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1.
Crossbred pigs (n = 240) from Pietrain x Large White sires mated to Landrace x Large White dams, with an average age of 100 d (60.5 +/- 2.3 kg of BW), were used to investigate the effects of sex and slaughter weight (SW) on growth performance and on carcass and meat quality characteristics. There were 6 treatments arranged factorially, with 3 classes (intact females, IF; castrated females, CF; and castrated males, CM) and 2 slaughter weights (114 and 122 kg of BW). Each of the 6 combinations of treatments was replicated 4 times, and the experimental unit was a pen with 10 pigs. Castrated males and CF ate more feed, grew faster, and had more carcass backfat depth and fat thickness at the gluteus medius muscle but lower loin yield than IF (P < 0.05). In addition, CF and CM had more intramuscular fat (P < 0.05) and less linoleic acid content in the subcutaneous fat (P < 0.01) than IF. Pigs slaughtered at 122 kg of BW had lower ADG (P < 0.05), decreased G:F (P < 0.05), and more gluteus medius fat than pigs slaughtered at 114 kg of BW (P < 0.05). It was concluded that CF and CM had similar productive performance and meat quality characteristics when slaughtered at the same age, and that castration of females improved ADG and increased weight and fat content of primal cuts with respect to IF. Therefore, castration of females is recommended in pigs destined for the dry-cured industry because of the beneficial effects on quality of the primal cuts.  相似文献   

2.
This research aimed to determine whether outdoor free-range rearing during the winter (average ambient temperature of 5 degrees C) vs. indoor housing (22 degrees C) affects meat quality, muscle metabolic traits, and muscle fiber characteristics. Forty Large White gilts and barrows were blocked by weight within each gender (20 per gender) and allotted randomly into two groups of pigs, with one reared indoors (IN) in individual pens (2.6 m2) and the other reared outdoors (OUT) from December to March in a 0.92-ha pasture. Both groups had free access to the same grower-finisher diet from 23 to 105 kg. At slaughter, adipose (backfat [BF] and omental fat [OF]) and muscle tissues (longissimus muscle [LM], rectus femoris [RF], and semitendinosus [ST]) were obtained from the right side of each carcass. Muscle fibers were stained and classified on the basis of stain reaction as slow-oxidative (SO), fast oxidative-glycolytic (FOG), and fast glycolytic (FG); fiber area and distribution were determined. Also assessed were carcass characteristics, initial and ultimate pH, L*a*b* values, drip loss percent, glycolytic potential (GP), and intramuscular lipid content, as well as the fatty acid profile of each muscle and adipose tissue. The OUT pigs had lower (P < 0.05) ADG and leaner (P < 0.05) carcasses than IN pigs. Rearing environment did not (P > 0.63) affect the intramuscular lipid content of the ST, but intramuscular lipid content was lower (P < 0.01) in the LM and tended to be higher (P = 0.06) in the RF of OUT than in those of IN pigs. In the BF outer layer of the OUT pigs, the higher PUFA content was compensated by both a lower (P < 0.01) saturated and monounsaturated fatty acid (MUFA) content, whereas in the OF, LM, and dark portion of the ST, only the percentage of MUFA was decreased (P < 0.01). In all tissues of the OUT pigs, the linolenic acid content was higher (P < 0.01) and the n-6:n-3 ratio was lower (P < 0.01). The GP of all muscles was higher (P < 0.01), and the ultimate pH of the RF and ST was lower (P < 0.01), in OUT compared with IN pigs. Lightness (L*) values were lower (P < 0.01) in the LM. Percentages of drip loss were higher (P < 0.05) in the LM and light portion of the ST of OUT than in those of IN pigs. The LM and RF of OUT pigs had more (P < 0.01) FOG and fewer (P < 0.01) FG fibers than muscles of IN pigs. Results suggest that rearing pigs outdoors increases aerobic capacity of glycolytic muscles but has little concomitant influence on meat quality traits.  相似文献   

3.
【目的】探讨豫西黑猪营养成分及肉质性状在不同体重阶段的发育性变化规律。【方法】选取平均体重约为60、75、90、105、120 kg 5个体重阶段的豫西黑猪,每组5头,共25头,每组随机选取3头进行屠宰,公母随机。屠宰后取背最长肌测定眼肌面积、背膘厚、脂肪率、失水率、脂肪酸、氨基酸和胆固醇等指标,测定肌内脂肪含量、脂滴直径和脂滴数目,采集100 g腰大肌测定熟肉率。【结果】豫西黑猪在体重达到120 kg之前,随着屠宰活重的增加,眼肌面积、背膘厚、脂肪率、熟肉率、肌内脂肪含量、肉色、剪切力、脂滴数目和脂滴直径均随之增加。眼肌面积在105、120 kg时均极显著高于60、75 kg(P＜0.01),显著高于90 kg(P＜0.05);背膘厚在90、105、120 kg时均极显著高于60 kg(P＜0.01);肌内脂肪含量在90、105、120 kg时均显著高于60、75 kg(P＜0.05);脂滴直径和脂滴数目在75、90、105、120 kg时均显著高于60 kg(P＜0.05);脂肪酸中饱和脂肪酸以肉豆蔻酸、棕榈酸、硬脂酸等为主,不饱和脂肪酸以棕榈油酸、油酸、亚油酸等为主,氨基酸种类丰富,组氨酸、酪氨酸、缬氨酸和异亮氨酸含量在120 kg时均显著高于105 kg(P＜0.05)。体重与熟肉率、粗蛋白质、肉色、粗脂肪呈极显著或显著正相关(P＜0.01;P＜0.05);肌内脂肪含量与大理石花纹、粗脂肪、肉色、脂滴直径呈极显著或显著正相关(P＜0.01;P＜0.05)。【结论】屠宰活重在120 kg时,豫西黑猪肌内脂肪含量适中,大理石花纹丰富,不饱和脂肪酸与饱和脂肪酸比例适宜,鲜味氨基酸含量增加,胆固醇含量较低,肉色鲜嫩,胴体品质和肉品质最佳。  相似文献   

4.
为研究5-羟色胺（5-HT）受体基因在不同猪种的表达及其与肉质的关系,试验选取淳安花猪与杜长大三元猪各12头,同时饲喂,达上市体重时分别屠宰,测定胴体、肉质性状及肌肉、脂肪中的5-HT受体基因表达量。结果表明：淳安花猪、杜长大三元猪的平均屠宰体重分别为88.1、102.4kg;淳安花猪的板油率、背膘厚、肌内脂肪等指标均显著高于杜长大三元猪（P〈0.05）;屠宰率、眼肌面积杜长大三元猪显著高于淳安花猪（P〈0.05）。5-HT2A、5-HT7受体基因在2个猪种脂肪组织中的表达量均显著高于肌肉组织（P〈0.05）,杜长大三元猪的肌肉中5-HT2A、5-HT7表达量显著低于淳安花猪（P〈0.05）,而脂肪中表达量两猪种间差异不显著。5-HT2A、5-HT7受体基因表达量与屠宰肉质指标之间基本呈负相关,尤其是肌肉中的5-HT2A表达量,呈较强负相关（杜长大三元猪）或显著负相关（淳安花猪）。研究初步认为,5-HT受体基因在中外猪种之间存在表达差异,并与屠宰肉质性状具有相关性。  相似文献   

5.
A total of 196 barrows (88 kg) were used in a 2 x 2 factorial arrangement of treatments and housed in a facility (seven pigs per pen) where temperatures cycled between 27 and 35 degrees C. Treatments consisted of (as-fed basis) two CP levels (13.6 or 11.3%) and two levels of added fat (1 or 8%). Diets were formulated to the same true digestible lysine:ME ratio (1.68 g of lysine/Mcal of ME). Diets were fed and growth variables were measured until pigs reached 114 kg of BW. Ham and LM (loin) 24-h pH (PH24), and light reflectance (CIE L*, and a*, and b*, and hue angle) were taken after slaughter. Additionally, loins were removed and measured for i.m. fat, moisture, glycolytic potential, and subjected to a 7-d retail display evaluation that measured pH, light reflectance, and subjective color and odor score. The remaining boneless lumbar loin segment was vacuum-sealed for 14 d and subsequently measured for pH, light reflectance, and color. Pigs fed the high-CP, low-fat diet had a lower ADG than all other treatments (P = 0.06). High-fat feeding resulted in improved ADG (CP x Fat; P = 0.06) and G:F (Fat effect; P < 0.01). Higher fat and lower protein levels both increased final BF (P = 0.07). Pigs fed the low-CP diets had lower ham PH24 (P < 0.01). Loin PH24 was higher with high fat feeding (P = 0.10). Additionally, pigs fed high fat diets had lower L* values on the ham face and cut loin 24 h after slaughter (Fat effect; P 相似文献   

6.
营养水平对DLY杂交猪肉质性状及H-FABP基因表达的影响   总被引：4，自引：0，他引：4  
将24头起始重为(64.24±2.66)kg的健康DLY杂交猪随机分为2个处理,分别饲喂高、低营养水平的日粮,研究高、低营养水平对育肥猪肉质性状及H-FABP基因表达的影响。结果表明:与低营养水平相比,高营养水平提高了日增重(P=0.273)和饲料报酬(P=0.001);降低营养水平可提高H-FABP基因表达量(P=0.288)和IMF含量(P=0.09),增加肉的嫩度(P=0.026);降低营养水平,还提高了肌肉组织中苹果酸脱氢酶和脂蛋白脂酶的活性(P>0.05)。因此,营养水平可以影响肌肉组织脂肪代谢和H-FABP基因的表达。  相似文献   

7.
This study was designed to investigate the effects of dietary lysine level on the intramuscular fat content of the longissimus in finishing pigs reared at two environmental temperatures. Seventy-two hybrid gilts were individually penned and given ad libitum access to either a diet formulated to meet their lysine requirement (6.4 g/kg lysine) or a lysine-deficient diet (4.8 g/kg). Pigs were held at one of two environmental temperatures (thermoneutral [18 degrees C] or hot [32 degrees C]). The study was carried out between approximately 90 and 126 kg live weight; pigs in the thermoneutral and hot environments were on test for 5 and 7 wk, respectively. There were no interactions between dietary lysine level and environmental temperature. Dietary lysine content did not influence feed intake or average daily gain; however, pigs on the lysine-deficient diet had a poorer gain:feed ratio than those fed to requirement (P < .01). High environmental temperature decreased feed intake (P < .001) and average daily gain (P < .01) but improved gain:feed ratio (P < .01). Backfat at the 10th rib was increased and loin eye area and estimated percentage lean in the carcass were decreased for pigs on the lysine-deficient diet. The higher environmental temperature resulted in an increase in carcass length but had no effect on other carcass measurements or intramuscular fat. Feeding the lysine-deficient diet resulted in an increase of .55 percentage unit in longissimus intramuscular fat content (P < .01); however, there was no difference in subjective marbling scores between the diets. Warner-Bratzler shear force values were not affected by dietary lysine level or environmental temperature. Results from this study suggest that feeding of lysine-deficient diets at the end of the finishing period can increase intramuscular fat deposition under thermoneutral and hot conditions.  相似文献   

8.
In total, 360 pigs slaughtered at 125 kg of BW and destined for the dry-cured industry were used to study the influence of sex and castration [immunocastrated males (IMC), surgically castrated males (CM), and intact females (IF)] in 2 terminal Large White sire lines [Top York (TY) and Tempo (TE)] on growth performance and carcass and meat quality. The female line was Large White × Landrace. The IMC pigs were immunized against gonadotropin-releasing factor (GnRF) with Improvac at 78 (experimental d 16) and 126 (experimental d 64, 48 d before slaughter) d of age. Each of the 6 treatments was replicated 6 times (10 pigs/pen). Through the day of the first Improvac injection (62 to 78 d of age), IMC and IF grew at a slower rate (P < 0.001) than CM with no differences (P = 0.95) in feed intake. The CM had greater G:F than IF, with IMC being intermediate (P < 0.01). From 78 to 126 d of age (between Improvac injections), the IMC pigs ate less feed (P < 0.001) and grew at a slower rate than CM, with IF being intermediate. The IMC pigs were more feed efficient than IF, and both were more efficient than CM (P < 0.001). However, from 126 to 174 d of age (from the second Improvac injection to slaughter), IMC pigs grew at a faster rate (P < 0.001) and were more efficient (P < 0.001) than IF and CM. Overall, IMC and CM pigs grew at a faster rate (P < 0.01) than IF, and IMC were more efficient than the other sexes (P < 0.001), but had reduced (P < 0.001) carcass yield compared with CM and IF. The IMC and IF pigs also had less (P < 0.001) backfat depth than CM. Intact females had greater (P < 0.01) loin yield but less intramuscular fat than IMC and CM and greater (P < 0.05) fresh and trimmed ham yields than CM, with IMC being intermediate. Crossbreds from TE sires grew at a faster rate (P < 0.001) than crossbreds from TY sires, but no differences (P = 0.23 and 0.14, respectively) were found for feed intake or efficiency. Crossbreds from TY produced greater (P < 0.05) fresh and trimmed ham yield, but less (P < 0.01) loin yield and intramuscular fat content than crossbreds from TE. In conclusion, IMC pigs are more efficient, but have less carcass yield than CM and IF. The intramuscular fat content is least for IF and similar for IMC and CM. Crossbreds from TE sires were larger and had greater intramuscular fat content, but slightly less trimmed ham yield compared with crossbreds from TY sires. Immunocastrated pigs can replace CM for the production of heavy pigs destined for the dry-cured industry. Because of increased carcass weight, crossbreds from TE sires may have an advantage over crossbreds from TY sires.  相似文献   

9.
To further understand the germplasm characteristics of Jiangquan Black pig,100 kg Jiangquan Black pigs (10 barrows, 10 sows) and 10 Duroc×Landrace×Yorkshire (DLY) pigs under the same conditions were randomly selected to analyse the slaughter performance and meat quality according to related rules. After slaughtered,the carcass index (carcass weight, loin muscle area, carcass length and backfat thickness etc), meat quality physical indicators (pH, meat color, marbling, drip loss etc), gerneral chemical index (the contents of crude protein, intramuscular fat, moisture and ash etc) and the proportion of amino acids in Jiangquan Black pig were analyzed. The results showed that, Jiangquan Black pig carcass lean meat rate was relatively low, the loin muscle area was reduced by about 30% (P<0.05) compared with DLY pig, while the backfat thickness was higher than that of DLY pig (P<0.05). The meat color, marbling, drip loss, cooking loss, water loss rate index and intramuscular fat content of Jiangquan Black pig were significantly better than that of DLY pigs (P<0.05), the rate of water loss and drip loss and cooking loss were decreased by 4.0%, 3.1% and 2.7%, intramuscular fat content increased by 150.0%. Therefore, The lean yield of Jiangquan Black pig was less than DLY pig, but water retention property, intramuscular fat content, meat color, marbling, meat quality indexes were significantly better than that of DLY pig. In conclusion, Jiangquan Black pig could provide good quality pork for consumers.  相似文献   

10.
A restriction/realimentation feeding strategy was applied to pigs to increase the age at market weight and final ADG, modify protein and lipid deposition rates at carcass and muscle levels, and thereby improve eating quality of the pork. A total of 126 Duroc x (Large White x Landrace) pigs (females and castrated males) were used. At the average BW of 30 kg, within litter and sex, pairs of littermates (blocked by BW) were randomly assigned to ad libitum (AL) feeding during growing (30 to 70 kg of BW) and finishing (70 to 110 kg of BW) periods (AL, n = 56), or restricted feeding at 65% of the ADFI of the AL pigs, on a BW basis, during the growing period and AL feeding during finishing (compensatory growth, CG; n = 56). In each feeding regimen, 15 pigs were slaughtered at 70 kg of BW, and 41 pigs were slaughtered at 110 kg of BW. Additionally, 14 pigs were slaughtered at 30 kg of BW to calculate tissue deposition rates. The CG pigs showed decreased ADG (-35%, P = 0.001) during growing but increased ADG (+13%, P = 0.001) during finishing (i.e., compensatory growth) due to greater (P = 0.001) ADFI and G:F. Hence, CG pigs were 19 d older at 110 kg of BW than AL pigs. The CG pigs were leaner at 70 kg of BW than AL (e.g., 11.7 vs. 13.5 mm of average backfat thickness for CG and AL pigs, respectively, P = 0.023), whereas the differences were reduced at 110 kg of BW (20.6 vs. 21.0 mm of average backfat thickness for CG and AL pigs, respectively, P = 0.536). At 70 kg of BW, intramuscular fat (IMF) content of LM did not differ between CG and AL pigs (1.25 vs. 1.49%, respectively, P = 0.118), whereas CG pigs had less IMF in LM at 110 kg of BW (2.19 vs. 2.53% for CG and AL pigs, respectively, P = 0.034). Feeding regimen influenced the composition of weight gain. From 30 to 70 kg of BW, feed restriction reduced (P = 0.001) lean and adipose tissue deposition at the carcass level and protein and lipid deposition at the muscle level. From 70 to 110 kg of BW, the CG feeding strategy increased (P = 0.016) deposition of adipose but not of lean tissue at the carcass level. However, lipid and protein deposition at the muscle level were not affected. Thus, realimentation promoted deposition of subcutaneous fat over IMF. Feeding regimen hardly affected technological meat quality at 110 kg of BW. The CG feeding strategy decreased (P = 0.014) the meat juiciness score in relation to the decreased IMF but did not influence other sensory traits. Elevated IMF content and improved pork quality might be achieved by modifying the onset or duration of the restriction and realimentation periods.  相似文献   

11.
为了解江泉黑猪的产肉和肉质特性,本试验选取在相同条件下饲养的100 kg左右的江泉黑猪阉公猪、母猪和杜长大三元杂交猪各10头按照相关规定进行屠宰和肉品质测定。对两种猪胴体指标（胴体重、胴体长、眼肌面积、背膘厚等）、肉质的物理指标（pH、肉色、大理石纹、滴水损失等）、常规化学指标（粗蛋白质、肌内脂肪、水分、灰分含量等）及江泉黑猪氨基酸含量进行了测定。结果表明,与杜长大三元杂交猪相比,江泉黑猪胴体瘦肉率较低,眼肌面积降低了30%左右（P<0.05）,而胴体背膘厚较高（P<0.05）。江泉黑猪在肉色、大理石纹、滴水损失、失水率、烹饪损失和肌内脂肪含量等指标上均显著优于杜长大三元杂交猪（P<0.05）,其中滴水损失、失水率和烹饪损失分别降低了约4.0%、3.1%和2.7%,肌内脂肪含量提高了约150.0%。由此可见,江泉黑猪在瘦肉产量上低于杜长大三元杂交猪,但在保水性、肌内脂肪含量、肉色、大理石纹等肉质指标上明显优于杜长大三元杂交猪,可为消费者提供品质优良的猪肉。  相似文献   

12.
To explore the changes in body size indexes,carcass traits and meat quality of Baixi pig×Turok hybrids F1 (DBF1),16 Baixi pigs and 6 DBF1 pigs which were health and 10 months old were chosen for determining the body size indexes,slaughter performance and meat quality. The results showed that there was no significant difference of body size indexes between Baixi pig and DBF1 pigs (P>0.05).The eye muscle area (28.33 cm2),meat color (3.00),marbling (3.50) of DBF1 pigs kept a good level,while the unsaturated fatty acid content (64.33%),the intramuscular fat content (4.08%) and leg to buttock ratio (31.32%) were increased, back fat thickness (24.69%),total flavor amino acid amount (48.46%) were significantly or extremely significantly decreased (P<0.05;P<0.01),and the muscle tenderness,water retention capacity were significantly reduced (P<0.05). In conclusion,the DBF1 pigs could maintain the good meat performance,sensory index and tender degree of muscle,improve the hindquarters meat performance,lean meat and the intramuscular fat contents,but the muscle tenderness,nutritional value, freshness and water retention capacity were declined.  相似文献   

13.
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14.
为探究白洗猪与杜洛克猪杂交后代体尺指标、胴体性状及肉品质变化,本试验选择10月龄健康白洗猪16头、白洗猪×杜洛克猪杂交F1代（DBF1）6头测定其体尺指标、屠宰性能及肉品质性状。结果显示,DBF1猪各项体尺指标与白洗猪相比差异不显著（P>0.05）,眼肌面积（28.33 cm2）、肉色（3.00）、大理石纹（3.50）依然保持在较好水平,不饱和脂肪酸含量（64.33%）、肌内脂肪含量（4.08%）与腿臀比（31.32%）均有所上调,背膘厚（24.69 mm）、鲜味氨基酸总量（48.46%）显著或极显著下降（P<0.05;P<0.01）,肌肉嫩度及保水能力显著降低（P<0.05）。白洗猪与杜洛克猪杂交后,可在保持其良好的产肉性能、较好的肌肉感官指标和肌纤维嫩度等情况下,提高其后躯载肉性能、瘦肉率及氨基酸种类等,但杂交后肌肉嫩度、营养价值、鲜味、保水能力等方面有所下降。  相似文献   

15.
研究测定了25头莱芜猪的胴体品质和肉质特性,分析了莱芜猪胴体、肌肉品质随体重(35、40、50、60、70、80、90kg)的变化规律,为确定不同生长阶段的适宜营养水平和上市屠宰体重提供依据。结果表明,莱芜猪自35~90kg瘦肉率在42.43%~55.29%之间,肌肉pH值稳定在6.19~6.52之间,肉色指标优良,大理石纹评分在2.50~4.38之间,肌内脂肪含量在4.51%~19.92%之间;当70kg体重屠宰时,肌肉失水率较低为13.47%,肉色、大理石纹评分较高分别为3.5、3.38,肌内脂肪含量较高为11.54%。胴体和肉质性状间相关程度有强有弱,相关系数有正有负。相同性状间有较强的正相关,相反性状间有较强的负相关。综合分析试验结果认为,莱芜猪以体重70kg作为上市屠宰体重比较合理。  相似文献   

16.
Inactivated mycobacterium phlei (M. phlei) is well known for its immune‐stimulatory functions in humans and livestock, but less information is available about the influence on meat quality of pigs when used as a feed additive. This study was designed to evaluate the effects of inactivated M. phlei on growth performance as well as meat quality of fattening pigs. A total of 240 cross‐bred pigs ([Landrace × Yorkshire] × Duroc) with initial body weight of 80.14 ± 0.29 kg were randomly allocated to five treatments, each of which consisted of eight replicates with 6six pigs per replicate. The basal diet supplemented with five levels of inactivated M. phlei preparations (0, 3.5 × 109 [0.1% w/w], 7 × 109 [0.2%], 1.4 × 1010 [0.4%] or 2.1 × 1010 [0.6%] colony‐forming units/kg) was respectively fed to the control group and four treatment groups for 30 days. Adding 0.4% of inactivated M. phlei to diet increased the average daily feed intake and average daily gain of pigs. Importantly, intramuscular fat percentage in the Longissimus dorsi (LD) was increased by feeding diet containing 0.2%, 0.4% and 0.6% of inactivated M. phlei, despite the pH value, drip loss, cooking loss and filter paper fluid uptake not being influenced. Analysis of the fatty acid components showed that some saturated fatty acids were decreased in LD after feeding inactivated M. phlei, but some monounsaturated fat acids (MUFAs) and polyunsaturated fatty acids were increased (PUFAs), which induced the total contents of MUFAs and PUFAs were improved. RT‐PCR assay revealed that feeding inactivated M. phlei up‐regulated genes implicated in fat metabolism in muscle, including ELOVL6, FASN, SCD1 and H‐FABP. This study revealed that feeding inactivated M. phlei not only increased growth performance of fattening pigs, but also improved the meat quality by increasing intramuscular fat content, thus inactivated M. phlei probably has high utilization value in modern pig production.  相似文献   

17.
The effects of dietary conjugated linoleic acid (CLA) on fatty acid composition, lipid oxidation, and pork quality were investigated. Pigs (n = 20) were fed a diet containing 0, 1, 2.5, or 5% CLA for 4 wk and slaughtered at 105 kg. The longissimus thoracis et lumborum muscle was collected at 24 h postmortem. Pork loin chops (3 cm thick) were packaged aerobically and stored at 4 degrees C for 7 d. Samples were analyzed for ultimate pH, intramuscular fat content, fatty acid composition, thiobarbituric acid-reactive substances, color (L*, a*, b*), and water-holding capacity. Dietary CLA reduced the concentration of linoleic acid and increased CLA concentration in intramuscular fat of pork loin (P < 0.05). The concentration of CLA in muscle was increased with dietary CLA level and did not change during storage. Thiobarbituric acid-reactive substance value of control was higher than that of the CLA-fed groups (P < 0.05). Intramuscular fat content was increased by dietary CLA, and less purge loss was observed with samples from CLA-fed pigs (P < 0.05). Dietary CLA improved the color stability of pork loin during cold storage. After 7 d, lightness (L*) and yellowness (b*) of the 5% CLA-fed group were significantly lower than those of control (P < 0.05). The results indicated that the water-holding capacity of pork loin was increased with increased intramuscular fat content apparently caused by dietary CLA. Also, the data indicated that color stability of pork was improved with inhibition of lipid oxidation and changing of fatty acid composition by dietary CLA.  相似文献   

18.
A trial was conducted to biochemically explain the decreased lipid deposition and increased protein accretion observed in pigs fed carnitine. Our hypothesis was that an increase in the ratio of acetyl CoA:CoA-SH produced by stimulation of fatty acid oxidation by supplemental L-carnitine may decrease branched-chain alpha-keto acid dehydrogenase activity and increase pyruvate carboxylase activity. Such changes could reduce oxidative loss of branched-chain amino acids and provide more carbons for amino acid biosynthesis. Yorkshire gilts (n = 36; 12 per treatment) were fed a control diet or diets containing either 50 or 125 ppm of added L-carnitine during growth from 56 to 120 kg. After slaughter, the semitendinosus muscle and liver were collected for isolation of mitochondria and hepatocytes. Increasing dietary L-carnitine did not influence growth performance (P > 0.10) but linearly decreased (P < 0.05) 10th rib backfat thickness and increased (linear, P < 0.05) percentages of lean and muscle. The rates of [1-(14)G]palmitate oxidation in isolated hepatocytes and isolated mitochondria, and incorporation of [35S]methionine into the acid insoluble fraction of isolated hepatocytes were increased (linear, P < 0.01) in pigs fed L-carnitine. Flux through branched-chain alpha-keto acid dehydrogenase linearly decreased (P < 0.01) in isolated liver and muscle mitochondria with increasing dietary carnitine. Flux through pyruvate carboxylase was increased (linear, P < 0.01) in isolated mitochondria from liver of pigs fed carnitine, and assays with particle-free extracts indicated that the amount of mitochondrial pyruvate carboxylase was tripled by feeding carnitine (linear, P < 0.01). The association of increased protein accretion and reduced backfat thickness with greater rates of palmitate oxidation, more rapid flux through pyruvate carboxylase, and reduced flux through branched-chain alpha-keto acid dehydrogenase suggests pigs fed carnitine are more able to use fat for energy, divert carbon toward synthesis of amino acids, and spare branched-chain amino acids for protein synthesis.  相似文献   

19.
莱芜猪胴体品质肉质特性及其随体重变化规律的研究   总被引：2，自引：0，他引：2  
研究测定了25头莱芜猪的胴体品质和肉质特性,分析了莱芜猪胴体、肌肉品质随体重(35、40、50、60、70、80、90kg)的变化规律,为确定不同生长阶段的适宜营养水平和上市屠宰体重提供依据.结果表明,莱芜猪自35～90kg瘦肉率在42.43%～55.29%之间,肌肉pH值稳定在6.19～6.52之间,肉色指标优良,大理石纹评分在2.50～4.38之间,肌内脂肪含量在4.51%～19.92%之间;当70kg体重屠宰时,肌肉失水率较低为13.47%,肉色、大理石纹评分较高分别为3.5、3.38,肌内脂肪含量较高为11.54%.胴体和肉质性状间相关程度有强有弱,相关系数有正有负.相同性状间有较强的正相关,相反性状间有较强的负相关.综合分析试验结果认为,莱芜猪以体重70kg作为上市屠宰体重比较合理.  相似文献   

20.
Forty-eight barrows and forty-eight gilts (PIC 337 sires x PIC C22 dams) were evaluated to determine the effects of feeding ractopamine hydrochloride (RAC) and different cereal grains on the carcass and fat quality in late finishing pigs. The study was carried out using four replicates with 24 animals in each replicate (four pigs per pen, six pens per replicate, two replicates per slaughter date, 12 pens per slaughter date). Treatments for the experiment included corn, wheat, and barley (early finisher period); and corn, corn + RAC, wheat, wheat + RAC, barley, and barley + RAC for the late finisher period. Ractopamine was fed at the level of 10 mg/kg (as-fed basis) of feed. Pigs were allotted to early finisher period treatments at approximately 45 kg BW. Pigs were then given late finisher period treatments at approximately 80 kg BW and fed for 28 d. The dietary digestible lysine level for all diets was maintained at 2.7 g/Mcal of ME. Pigs fed the wheat and corn diets during the late finisher period had a greater (P <0.05) G:F than those fed the barley diets. Pigs fed diets with RAC had lower (P <0.05) leaf fat weights, 10th-rib fat, last-rib fat, and belly firmness and had improved (P <0.05) dressing percents and loin muscle areas compared with those not receiving RAC. Pigs fed the wheat diets had a greater (P <0.05) dressing percent than those receiving the barley diets, but pigs fed the barley diets had a higher (P <0.05) Minolta L* for fat color than pigs fed wheat. Pigs fed diets containing RAC produced pork that was less tender (P <0.05) compared with pigs that did not receive RAC. Linoleic acid percent values were higher (P <0.05) for pigs fed diets with RAC than in those that did not. Feeding RAC improved G:F and lowered feed intake of pigs during the late finisher period (P <0.05). Feeding diets equal in lysine (2.7 g/Mcal of ME) but varying in ME, whether based on corn, wheat, or barley with or without RAC, had little to no effect on carcass, meat, or fat quality attributes.  相似文献   

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