Genetic relationships between meat quality traits and fatty acid composition in Japanese black cattle

Genetic parameters were estimated to investigate the relationships between meat quality traits and fatty acid composition from 11 855 Japanese Black cattle. The meat quality traits included beef marbling score (BMS), beef color score, firmness of beef (FIR), texture of beef (TEX) and beef fat color score (BFS). The data on fatty acid composition included oleic acid and monounsaturated fatty acids (MUFA) contents, the ratio of MUFA to saturated fatty acids (MUS) and the ratio of elongation. The heritability estimates for meat quality traits ranged from moderate (0.30) to high (0.72). The strong genetic correlations between them were useful for simultaneous genetic improvement. In addition, high heritability estimates of fatty acid composition, ranging from 0.60 to 0.63, indicated that they could also be improved genetically. The genetic correlations of fatty acid composition with BMS, FIR and TEX were weak and negative. In contrast, positive and stronger genetic correlations were found between BFS and fatty acid composition, in particular, related to the level of unsaturation (0.77 and 0.79 for MUFA and MUS, respectively). This implies that improving the level of unsaturation makes fat darker (more yellow) and thus requires balancing with BFS.     

Genetic parameters of product quality and hepatic metabolism in fattened mule ducks

Genetic parameters of traits related to hepatic lipid metabolism, carcass composition, and product quality of overfed mule ducks were estimated on both parental lines of this hybrid: the common duck line for the maternal side and the Muscovy line for the paternal side. The originality of the statistical model was to include simultaneously the additive genetic effect of the common ducks and that of the Muscovy ducks, revealing a greater genetic determinism in common than in Muscovy. Plasma metabolic indicators (glucose, triglyceride, and cholesterol contents) were heritable, in particular at the end of the overfeeding period, and heritabilities increased with the overfeeding stage. Carcass composition traits were highly heritable in the common line, with values ranging from 0.15 for liver weight, 0.21 for carcass weight, and 0.25 for abdominal fat weight to 0.32 for breast muscle weight. Heritabilities of technological outputs were greater for the fatty liver (0.19 and 0.08, respectively, on common and Muscovy sides for liver melting rate) than for the pectoralis major muscle (between 0.02 and 0.05 on both parental sides for cooking losses). Fortunately, the processing industry is mainly facing problems in liver quality, such as too high of a melting rate, than in meat quality. The meat quality appraisal criteria (such as texture and cooking losses), usually dependent on pH and the rate of decline of pH, were also very lowly heritable. This study demonstrated that genetic determinism of meat quality and ability of overfeeding is not similar in the common population and in the Muscovy population; traits related to fattening, muscle development, and BW have heritability values from 2 to 4 times greater on the common line than on the Muscovy line, which is relevant for considering different selection strategies.     

半番鸭亲本选育实践

半番鸭生产是福建省养鸭业的优势项目,年生产半番鸭苗1亿只,除台湾和西藏两省外,其鸭苗和嘌蛋遍及大江南北,誉称半番鸭故乡.福建省半番鸭生产历史悠久,清康熙年间就有记载.在长期生产实践中,人们积累了从亲本选育、人工授精、孵化和嘌蛋等一整套经验,为半番鸭生产从传统的二元杂交模式向三元杂交过渡,羽色从黑褐色选育成白羽色创造了条件,为日本和东南亚市场提供了优质半番鸭产品.     

不同维生素E水平对骡鸭肝脏L-FABP mRNA表达量的影响

试验旨在研究不同维生素E水平对骡鸭肝脏L-FABP mRNA表达量的影响。试验选用600只70日龄公骡鸭,随机分为4组:Ⅰ为对照组,Ⅱ、Ⅲ、Ⅳ为试验组,分别在填饲日粮基础上分别添加0、40、90、140 mg/kg的维生素E。预饲期25 d,填饲期13 d。结果表明:填饲结束后,与填饲前相比,肝脏中L-FABP mRNA的相对表达量显著升高(P<0.05);填饲结束后,与对照组相比,Ⅱ、Ⅲ、Ⅳ组肝脏组织中L-FABP mRNA相对表达量显著升高(P<0.05),且Ⅱ组最高。     

Prevalence of Salmonella serotypes in male mule ducks in Belgium

Salmonella species infections of male mule ducks were studied for 32 months in 100 flocks on nine duck farms in Belgium. The prevalence of Salmonella species infections changed significantly over time (P<0.001) with infection rates of 50, 13.4, 6.7, 2.6 and 2.9 per cent, respectively, at the time of arrival on the farm, at three, six and nine weeks of age, and when the ducks left the breeding unit to enter the force-feeding rooms (at 11 or 12 weeks of age). During the study period, 95 strains of Salmonella were isolated, belonging to 11 serotypes. S Indiana (42.1 per cent) and S Regent (36.8 per cent) were the two most common serotypes, whereas S Typhimurium and S Enteritidis were found only once (1.1 per cent). All isolated strains were resistant to at least two antimicrobials, but resistance to more than five antimicrobials was observed in 21.6 per cent of the strains.     

Meat quality,fatty acid composition and sensory evaluation of Cherry Valley,Spent Layer and Crossbred ducks

The aim of this research was to compare meat quality characteristics of Cherry Valley (CV), Spent Layer (SL) and Crossbred (CB) ducks. Meat quality, proximate and fatty acid composition were measured in breast and thigh muscles from CV, SL and CB, as well as sensory evaluation of duck soup made from three breeds. The results showed SL contained a highest percentage of protein but lowest moisture than those of CV and intermediate CB (P < 0.05). The L* and b* value of SL ducks were lowest among three breeds (P < 0.05). The breast of SL had higher water‐holding capacity compared to CV (P < 0.05), although CV was the most tender among the three breeds (P < 0.05). SL had lower contents of saturated fatty acid and higher contents of unsaturated fatty acids with a more acceptable P/S ratio of 0.57 and n‐6/n‐3 ratio of 1.52 (P < 0.05). Intramuscular fat and polyunsaturated fatty acids were involved in producing intense aroma and flavor of duck meats. Differences of color and tenderness in meats were attributed to values of L* and cooking loss of muscles. In conclusion, it would be suggested that SL was more suitable for producing duck soup among the three breeds.     

Force-feeding procedure and physiological indicators of stress in male mule ducks.

1. The effects of the force-feeding procedure and its different components on various physiological indicators of acute and chronic stress were investigated in male mule ducks before and during a 12-d cramming period. 2. The highest concentration of corticosterone were measured after injection of ACTH agonist, during the pre-experimental period when the ducks were still housed in collective floor pens and at the time of transfer. 3. During the cramming period, corticosterone measured before and after force-feeding did not differ significantly though there was a non-significant trend towards an increase in certain cases. 4. The different components of force-feeding, including manipulation, intubation, force-feeding with a standard or a large amount of food had no significant effect upon corticosterone concentrations. 5. There was no indication from ACTH agonist challenge either of a change in adrenal sensitivity or a change in its responsiveness. 6. The heterocyte-lymphocyte ratio measured before and at the end of the cramming period did not differ significantly. 7. In conclusion, we observed no significant indication that force-feeding is perceived as an acute or chronic stress by male mule ducks, in our experimental conditions. Nevertheless, it remains to be shown that their adrenocorticotropic axis is responsive to acute stressors.     

脂肪肝鸭重要实质器官病理损伤观察

对8只脂肪肝综合征病鸭的重要内脏器官进行病理学观察。结果表明,病鸭肝脏明显肿大,色黄,质脆易碎,切面色黄、结构模糊、有明显油腻感,有的还有程度不等的瘀血、出血,表面和切面可见散在点状或斑状出血,严重时肝脏边缘部有较大范围出血。镜检发现,肝细胞普遍脂肪变性,胞浆内有数量不等的脂肪小滴,甚至整个细胞为脂肪充满,细胞核被挤压到一侧,严重者导致肝细胞坏死,肝小叶及周围有程度不等的出血。除肝脏外,其他实质器官也有程度不等变性、坏死等病变。     

Estimation of relationships between mineral concentration and fatty acid composition of longissimus muscle and beef palatability traits

The objective of this study was to determine the influence of beef LM nutrient components on beef palatability traits and evaluate the impact of USDA quality grade on beef palatability. Longissimus muscle samples from related Angus cattle (n = 1,737) were obtained and fabricated into steaks for trained sensory panel, Warner-Bratzler shear force (WBSF), lipid oxidation measured by thiobarbituric acid reactive substances (TBARS), fatty acid, and mineral composition analysis. Pearson phenotypic correlations were obtained by the correlation procedure of SAS. Beef palatability data were analyzed by the GLM procedure of SAS with USDA quality grade as the main effect. Specific mineral concentrations did not demonstrate strong correlations with WBSF or sensory traits (r = -0.14 to 0.16). However, minerals appeared to have a stronger relationship with flavor; all minerals evaluated except Ca and Mn were positively correlated (P < 0.05) with beef flavor. Stearic acid (C18:0), C18:2, C20:4, and PUFA were negatively correlated (P < 0.05) with all 3 panelist tenderness traits (r = -0.09 to -0.22) and were positively correlated (P < 0.05) with WBSF (r = 0.09 to 0.15). The MUFA were positively correlated (P < 0.05) with panelist tenderness ratings (r = 0.07 to 0.10) and negatively associated (P < 0.05) with WBSF (r = -0.11). The strongest correlations with juiciness were negative relationships (P < 0.05) with C18:2, C18:3, C20:4, and PUFA (r = -0.08 to -0.20). Correlations with beef flavor were weak, but the strongest was a positive relationship with MUFA (r = 0.13). Quality grade affected (P < 0.05) WBSF, TBARS, and all trained sensory panel traits, except livery/metallic flavor. As quality grade increased, steaks were more tender (P < 0.05), as evidenced by both WBSF and sensory panel tenderness ratings. Prime steaks were rated juiciest (P < 0.05) by panelists, whereas Select and Low Choice were similarly rated below Top Choice for sustained juiciness. Quality grade influenced (P < 0.05) beef flavor, but not in a linear fashion. Although there were significant correlations, these results indicate tenderness, juiciness, and flavor are not strongly influenced by individual nutrient components in beef LM. Furthermore, the positive linear relationships between USDA quality grade and beef palatability traits suggest quality grade is still one of the most valuable tools available to predict beef tenderness.     

Effects of dietary protein level during rearing period and age at overfeeding on magret and foie gras quality in male mule ducks

The aim of this trial was to study the effects of dietary protein content during the rearing period on the performance of mule ducks, according to age at overfeeding (O). Ducks (n = 612) were divided into four groups differing in the protein content in the diet offered during the starting period (S, 0–20 days; S_l vs. S_h: 150 vs. 175 g/kg crude protein (CP)) and growing‐finishing period (GF; 21–67 or 81 days, depending on age at O; GF_l vs. GF_h: 133 vs. 152 g/kg CP). The relative weight of pectoral muscle was lower when ducks were fed a low protein diet during S (?5%, P < 0.01) or GF period (?6%, P < 0.001) at 68 days and higher in ducks of the S_lGF_h group (+6%; P < 0.05) at 82 days. Both foie gras and magret weights fell when ducks were fed S_l or GF_l (P < 0.05 and < 0.01). Mortality during the O period was higher in ducks fed the S_l diet and overfed at late age (7.4% vs. 0%; P < 0.01). In conclusion, a reduction in the dietary protein supply should be recommended only during the GF period for ducks overfed at a late age.     

Time relationships between oviposition,ovulation and egg formation in khaki campbell ducks

1. Ten‐month‐old Khaki Campbell ducks were killed between 5 min and 15 h after oviposition. Time of oviposition and interval between eggs were recorded prior to killing.

2. Oviposition generally occurred between 04.00 and 06.00 h, 7 to 9 h after the onset of the dark period the previous day. Ninety‐seven percent of eggs were laid by 07.00 h.

3. The mean ± SD time interval between consecutive ovipositions was 24.0 ± 0.3 h, with a range from 23.5 to 24.5 h.

4. It was estimated that ovulation occurred on average 10 min after oviposition, and the ovum spent 15 to 30 min in the infundibulum, 2.5 to 3 h in the magnum, 2 to 2.5 h in the isthmus and 18.6 h in the shell gland.     

Effect of dietary protein quality and essential fatty acids on fatty acid composition in the liver and adipose tissue after rapid weight loss in overweight cats

OBJECTIVE: To examine effects of dietary protein quality (casein [CA] vs corn gluten [CG]) and dietary lipids (corn oil [CO] vs oil blend [OB] rich in long-chain polyunsaturated fatty acids [LCPUFAs]) on fatty acid composition in liver and adipose tissue after weight loss in overweight cats. ANIMALS: 24 ovariohysterectomized adult cats. PROCEDURE: Cats were allowed ad libitum access to a high-quality diet until they weighed 30% more than their ideal body weight. Cats were then randomly assigned to 1 of 4 weight-reduction diets (6 cats/diet) and were fed 25% of maintenance energy requirements per day. Diets consisted of CG-CO, CA-CO, CG-OB, and CA-OB, respectively, and were fed until cats lost weight and returned to their original lean body mass. Liver biopsy specimens and samples of perirenal, subcutaneous, and abdominal fat were obtained and analyzed for fatty acid content. RESULTS: Following weight loss, fatty acid composition of the liver and adipose tissue was primarily affected by protein quality in that cats fed CA had significantly higher percentages of 20:4(n-6) and 22:6(n-3) fatty acids than those fed CG. Cats fed the CG-CO diet had the lowest concentrations of LCPUFAs, suggesting that dietary lipids and protein quality each influence fatty acid composition in tissues. CONCLUSIONS AND CLINICAL RELEVANCE: These data provide direct evidence that dietary protein quality alters fatty acid composition of tissues during weight loss in cats. The fatty acid patterns observed suggest that protein quality may alter fatty acid composition through modulation of desaturase activity.     

Dose-response relationships between porcine somatotropin, muscle composition, muscle fiber characteristics and pork quality

The dose-dependent effects of porcine somatotropin (pST) on cellular aspects of skeletal muscle growth, muscle composition and measures of pork quality were investigated in growing barrows and gilts. Eighty crossbred pigs weighing 46 kg were assigned randomly to receive daily subcutaneous injections of 0, 30, 60, 120 or 200 micrograms pST/kg BW until they weighed 100 kg. Semitendinosus muscle weights were increased with pST dose (linear, P less than .001) by 21%. Percentage of type I and type II muscle fibers was not changed with pST, but cross-sectional area of type I and type II fibers was increased in parallel with muscle weight. Percentage of moisture increased (P less than .01) and percentage of lipid decreased (P less than .01) as pST dose increased. The pH of the longissimus 24 h postmortem increased (P less than .01) .1 to .2 units with increasing pST dose, but subjective evaluation for color, firmness and wateriness of the longissimus indicated no discernible treatment effect. Gardner color difference meter "Rd" and "A" values decreased (P less than .01) with a pST dose of 60 micrograms/kg or more, signifying a slightly darker and less red color, respectively, of the longissimus muscle. Weight loss of loin chops 2.54 cm thick cooked to 71 degrees C (20.3% to 23.7%) and shear force of cores 1.27 cm in diameter (2.89 to 3.76 kg) were not related to pST treatment or dose.(ABSTRACT TRUNCATED AT 250 WORDS)     

短嘴型小鹅瘟病毒的传播途径

以短嘴型小鹅瘟病毒(SB-GPV M15株)分别经消化道(口服),直接接触(同居)和呼吸道(空气传播)等途径人工感染2日龄半番鸭,测定感染后不同时间的试验鸭体质量,喙长宽值,血清LPAI抗体水平和发病死亡程度,探讨短嘴型小鹅瘟病毒不同感染途径对半番鸭致病力的影响。结果显示,口服和同居感染途径均能复制出与野外自然发病一致的症状,感染鸭的体质量和喙长宽值等指标均不同程度低于健康对照组组,且口服感染组的发病程度与感染剂量呈正相关,而呼吸道感染组的体质量和喙长宽值与健康对照组则无明显差异;试验鸭血清抗体测定显示口服和同居感染组的抗GPV LPAI抗体产生期早于空气感染组,且PI 14d抗体全部阳转而空气感染组抗体阳转率仅20%。结果表明,短嘴型小鹅瘟病毒的主要传播途径是消化道和直接接触感染,而空气传播能力则较弱。     

Meat quality and intramuscular fatty acid composition of Catria Horse

In order to extend scientific knowledge on autochthonous Italian equine meat, the physical–chemical parameters of Catria Horse Longissimus thoracis (LT) muscle and its nutritional characteristics have been investigated. Ten steaks of Catria foal raised at pasture and fattened indoors for 2 months were dissected, and LT muscle was analyzed for chemical composition, total iron, drip loss, colorimetric characteristics, intramuscular fat, fatty acid profile and nutritional indexes. Steak dissection showed that LT muscle accounted for 36.78% and fat accounted for 9.19% of weight of steak. Regarding chemical composition, protein and fat content was 20.31% and 2.83%, respectively. Total iron content (1.95 mg/100 g) was lower than data reported in the literature. Color parameters showed a luminous and intense red hue muscle. The sum of unsaturated fatty acid composition (50.3%) was higher than the sum of saturated fatty acids (46.64 %). The fatty acid profile and nutritional values of Catria Horse meat could be modified adopting extensive rearing systems and grazing. The data suggests that further investigation on the composition of Catria Horse meat should be carried out to valorize this autochthonous breed, reared in sustainable livestock systems, and its meat in local short‐chain systems.     

肉鸡脂肪肝综合征血液流变学和生化指标变化的研究

用高脂肪日粮饲喂45日龄三黄肉鸡，建立脂肪肝综合征（fatty liver syndrome, FLS）病理模型，系统观察了FLS鸡血液流变学和生化指标的变化规律。与正常对照鸡比较，FLS鸡全血黏度、血浆黏度、全血高切还原黏度、全血低切还原黏度、全血高切相对指数、全血低切相对指数显著升高（P〈0．01），ESR血沉、血沉方程k值降低（P〈0．01）；血清甘油三酯含量、总胆固醇含量、低密度脂蛋白胆固醇含量、丙氨酸氨基转移酶活性、天门冬氨酸氨基转移酶活性以及肝脂肪含量和肝指数明显升高（P〈0．01）。     

添加动植物性油脂填饲对鸭肥肝性能的差异影响

在骡鸭与樱桃谷鸭的填肥料中添加4%玉米油或鸭油,研究添加动植物油脂填饲对鸭产肝性能的差异影响。结果表明:添加玉米油与添加鸭油填饲相比,两品种鸭于较低的料肝比获得较高的肝重,且骡鸭添加玉米油组的肥肝率显著高于鸭油组(高出30%);经填饲,骡鸭的肥肝重较樱桃谷鸭高,同时料肝比较低,但差异均不显著(P>0.05)。这意味着肥肝生产中,填饲时添加玉米油较添加鸭油更利于提高产肝性能,并且对骡鸭更有效。对于其根本原因,需进一步从分子水平上研究鸭肝的生脂酶基因、与甘油三酯分泌及脂肪分解相关酶基因的表达差异。     

Relation between the biochemical composition of the blood of cows and variations in milk production

A significantly lower alkaline phosphatase activity was recorded in the arterial blood of cows with higher milk efficiency. They also had higher sugar contents in their blood: highly significantly in arterial blood and significantly in venous blood after milking. As to the other blood components, the differences are low and insignificant. A significant positive relationship between the daily milk yield and the content of ash in blood (mainly in venous blood before milking), highly significant positive relationship between protein content in arterial blood and daily milk yield, and significant to highly significant negative relationship between the activity of alkaline phosphatase in arterial and venous blood before milking and the level of gamma-globulins in arterial blood were recorded in the group of cows with higher milk output. In the group of cows with lower milk production, significant to highly significant negative relationships were obtained between protein content in blood and the daily milk yield (in arterial and venous blood before milking).