Effects of genotype, level of supplementation, and organic chromium on growth performance, carcass, and meat traits grazing lambs

Influence of Dietary Supplementation of Inorganic and Organic Chromium on Body Conformation, Carcass Traits, and Nutrient Composition in Muscle and Internal Organs of Black Bengal Goats

The effect of dietary inorganic and organic chromium (Cr) on body morphometry, carcass traits, and nutrient composition, including different minerals and fatty acids in meat and internal organs of Black Bengal goats, was studied. Thirty weaned Black Bengal kids of 3-5 months (5.40 ± 0.34 kg body weight) were assigned randomly into five groups and fed additional Cr for 150 days. The experimental diets comprised a basal diet supplemented with Cr at the rate of 0 (control; without Cr supplementation), 1.0 and 1.5 mg/kg of inorganic Cr (Cr(III)-chloride), and 1.0 and 1.5 mg/kg of organic Cr (Cr-yeast). The body morphometry such as body length, heart girth, paunch girth, loin width, leg circumference, and the carcass traits, namely, slaughter body weight, dressing percentage, hind quarter and forequarter weight, and rib eye area of goats, were not significantly (P < 0.05) changed due to inorganic and organic Cr supplementation. However, organic Cr supplementation (1.0 and 1.5 mg/kg) resulted in a reduction of breast and back fat thickness (P < 0.05) compared with the control group. The weights of internal organs including liver, lungs, spleen, kidney, testes, and heart and their weights as a percentage of slaughter weight were similar (P > 0.05) among different experimental groups. Dry matter, ether extract, and total ash concentrations of muscle and internal organs of Cr-supplemented groups were not affected (P > 0.05) by Cr supplementation. However, crude protein contents in the liver, muscle, kidney, and lungs were greater (P < 0.05) in the organic Cr groups than in the control and inorganic Cr groups. In meat (longissimus dorsi muscle), total saturated fatty acid concentration was lower (P < 0.05; 59.4% versus 55.7%) and the unsaturated fatty acid concentration was greater (P < 0.05; 40.6% versus 44.3%) including palmitoleic acid, heptadecenoic acid, elaidic acid, and arachidonic acid in the organic or inorganic Cr-supplemented groups than in the basal diet group. In conclusion, dietary supplementation of organic Cr in Black Bengal goats has no influence on the carcass traits, but may improve the meat quality with greater protein content, lean, and healthier fatty acids for human consumption.

Review of Feeding Systems Affecting Production, Carcass Attributes, and Meat Quality of Ovine and Caprine Species

Growth rate, carcass attributes, and meat quality traits of small ruminants (i.e., sheep and goats) depend on various factors, among which the feeding system is one of the most important factors. However, how feeding systems affect these parameters differ between sheep and goats. Therefore, this review aimed to evaluate the differences in how different feeding systems affect the growth performance, carcass characteristics, and meat quality of sheep and goats. It also explored the effects of a new finishing strategy-time-limited grazing with supplements on these traits. Compared with stalled feeding, finishing lambs/kids on pasture-only feed reduced the average daily gain (ADG) and carcass yield, while supplemented-grazing lambs/kids had near-equivalent or higher ADG and carcass attributes. Pasture-grazing increased the meat flavor intensity and healthy fatty acid content (HFAC) of lamb/kid meat. Supplemental grazing lambs had comparable or superior meat sensory attributes and increased meat protein and HFAC compared to stall-fed ones. In contrast, supplemental grazing only improved the meat color of kids but had little effect on other meat qualities. Moreover, time-limited grazing with supplemental concentrates increased the carcass yield and meat quality in lamb meat. Overall, the effects of different feeding systems on growth performance and carcass traits were comparable between sheep and goats but differed in terms of the meat quality.

Rumen microbial-driven metabolite from grazing lambs potentially regulates body fatty acid metabolism by lipid-related genes in liver

BACKGROUND

Lipid metabolism differs significantly between grazing and stall-feeding lambs, affecting the quality of livestock products. As two critical organs of lipid metabolism, the differences between feeding patterns on rumen and liver metabolism remain unclear. In this study, 16S rRNA, metagenomics, transcriptomics, and untargeted metabolomics were utilized to investigate the key rumen microorganisms and metabolites, as well as liver genes and metabolites associated with fatty acid metabolism under indoor feeding (F) and grazing (G).

RESULTS

Compared with grazing, indoor feeding increased ruminal propionate content. Using metagenome sequencing in combination with 16S rRNA amplicon sequencing, the results showed that the abundance of propionate-producing Succiniclasticum and hydrogenating bacteria Tenericutes was enriched in the F group. For rumen metabolism, grazing caused up-regulation of EPA, DHA and oleic acid and down-regulation of decanoic acid, as well as, screening for 2-ketobutyric acid as a vital differential metabolite, which was enriched in the propionate metabolism pathway. In the liver, indoor feeding increased 3-hydroxypropanoate and citric acid content, causing changes in propionate metabolism and citrate cycle, while decreasing the ETA content. Then, the liver transcriptome revealed that 11 lipid-related genes were differentially expressed in the two feeding patterns. Correlation analysis showed that the expression of CYP4A6, FADS1, FADS2, ALDH6A1 and CYP2C23 was significantly associated with the propionate metabolism process, suggesting that propionate metabolism may be an important factor mediating the hepatic lipid metabolism. Besides, the unsaturated fatty acids in muscle, rumen and liver also had a close correlation.

CONCLUSIONS

Overall, our data demonstrated that rumen microbial-driven metabolite from grazing lambs potentially regulates multiple hepatic lipid-related genes, ultimately affecting body fatty acid metabolism.

Effects of Organic Chromium Yeast on Performance, Meat Quality, and Serum Parameters of Grow-Finish Pigs

Trivalent chromium (Cr) is an essential trace element for humans and animals. This study was conducted to investigate the effects of chromium(III) yeast (CrYst) on growth performance, carcass characteristics, meat traits, antioxidant status, immune traits, and serum biochemical parameters of grow-finish pigs. A total of 72 commercial hybrid barrows (Duroc × Landrace × Large White) of approximately 50 kg body weight were allocated into two dietary treatments randomly, which received a corn-soybean meal basal diet or a basal diet supplemented with 100 mg CrYst/kg. The trial duration was 11 weeks divided into three periods from body weights of 50-75 kg, 75-100 kg, and 100-110 kg, respectively. The results revealed that supplemental CrYst did not affect growth performance. Organic CrYst supplementation significantly decreased the backfat depth and increased the meat tenderness score and juiciness score values in pigs (P < 0.05), while other carcass traits and meat traits indexes were unaffected. CrYst addition significantly decreased serum malondialdehyde (MDA) content of pigs in the whole growth phase; significantly increased the serum levels of immunoglobulin G (IgG), total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px), and reduced glutathione (GSH) in growing pigs; and also increased the serum IgG, IgM, and GSH concentrations in pigs during the finishing phase (P < 0.05). Additionally, diets supplemented with CrYst significantly decreased the serum high-density lipoprotein cholesterol (HDL-C) content in growing pigs and significantly increased the serum LDL-C level at the fattening period (P < 0.05), whereas no significant differences were observed for the other serum biochemical indexes compared to the control pigs. In conclusion, CrYst supplementation could reduce lipid peroxidation and backfat thickness and improve the meat tenderness and juiciness, immune traits, and antioxidant status of pigs.

Performance and carcass characteristics of lambs fed diets containing different types of carbohydrates associated with polyunsaturated fatty acids

This study aimed to evaluate the productive performance and carcass characteristics of lambs fed diets with different types of carbohydrates associated with polyunsaturated fatty acids. Thirty castrated male lambs (20.5 ± 7.6 kg) were used, distributed in a randomized block design under three experimental diets: High proportion of non-fibrous carbohydrates (NFC) diet; High NFC diet + spineless cactus (high proportion of NFC and spineless cactus) and Low NFC diet (low proportion of NFC), in a 60 day experimental period. The variables of nutrient intake, performance, and carcass characteristics were evaluated. The animals fed the High NFC + spineless cactus diet presented a higher dry matter intake, organic matter, mineral matter, crude protein, and total carbohydrates intake (p <0.05). Carcass characteristics and weight of commercial cuts were improved in High NFC and High NFC + spineless cactus diets (p <0.05), on the other hand we observed a total fat weight reduction in animals fed with High NFC + spineless cactus. The results indicate that high levels of NFC positively influence animal performance, where the type of carbohydrate influences nutrient intake, also affecting carcass characteristics.

Carcass Traits, Meat Quality, and Volatile Compounds of Lamb Meat from Different Restricted Grazing Time and Indoor Supplementary Feeding Systems

This study was conducted to investigate the carcass traits, meat quality, and volatile compounds of growing lambs under different restricted grazing time and indoor supplementary feeding systems. Fifty 3-month-old male Tan lambs (with similar body weight) were divided into five groups randomly according to grazing time 12 h/d (G12), 8 h/d(G8), 4 h/d(G4), 2 h/d (G2), and 0 h (G0, indoor supplementary feeding). Animals were slaughtered at the end of the experiment, and the longissimus thoracis (LT) samples were collected for further analysis. The results indicated that indoor supplementary feeding improved the percentages of carcass fat and non-carcass fat of pre-slaughter weight (PSW) and decreased the cooking loss of lamb meat. Grazing for 8 h/d or 2 h/d enhanced PSW, carcass, and meat percentages of PSW. Lambs grazing for 2 h/d with supplement and indoor supplementary feeding lambs had a higher level of intramuscular fat and lightness (L*) value and lower cooking loss in the LT muscle, but higher yellowness (b*) and fat content were found in indoor supplementary feeding lambs. More categories of volatile compounds were identified in meat from grazing lambs than from indoor supplementary feeding lambs, but lower content of aldehydes and total volatile flavor compounds was detected in grazing lambs. Overall, the results demonstrated that the feeding system is a main factor that affects lamb meat quality, and proper grazing time can improve the quantity and quality of lamb meat and provide meat with different flavors to the consumers.

Effects of different feeding regimes on muscle metabolism and its association with meat quality of Tibetan sheep

This study aimed to explore the effects of different feeding regimes on muscle metabolism and its association with meat quality of Tibetan sheep through correlation analysis of meat quality and differential metabolites using untargeted and targeted metabolomics. The untargeted metabolome was detected by UHPLC-QTOF-MS, and the targeted metabolome was detected by UHPLC-QQQ-MS (amino acids) and GC-MS (fatty acids). Based on the researched results, the nutritional quality of meat, including the content of protein and fat and the edible quality of meat, including tenderness, water holding capacity (WHC), texture, and flavor of Tibetan sheep were superior in the stall-feeding group (GBZ) than in the traditional grazing group (CBZ). In the GBZ group, the key upregulated metabolites and metabolic pathways were dominated by essential amino acids (EAAs) and amino acid metabolism as well as the key downregulated metabolites and metabolic pathways were dominated by polyunsaturated fatty acids (PUFA) and lipid metabolism. Correlation analysis showed that there was a significant correlation between the results of untargeted metabolomics and some phenotypic data, including shear force, cooking loss, drip loss, chewiness, elasticity, flavor, and the content of protein and fat. Taken together, stall-feeding would be appropriate for the production of Tibetan mutton, offering better mouthfeel and higher nutrition by altering the muscle metabolism and increasing the beneficial compound deposition in the muscle.

Effects of concentrate level and chromium methionine supplementation on the performance, nutrient digestibility, rumen fermentation, blood metabolites, and meat quality of Tan lambs

Objective

This study was conducted to evaluate the effects of concentrate level and chromium methionine (Cr-Met) supplementation on the growth performance, carcass characteristics, meat quality, and fatty acid composition of Tan lambs.

Methods

Sixty male Tan lambs (21±1.23 kg body weight) fed a finishing diet (concentrate-to-forage ratio: 35:65 [LC group] or 55:45 [HC group]) with daily Cr-Met supplementation (0, 0.75, or 1.50 g) were used in a completely randomized design with a 2×3 factorial arrangement of treatments.

Results

Lambs from the HC group had higher average daily gain (ADG), dry matter (DM) digestibility, dressing percentages, leg proportions, intramuscular fat (IMF) contents, and saturated fatty acid levels, but lower feed conversion ratios, globulin (GLB) and total protein (TP) concentrations, shear force, and monounsaturated fatty acid (MUFA) levels (all p<0.05). Cr-Met supplementation increased the DM digestibility, GLB and TP concentrations, rack and loin percentages, and cooking loss, but decreased the IMF contents and leg proportions (all p<0.05). Cr-Met supplementation at 0.75 g/day increased the conjugated linoleic acid (CLA) content in both the HC and LC groups (p<0.01). Significant interactions between the concentrate level and Cr-Met dosage were observed for MUFA (p<0.01) and polyunsaturated fatty acid (PUFA) (p<0.01) levels. Meat from the lambs fed an unsupplemented LC diet presented the highest PUFA and MUFA levels (p<0.01). However, the MUFA and PUFA levels decreased significantly with increasing Cr-Met supplementation levels in the LC group (p<0.01), whereas the opposite trend was seen in the HC group.

Conclusion

The HC diet improved the growth performance of Tan lambs, increased their profitability by increasing leg and rack joint proportions, and improved meat quality by promoting an IMF content that was more visibly acceptable to consumers. Cr-Met supplementation at 0.75 g/day in a HC diet was the best choice and may be economically beneficial.

Untargeted and Targeted Metabolomics Profiling of Muscle Reveals Enhanced Meat Quality in Artificial Pasture Grazing Tan Lambs via Rescheduling the Rumen Bacterial Community

Tan is a local fat-tail sheep that is famous for its great eating quality but with little attention to its meat metabolome. The aim of this study was to investigate Tan-lamb meat metabolome as well as the key rumen bacteria related to the beneficial compound deposition in the muscle using untargeted and targeted metabolomics under different feeding regimes: indoor feeding (F), artificial pasture grazing with indoor feeding (GF), and pure artificial pasture grazing (G). The untargeted metabolome was detected by ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. Ruminal bacterial communities were detected by 16S rRNA sequencing. Using untargeted metabolomics, the main three altered metabolic pathways in the lamb, including amino acid, lipid, and nucleotide metabolisms, were found in the G group compared to the GF and F groups. Increased N-acetyl-l-aspartic acid, N-acetylaspartylglutamate, acetylcarnitine, and l-carnitine, but decreased carnosine and creatinine, were the main newly found G group-associated metabolites, which might contribute to the improved lamb meat functional quality. Compared to the F group, the G group feeding increased the contents of sweet amino acids (e.g., glycine, alanine, serine, and threonine) and umami amino acids (e.g., glutamic acid and aspartic acid) in the muscle, and G and GF groups increased the level of meat polyunsaturated fatty acid (PUFA), especially the concentration of n3 PUFA, and reduced n6/n3 in the muscle by targeted metabolomics. The abundance of ruminal Moryella was decreased, and Schwartzia and Anaeroplasma were increased in the G group, which were both strongly correlated with the n3 PUFA and other functional compounds in the muscle of lambs. In conclusion, artificial pasture grazing modified the meat amino acid and fatty acid composition as well as the related biological pathways through rescheduling the rumen bacterial community, which would be a better selection for production of healthier lamb meat products.

Carcass parameters and meat quality of Tibetan sheep and Small-tailed Han sheep consuming diets of low-protein content and different energy yields

Today, consumers are very health conscious and are more aware of the nutritional value of food, especially of meat, than they were in the past. The aim of this study was to evaluate the carcass parameters and meat quality of Tibetan sheep and Small-tailed Han sheep when consuming a diet of low-protein (~7%) and different energy yields (digestible energy, 8.21, 9.33, 10.45 and 11.57 MJ/kg) in the cold season. Twelve sheep of each breed were divided randomly into four treatments of different diets with three replicates per treatment per breed. Crude protein of the meat decreased linearly (p < .05), whereas energy increased linearly (p < .05) with an increase in energy level. Tibetan sheep tended to have a higher (p < .1) dressing percentage and rib eye area, while live body weight and hot carcass weight did not differ between breeds but increased linearly (p < .01) with an increase in energy level. Water holding capacity, as indicated by pressing loss and drip loss, did not differ between breeds and was not affected by dietary energy. The concentration of n-3 polyunsaturated fatty acids (PUFAs) was greater in Tibetan sheep meat but saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and n-6 PUFA did not differ between breeds. With an increase in energy content of the diet, SFA decreased (p < .05), whereas MUFA increased (p < .05). The n-6:n-3 PUFA ratio was lower (p < .001) in Tibetan sheep meat, while the atherogenic index did not differ between breeds, but tended to decrease (p < .1) with an increase in dietary energy content. The essential amino acid (EAA) content and ratio of EAA:NEAA (non-essential amino acid) were close to the world standards for healthy meat. In summary, (a) Tibetan sheep meat was preferable to Small-tailed Han sheep meat, although differences between breeds were small; and (b) some carcass parameters and meat quality were improved with an increase in dietary energy level when a low-protein diet was offered.

Dietary supplemental chromium and niacin influence the growth performance and fat deposition in lambs

Context Nowadays fat is an unpopular constituent of meat for consumers and therefore, a decrease in fat-tail size is often desirable for producers. Feed additives like chromium (Cr) and niacin (B3) have been reported to improve meat quality in beef and dairy cattle. However, their effect on meat quality and performance of fat-tail breeds of finishing lambs is unknown. Aim The aim of this study was to investigate the effect of supplemental chromium (Cr) and niacin (B3) on performance and fat deposition of carcass of finishing lambs. Methods Twenty male Zandi lambs (23.7 ± 0.73 kg) were allocated into one of four treatments: (1) control; (2) 300 µg/ kg DM Cr as chromium methionine; (3) 200 mg/kg DM B3 as rumen-protected niacin; and (4) 300 µg/ kg DM Cr as chromium methionine + 200 mg/kg DM B3 as rumen-protected niacin. Key results Chromium and B3 supplementation decreased blood glucose, insulin, triglycerides and low-density lipoprotein levels (P &lt; 0.05). Lambs fed diet supplemented with B3 consumed more feed with a higher growth (P &lt; 0.05) compared with other groups. There were no significant differences in feed efficiency, hot carcass weight, and dressing percentage among experimental groups. However, there was a decrease in the subcutaneous, abdominal, tail and total carcass fat in Cr supplemented lambs (P &lt; 0.01) compared with other experimental groups. The expression level of acetyl CoA carboxylase 1 (ACC1) and diglyceride acyltransferase 2 (DGAT2) genes was lower in Cr groups of lambs compared with other groups (P &lt; 0.05). Conclusions These results indicated that organic Cr supplementation improved meat quality by reducing fat accumulation, whereas B3 supplementation resulted in higher growth rate and feed intake. Implications Results showed that chromium supplementation reduces expression level of acetyl CoA carboxylase 1 and diglyceride acyltransferase 2 genes resulting in lower level of subcutaneous, abdominal, tail and total carcass fat of finishing lambs.

Effects of chromium picolinate on fat deposition, activity and genetic expression of lipid metabolism-related enzymes in 21 day old Ross broilers

Objective

This experiment was conducted to investigate the effects of chromium picolinate (CrP) on fat deposition, genetic expression and enzymatic activity of lipid metabolism-related enzymes.

Methods

Two hundred forty one-day-old Ross broilers were randomly divided into 5 groups with 4 replicates per group and 12 Ross broiler chicks per replicate. The normal control group was fed a basal diet, and the other groups fed the same basal diet supplemented with 0.1, 0.2, 0.4, and 0.8 mg/kg CrP respectively. The experiment lasted for 21 days.

Results

Added CrP in the basal diet decreased the abdominal fat, had no effects on subcutaneous fat thickness and inter-muscular fat width; 0.2 mg/kg CrP significantly decreased the fatty acid synthase (FAS) enzymatic (p<0.05); acetyl-CoA carboxylase (ACC) enzymatic activity decreased in all CrP groups (p<0.05); hormone-sensitive lipase (HSL) enzymatic activity also decreased, but the change was not significant (p>0.05); 0.4 mg/kg CrP group significantly decreased the lipoprotein lipase (LPL) enzymatic activity. FAS mRNA expression increased in all experimental groups, and the LPL mRNA expression significantly increased in all experimental groups (p<0.05), but not 0.2 mg/kg CrP group.

Conclusion

The results indicated that adding CrP in basal diet decreased the abdominal fat percentage, had no effects on subcutaneous fat thickness and inter-muscular fat width, decreased the enzymatic activity of FAS, ACC, LPL and HSL and increased the genetic expression levels of FAS and LPL.

The Effect of Extensive Feeding Systems on Growth Rate, Carcass Traits, and Meat Quality of Finishing Lambs

This review aims to summarize the relevant published information about the effects of extensive feeding systems on the carcass and meat quality characteristics of lambs. Lambs finished in a feedlot or with supplementation under extensive systems exhibit faster growth rates, achieve target weights quicker, and produce heavier carcass weights when compared to grazing lambs. However, the literature also shows that finishing lambs on high-quality pasture can produce satisfactory growth rates without compromising carcass and meat quality traits. Lately, the consumer demand for products perceived as "healthy" and that are produced where animal welfare is optimal under systems which do not impact negatively on the environment, has heightened the interest in lamb production under extensive systems. Lambs raised on pasture can meet many of these specifications. Also, lambs fed higher quality green pasture can produce meat with greater amounts of health-claimable omega-3 fatty acids such as eicosapentaenoic acid plus docosahexaenoic acid than feeding systems based on feedlot pellets, grain, or dry pasture/straw. It is apparent that in some previous published research, the number of animals allocated for each treatment, and the lack of replicates, makes it difficult to formulate a correct understanding of the effect of forages on lamb carcass and meat quality. Future research should concentrate on the effect of legume, improved pasture, and specialized forage finishing systems on growth rate, carcass traits, and nutritional value of meat using well-designed experiments with an adequate number of lambs and appropriate paddock replicates per treatment.

Effects of Supplemental Chromium Source and Concentration on Growth, Carcass Characteristics, and Serum Lipid Parameters of Broilers Reared Under Normal Conditions

An experiment was conducted to investigate the effects of dietary chromium (Cr) source and concentration on growth performance, carcass traits, and some serum lipid parameters of broilers under normal rearing conditions for 42 days. A total of 252 1-day-old Cobb 500 commercial female broilers were randomly allotted by body weight (BW) to one of six replicate cages (six broilers per cage) for each of seven treatments in a completely randomized design involved in a 2 × 3 factorial arrangement of treatments with three Cr sources (Cr propionate (CrPro), Cr picolinate (CrPic), Cr chloride (CrCl3)) and two concentrations of added Cr (0.4 and 2.0 mg of Cr/kg) plus a Cr-unsupplemented control diet. The results showed that dietary Cr supplementation tended to increase the breast muscle percentage compared with the Cr-unsupplemented control group (P = 0.0784), while Cr from CrPic tended to have higher breast muscle percentage compared with Cr from CrCl3 (P = 0.0881). Chromium from CrPic also tended to increase the breast intramuscular fat (IMF) compared with Cr from CrCl3 (P = 0.0648). In addition, supplementation of 0.4 mg/kg Cr tended to decrease low-density lipoprotein cholesterol (LDL-C) (P = 0.0614). Compared with the control group, broilers fed Cr-supplemented diets had higher triglyceride (TG) (P = 0.0129) regardless of Cr source and Cr concentration. Chromium from CrPro and CrPic had lower total cholesterol (TC) compared with Cr from CrCl3 (P = 0.0220). These results indicate that dietary supplementation of Cr has effects on carcass characteristics and serum lipid parameters of broilers under normal rearing conditions, while supplementation of organic Cr can improve carcass characteristics and reduce the cholesterol content in serum.

Effect Of Chromium Nicotinate On Oxidative Stability, Chemical Composition And Meat Quality Of Growing-Finishing Pigs

The effect of different organic sources of Cr on growth, feed efficiency and carcass value is known but there is a lack of information between chromium nicotinate (CrNic) and pork quality. Therefore, purpose of this research was to investigate the effects of CrNic on chemical composition, quality and oxidative stability of pork meat. In the study, pigs of Large White breed (40 pcs) were used. The pigs were divided into two groups, namely the control and the experimental of 20 pcs with equal number of barrows and gilts. The pigs were fed the same diet which consisted of three feed mixtures applied at the different growth phases, from 30 - 45 kg OS-03, 45 - 70 kg OS-04 and 70 - 100 kg OS-05. The pigs were allowed ad libitum access to feed and water. The diet of experimental group was supplemented with 0.75 mg.kg-1 CrNic in the form of chromium-inactivated yeast Saccharomyces cerevisiae. The fattening period in pigs lasted from 30 to 100 kg. The chromium supplementation led to a significantly higher content of chromium in longissimus thoracis muscle (LT) of experimental pigs. In addition, the results showed a statistically significant difference (p ≤0.05) in retention of chromium in the LT, monounsaturated and omega-3 polyunsaturated fatty acids content in experimental group compared with control. Moreover, there was highly significant (p £0.05) difference in essential fatty acids, as well as in oxidative stability in 7 days, among the groups. The highly significant differences were also observed among sexes, namely in total water, protein and intramuscular fat contents, colour CIE b* in both times, and oxidative stability. However, physical-technological parameters (pH, drip loss, shear force and meat colour) were not affected when pigs were fed the supplement. On the whole, the positive effect of chromium nicotinate in most of investigated parameters may be beneficial not only for pork industry but also for consumers.

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 ± 0.28 kg 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 800 μg/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 800 μg/kg decreased drip loss but increased shear force (P < 0.05). Pigs fed 100 or 400 μg/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 800 μg/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 400 μg/kg increased serum glutathione peroxidase activities (P < 0.05), and chromium at 800 μg/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 800 μg/kg chromium affected fatty acid compositions and reduced serum antioxidant capacity.

Evaluation of the effects of chromium supplementation on growth and nitrogen balance of camel calves under summer conditions

One of the most important problems in the production of camels in arid and semi-arid zones is the reduced feed intake and consequent low growth rate during summer. Under these stressful environmental conditions, chromium (Cr) supplementation to the diet of growing camel calves may be beneficial. Therefore, the objective of this study was to evaluate the effects of feeding a diet supplemented with different levels of Cr on growth performance of camel calves reared in a hot arid environment. A total of 15 male camel calves (4-5-month-old, 123 ± 7 kg body weight) were used in this study. The animals were divided into three equal groups (A, B, C), 5 animals each, and housed individually under shelter. Camel calves were fed ad libitum on either total mixed ration (TMR) without Cr supplementation (group A), TMR supplemented with 0.5 mg Cr/kg DM (group B), or TMR supplemented with 1.0 mg Cr/kg DM (group C). Supplementation of 0.5 mg Cr/kg DM to the diet of camel calves did not alter feed intake, however, increased not significantly (P = 0.086) average daily gain (ADG) and N retention. Plasma cortisol level was reduced by 10%, and feed utilization efficiency was improved by 12% in 0.5 mg Cr/kg DM-supplemented group compared to the control. Thus, 0.5 mg Cr/kg DM dietary supplementation to camel calves reared under hot summer condition increased weight gain by 17% and reduced feeding cost of producing a unit of weight by 11%.