Intra-uterine growth retardation (IUGR) impairs postnatal growth and development of the small intestine (SI) in neonatal pigs and infants. L-Arginine (Arg), a critical amino acid involved in promoting growth and metabolism in young mammals, is more deficient in IUGR fetuses. However, little is known whether dietary Arg supplementation would accelerate the impaired development of the SI induced by IUGR in piglets. In the present study, a total of six litters of newborn piglets were used. In each litter, one normal and two IUGR littermates were obtained. Piglets were fed milk-based diets supplemented with 0 (Normal), 0 (IUGR) and 0·60% Arg (IUGR þ Arg) from 7 to 14 d of age, respectively. Compared with Normal piglets at 14 d of age, IUGR decreased (P,0·05) the growth performance, entire SI weight, and villus height in the jejunum and ileum. IUGR piglets had lower (P,0·05) mucosal concentrations of Arg, insulin, insulin growth factor 1, as well as phosphorylated Akt, mammalian target of rapamycin (mTOR) and p70 S6 kinase but higher (P,0·05) enterocyte apoptosis index (AI). After Arg treatment in IUGR piglets, the growth performance, weight of entire SI and mucosa, and villus height in the jejunum and ileum were increased (P,0·05). Diet supplemented with Arg also increased (P,0·05) the levels of Arg, insulin, phosphorylated Akt and mTOR in SI mucosa of IUGR piglets, and decreased (P,0·05) the AI and caspase-3 activity. In conclusion, Arg has a beneficiary effect in improving the impaired SI development in IUGR piglets via regulating cell apoptosis and activating Akt and mTOR signals in SI mucosa.

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Apoptosis is a form of cell death that involves the changes of mitochondrial function and the regulated activation of caspase cascades, which selectively cleave cytoskeleton proteins and catalyze the changes of cell organelles and morphological structure. The changes of mitochondrial function, cell morphological structure, and degradation of cytoskeleton are considered to be responsible for the development of meat qualities. The LM, semitendinosus, and psoas minor (PM) muscles of 5 crossbred bulls were used to observe the morphologic and quantitative changes of apoptosis, as well as the change of caspase-3 activity during 7 d storage. Transmission electron microscopy shows that the typical features of apoptosis appeared in muscles between d 1 and 4. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) positive nuclei were detected at d 4 and increased subsequently. The count of TUNEL-positive nuclei was different in 3 muscles at d 7 (P < 0.001). There was a significant increase in caspase-3 activities at 4 h postmortem relative to the activities at the first 30 min in 3 muscles (P = 0.0147 in LM; P = 0.0058 in PM; P = 0.0306 in semitendinosus), and the apexes had 2.9 to 6.5 times more activities than activities at the first 30 min postmortem. Apoptosis did exist in 3 types of muscles during the conditioning period. Apoptosis and caspase cascades system could be associated with the postmortem development of meat quality in skeletal muscles of bulls.

Four hundred fifty 52-wk-old Lang-shan breeding hens (dual-purpose type, an indigenous poultry breed of China) were randomly divided into 9 treatments with 5 replicates each treatment. They were fed corn-soybean diets with 0, 0.30, and 0.60 mg of Se/kg from Se yeast and 3.2, 4.0, and 5.4 g of dl-Met/kg, respectively. After incubation, 250 chickens each treatment were randomly divided into 5 replicates and fed the same diet. At 21 d old, 10 male chicks in each treatment were slaughtered. There results were as follows. (1) The Se content significantly increased with the increase of Se yeast supplementation (P < 0.01). (2) The carbonyl content of the myofibrillar protein significantly decreased with the increase of Met supplementation (P < 0.01) and the carbonyl content of the 0 mg of Se/kg treatment was higher than the 0.3 mg of Se/kg treatment (P < 0.01). (3) Selenium supplementation at 0.30 and 0.60 mg/kg significantly decreased malondialdehyde content compared with that of 0 mg of Se/kg (P < 0.01) and 4.0 and 5.4 g of Met/kg supplementation significantly decreased malondialdehyde content compared with that of 3.2 g of Met/kg (P < 0.01). (4) Supplementation of Met at 5.4 g/kg significantly increased International Commission on Illumination a* value compared with 3.2 and 4.0 g of Met/kg (P < 0.01). Supplementation of Se at 0.6 mg/kg significantly increased a* value compared 0 and 0.3 mg of Se/kg (P < 0.01) and 0 mg of Se/kg significantly increased b* value compared with 0.30 and 0.60 mg of Se/kg (P < 0.01). (5) Selenium supplemented at 0.30 and 0.60 mg/kg decreased drip loss compared with 0 mg of Se/kg and 4.0 and 5.4 g of Met/kg decreased drip loss compared with 3.2 g of Met/kg, respectively. The conclusion was drawn that Met and Se yeast supplementation of the maternal diets could improve color, water-holding capacity, and oxidative stability of male offspring meat to an extent.

Effects of breed, muscle type, and frozen storage on physico-chemical characteristics of lamb meat and its relationship with tenderness, CyTA -Journal of Food, 14:1, 109-116, DOI: 10.1080/19476337.2015 To link to this article: https://doi.org/10. 1080/19476337.2015 The effects of breed, muscle types, and frozen storage time on the physico-chemical characteristics of the two most important China breeds were considered. Twenty-four lambs of Bashbay and Xinjiang Merino sheep of 7-9 months old were slaughtered, respectively, and frozen for 1, 7, 15, or 30 days. The meat pH, water holding capacity (WHC), intramuscular fat, cooking loss, myofibrillar fragmentation index (MFI), moisture, shear force (SF), and connective tissue were measured at 24 h postmortem. These physico-chemical characteristics varied with breed and muscle types. Xinjiang Merino had a higher pH (P < 0.001) than Bashbay. M. supraspinatus had a higher pH (P < 0.001) compared to the M. gluteus and M. longissimus dorsi. The total and insoluble collagen and intramuscular fat were higher in Xinjiang Merino. As the time of frozen storage increased from 1 to 15 days, the intramuscular fat, cooking loss, WHC, and MFI in Xinjiang Merino increased gradually. SF and tenderness were improved.Keywords: lamb; muscle; freezing; meat quality; tenderness Los efectos de la raza, los tipos de músculos y el tiempo de almacenamiento congelado sobre las características fisicoquímicas de las dos razas más importantes de China fueron considerados. Veinte cuatro corderos de Bashbay y Xinjiang Merino fueron utilizados respectivamente. Los animales fueron sacrificados a una edad aproximada de 7 a 9 meses de edad y la carne fue congelada durante 1,7, 15 o 30 días. El pH de carne, capacidad de retención de agua (WHC), grasa intramuscular, Las perdidas al cocinar, índice de fragmentación miofibrilar (IFM), humedad, fuerza de corte (SF) y tejido conjuntivo fueron medidos en 24 horas post-mortem. Estas características fisicoquímicas variaron con raza y tipos musculares. Xinjiang Merino tuvo un pH mayor (P < 0,001) que bashbay ovejas. M supraspinatus tenía un pH mayor (P < 0,001) en comparación a la M glúteo y M longissimus dorsi. El colágeno total e insoluble y grasa intramuscular fueron superiores en Xinjiang Merino. Como el tiempo de almacenamiento congelado aumentó de 1 dia para 15 dias, la grasa intramuscular, Las perdidas al cocinar, la capacidad de retención de agua y la MFI en Xinjiang Merino aumentaron gradualmente. Fuerza de corte y ternura fue mejorado. Palabras