treatments. The oregano oils may provide extended shelf life for packaged meat products treated with these natural additives and hence may be used for ground beef preservation.

Caulobacter crescentus is a model organism for the study of asymmetric division and cell type differentiation, as its cell division cycle generates a pair of daughter cells that differ from one another in their morphology and behavior. One of these cells (called stalked) develops a structure that allows it to attach to solid surfaces and is the only one capable of dividing, while the other (called swarmer) develops a flagellum that allows it to move in liquid media and divides only after differentiating into a stalked cell type. Although many genes, proteins, and other molecules involved in the asymmetric division exhibited by C. crescentus have been discovered and characterized for several decades, it remains as a challenging task to understand how cell properties arise from the high number of interactions between these molecular components. This chapter describes a modeling approach based on the Boolean logic framework that provides a means for the integration of knowledge and study of the emergence of asymmetric division. The text illustrates how the simulation of simple logic models gives valuable insight into the dynamic behavior of the regulatory and signaling networks driving the emergence of the phenotypes exhibited by C. crescentus. These models provide useful tools for the characterization and analysis of other complex biological networks.

This is the first confirmed report of Encephalitozoon cuniculi (E. cuniculi) in farm meat rabbits located in Northern Mexico. Eighty young rabbits exhibited clinical signs of this zoonotic emerging disease, like torticollis, ataxia, paresis, circling, and rolling. Samples of brain, kidney, and liver were examined for histology lesions. For the first time the lesions caused by E. cuniculi were graded according to their severity (I, II, and III) and the size of the granulomas (Types A, B, and C). The main cerebral injuries were Grade III, coinciding with the presence of Type C granulomas. The cerebral lesions were located in the cortex, brain stem, and medulla. The renal lesions were also Grade III distributed throughout cortex and renal medulla, with no granuloma formation. The involvement of hypersensitivity Types III and IV is suggested. All of the rabbits were seropositive to E. cuniculi by CIA testing, suggesting that this zoonotic and emerging pathogen is widely distributed among animals intended for human consumption. We believe this work could be used as a guide when examining E. cuniculi and will provide direction to confirm the diagnosis of this pathogen.

The effect of sorghum hydrolysed by Trametes maxima CU1 and Pycnoporus sanguineus CS2 was evaluated on growth performance traits and rabbit meat quality. A total of 24 unsexed New Zealand rabbits, weaned at 20 d of age, were allocated to 2 treatments: T1 (diet including 300 g/kg of non-hydrolysed sorghum) and T2 (diet including 300 g/kg of hydrolysed sorghum by Trametes maxima CU1 and Pycnoporus sanguineus CS2). Rabbits of group T2 did not have significantly different (P>0.05) feed intake compared to those in T1. Carcass traits were also not significantly different (P>0.05) between the 2 groups. The pH, water-holding capacity, colour and cooking loss of the longissimus lumborum were not different (P>0.05) between treatments, whereas the pH of the rabbits biceps femoris was higher in T2 (6.21; P<0.05) than in T1 (6.14). Meat hardness and gumminess in T2 were lower (P<0.05) in comparison to meat from T1. Thus, sorghum hydrolysed by Trametes maxima CU1 and Pycnoporus sanguineus CS2 contributed to a better rabbit meat texture.