Carcass Tissue Research Articles

Seasonality of goat warble fly infection by Przhevalskiana silenus (Diptera, Oestridae) in Italy

Among factors that negatively impact on livestock, parasite infections represent a serious challenge to the health, welfare, productivity and reproduction of goats. In Mediterranean countries for example larvae of Przhevalskiana silenus (Diptera, Oestridae) cause a myiasis known as goat warble fly infestation that may induce significant economic losses to goat productions. In this study carcasses of 580 goats (551 females and 29 males) from 48 farms, regularly slaughtered in southern Italy, were examined for P. silenus presence across two years (from January 2011 to December 2012). For each carcass, the skin and subcutaneous tissues were examined for larvae of P. silenus and, when retrieved, specimens were counted and classified according to their developmental stage. Overall, P. silenus larvae were detected in 42 (87.5%) out of 48 farms and in 285 (49.1%) out of 580 goats. The number of larvae ranged from 1 to 38 per infested goat, with a mean of 5.2 larvae (±4.8). A total of 1209 larvae were retrieved of which 385 were identified as first stage (L1), and 394 and 430 as second (L2) and third (L3) stage, respectively. The prevalence rate of infestation was significantly higher in younger goats compared to older (p=0.0298). Dynamic of larvae in inspected animals showed different patterns being higher in August, November and March for L1, L2 and L3, respectively.Results of this study showed that P. silenus infection is widespread among farms of the study area. Nevertheless, as it occurs in other Mediterranean countries, P. silenus infection is still an overlooked infestation in Italy and more awareness on this infection and adequate control strategies are advocated.

Antimicrobial Efficacy of a Lactic Acid and Citric Acid Blend against Shiga Toxin-Producing Escherichia coli, Salmonella, and Nonpathogenic Escherichia coli Biotype I on Inoculated Prerigor Beef Carcass Surface Tissue

Studies were conducted to (i) determine whether inoculants of nonpathogenic Escherichia coli biotype I effectively served as surrogates for E. coli O157:H7, non-O157 Shiga toxin-producing E. coli, and Salmonella when prerigor beef carcass tissue was treated with a commercially available blend of lactic acid and citric acid (LCA) at a range of industry conditions of concentration, temperature, and pressure; (ii) determine the antimicrobial efficacy of LCA; and (iii) investigate the use of surrogates to validate a hot water and LCA sequential treatment as a carcass spray intervention in a commercial beef harvest plant. In an initial laboratory study, beef brisket tissue samples were left uninoculated or were inoculated (∼6 log CFU/cm(2)) on the adipose side with E. coli O157:H7 (5-strain mixture), non-O157 Shiga toxin-producing E. coli (12-strain mixture), Salmonella (6-strain mixture), or nonpathogenic E. coli (5-strain mixture). Samples were left untreated (control) or were treated with LCA, in a spray cabinet, at one of eight combinations of solution concentration (1.9 and 2.5%), solution temperature (43 and 60°C), and application pressure (15 and 30 lb/in(2)). In a second study, the E. coli surrogates were inoculated (∼6 log CFU/cm(2)) on beef carcasses in a commercial facility to validate the use of a hot water treatment (92.2 to 92.8°C, 13 to 15 lb/in(2)) followed by an LCA treatment (1.9%, 50 to 51.7°C, 13 to 15 lb/in(2), 10 s). In the in vitro study, surrogate and pathogen bacteria did not differ in their response to the tested LCA treatments. Treatment with LCA reduced (P < 0.05) inoculated populations by 0.9 to 1.5 log CFU/cm(2), irrespective of inoculum type. The hot water and LCA sequential treatments evaluated in the commercial facility reduced (P < 0.05) the inoculated nonpathogenic E. coli surrogates on carcasses by 3.7 log CFU/cm(2). This study therefore provides the meat industry with data for this sequential multiple hurdle system for the operation parameters described.

Chlordecone disappearance in tissues of growing goats after a one month decontamination period--effect of body fatness on chlordecone retention.

Chlordecone (CLD) is an organochlorine pesticide whose extended use led to the contamination of at least 20% of agricultural soils from the French West Indies. Livestock reared on polluted areas are involuntary contaminated by CLD and their level of contamination may exceed the threshold values set by the European Union. Thus, characterizing the CLD behaviour in farm animals appear as a real issue in terms of food safety for local populations. The aim of this experiment was (i) to characterize the CLD disappearance in various tissues after exposure cessation and (ii) to evaluate the potential effect of body fatness on this process. Two groups of eight growing goats were submitted to either a basal diet or a high energy diet for 50 days before being intravenously contaminated with 1 mg CLD kg(-1) body weight. Two days after CLD contamination, half of the kids of each experimental group were slaughtered in order to determine pollutant levels in the serum, liver, adipose tissues, and empty carcass. The remaining animals were submitted to a 30-day decontamination period before slaughtering and measurements as described above. The implemented nutritional plan resulted in both groups of kids with significant differences in terms of body fatness. CLD was mainly concentrated in the liver of animals as described in the literature. It was found also in kids' empty carcass and adipose tissues; however its levels in the empty carcass (muscles and bones) were unexpected since they were higher than in fat. These results indicate that the lipophilic pollutant CLD is found mainly in liver but also in muscles and fat. Concerning the animals' depuration, a 30-d decontamination period was sufficient to observe a decrease of CLD levels by more than 75% in both experimental groups and neither CLD concentrations nor CLD amounts were significantly affected by kids' body fatness.

Características de carcaça e composição tecidual de ovinos Santa Inês alimentados com manipueira

The effects of replacing corn with manipueira + urea at 0; 25; 50; 75 and 100% in the diet of sheep on the carcass characteristics and tissue composition of the leg were studied. Forty sheep were distributed in a completely randomized design, with initial weight used as covariate, and slaughtered after 70 days of confinement. Slaughter body weight and carcass weights decreased linearly with the substitution, as well as hot carcass (42.77 to 39.12%) and commercial yields (41.22 to 37.55%) and longissimus muscle area (9.80 to 7.14 cm²). The weight of all meat cuts decreased linearly, but the yield of the same has not changed. There was a linear decrease to the rump width and carcass and leg compactness index. The weights of the tissue components of the leg, the percentage of muscles, the muscle: bone ratio and muscularity leg index (0.37 a 0.34 g cm-1) decreased with the replacement. The percentage of bones increased linearly (20.07 to 22.58%), but the fat percentage was not affected, as well as the muscle: bone ratio and subcutaneous fat: intermuscular fat ratio. It is not recommended to replace corn by manipueira + urea.

Age-related changes in the tissue composition of carcass parts and in the distribution of lean meat, fat with skin and bones in turkey carcasses

Summary Consumers show a preference for retail and market-ready cuts of turkey meat rather than entire carcasses. Carcass tissue composition changes as the bird grows, and tissue growth rates vary across the carcass. The objective of this study was to determine age-related changes in the tissue composition of carcass parts and in the distribution of lean meat, fat with skin and bones in turkey carcasses. The experimental materials comprised B.U.T. Big 6 turkeys: males between 2 and 20 weeks of age and females between 2 and 16 weeks of age.

Pathomorphological and microbiological studies in sheep with special emphasis on gastrointestinal tract disorders.

Aim:The present study was envisaged to elucidate the pathomorphological and microbiological aspects of gastrointestinal tract (GIT) disorders of sheep/lambs.Materials and Methods:Samples for research were collected from 12 sheep died with a history of GIT disorders which were brought for post-mortem examination to the Department of Veterinary Pathology, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, for pathomorphological and microbiological examination.Results:Gross pathological changes in various organs noticed were abomasitis, congestion and hemorrhages in intestine; necrotic foci on liver surface; enlarged, hard, and indurated mesenteric lymph nodes, hydropericardium, congestion, hemorrhages and consolidation of lungs and congestion and soft kidneys as the major change. On histopathological examination, there were abomasitis with leukocyte infiltration, enteritis with desquamation of mucosal epithelium and goblet cell hyperplasia, lymphadenitis with depletion of lymphocytes in the germinal center of lymphoid follicle, and splenitis with depletion of lymphocytes in the white pulp. In the liver congestion, degenerative changes in hepatocytes including cloudy swelling, fatty changes, congestion in sinusoids, and dilatation of sinusoids leading to atrophy of hepatocytes. Lungs evidenced edema, congestion, emphysema, serous inflammation, thickening of interlobular septa, fibrinous pleuritis, and peribronchiolar lymphoid follicle formation. Heart revealed sarcocystosis, fibrinous pericarditis, and hyalinization of the myocardium. In kidneys, congestion, focal interstitial nephritis, hyaline degeneration, and coagulative necrosis were seen. For microbiological aspects; cultural isolation was done from samples of liver, abomasum, mesenteric lymph nodes, spleen, heart blood, lungs, and kidneys from the carcasses of sheep/lambs. Escherichia coli was the only bacterium isolated during present studies. E. coli isolates from different tissues of carcasses of sheep/lambs were subjected to in-vitro drug sensitivity testing. Ciprofloxacin, cefixime, polymyxin B, amoxicillin + sulbactam, and amoxicillin + clavulanic acid were the most sensitive drugs followed by amikacin, ofloxacin, ampicillin, co-trimoxazole, and amoxicillin.Conclusions:From the present study, it is reasonable to conclude that the major etiopathological cause of GIT disorders in sheep was E. coli infection, which causes a pathomorphological effect on various cadaver organs viz. abomasum, intestine, liver, mesenteric lymph nodes, lungs, spleen, kidneys, and heart followed by parasitic infection of Haemonchus contortus.

Effects of Graded Levels of Chromium Methionine on Performance, Carcass Traits, Meat Quality, Fatty Acid Profiles of Fat, Tissue Chromium Concentrations, and Antioxidant Status in Growing-Finishing Pigs.

A 97-day feeding trial was conducted to investigate the effects of dietary chromium methionine (CrMet) on performance, carcass traits, meat quality, fatty acid profiles of fat, tissue chromium concentrations, and antioxidant status in growing-finishing pigs. A total of 180 crossbred pigs with a mean initial body weight (BW) 30.18 ± 0.28kg were allotted to 5 treatments with 6 replicates per treatment and 6 pigs per pen in a randomized complete block design based on BW and sex. Treatments were added with 0 (control), 100, 200, 400, and 800μg/kg chromium as CrMet. Blood samples were obtained from the anterior vena cava on days 97. Carcass characteristics, pork quality, and tissue chromium concentration data were collected from one pig per pen. The results indicated that supplemental CrMet did not significantly affect growth performance, carcass traits, or meat amino acid profiles. Chromium at 100, 400, and 800μg/kg decreased drip loss but increased shear force (P < 0.05). Pigs fed 100 or 400μg/kg had a higher 24-h pH than the control (P < 0.05). While meat color, muscle moisture, crude protein, or crude fat were not affected by CrMet. Supplemental 800μg/kg chromium reduced C18:0 levels in belly fat (P < 0.05), and chromium supplementation increased cis-9, trans 11-conjugated linoleic acid levels linearly (P < 0.05). Dietary CrMet supplementation increased serum, kidney, and muscle chromium contents (P < 0.05) but did not affect liver chromium contents. Besides, tissue chromium concentrations were increased linearly with increased chromium dosage (P < 0.05). Chromium at 400μg/kg increased serum glutathione peroxidase activities (P < 0.05), and chromium at 800μg/kg decreased serum total antioxidant capacity levels (P < 0.05). Nevertheless, liver and kidney antioxidant status were not significantly affected by CrMet. These results indicated that dietary supplementation CrMet did not significantly influence growth and carcass traits, but improved meat quality at the expense of tenderness. Therefore, the long-term exposure to 800μg/kg chromium affected fatty acid compositions and reduced serum antioxidant capacity.

PCR–RFLP analysis to identify four ray species of the genus Dasyatis (Elasmobranchii, Dasyatidae) fished along the southeastern and southern coast of Brazil

Fisheries statistics and stock assessment of many species of rays have been limited by the lack of information at the species level. Given the difficulty in identifying the four species within genus Dasyatis found in southeastern and southern Brazil, the aim of this work was to develop a methodology based on polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) of the mitochondrial cytochrome oxidase I (COI) gene to distinguish and register the capture frequencies of these species. Amplification of the COI region was performed using universal fish R1 and F2 primers, which generated amplicons of approximately 650bp that subsequently were sequenced. The FokI restriction enzyme was selected and generated specific DNA fragments for each species, with two fragments for Dasyatis hypostigma (390 and 260bp), three fragments for Dasyatis americana (300, 180 and 155bp), two fragments for Dasyatis guttata (370 and 300bp), and two fragments for Dasyatis centroura (410 and 200bp). The same enzyme then was used to identify 97 samples of ray carcass tissues collected from fishery landings, and revealed a species occurrence of 90.7% for D. hypostigma, 5.1% for D. americana, 2.1% for D. guttata, and 2.1% for D. centroura. Thus, the PCR–RFLP technique can be used to efficiently identify these four species and serves as an indicator of the current catch rates. Moreover, the method can help solve misidentification problems and can be used routinely to monitor landings and to establish and implement plans for fishery management.

Proposal for standard methods and procedure for guinea pig carcass evaluation, jointing and tissue separation

The South American guinea pig rodent has become a livestock animal acceptable for human consumption in different parts of the world. Its white meat has a great potential as a new protein source, and its social and economic importance for different human populations is considered key for development. Scarce data are found in the literature when the statistical livestock information is checked, and few researches have been done about morphological characteristics of guinea pigs carcasses. These works do not follow the same procedures, using different criteria, overall the jointing, making it difficult to compare different studies. The aim of the present study is to suggest a practical and normalized method to analyse the guinea pig carcass characteristics allowing their evaluation. It describes the main traits to be considered from the birth of the animal to the carcass analysis. This work concerns: (1) growth, feeding, pre-slaughter and slaughter processing, (2) method for the definition, hanging and presentation of the carcass, (3) carcass morphological characteristics, (4) jointing procedure based on four anatomically defined regions, (5) methods for evaluating meat pH and colour and (6) method for tissue separation. This proposal could be useful to compare data of these animals under different conditions.

Effects of dietary sulfur and distillers dried grains with solubles on carcass characteristics, loin quality, and tissue concentrations of sulfur, selenium, and copper in growing-finishing pigs.

Inclusion of up to 0.38% S in diets that contain 30% distillers dried grains with solubles (DDGS) has no negative effect on growth performance of growing-finishing pigs, but there is no information about the effects of dietary S on accumulation of S in tissues in pigs. Therefore, the objective of this experiment was to determine if the concentration of S in diets containing DDGS affects carcass characteristics, loin quality, or tissue mineral concentrations in growing-finishing pigs. A total of 120 barrows (34.2 ± 2.3 kg BW) were allotted to 3 dietary treatments with 10 replicate pens and 4 pigs per pen in a randomized complete block design. Pigs were fed grower diets for 42 d and finisher diets for 42 d. At the conclusion of the experiment, the pig in each pen with the BW closest to the pen average was slaughtered. The control diet was based on corn and soybean meal and the finisher diet contained 0.14% S, 0.19 mg/kg Se, and 15.3 mg/kg Cu. The DDGS diet was formulated with corn, soybean meal, and 30% DDGS and the finisher diet with DDGS contained 0.16% S, 0.32 mg/kg Se, and 14.0 mg/kg Cu. The DDGS plus S (DDGS-S) diet was similar to the DDGS diet, except that 1.10% CaSO4 (16.2% S) was included in this diet, and the finisher diet with DDGS-S contained 0.37% S, 0.35 mg/kg Se, and 13.8 mg/kg Cu. Results indicated that organ weights and loin quality, 24-h pH, drip loss, loin subjective color, marbling, and firmness did not differ among treatments, but loin a* was greater (P < 0.05) for pigs fed the control diet than for pigs fed the DDGS-S diet. Concentrations of S in hair, liver, heart, loin, and all other tissues did not differ among treatments, but urinary S concentration was greater (P < 0.05) for pigs fed the DDGS-S diet than for pigs fed the other diets. Pigs fed the DDGS diet or the DDGS-S diet had greater (P < 0.01) concentrations of Se in hair, liver, heart, and loin than pigs fed the control diet, but liver concentrations of Cu did not differ among treatments. In conclusion, inclusion of 30% DDGS in diets fed to growing-finishing pigs did not influence carcass characteristics or tissue S concentrations regardless of S concentration in the diet, and excess dietary S was excreted in the urine. However, because of the greater concentration of Se in DDGS than in corn and soybean meal and, therefore, greater concentrations in DDGS-containing diets, tissue concentrations of Se were increased in pigs fed diets that contained DDGS. In contrast, dietary DDGS did not influence liver concentrations of Cu.

Effect of corn silage and quantitative feed restriction on growth performance, body measurements, and carcass tissue composition in White Kołuda W31 geese

The objective of this study was to determine the effect of corn silage and quantitative feed restriction on BW, ADG, feed conversion, and carcass composition of White Kołuda W31 geese. Two diets were fed during the rearing period from 22 to 98 d of age: 1) a commercial diet ad libitum, and 2) restricted amounts of a commercial diet and corn silage ad libitum. Each treatment had 2 replicates of 16 birds each. From 99 to 119 d of age, all birds were fattened with whole oat grain alone. Incorporation of corn silage reduced weight gains and caused statistically significant differences in BW at the end of the rearing period (14 wk, 6,625.0 vs. 6,050.0 g;P < 0.05). Experimental geese showed compensatory growth during the oat fattening period and the BW of geese from both groups was similar at the end of the study (17 wk, 7,675.1 vs. 7,467.9 g;P > 0.05). Daily weight gains varied with week of growth, being lowest at 12 wk of age. Birds fed the commercial diet and corn silage had a significantly longer trunk (29.2 vs. 31.0 cm,P < 0.05) and shorter shanks (10.0 vs. 9.4 cm,P < 0.05) at 8 wk, and significantly smaller chest circumference (54.7 vs. 51.9 cm,P < 0.05) at the end of 14 wk. At the end of oat feeding (17 wk), geese receiving silage had significantly longer trunk and drumstick compared with geese fed commercial diets alone. The carcasses of 17-wk-old experimental geese contained more breast and leg muscles (%), and less skin with subcutaneous fat from breast and legs compared with control birds. Significant differences were only noted between the groups in dressing percentage (65.0 vs. 74.7%,P < 0.05) and proportion of skin with subcutaneous fat from breast (8.9 vs. 7.8%,P < 0.05). Dilution of the diet for young fattening geese with whole-crop corn silage had a positive effect on production economics and carcass composition.

Effect of egg white and its hydrolysate on stearoyl-CoA desaturase index and fat accumulation in rat tissues

We investigated the dietary effects of egg white (EW) and its hydrolysate (EWH) on fat metabolism in rats. Wistar rats were divided into casein, EW and EWH dietary groups, and fed their respective diet for 8 weeks. Dietary EW and EWH decreased food intake, body weight gain and fat accumulation in the carcass, liver, muscles and adipose tissues, but muscle weight was increased. In addition, dietary EW and EWH decreased stearoyl-CoA desaturase (SCD) indices and glucose-6-phosphate dehydrogenase activity of the liver and gastrocnemius muscle. Dietary EW also increased the fecal excretion of triacylglycerol, cholesterol and total bile acids, and decreased the serum levels of triacylglycerol and leptin. The suppressive effects of dietary EW on food intake and body fat accumulation were weakened by dietary EWH. These findings indicate that EW and EWH, especially EW, are effective in reducing body fat accumulation by regulating hepatic and muscular SCD indices.

Macronutrient optimization and seasonal diet mixing in a large omnivore, the grizzly bear: a geometric analysis.

Nutrient balance is a strong determinant of animal fitness and demography. It is therefore important to understand how the compositions of available foods relate to required balance of nutrients and habitat suitability for animals in the wild. These relationships are, however, complex, particularly for omnivores that often need to compose balanced diets by combining their intake from diverse nutritionally complementary foods. Here we apply geometric models to understand how the nutritional compositions of foods available to an omnivorous member of the order Carnivora, the grizzly bear (Ursus arctos L.), relate to optimal macronutrient intake, and assess the seasonal nutritional constraints on the study population in west-central Alberta, Canada. The models examined the proportion of macronutrients that bears could consume by mixing their diet from food available in each season, and assessed the extent to which bears could consume the ratio of protein to non-protein energy previously demonstrated using captive bears to optimize mass gain. We found that non-selective feeding on ungulate carcasses provided a non-optimal macronutrient balance with surplus protein relative to fat and carbohydrate, reflecting adaptation to an omnivorous lifestyle, and that optimization through feeding selectively on different tissues of ungulate carcasses is unlikely. Bears were, however, able to dilute protein intake to an optimal ratio by mixing their otherwise high-protein diet with carbohydrate-rich fruit. Some individual food items were close to optimally balanced in protein to non-protein energy (e.g. Hedysarum alpinum roots), which may help explain their dietary prevalence. Ants may be consumed particularly as a source of lipids. Overall, our analysis showed that most food available to bears in the study area were high in protein relative to lipid or carbohydrate, suggesting the lack of non-protein energy limits the fitness (e.g. body size and reproduction) and population density of grizzly bears in this ecosystem.

The Manx shearwater (Puffinus puffinus) as a candidate sentinel of Atlantic Ocean health.

IntroductionSeabirds have been historically used to monitor environmental contamination. The aim of the present study was to test the suitability of a species belonging to the Procellariiformes group, the Manx shearwater, Puffinus puffinus, as a sentinel of environmental health, by determining contaminant levels (trace metals and organochlorine compounds) from carcass tissues and by isolating Vibrio spp. and Aeromonas spp. from live specimens. To this end, 35 Puffinus puffinus carcasses wrecked on the north-central coast of the state of Rio de Janeiro, Brazil, and two carcasses recovered in Aracruz, on the coast of the state of Espírito Santo, Brazil, were sampled, and fragments of muscle and hepatic tissues were collected for contaminant analyses. Swabs from eleven birds found alive at the north-central coast of Rio de Janeiro were collected for isolation of the aforementioned bacteria.ResultsThe average concentration in dry weight (dw) of the trace metals were: mercury 7.19 mg kg-1(liver) and 1.23 mg kg-1 (muscle); selenium 34.66 mg kg-1 (liver) and 7.98 mg kg-1 (muscle); cadmium 22.33 mg kg-1 (liver) and 1.11 mg kg-1 (muscle); and lead, 0.1 mg kg--1 (liver) and 0.16 mg kg-1 (muscle). Organochlorine compounds were detected in all specimens, and hexachlorbiphenyls, heptachlorbiphenyls and DDTs presented the highest levels. Regarding microbiological contamination, bacteria from the Vibrio genus were isolated from 91% of the analyzed specimens. Vibrio harveyi was the predominant species. Bacteria from the Aeromonas genus were isolated from 18% of the specimens. Aeromonas sobria was the only identified species.ConclusionsThe results indicate that Puffinus puffinus seems to be a competent ocean health sentinel. Therefore, the monitoring of contaminant levels and the isolation of public health interest bacteria should proceed in order to consolidate this species importance as a sentinel.

Composição da carcaça de cordeiros terminados com dietas contendo grão de soja in natura ou desativado e dois níveis de concentrado

The objective was to evaluate the composition of carcass cuts and tissue of lambs shoulder and leg finished in feedlot receiving diets containing whole or disabled soybean grain with two concentrate levels (50% and 80% of DM). There were used 20 crossbreed entire male lambs, 120 days of age and initial body weight of 22.6 ± 2.06 kg. A completely randomized design was used, allocated in a factorial arrangement 2x2 (levels concentrate and processing of soybean grain). The slaughter criterion was body condition between 3 and 3.5. The weight of sirloin cut was superior with 80% of concentrate. In the shoulder tissue composition, the level of 50% concentrate increased the ratio of subcutaneous fat. In natura soybean provided higher values for weight and ratio of subcutaneous and total fat. For the leg tissue composition, the grain of disabled soybean showed higher muscle yield and muscle:bone ratio. Diets with 80% of concentrate, regardless of processing soybean grain, improved commercial yield and the diets containing disabled soybean more edible portion.

Consequences of nutrition during gestation, and the challenge to better understand and enhance livestock productivity and efficiency in pastoral ecosystems

The major economic costs to ruminant livestock producers of meat are associated with the breeding herd, which is an important target for improving productivity and efficiency at pasture. There is increasing interest in how to manage breeding females and their offspring to either minimise the consequences of adverse environmental effects or to enhance productivity and efficiency of offspring. This paper briefly reviews influences on fetal growth including the placenta, and reports results of our studies on factors including chronic, severe nutritional restriction during pregnancy and/or lactation within pasture-based systems on postnatal productivity of beef cattle. Cattle severely growth restricted early in life can have reduced weight for age to market weight, but with little or no alteration to normal allometric growth patterns of carcass tissues or beef quality, at least within pasture-based systems. The extent to which Bill McClymont’s vision of improving productivity and efficiency through improved understanding of the interactions between livestock, plants and soils can be realised is limited by our capacity to generate, in a timely manner, objective data on animal performance including intake and feed use efficiency within pastoral ecosystems. The capacity to improve productivity and efficiency, most notably for the breeding herd, within pastoral ecosystems will be enhanced by the development of wireless sensor networks and methods to manage and develop applications from ‘big data’. These applications of wireless sensor networks will include measurement of pasture intake, which is the input trait that underpins livestock production efficiency. Consistent with Bill McClymont’s vision, consumption of pasture by ruminants represents the point in the grazing ecosystem where livestock interface with plants and soils, and thus measurement of pasture intake should be a high priority for future research on productivity and efficiency.

Prediction of carcass composition and individual carcass cuts of Japanese Black steers

The objective of this study was to develop equations to predict carcass tissue weights and percentages and boneless carcass non-trimmed cut weights by using the cold carcass weight (CCW) and three other traits at the 6–7th rib section, which are routinely collected in carcass markets in Japan. Carcasses from 94 Japanese Black steers were used for the multiple regression analysis with a stepwise procedure and a novel Least Absolute Shrinkage and Selection Operator (LASSO). The accuracies of prediction (R2) and RMSEs for the carcass tissue and cut weights were similar between the two procedures. In contrast, LASSO appeared to be the better procedure for predicting carcass tissue percentages. The longissimus muscle area and subcutaneous fat thickness were the important predictors for the lean percentage in the stepwise procedure, and CCW was additionally selected when the LASSO procedure was used.

Tissue Distribution Kinetics of 2,2′,4,4′,5,5′-Hexachlorobiphenyl in Ringdoves After Oral Dosing

Ring doves were provided contaminated food spiked with [(13)C]-2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153) over a period of 63days. Animals were sacrificed after 0.33, 0.5, 1, 2, 4, 8, 18, 36 and 63days following access to contaminated food. At each time point, chemical concentrations in blood, liver, brain, gonad, adipose and remaining whole carcass was determined. Whole body concentrations of PCB 153 increased linearly with time over the experiment indicating that the birds did not reach steady state with their food after 63days. Tissue/plasma concentration ratios were plotted as a function of time to determine time to inter-tissue steady state for fast and slowly perfused tissues. Liver, brain and gonad achieved steady state concentrations with plasma in less than 3days, whereas fat and carcass tissues required 9.7 and 11.5days, respectively. The results indicate that inter-tissue distribution kinetics for PCBs in birds is relatively rapid and completed within a little over a week following exposure to a contaminated diet.

NIRS of body and tissues in growing rabbits fed diets with different fat sources and supplemented with Curcuma longa

A portable Near Infrared Reflectance Spectroscopy (NIRS) instrument was applied to 40 growing rabbits to determine body and tissue differences induced by experimental factors. The rabbits were examined at 2 live sites, in 7 warm carcass tissues and in longissimus dorsi muscle samples prepared in ethanol. For this purpose, the method was applied in a bi-factorial experiment concerning the dietary oil source (O) (maize vs. palm oil) and Curcuma longa (C) supplementation (0 and 3 g/kg, respectively). Significant chemical differences emerged for palmitic, oleic and linoleic acids in the longissimus dorsi muscle due to the O factor and for linolenic acid due to the C factor. The NIRS spectra and chemical analyses were elaborated by the Partial Least Squares (PLS) method, and the rsquares in cross-validation (R2cv) were retained as measure of the unoriented differentiation between the levels of the planned factor for each landmark and fatty acid (FA) profile. Multivariate PLS analysis of the FA muscular fat showed that the O factor induced strong differentiation (R2cv: 0.96), while less influence (0.33) was observed for the C factor. The model based on the NIRS radiation of the landmarks clearly shows the O factor effects, not only in the perirenal (0.90) and scapular (0.85) fats, but also in the belly (0.76), liver (0.73) and hind legs (0.72). Whereas the C effects were only expressed in the live animals (ears: 0.66 and abdominal wall: 0.58) and in post-mortem (liver: 0.60). It was concluded that a preliminary NIRS scan of the carcass and of live rabbits can point out the presence of intrinsic experimental effects concerning the lipid metabolism of polyunsaturated FA of the n-6 series (O factor) and n-3 series (C factor).

Effects of feeding system and slaughter age on the growth and carcass characteristics of tropical-breed steers1

This study aimed to compare the growth performances and carcass characteristics of tropical-breed steers reared in 2 contrasted feeding systems (indoor vs. pasture) and slaughtered at different ages (early vs. late). A total of 309 Creole steers (growing at an initial BW of 173 ± 3 kg and an initial age of 252 ± 4 d) were used over a continuous 12-yr study. Indoor steers were housed in a cattle shed, fed fresh-cut grass plus concentrate, and slaughtered at 14.5 or 17.1 ± 0.1 mo of age. Pasture steers were pasture grazed without supplemental feed, and slaughtered at 17.6 and 21.2 ± 0.1 mo of age. Indoor-fed steers had a greater ADG (786 vs. 517 ± 29 g•d(-1); P < 0.0001) and more carcass fat (164 vs. 145 ± 4.5 g•kg(-1); P = 0.001) than pasture-fed steers. Late-slaughtered steers had decreased ADG (630 vs. 673 ± 27 g•d(-1); P = 0.001) but greater dressing percentages (hot dressing percentage = 55.7 vs. 54.7 ± 0.34%; chilled dressing percentage = 54.5 vs. 53.4 ± 0.34%; P < 0.0001) than early-slaughtered steers. The interaction between feeding system and slaughter age was significant for carcass tissue composition. Whole-carcass muscle content was greater in late-slaughtered steers than early-slaughtered steers, especially in pasture-fed steers (720 vs. 698 ± 6.0 g•kg(-1); P < 0.0001), but less so in indoor-fed steers (707 vs. 700 ± 5.9 g•kg(-1); P = 0.046). Furthermore, increasing slaughter age had no effect on carcass fat in indoor-fed steers (162 vs. 166 ± 4.8 g•kg(-1); P = 0.342), but decreased carcass fat in pasture-fed steers (150 vs. 140 ± 5.0 g•kg(-1); P = 0.014). The results showed that slaughter age and feeding system are 2 major factors that independently affect most of the growth and carcass traits of tropical-breed steers but jointly influence tissue deposition. Our study found that in tropical-breed steers that are grazing, late slaughtering grazing steers increased carcass muscle content without extra fat, thus yielding a carcass quality better suited to consumer choices.