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Maisstärke, Maisquellstärke, Weizenstärke, Weizenquellstärke, Kartoffelstärke oder Maniokmehl werden in Anteilen von 41% bzw. 46,7% (Maniokmehl) einer Basalration zugemischt. Jede Versuchsration wurde an insgesamt 33 Karpfen (Cyprinus carpio L.) (drei Becken mit je 11 Karpfen) in einer Menge von 1,8‐ 2,0 % der Lebendmasse über eine einheitliche Versuchsdauer von 118 Tagen ab einer mittleren Lebendmasse von 146 g verfüttert. Die 4 Rationen auf Basis von Mais‐ bzw. Weizenstärke weisen insgesamt die gleiche, hohe Energieverdaulichkeit von etwa 90% auf. Die Zumischung von Kartoffelstärke bzw. von Maniokmehl verringert die Energieverdaulichkeit um 5 % bzw. 3% signifikant. Das Wachstum und der Futteraufwand werden durch die unterschiedlichen Stärkearten nicht beeinflußt. Zu Versuchsende weisen die Karpfen eine mittlere Masse von 520 g auf. Die Ganzkörper haben insgesamt mittlere Gehalte an Rohasche, Rohprotein und Gesamtfett bzw. Energie von 2,8, 15,7,9,4% bzw. 7,4 kJ pro g Frischmasse. Allerdings führt die Zumischung von Kartoffelstärke bzw. Maniokmehl zu einer deutlich geringeren Energieretention gegenüber Mais‐ und Weizenstärke, da die Trockensübstanz‐, Fett‐ und Energiegehalte dieser Karpfen signifikant niedriger sind.  相似文献   
3.
The concentrations of Fe, Zn, Cu and Mn were determined in meat, inner organs, blood and residual carcass in a total of 24 barrows and gilts of 60 kg and 100 kg of live weight, respectively. The finisher diet contained 192 ppm Fe, 113 ppm Zn, 18 ppm Cu and 65 ppm Mn with, as calculated, a great proportion originating from the mineral supplement. During growth, the contents of Fe, Cu and Mn were significantly reduced. No sex differences occurred. In the lean meat of the 100 kg pigs, common values accounting for 1.1 mg Fe, 2.8 mg Zn and 0.05 mg Cu per 100 g were analyzed. The manganese concentration of 0.01 mg per 100 g, however, was considerably lower as the corresponding figure from nutrient tables. In the finishing period, the animals retained per animal and day about 18 mg Fe, 15 mg Zn and 0.2 mg Cu. Mn retention was not significantly different from zero. The low utilization rates calculated from these data can be partly explained by the moderately excessive supply in this fattening period. In order to reduce the trace element load of the soils, a considerably lower tolerance of excessive trace element contents in finisher diets has to be developed.  相似文献   
4.
Meat colour is one of the most important meat quality traits affecting consumption desire. Genetic improvement for meat colour traits is not so easy because pigs can be phenotyped only after slaughter. Besides the parameters from the optical instrument, other indexes that reflect the material basis of meat colour should be measured accurately and used in the genomic analysis. Myoglobin (Mb) is the main chemical component determining meat colour. However, to what extent the Mb content contributes to meat colour, and whether it can be used as a trait for pig breeding to improve meat colour, and the correlations of Mb content with complex porcine traits are largely unknown. To address these questions, we measured the muscle Mb content in 624 pigs from the 7th generation of a specially designed eight breed-crossed pig heterogeneous population, evaluated its phenotypic and genetic correlations with longissimus thoracis colour score at 24 h after slaughter. More than that, we also systematically phenotyped more than 100 traits on these animals to evaluate the potential correlations between muscle Mb content and economically important traits. Our results showed that the average muscle Mb content in the 624 pigs was 1.00 mg/g, ranging from 0.51 to 2.17 mg/g. We found that higher Mb content usually correlated with favourable meat colour, higher marbling score, less moisture content, and less drip loss. Genetic correlation analysis between muscle Mb content and 101 traits measured in this study shows that Mb content is also significantly correlated with 31 traits, including marbling, shear force, firmness, and juiciness. To our knowledge, this is one of the largest studies about the correlations of muscle Mb content with as many as 100 various traits in a large-scale genetically diversified population. Our results showed that the Mb content could be a selection parameter for the genetic improvement of meat colour. The selection for higher Mb content will also benefit marbling, shear force, firmness, and overall liking but might not affect the growth, carcass, and fat deposition traits.  相似文献   
5.
The provision of suitable bedding for rearing broilers is an ongoing challenge for poultry producers. The aim of the present study was to evaluate the effect of using different types of crop residues as alternative bedding materials to wheat straw on growth performance, carcass traits, health, and welfare of broilers; moreover, the effects on the bedding and air quality were analyzed. We randomly assigned 180 1-day-old chickens (Cobb 500) across six bedding groups (three replicates of 10 birds each). Chickens in all groups were reared under similar housing conditions. Chickens of one group were reared on a wheat straw bedding (control), whereas those of the remaining five groups were reared on clover straw, cornstalk chips (CS), sugarcane top chips, chopped palm spines (CPS), and corn ear husks. Cornstalk chip and chopped palm spines were associated with the lowest (P < 0.05) ammonia concentrations compared with the remaining beddings. The mean values of bedding moisture percentage (P < 0.05), caking score, and ammonia concentrations (P < 0.05) were decreased with 6-week-old broilers reared on cornstalk chips. At 6 weeks, wheat straw, clover straw, sugarcane top chips and corn ear husks resulted in higher (P < 0.0001) BW and average daily gain compared with CS and CPS. Broilers reared on clover straw bedding showed the best FCR during 4–6 weeks of age (P < 0.01), and those kept on clover straw and sugarcane top chips exhibited the best (P < 0.01) feed conversion ratio (1.61 and 1.64, respectively) during 0–6 weeks of age. The carcass dressing yield, airborne dust concentration, bedding pH, and bacterial counts did not differ among the different bedding materials. The proportions of the drumsticks, gizzards, and abdominal fat of 6-week-old broilers were affected by bedding type (P < 0.05); but the differences among the bedding treatments were small. The mean incidence of footpad dermatitis and breast blisters was significantly less using clover straw. Broilers reared on chopped palm spine had the highest (P < 0.05) heterophil/lymphocyte ratio when compared with their counterparts. Conclusively, using clover straw or cornstalks as an alternative bedding material may be a beneficial strategy and should be highly recommended for rearing broilers.  相似文献   
6.
Two experiments were completed to examine effects of inclusion of a yeast culture (YC) to a diet based on barley grain and wheat straw on digestibility, growth and meat traits of Awassi lambs and Shami goat kids. Experiment 1 studied effects of YC on apparent digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and N balance in sheep, while experiment 2 studied effects on growth performance and carcass composition of lambs and kids. The same diet was used in both experiments and the YC was added to the diet of treated groups at the level of 12.6 kg YC/tonne of diet. Addition of YC had no effect on apparent digestibility of DM, CP and NDF, but it increased (P<0.05) digestibility of OM and ADF. No differences occurred in N intake, output or retention. Addition of YC did not affect growth rate, or DM intake, in both lambs and kids. YC supplementation to lambs reduced hot carcass weight, cold dressing proportion and total muscle/bone ratio, but increased empty digestive tract weight. There were no changes in back fat thickness, intermuscular fat of the leg muscle, and weights and proportions of carcass cuts. Measures of kids’ carcass characteristics and quality also did not differ. Only cuts of leg and shoulder differed (P<0.05) when calculated as a proportion of the whole carcass cut. Results show that YC supplementation increased digestibility with no effect on growth, feed intake or feed conversion ratio of fattening lambs and kids. However, YC supplementation reduced meat/bone ratio and tissue protein content, but increased fat content in carcasses of fattening Awassi lambs, but not in fattened Shami kids.  相似文献   
7.
The ca. 1.0 myr old fauna from Swartkrans Member 3 (South Africa) preserves abundant indication of carnivore activity in the form of tooth marks (including pits) on many bone surfaces. This direct paleontological evidence is used to test a recent suggestion that leopards, regardless of prey body size, may have been almost solely responsible for the accumulation of the majority of bones in multiple deposits (including Swartkrans Member 3) from various Sterkfontein Valley cave sites. Our results falsify that hypothesis and corroborate an earlier hypothesis that, while the carcasses of smaller animals may have been deposited in Swartkrans by leopards, other kinds of carnivores (and hominids) were mostly responsible for the deposition of large animal remains. These results demonstrate the importance of choosing appropriate classes of actualistic data for constructing taphonomic inferences of assemblage formation. In addition, they stress that an all-encompassing model of assemblage formation for the hominid-bearing deposits of the Sterkfontein Valley is inadequate and that each must be evaluated individually using not just analogical reasoning but also incorporating empirical data generated in the preserved fossil samples.  相似文献   
8.
The study aimed to investigate the effect of various doses of betaine supplemented dietary on Japanese quail performance, carcass characteristics, and blood chemistry. Therefore, 400 seven days old Japanese quails were classified randomly into four equal groups. Each group was subdivided into five replicates of 20 birds each. Four rations were formulated using four different betaine levels (0, 0.75, 1.5 and 2.25 g/kg, respectively) for five successive weeks. All groups received feed and clean water ad-libitum. The results of this trial indicated that the feed intake was lowered in groups fed with betaine (p ≤ 0.05) when compared with the control one. The highest weight gain (p ≤ 0.05) was noticed in groups fed diets BS4 (betaine supplementation at the rate of 2.25 g/kg). No difference among groups was observed in body length, shank length, shank diameter, and keel bone length or breast width. Also, the carcass weight and breast yield were highest (p ≤ 0.05) in the group reared on the BS4 diet. In addition, intestinal length and weight were significantly higher (p ≤ 0.05) in groups fed betaine with a concentration of 2.25 g/kg. Fat weight was lower in the group fed BS4 than in the untreated group. Significantly higher values of high-density lipoprotein (p ≤ 0.05) were observed in the group fed BS4. All groups fed a ration containing betaine showed lower levels of liver enzymes such as alanine amino transferase, alkaline phosphatase, and aspartate amino transferase (p ≤ 0.05) and lowered low-density lipoprotein level. The quails fed BS4 had the greatest growth hormones and insulin (p ≤ 0.05) and the lowest thyroxin level. We concluded that dietary betaine supplementation positively impacts Japanese quail growth performance, carcass traits, and blood chemistry.  相似文献   
9.
Mortality from collisions with increasing numbers of wind turbines is a potential hazard to raptor populations, but the actual effects on a population scale have rarely been studied based on field data. We estimated annual collision numbers for Red Kites Milvus milvus in the German federal state of Brandenburg (29,483 km2). A hierarchical model considering carcass persistence rate, searcher efficiency and the probability that a killed animal falls into a searched area was applied to results of carcass searches at 617 turbines. Collision risk varied significantly with season. The model estimated 308 (95% CrI 159–488) Red Kite fatalities at 3044 turbines operating during 2012, representing 3.1% of the estimated post-breeding population of 9972 individuals. Using the potential biological removal (PBR) method, mortality thresholds of 4.0% were obtained for migratory Red Kite populations. This level of mortality may be reached when turbine numbers increase within a few years. Since wind turbine collisions may affect Red Kites throughout the global range, a more detailed assessment of the actual impacts on populations is needed, especially because the PBR does not account for the predominance of adult birds among the collision victims.  相似文献   
10.
The traditional production of the Iberian breed pig involves a long production cycle. It might be shortened by using Iberian pigs crossed with Duroc and by reducing the growing phase, but the age-related changes on productive performance and carcass quality should be addressed. Thus, productive performance, live measurements and carcass and primal cut traits were evaluated on Iberian × Duroc 50:50 crossed pigs according to animal age at the beginning of the free-range finishing phase (Montanera): 10, 12 and 14 months old (IBxD10 (n = 15), IBxD12 (n = 17) and IBxD14 (n = 18) animal batches, respectively) and gender (immunologically castrated female -consisted of the Improvac® vaccination- and surgically castrated males). During the growing period, animals were fed with restrictions; 1.49, 1.29 and 1.20 ± 0.023 (mean ± SEM) kg/day of commercial feeds to start Montanera with similar BW; 103.9, 102.9 and 102.1 ± 0.22 kg, for IBxD10, IBxD12 and IBxD14, respectively. IBxD14 animals yielded the highest average daily gain (ADG) and BW after Montanera, as well as larger rump height and croup width. In contrast, these animals had the lowest carcass yield. Although animals from IBxD10 yielded hams of inferior size, this could be of interest to the sector, as there is a certain segment of the market that demands hams of smaller size and, generally, this is difficult to obtain with the traditional Montanera production system. The gender had no major effects on performance and carcass and primal cut traits, so both immunologically castrated female and surgically castrated males are suitable for finishing in Montanera.  相似文献   
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