the effect of the combination of microbial phytase and amino acid supplementation of diets for finishing pigs on p and n excretion and carcass quality

The objective of this study was to evaluate the effect of a combined low-protein, low-phosphorus diet supplemented with limiting amino acids and microbial phytase on performance, nutrient utilization and carcass characteristics of late-finishing barrows. 4?×?8 crossbreed barrows were continuously housed in metabolism cages from 70?–?110?kg BW and were fed diets, either conventional (A) or protein reduced (B) or protein and phosphorus reduced diets (C) based on barley, maize and soybean meal. Diet A (positive control) contained in air dry matter 13% and 10% CP as well as 0.49% and 0.42% P at growth phases I (70?–?100?kg BW) or II (100?–?110?kg BW), respectively. Diet B was low in CP (11.3%, 8.4%), diet C low in CP and low in P (CP: as B, P: 0.36%, 0.30%). To diet B the limiting amino acids lysine, methionine, threonine and trypthophan were added to meet the levels in diet A. To diet C the limiting amino acids and 800 FTU/kg Aspergillus-phytase were supplemented. At the end of the balance periods the barrows were slaughtered, the carcasses scored and loin chops, ham and Phalanx prima IV were analysed for nutrients and minerals. The CP or P reduction in diets B and C did not generally negatively affect growth, feed efficiency, absolute nitrogen retention or overall carcass performances of the pigs. With the low CP diets B and C, N excretion per unit BWG was decreased by about 23%. The addition of microbial phytase (diet C) increased apparent total tract digestibility of P by about 20%. In spite of 30% reduction of P intake (diet C), the absolute P retention related to 1?kg BW did not differ between treatments. Thus, phytase supplementation in diet C reduced P excretion per unit BWG by about 33%. Phytase raised apparent digestibility of Zn by about 20% but not Ca digestibility. Generally the carcass traits and meat characteristics were not affected by any of the diet strategies. Mineralization of the Phalanx prima IV was also similar in all treatment groups. However, phytase supplementation led to significantly increased zinc concentration in bones (25%). In contrast, Fe incorporation into the Phalanx prima IV was not affected. In general, the feeding regimen introduced in this experiment offers substantial benefits in maintaining a sustainable environmental-friendly pork production even at the stage of late-finishing barrows.     

Seal carrion is a predictable resource for coastal ecosystems

The timing, magnitude, and spatial distribution of resource inputs can have large effects on dependent organisms. Few studies have examined the predictability of such resources and no standard ecological measure of predictability exists. We examined the potential predictability of carrion resources provided by one of the UK's largest grey seal (Halichoerus grypus) colonies, on the Isle of May, Scotland. We used aerial (11 years) and ground surveys (3 years) to quantify the variability in time, space, quantity (kg), and quality (MJ) of seal carrion during the seal pupping season. We then compared the potential predictability of seal carrion to other periodic changes in food availability in nature. An average of 6893 kg of carrion ∙yr⁻¹ corresponding to 110.5 × 10³ MJ yr⁻¹ was released for potential scavengers as placentae and dead animals. A fifth of the total biomass from dead seals was consumed by the end of the pupping season, mostly by avian scavengers. The spatial distribution of carcasses was similar across years, and 28% of the area containing >10 carcasses ha⁻¹ was shared among all years. Relative standard errors (RSE) in space, time, quantity, and quality of carrion were all below 34%. This is similar to other allochthonous-dependent ecosystems, such as those affected by migratory salmon, and indicates high predictability of seal carrion as a resource. Our study illustrates how to quantify predictability in carrion, which is of general relevance to ecosystems that are dependent on this resource. We also highlight the importance of carrion to marine coastal ecosystems, where it sustains avian scavengers thus affecting ecosystem structure and function.     

Evaluation of Florina (Pelagonia) sheep breed for growth and carcass traits

Two experiments were conducted to evaluate the performance of growing Florina (Pelagonia) lambs fed a high concentrate diet, as well as the effect of slaughter weight on carcass characteristics. The assessment of the growth used 12 male and 12 female individually penned weaned lambs until they reached 60% of their mature body weight (BW), while assessment of the effect of slaughter weight at weaning (42 days of age), and at 30%, 45% and 60% of the mature BW, on carcass characteristics used 40 male and 40 female weaned lambs. In experiment 1, results showed that Florina lambs have good growth. Male lambs grew faster (P < 0.001) than female lambs, resulting in a lower (P < 0.001) feed conversion ratio (FCR) for males. Rate of gain, feed consumption and FCR increased (P < 0.001) as the experiment progressed. In experiment 2, results showed that degree of maturity affected (P < 0.001) fasted body weight and carcass weight, as well as all carcass characteristics and commercial cuts, except the steaks cut which did not differ. Florina lambs can be slaughtered in heavier carcass weights, heavier than the 15 kg as the present practice. The heavier carcasses can appeal to wider range of consumers due to the excellent muscle development and the reduced visible fat cover. Florina sheep raised for heavy carcass meat production may be more economically beneficial for the breeders and the increased meat produced locally can help reduce need for importing meat from abroad.     

Quantitative PCR assessment of microsatellite and SNP genotyping with variable quality DNA extracts

In this study we developed eight quantitative PCR (qPCR) assays to evaluate the starting copy number of nuclear and mitochondrial DNA fragments ranging from 75 to 350 base-pairs in DNA extracts from Chinook salmon tissues with varying quality. Samples were genotyped with 13 microsatellite and 29 SNP assays and average genotyping success for good, intermediate, and poor quality samples was 96%, 24%, and 24% for microsatellite loci, and 98%, 97%, and 79% for SNPs, respectively. As measured by qPCR, good quality samples had a consistently high number of starting copies across all fragment sizes with little change between the smallest and largest size. In contrast, the intermediate and poor quality samples displayed decreases in starting copy number as fragment size increased, and was most pronounced with poor samples. Logistic regression of genotyping success by starting copy number indicated that in order to achieve at least 90% genotyping success, approximately 1,000 starting copies of nuclear DNA are necessary for microsatellite loci, and as few as 14 starting copies for SNP assays (but we recommend at least 50 copies to reduce genotyping error). While these guidelines apply specifically to Chinook salmon and the genetic markers included in this study, the principles are transferable to other species and markers due to the underlying process associated with template quantity and PCR amplification.     

Effect of different protein–energy ratio in pulse by-products and residue based pelleted feeds on growth, rumen fermentation, carcass and sausage quality in Barbari kids

Thirty two Barbari kids (5-month old of 10.62 ± 0.09 kg BW, 16 males and 16 females) were equally divided into four groups to monitor growth, nutrient utilization, rumen fermentation, blood metabolites, carcass traits, meat and sausage quality on diet based on Cajanus cajan straw (60) and concentrate mixture (40) to have different protein–energy ratio in the diets (Diet 1—CP 12%, TDN 55%, Diet 2—CP 12%, TDN 60%, Diet 3—CP 14%, TDN 55% and Diet 4—CP 14%, TDN 60%). The experimental kids in each group were fed the respective diets at 4% of their body weight and limited quantity (300–400 g/kid/day) of oat fodder. The average DM intake/kg W^0.75 during growth period was significantly (P < 0.05) higher in Diet 1 (low protein–low energy) than Diet 4 (high protein–high energy). Kids under Diet 2 (low protein–high energy) and Diet 4 (high protein–high energy) gained 7.2% and 14.5% more weight respectively per day compared to those on Diet 1 (low protein–low energy), however, values of final body weight, average daily gain and feed conversion efficiency (%) were not significantly different (P > 0.05). The pH and total VFA concentration in the rumen liquor were similar (P > 0.05) among the four treatment groups. TCA precipitable-N was insignificantly (P > 0.05) higher in Diet 4 than other diets. Glucose, urea–nitrogen, total protein, albumin and globulin concentration in plasma were unaffected by treatments. TDN intake, DCP and TDN percentages were also similar (P > 0.05) among the four groups. Nitrogen balance (g/day/kid) values also showed no significant variation. Dietary effect was also not significant (P > 0.05) in the values of hot carcass weight, dressing percentage, carcass physical composition, variety meat yield and fat deposition but not breast fat thickness and kidney fat accumulation, which were significantly (P < 0.05) higher in Diet 2. Chemical composition values of Longissimus thoracis muscle were similar (P > 0.05) in percentage moisture, fat and ash, while CP was significantly (P < 0.05) higher in Diets 2 and 3 than Diets 1 and 4. There were no significant differences (P > 0.05) in the chemical composition of sausages prepared using meat from the kids of different treatments. Therefore, it may be concluded that pelleted feed of Diet 2 responded with better growth rate, quality of carcass traits and meat quality.     

Genetic variations in insulin-like growth factor binding protein acid labile subunit gene associated with growth traits in beef cattle (Bos taurus) in China

The insulin-like growth factor binding protein acid labile subunit (IGFALS) gene encodes a serum protein that binds to IGFs and regulates growth, development, and other physiological processes. We have found that sequencing of the IGFALS gene in Chinese Qinchuan beef cattle (n = 300) revealed four SNP loci in exon two of the gene (g1219: T>C, g1893: T>C, g2612: G>A, and g2696: A>G). The SNP g2696: A>G resulted in a change from asparagine to aspartic acid (p. N574D) in the leucine-rich repeat region in the carboxyl-terminal domain of IGFALS. Four SNPs were in low linkage disequilibrium, and 12 different haplotypes were identified in the population. Association analysis suggested that SNP g1219: T>C had a significant association with hip width (P < 0.05) and SNP g2696: A>G displayed a significant association with stature (P < 0.05). The results from our investigation indicated that polymorphisms in the IGFALS gene were associated with growth traits of bovine, and may serve as a genetic marker for selection of beef cattle for growth traits, including stature.     

Whole genome association study identifies regions of the bovine genome and biological pathways involved in carcass trait performance in Holstein-Friesian cattle

Background

Four traits related to carcass performance have been identified as economically important in beef production: carcass weight, carcass fat, carcass conformation of progeny and cull cow carcass weight. Although Holstein-Friesian cattle are primarily utilized for milk production, they are also an important source of meat for beef production and export. Because of this, there is great interest in understanding the underlying genomic structure influencing these traits. Several genome-wide association studies have identified regions of the bovine genome associated with growth or carcass traits, however, little is known about the mechanisms or underlying biological pathways involved. This study aims to detect regions of the bovine genome associated with carcass performance traits (employing a panel of 54,001 SNPs) using measures of genetic merit (as predicted transmitting abilities) for 5,705 Irish Holstein-Friesian animals. Candidate genes and biological pathways were then identified for each trait under investigation.

Results

Following adjustment for false discovery (q-value < 0.05), 479 quantitative trait loci (QTL) were associated with at least one of the four carcass traits using a single SNP regression approach. Using a Bayesian approach, 46 QTL were associated (posterior probability > 0.5) with at least one of the four traits. In total, 557 unique bovine genes, which mapped to 426 human orthologs, were within 500kbs of QTL found associated with a trait using the Bayesian approach. Using this information, 24 significantly over-represented pathways were identified across all traits. The most significantly over-represented biological pathway was the peroxisome proliferator-activated receptor (PPAR) signaling pathway.

Conclusions

A large number of genomic regions putatively associated with bovine carcass traits were detected using two different statistical approaches. Notably, several significant associations were detected in close proximity to genes with a known role in animal growth such as glucagon and leptin. Several biological pathways, including PPAR signaling, were shown to be involved in various aspects of bovine carcass performance. These core genes and biological processes may form the foundation for further investigation to identify causative mutations involved in each trait. Results reported here support previous findings suggesting conservation of key biological processes involved in growth and metabolism.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-837) contains supplementary material, which is available to authorized users.     

Effects of L-carnitine administration on growth performance,carcass traits,blood serum parameters and abdominal fatty acid composition of ducks

Effects of L-carnitine administration via drinking water on growth performance, carcass traits, blood serum parameters and abdominal fatty acid composition of ducks was examined. One hundred day-old Turkish native duck chicks were divided into two groups, each with five replicates and given the same diets with 0 and 200 mg/l carnitine chlorhydrate via drinking water. The study lasted 8 weeks, with the first 4 weeks as a starter and the last 4 weeks as grower period. At the end of the study five ducks were randomly selected from each subgroup for slaughter. Growth performance parameters of ducks were not affected significantly by L-carnitine administration. Live weight, daily weight gain, cumulative feed consumption and average feed conversion efficiency were found to be 1490 and 1621 g, 26.0 and 28.1 g, 5386 and 5662 g, 3.75 and 3.54 kg/kg in the control and in the carnitine groups respectively. L-carnitine administration did not effect carcass traits and serum cholesterol, total lipid, triglyceride and glucose levels. Total saturated fatty acid content of abdominal fat significantly decreased, mono- and polyunsaturated fatty acid content were not affected by L-carnitine administration. In conclusion, L-carnitine administration by drinking water did not affect growth performance, carcass traits and blood parameters in ducks.     

Effect of diets on growth,digestibility, carcass and meat quality characteristics of four rabbit breeds

The current study was conducted to evaluate three diets using four rabbit breeds. A total of 320 male weaned rabbits representing four breeds named V-line, Saudi-1, Saudi-2 and Saudi-3 were randomly distributed into three comparable dietary treatments. Three levels of indigenous feedstuffs (IFS) of 42.5%, 65% or 87.5% (alfalfa hay, barley and wheat bran) were substituted for the same levels of non-indigenous feedstuffs in the diet (corn grain, soybean, molasses, and limestone) to form three diets named D1, D2 and D3, respectively. These dietary treatments were used to evaluate post-weaning growth performance, feed intake, feed conversion, carcass and lean composition, and nutrients digestibility in four rabbit breeds.Partial replacement of IFS with non-indigenous feedstuffs attained significant increase in growth performance. The diet containing 87.5% IFS led to significant increase in daily weight gains by 8.4, 4.0, 8.1, 6.2 and 6.7 g at age intervals of 5–6, 7–8, 9–10, 10–11 and 11–12 weeks compared to the control diet, respectively. The diet containing 87.5% IFS showed a significant reduction in feed conversion ratio compared to control diet during the experimental periods. The diet containing 65% IFS showed significant increases in pre-slaughter weight (112 g) and hot carcass weight (89 g), while dressing percent, offal weight and percent, and non-carcass weights and percentages (head, fur, legs + tail, viscera) were not significantly different. The diet containing 87.5% IFS gave an increase of 1.1%, 6.4%, 8.8%, 17.9%, 7.4%, and 19.6% in digestibility coefficients of organic matter (OM), crude protein (CP), neutral detergent fibre (NFD), acid detergent fiber (ADF), hemi-cellulose (HC) and cellulose (C) compared to control diet, respectively.Feed intakes were moderate and ranged from 69 to 124 g for V-line, 77 to 128 g for Saudi-1, 79 to 130 g for Saudi-2, and 76 to 119 g for Saudi-3 along with moderate ratios of feed conversion ranging from 2.65 to 3.80, 2.45 to 3.90, 2.46 to 3.79 and 2.63 to 3.65, respectively. Pre-slaughter weight, hot carcass weight, and offal weight were in favour of Saudi-2 rabbits compared to the other groups. Both Saudi-1 and Saudi-2 rabbits were slightly higher than Saudi-3 in weights and percentages of head, fur, viscera and legs + tail. Lean and bone weights and percentages and meat to bone ratio in Saudi-2 carcasses were slightly higher than those recorded in the other groups, while moisture, DM, CP, EE and ash contents in the lean have shown little differences between groups. Rabbits of Saudi-1 were ranked the first in digestibility coefficients of OM, CP, NDF, ADF, HC, C and cell count compared to other groups.Rabbits of Saudi-2 fed diet containing 87.5% IFS recorded the heaviest body weights and gains since this class showed considerable deviations in body weights of 345, 341, 269, 307, 321, 345 and 347 g at 6, 7, 8, 9, 10, 11 and 12 weeks of age, respectively, in comparison with the lightest class. Both Saudi-2 and Saudi-3 rabbits fed the diet containing 87.5% IFS had favourable estimates of feed conversions ranging from 2.1 to 3.4, while rabbits of Saudi-1 fed the diet containing 87.5% IFS recorded the best digestibility coefficients.     

Growth performance and carcass quality of fattening lambs from fat-tailed and tailed sheep breeds

The growth performance and carcass traits of two fat-tailed breeds (Chaal and Zandi) and their crosses with rams of a tailed breed (Zel) were compared. After weaning, the growth and feed consumption of male and female lambs fattened for 114 days were recorded. A total of 45 male and female lambs were slaughtered and the left side of the carcasses were cut into six pieces, and the lean meat, bone, subcutaneous and intermuscular fat were determined. Average daily gain and feed conversion ratio in crossbred lambs improved, but the differences with pure lambs were not significant. The average weight of shoulder, brisket and loin were higher in crossbred than pure breed lambs (P < 0.01). The percentage of protein in the carcass of Zel × Zandi lambs was significantly higher than Zandi lambs. The smaller size and lower weight of fat-tail in crossbred lambs were compensated by higher percentage of subcutaneous, intermuscular and internal fat. The fat-tailed breeds provided good quality lean meat in terms of lower percentage of intermuscular fat.