The use of vitamin D3 and its metabolites to improve beef tenderness

Effects of supplemental 25-hydroxyvitamin D3 on growth performance, physiological responses, and gene expression of skeletal muscle growth of finishing beef cattle

The objective of this experiment was to evaluate the effects of 25-hydroxyvitamin D3 (25(OH)D3) supplementation on growth performance, carcass characteristics, meat quality, and the expression of genes related to anabolism of skeletal muscle in finishing beef cattle. One hundred and twenty Nellore bulls (initial body weight [BW] = 376 ± 20 kg) were blocked by initial BW, allocated to 24 pens (5 bulls/pen) and pens were assigned to one of three treatments during a 96 d feeding experiment: control: high-concentrate basal diet (11% roughage; NEg = 1.16 Mcal/kg dry matter) with no supplemental 25(OH)D3 (0 mg of 25(OH)D3; n = 8 pens); basal diet containing supplemental 25(OH)D3 to provide 1 mg/animal/d (1 mg of 25(OH)D3; n = 8 pens), 3) basal diet containing supplemental 25(OH)D3 to provide 3 mg/animal/d (3 mg of 25(OH)D3; n = 8 pens). The dietary supplementation of 25(OH)D3 did not affect final BW, dry matter intake, average daily gain, and feed efficiency (P ≥ 0.32). Dressing percentage increased quadratically (P = 0.03) and Longissimus muscle area tended to increase quadratically (P = 0.09) with increasing levels of 25(OH)D3 supplementation. A treatment × day interaction was observed for plasma concentration of 25(OH)D3 (P < 0.001). No difference in plasma 25(OH)D3 concentration between treatments was observed at the beginning of the experiment (P > 0.05), but on days 37 and 95, plasma 25(OH)D3 was greater (P ≤ 0.05) for bulls fed 3 mg, followed by 1 mg, and 0 mg of 25(OH)D3. No effects of dietary supplementation of 25(OH)D3 were observed on meat quality attributes (P ≥ 0.24), except for meat pH that linearly increased (P < 0.01). The percentage of fat in the carcasses decreased linearly (P = 0.03) with increasing levels of 25(OH)D3 supplementation, followed by a numerical increase (P = 0.11) in the percentage of muscle. The gene expression of insulin-like growth factor-2 (IGF2), mammalian target of rapamycin, and myostatin tended (P ≤ 0.10), and IGF1 increased linearly (P = 0.04) with increasing levels of 25(OH)D3. In summary, the inclusion of 25-hydroxyvitamin D3 in feedlot diets may go beyond regulating calcium metabolism and meat quality only. Dietary supplementation of 1 mg of 25(OH)D3 for finishing beef cattle increased carcass dressing percentage and Longissimus muscle area by the upregulation of genes associated with skeletal muscle growth insulin-like growth factor-1 and 2, mammalian target of rapamycin, and myostatin.

Edible Offal as a Valuable Source of Nutrients in the Diet-A Review

The global increase in demand for meat leads to substantial quantities of by-products, including edible offal from both wild and domesticated animals raised for diversified consumption products within an agricultural framework. Information on the nutritional value of offal is scattered and limited. This review aims to synthesize scientific publications on the potential of offal as a source of nutrients and bioactive substances in human diets. The literature review included publications available in ISI Web of Science and Google Scholar published between 2014 and 2024. Findings indicate that edible offal is characterized by a nutrient concentration often surpassing that found in skeletal muscle. This review discusses the yield of edible offal and explores factors influencing human consumption. Selected factors affecting the nutritional value of offal of various animals and the importance of individual nutrients in ensuring the proper functioning of the human body were analyzed. The optimal use of offal in processing and catering can significantly benefit aspects of human life, including diet quality, food security, and conservation of natural resources.

Effects of Zilpaterol Hydrochloride with a Combination of Vitamin D3 on Feedlot Lambs: Growth Performance, Dietary Energetics, Carcass Traits, and Meat Quality

This study evaluated the impact of supplementing ZH in combination with D3 on the growth performance, energy efficiency, carcass traits, and meat quality of feedlot lambs. Thirty-two Dorper × Katahdin cross lambs (37.3 ± 5.72 kg) were utilized in a 29 d experiment in a completely randomized block design with a 2 × 2 factorial structure consisting of two levels of ZH for 26 d (0 and 0.20 mg/kg PV-1) and two levels of D3 for 7 d (0 and 1.5 × 106 IU/d-1). ZH improved (p ≤ 0.05) the average daily gain (ADG) and feed efficiency by 9.9% and 17.8%, respectively, as well as hot carcass weight (HCW) and dressing carcass by 4.3% and 2.6%, respectively. (p ≤ 0.03). However, ZH increased (p < 0.01) muscle pH and Warner-Bratzler shear force (WBSF) (2.5 and 23.0%, respectively). D3 supplementation negatively affected (p ≤ 0.02) dry matter intake (DMI) (last 7 d) and ADG by 15.7% and 18.1%. On the other hand, D3 improved the pH of the longissimus thoracis muscle by 1.7% (p = 0.03) without affecting WBSF. When D3 was supplemented in combination with ZH, it was observed that meat quality was improved by reducing muscle pH compared to lambs treated only with ZH. However, D3 did not improve the meat tenderness negatively affected by ZH supplementation.

Meat tenderness: advances in biology, biochemistry, molecular mechanisms and new technologies

Meat tenderness is an important quality trait critical to consumer acceptance, and determines satisfaction, repeat purchase and willingness-to-pay premium prices. Recent advances in tenderness research from a variety of perspectives are presented. Our understanding of molecular factors influencing tenderization are discussed in relation to glycolysis, calcium release, protease activation, apoptosis and heat shock proteins, the use of proteomic analysis for monitoring changes, proteomic biomarkers and oxidative/nitrosative stress. Each of these structural, metabolic and molecular determinants of meat tenderness are then discussed in greater detail in relation to animal variation, postmortem influences, and changes during cooking, with a focus on recent advances. Innovations in postmortem technologies and enzymes for meat tenderization are discussed including their potential commercial application. Continued success of the meat industry relies on ongoing advances in our understanding, and in industry innovation. The recent advances in fundamental and applied research on meat tenderness in relation to the various sectors of the supply chain will enable such innovation.

Oral 25-Hydroxycholecalciferol Acts as an Agonist in the Duodenum of Mice and as Modeled in Cultured Human HT-29 and Caco2 Cells

BACKGROUND

25-Hydroxycholecalciferol [25(OH)D] is the predominant circulating metabolite of vitamin D and serves as the precursor for 1α,25-dihydroxycholecalciferol [1,25(OH)2D], the hormonally active form. The presence of 1α-hydroxylase (1α-OHase) in the intestine suggests that 1,25(OH)2D can be produced from 25(OH)D, but the effects of oral 25(OH)D on the intestine have not been determined.

OBJECTIVES

We investigated the acute intestinal response to orally consumed 25(OH)D in mice by assessing mRNA induction of cytochrome p450 family 24 subfamily A member 1 (Cyp24), a vitamin D-dependent gene. The mechanism of action then was determined through in vitro analyses with Caco2 and HT-29 cells.

METHODS

Adult male C57BL6 mice were given a single oral dose of 40, 80, 200, or 400 ng 25(OH)D (n = 4 per dose) or vehicle (n = 3), and then killed 4 h later to evaluate the duodenal expression of Cyp24 mRNA by qPCR and RNA in situ hybridization. The 25(OH)D-mediated response was also evaluated with Caco2 and HT-29 cells by inhibition assay and dose-response analysis. A cytochrome p450 family 27 subfamily B member 1 (CYP27B1) knockdown of HT-29 was created to compare the dose-response parameters with wild-type HT-29 cells.

RESULTS

Oral 25(OH)D induced expression of Cyp24 mRNA in the duodenum of mice with 80 ng 25(OH)D by 3.3 ± 0.8 ΔΔCt compared with controls (P < 0.05). In vitro, both Caco2 and HT-29 cells responded to 25(OH)D treatment with 200-fold and 175-fold greater effective concentration at 50% maximal response than 1,25(OH)2D, yet inhibition of 1α-OHase and knockdown of CYP27B1 had no effect on the responses.

CONCLUSIONS

In mice, orally consumed 25(OH)D elicits a vitamin D-mediated response in the duodenum. In vitro assessments suggest that the response from 25(OH)D does not require activation by 1α-OHase and that 25(OH)D within the intestinal lumen acts as a vitamin D receptor agonist.

Vitamin D-biofortified beef: A comparison of cholecalciferol with synthetic versus UVB-mushroom-derived ergosterol as feed source

This study investigates dietary fortification of heifer feeds with cholecalciferol and ergocalciferol sources and effects on beef total vitamin D activity, vitamer, respective 25-hydroxymetabolite contents, and meat quality. Thirty heifers were allocated to one of three dietary treatments [(1) basal diet + 4000 IU of vitamin D₃ (Vit D₃); (2) basal diet + 4000 IU of vitamin D₂ (Vit D₂); and (3) basal diet + 4000 IU of vitamin D₂-enriched mushrooms (Mushroom D₂)] for a 30 day pre-slaughter period. Supplementation of heifer diets with Vit D₃ yielded higher (p < 0.001) Longissimus thoracis (LT) total vitamin D activity (by 38-56%; p < 0.05) and serum 25-OH-D concentration (by 20-36%; p < 0.05), compared to that from Vit D₂ and Mushroom D₂ supplemented animals. Irrespective of vitamin D source, carcass characteristics, sensory and meat quality parameter were unaffected (p > 0.05) by the dietary treatments. In conclusion, vitamin D₃ biofortification of cattle diets is the most efficacious way to enhance total beef vitamin D activity.

Beef Tenderness Improvement by Dietary Vitamin D3 Supplementation in the Last Stage of Fattening of Cattle

Tenderness is the most important characteristic of meat, determining consumer approval. There are numerous methods of its improvement, although of diverse effectiveness. addition of vitamin D₃ to the feed for a short period before slaughter (7–10 days) is one of the natural ways to enhance the tenderness. Vitamin D₃ is responsible for Ca²⁺ mobilisation in serum and increase in activity of proteolytic enzymes belonging to calpains, which results in significant improvement of beef tenderness and reduction of ageing time. The use of vitamin D₃ is an application tool determining tenderness improvement of beef with substantial reduction in processing costs. Moreover, shorter post mortem ageing process will exceed the retail display time, which will consequently reduce losses due to unsold meat being returned from shops to the manufacturers. Based on the results of studies conducted over the last 15 years, this paper presents the possibility and the effects of the use of vitamin D₃ to improve beef tenderness.

Including food 25-hydroxyvitamin D in intake estimates may reduce the discrepancy between dietary and serum measures of vitamin D status

The discrepancy between the commonly used vitamin D status measures-intake and serum 25-hydroxyvitamin D [25(OH)D] concentrations--has been perplexing. Sun exposure increases serum 25(OH)D concentrations and is often used as an explanation for the higher population-based serum concentrations in the face of apparently low vitamin D intake. However, sun exposure may not be the total explanation. 25(OH)D, a metabolite of vitamin D, is known to be present in animal-based foods. It has been measured and reported only sporadically and is not currently factored into U.S. estimates of vitamin D intake. Previously unavailable preliminary USDA data specifying the 25(OH)D content of a subset of foods allowed exploration of the potential change in the reported overall vitamin D content of foods when the presence of 25(OH)D was included. The issue of 25(OH)D potency was addressed, and available commodity intake estimates were used to outline trends in projected vitamin D intake when 25(OH)D in foods was taken into account. Given the data available, there were notable increases in the total vitamin D content of a number of animal-based foods when potency-adjusted 25(OH)D was included, and in turn there was a potentially meaningful increase (1.7-2.9 μg or 15-30% of average requirement) in vitamin D intake estimates. The apparent increase could reduce discrepancies between intake estimates and serum 25(OH)D concentrations. The relevance to dietary interventions is discussed, and the need for continued exploration regarding 25(OH)D measurement is highlighted.

Calcitriol enhances fat synthesis factors and calpain activity in co-cultured cells

We have conducted an in vitro experiment to determine whether calcitriol can act as a fat synthesizer and/or meat tenderizer when skeletal muscle cells, adipose tissue, and macrophages are co-cultured. When co-cultured, pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) expression increased, whereas decreased anti-inflammatory cytokine (IL-10 and IL-15) expression decreased in both C2C12 and 3T3-L1 cells. Calcitriol increased reactive oxygen species (ROS) production in the media. While adiponectin gene expression decreased, leptin, resistin, CCAAT-enhancer-binding protein-beta (C/EBP-β), and peroxisome proliferator-activated receptor gamma (PPAR-γ) gene expression was significantly (P < 0.047) increased with calcitriol in 3T3-L1 cells co-cultured with two different cell types. Inducible nitric oxide synthase (iNOS) protein levels were also stimulated in the C2C12 and 3T3-L1 cells, but arginase l was attenuated by calcitriol. Cacitriol highly amplified (P = 0.008) µ-calpain gene expression in co-cultured C2C12 cells. The results showed an overall increase in pro-inflammatory cytokines and a decrease in anti-inflammatory cytokines of C2C12 and 3T3-L1 cells with calcitriol in co-culture systems. µ-Calpain protein was also augmented in differentiated C2C12 cells with calcitriol. These findings suggest that calcitriol can be used as not only fat synthesizer, but meat tenderizer, in meat-producing animals.

Stability of vitamin D in foodstuffs during cooking

We investigated the retention of vitamin D3 and 25-hydroxyvitamin D3 in eggs, vitamin D3 in margarine, and vitamin D3 and vitamin D2 in bread. Our set-up illustrated the cooking methods usually performed in households i.e. boiling, frying in pan and oven, and baking. All experiments were performed three times independently of one another. The retention of vitamin D compounds in eggs and margarine during heat treatment in an oven for 40 min at normal cooking temperature showed retention at 39-45%, while frying resulted in retention at 82-84%. Boiled eggs were found to have a similar level of retention (86-88%). For bread baked, as recommended in the recipe, the retention of vitamin D3 in rye bread at 69% was lower than the retention in wheat bread at 85%. A similar observation was made for vitamin D2, although the retention was slightly higher, 73% and 89%. No difference between retention of vitamin D3 and 25-hydroxyvitamin D3 in eggs was shown. Cooking may cause detrimental loss of vitamin D, but it depends on the actual foodstuffs and the heating process. Further research is needed to optimise cooking procedures to enhance retention of vitamin D. Vitamin D retention should be taken into account in future calculations of dietary intake of vitamin D.

Desempenho, características qualitativas da carcaça e da carne de novilhas Brangus suplementadas em pastagem recebendo diferentes aditivos nutricionais

Objetivou-se avaliar a eficiência de dietas contendo diferentes aditivos sobre o desempenho, características qualitativas da carcaça e da carne de 150 novilhas Brangus suplementadas a pasto diariamente com 0,32% do peso vivo. Os tratamentos foram: suplemento base (sem aditivos); farinha de algas calcárias (Lithothamnium calcareum) adicionada ao suplemento base; vitamina E e selênio orgânico adicionados ao suplemento base; gordura protegida adicionada ao suplemento base; uma aplicação por via subcutânea de vitamina D 7 dias antes do abate + suplemento base; e uma associação de vitamina E, selênio orgânico e gordura protegida adicionados ao suplemento base + uma aplicação por via subcutânea de vitamina D 7 dias antes do abate. Os animais foram suplementados por 109,80 ± 11,71 dias, quando foram abatidos ao alcançarem 337,95 ± 20,56kg de PV. O delineamento experimental foi inteiramente casualizado, com seis tratamentos e 25 repetições. O desempenho, as características de carcaça e da carne não foram afetados pelos aditivos utilizados. A média da área de olho de lombo de 52,00 cm² e a média da espessura de gordura subcutânea de 3,58mm dos animais que receberam a associação de aditivos não diferiram dos valores dos animais do tratamento controle. A adição de vitamina D3 não teve efeito sobre a força de cisalhamento da carne. O uso de aditivos conforme os protocolos adotados não foi eficiente para melhorar o desempenho, as características de carcaça e as características físicas da carne de novilhas suplementadas a pasto.

Natural vitamin D content in animal products

Humans derive most vitamin D from the action of sunlight in their skin. However, in view of the current Western lifestyle with most daily activities taking place indoors, sun exposure is often not sufficient for adequate vitamin D production. For this reason, dietary intake is also of great importance. Animal foodstuffs (e.g., fish, meat, offal, egg, dairy) are the main sources for naturally occurring cholecalciferol (vitamin D-3). This paper therefore aims to provide an up-to-date overview of vitamin D-3 content in various animal foods. The focus lies on the natural vitamin D-3 content because there are many countries in which foods are not regularly fortified with vitamin D. The published data show that the highest values of vitamin D are found in fish and especially in fish liver, but offal also provides considerable amounts of vitamin D. The content in muscle meat is generally much lower. Vitamin D concentrations in egg yolks range between the values for meat and offal. If milk and dairy products are not fortified, they are normally low in vitamin D, with the exception of butter because of its high fat content. However, as recommendations for vitamin D intake have recently been increased considerably, it is difficult to cover the requirements solely by foodstuffs.

The influence of latitude on the concentration of vitamin D3 and 25-hydroxy-vitamin D3 in Australian red meat

There is little information on the vitamin D content of Australian red meat or on the possible influence of latitude on this content. To determine the content of vitamin D3 and 25-hydroxy-vitamin D3 (25OHD3), lamb and beef were analysed from 34° S with LC-IT-MS. To investigate the possible influence of latitude on vitamin D in meat, the lean meat and fat from five cuts of beef were analysed from 17° S and 41° S. Lamb contained 0.10μg vitamin D3/100g and 0.20μg 25OHD3/100g lean meat, while beef contained 0.12μg vitamin D3 and 0.27μg 25OHD3/100g (lean meat). Latitude had no effect on the vitamin D3 (P=0.21) or 25OHD3 (P=0.29) content of lean beef, but fat from cattle in the 17° S latitude group contained significantly higher (P<0.01) concentrations of vitamin D3 than fat from the 41° S group of cattle.

Vitamin D₃ regulation of body fat, cytokines, and calpain gene expression

BACKGROUND

We conducted an in vivo experiment to determine whether vitamin D₃ acts as a fat synthesizer and/or meat tenderizer in mice. At 6 weeks of age, 20 male C57BL/6 wild-type mice were randomly divided into two groups (10 mice per group) and fed a modified AIN93G diet with (vitamin D₃ diet) or without (basal diet) 10 IU 25-OH-cholecalciferol kg⁻³ for 3 weeks.

RESULTS

When vitamin D₃ was fed to mice for 3 weeks, body fat was significantly increased compared to mice fed a basal diet. There was, however, no difference in body weight between the two groups. Vitamin D₃ increased the gene expressions of pro-inflammatory cytokines and peroxisome proliferator-activated receptor gamma, but decreased interleukin-15 in adipose tissue through nuclear vitamin D receptor and uncoupling protein-2 signals. The muscle inducible nitrate oxide synthase content of mice fed vitamin D₃ was higher than those fed a basal diet, while muscle arginase l showed a reverse phenomenon. longissimuss dorsi muscle of vitamin D₃-fed mice showed more severe fat deposition than those fed a basal diet. Vitamin D₃ amplified muscle u- and m-calpain protein content and suppressed muscle calpastatin protein content.

CONCLUSION

These findings suggest that vitamin D3 can be used as a fat synthesizer and meat tenderizer in meat-producing animals.

Effect of short-term UVB exposure on vitamin D concentration of eggs and vitamin D status of laying hens

Vitamin D deficiency in humans is widespread, and only a few food items are important natural sources of vitamin D. This study investigated the effect of UVB exposure of laying hens on the vitamin D content in egg yolk. In a two-factorial design, hens fed a vitamin D-deficient (-D) or -adequate (+D) diet were nonexposed or exposed to UVB light over a period of 4 weeks. UVB exposure of the -D group caused nearly normal egg production rate and egg shell quality; exposure of the +D group did not further improve these parameters. UVB exposure tended to improve the concentration of plasma 25-hydroxycholecalciferol (25(OH)D(3)), but had no effect on 1,25-dihydroxycholecalciferol in plasma or on cholecalciferol and 25(OH)D(3) in egg yolk. The present study shows that a short-term exposure of laying hens to UVB light is not an appropriate way to improve the vitamin D content of egg yolk.

Association and expression quantitative trait loci (eQTL) analysis of porcine AMBP, GC and PPP1R3B genes with meat quality traits

The aim of this research was to screen polymorphism and to perform association study of porcine AMBP (alpha-1-microglobulin/bikunin precursor), GC (group-specific component protein) and PPP1R3B (protein phosphatase 1, regulatory (inhibitor) subunit 3B) genes with meat quality traits as well as to unravel the transcriptional regulation of these genes by expression QTL (eQTL) study. For this purpose, Duroc × Pietrain F2 resource population (DuPi; n = 313) and a commercial breed Pietrain (Pi; n = 110) were used for association and only DuPi for expression and eQTL study. A SNP was identified in the genes AMBP (g.22229C>T), GC (g.398C>T) and PPP1R3B (c.479A>G), respectively. In DuPi SNP of AMBP was associated (P < 0.05) with meat colour, pH(1L), pH(24L), pH(24H) and conductivity(24L); SNP of GC showed tendency to association (P < 0.10) with pH24H, conductivity(1L) and thawing loss, and SNP of PPP1R3B was associated (P < 0.05) with meat colour, pH(1L), pH(24L), pH(24H) and shear force. In Pi SNPs of AMBP and GC was associated with pH(24H) and PPP1R3B SNP was associated with pH(24L). The mRNA levels in Longissimus dorsi muscle tissue of these three genes were evaluated by using qRT-PCR to identify association between gene expression and meat quality traits as well as to analyse eQTL. The mRNA expression of PPP1R3B associated with pH(24L) (P < 0.05). Expression of these three genes was higher in animals with low pH of muscle. Linkage analysis using QTL Express revealed ten trans-regulated eQTL on seven porcine autosomes. Suggestive eQTL [P < 0.05, CW (chromosome-wide)] were found for PPP1R3B on SSC3 and 13. These results revealed that genetic variation and gene expression of these genes are associated with the meat quality traits. These three genes could influence meat quality and could be potential positional, physiological and functional candidate gene for meat quality traits in pigs. However, the analysis of eQTL also suggested that we need to consider additional genes encoding for transcription factors (TF), via fine-mapping underlying the eQTL peaks, in order to understand interaction among these genes.

Use of 25-hydroxyvitamin D3 and vitamin E to improve tenderness of beef from the longissimus dorsi of heifers

The objective of this trial was to determine whether a single bolus of 25-hydroxyvitamin D(3) (25-OH D(3)), vitamin E, or a combination of the 2 would improve the tenderness of steaks from the LM of beef heifers. Forty-eight Angus crossbred heifers were allotted randomly to 8 pens. Six heifers were in each pen, and there were 2 pens per treatment. The 4 treatments included control (no 25-OH D(3) or vitamin E); 25-OH D(3) (500 mg of 25-OH D(3) administered as a one-time oral bolus 7 d before slaughter); vitamin E (1,000 IU of vitamin E administered daily as a top-dress for 104 d before slaughter); or combination (500 mg of 25-OH D(3) administered as a one-time oral bolus 7 d before slaughter and 1,000 IU of vitamin E administered daily as a top-dress for 104 d before slaughter). Blood samples were obtained on the day that heifers were allotted to treatments, on the day 25-OH D(3) was administered, and on the day before slaughter. Plasma calcium concentration was increased when 25-OH D(3) was administered with or without vitamin E (P < 0.007). In LM, calcium concentration tended to increase (P = 0.10) when 25-OH D(3) was administered alone but not when 25-OH D(3) was administered with vitamin E. Concentrations of 25-OH D(3) and 1,25-dihydroxyvitamin D(3) in plasma were increased when 25-OH D(3) was administered with or without vitamin E (P < 0.001). Steaks from heifers treated with 25-OH D(3) or vitamin E, but not both, tended to have lower Warner-Bratzler shear force than steaks in the control group at 14 d postmortem (P = 0.08). Postmortem protein degradation as measured by Western blot of the 30-kDa degradation product of troponin-T was increased with all treatments after 3 d postmortem (P </= 0.07), but not at 7 or 14 d postmortem. Unexpectedly, the use of 500 mg of 25-OH D(3) fed as an oral bolus 7 d before slaughter or 1,000 IU of vitamin E administered daily for 104 d before slaughter alone, but not in combination, effectively decreased Warner-Bratzler shear force.

Effects of 25-hydroxyvitamin D3 and manipulated dietary cation-anion difference on the tenderness of beef from cull native Korean cows

In this study, we characterized the effects of 25-hydroxyvitamin D3 (25-OH D3) and manipulated dietary cation-anion difference (DCAD) on the performance, urine pH, serum constituents, carcass traits, tissue residual vitamin D and its metabolites, beef tenderness, and mRNA and protein concentrations of Ca-dependent proteinases in LM using 24 cull native Korean cows. The cows were divided into 3 groups of 8: control, 25-OH D3 supplemented (25-OH D3), and manipulated DCAD plus 25-OH D3 supplemented (DCAD+25-OH D3). Cows receiving 25-OH D3 or DCAD+25-OH D3 were dosed with 125 mg of 25-OH D3 6 d before slaughter. The manipulated DCAD (-10 mEq/100 g of DM) diet was fed from 20 to 6 d (14 d) before slaughter. The DCAD+25-OH D3 treatment decreased urine pH and increased serum Ca concentrations. Although the vitamin D concentrations in LM, liver, and kidney were not affected by 25-OH D3 or DCAD+25-OH D3, muscle tissue 25-OH D3 concentrations were increased by both regimens. Serum 25-OH D3 concentrations were increased by 25-OH D3 supplementation, and the increase was even greater for DCAD+25-OH D3. The same pattern was observed for serum 1,25- (OH)2 D3. However, the LM concentration of 1,25-(OH)2 D3 was less for DCAD+25-OH D3 than for control. Although Ca concentrations of LM increased numerically in response to 25-OH D3 supplementation, no statistical differences in Warner-Bratzler shear force or sensory traits of LM were detected. The LM of cows receiving 25-OH D3 with or without manipulated DCAD had greater concentrations of mu-calpain and m-calpain mRNA, whereas the reverse was observed for calpastatin mRNA. Expression of mu-calpain protein was increased relative to control by DCAD+25-OH D3. The amount of 25-OH D3 and manipulated DCAD administered to cull native Korean cows was insufficient to improve tenderness of beef by increasing muscle Ca concentration. However, DCAD+25-OH D3 induced greater expressions of mu-calpain protein as well as mRNA.

The efficacy of a vitamin D(3) metabolite for improving the myofibrillar tenderness of meat from Bos indicus cattle

The influence of a once only administration of a metabolite of vitamin D(3) (HY·D(®)-25-hydroxy vitamin D(3)) on myofibrillar meat tenderness in Australian Brahman cattle was studied. Ninety-six Brahman steers of three phenotypes (Indo-Brazil, US and US/European) and with two previous hormonal growth promotant (HGP) histories (implanted or not implanted with Compudose(®)) were fed a standard feedlot ration for 70d. Treatment groups of 24 steers were offered daily 10g/head HY·D(®) (125mg 25-hydroxyvitamin D(3)) for 6, 4, or 2d before slaughter. One other group of 24 steers was given the basal diet without HY·D(®). Feed lot performance, blood and muscle samples and carcass quality data were collected at slaughter. Calcium, magnesium, potassium, sodium, iron and Vitamin D(3) metabolites were measured in plasma and longissimus dorsi muscle. Warner-Bratzler (WB) shear force (peak force, initial yield) and other objective meat quality measurements were made on the longissimus dorsi muscle of each steer after ageing for 1, 7 and 14d post-mortem at 0-2°C. There were no significant effects of HY·D(®) supplements on average daily gain (ADG, 1.28-1.45kg/d) over the experimental period. HY·D(®) supplements given 6d prior to slaughter resulted in significantly higher (P<0.05) initial yield values compared to supplements given 2d prior to slaughter. Supplementation had no significant effect on meat colour, ultimate pH, sarcomere length, cooking loss, instron compression or peak force. There was a significant treatment (HY·D(®)) by phenotype/HGP interaction for peak force (P=0.028), in which Indo-Brazil steers without previous HGP treatment responded positively (increased tenderness) to HY·D(®) supplements at 2d when compared with Indo-Brazil steers previously given HGP. There were no significant effects of treatment on other phenotypes. HY·D(®) supplements did not affect muscle or plasma concentrations of calcium, potassium or sodium, but did significantly decrease plasma magnesium and iron concentrations when given 2d before slaughter. There were no detectable amounts of 25-hydroxyvitamin D(3) in the blood or muscle of any cattle at slaughter.

Supplemental vitamin D3 concentration and biological type of steers. II. Tenderness, quality, and residues of beef

Vitamin D3 was orally supplemented to determine the supplemental dose that improved beef tenderness in different cattle breed types. Feedlot steers (n = 142) were arranged in a 4 x 3 factorial arrangement consisting of four levels of supplemental vitamin D3 (0, 0.5, 1, and 5 million IU/steer daily) administered for eight consecutive days antemortem using three biological types (Bos indicus, Bos Taurus-Continental, and Bos Taurus-English). Warner-Bratzler shear force (WBSF) was measured at 3, 7, 10, 14, and 21 d postmortem, and trained sensory analysis was conducted at 7 d postmortem on LM, semimembranosus, gluteus medius, and supraspinatus steaks. Concentrations of vitamin D3 and the metabolites 25-hydroxyvitamin D3, and 1,25-dihydroxyvitamin D3 were determined in the LM, liver, kidney, and plasma. Biological type of cattle did not interact (P > 0.10) with vitamin D3 supplementation for sensory or tenderness traits, suggesting that feeding vitamin D3 for 8 d before slaughter affected the different biological types of cattle similarly. Supplementing steers with 0.5, 1, or 5 million IU/(steer(d) decreased (P < 0.05) LM WBSF at 7, 10, 14, and 21 d postmortem compared with controls, and vitamin D3 treatments of 0.5, 1, and 5 million IU decreased (P < 0.05) semimembranosus WBSF at 3, 7, and 14 d postmortem. In general, vitamin D3-induced improvements in WBSF were most consistent and intense in LM steaks. Sensory panel tenderness was improved (P < 0.05) by all vitamin D3 treatments in LM steaks. Sensory traits ofjuiciness, flavor, connective tissue, and off-flavor were not (P > 0.05) affected by vitamin D3 treatments. All vitamin D3 treatments decreased micro-calpain activity and increased muscle Ca concentrations (P < 0.05). Vitamin D3 concentrations were increased (P < 0.05) by supplementation in all tissues tested (liver, kidney, LM, and plasma); however, cooking steaks to 71 degrees C decreased (P < 0.05) treatment residue effects. The vitamin D metabolite 1,25-dihydroxyvitamin D3 was increased (P < 0.05) only in plasma samples as a result of the vitamin D3 treatments. These results indicate that supplementation with vitamin D3 at 0.5 million IU/steer daily for eight consecutive days before slaughter improved tenderness in steaks from different subprimal cuts by affecting muscle Ca concentrations, micro-calpain activities, and muscle proteolysis, with only a small effect on tissue residues of vitamin D3.