A dose-response study relating the concentration of carotenoid pigments in blood and reflectance spectrum characteristics of fat to carotenoid intake level in sheep1

Visible spectroscopy on lamb fat and muscle to authenticate the duration of pasture finishing

Pasture-based livestock systems are considered environmentally-sustainable and welfare-friendly farming systems that can meet consumer demand for good-quality produce. However, trust in products labelled as 'grass-fed' depends on the ability to reliably authenticate pasture origin. The two objectives of this study were (i) to test the ability of visible spectroscopy combined with discriminant analysis on lamb perirenal fat (PF), dorsal fat (DF) and longissimus thoracis et lumborum muscle to discriminate different durations of pasture-finishing; and (ii) to determine the timing of appearance of the pasture signature and its stabilization in these tissues. Four groups of 35 lambs were used over two years, i.e. lambs fed concentrate in-stall (L0) and lambs grazing alfalfa for 21d (L21), 42d (L42) and 63d (L63) before slaughter. No one tissue satisfactorily discriminated the four treatment groups, with ≤75% of lambs correctly classified. However, visible spectroscopy discriminated L0 from L21 + L42 + L63 lambs with an accuracy of 92.8%, 92.0%, and 85.3% lambs correctly classified on PF, DF and muscle, respectively, and discriminated L0 + L21 from L42 + L63 lambs with an accuracy of 90.1%, 76.5% and 92.3% on PF, DF and muscle, respectively. The pasture fingerprint or signature on the spectrum appeared in most lambs between 0 and 21d in PF and DF and between 0 and 42d in muscle. Pasture signature gradually stabilized with increasing time on pasture but was not entirely stabilized in any tissue within the range of grazing durations explored. These promising results need to be confirmed on larger datasets with different breeds and grazing conditions.

Carcass characteristics and meat evaluation of cattle finished in temperate pasture and supplemented with natural additive containing clove, cashew oil, castor oils, and a microencapsulated blend of eugenol, thymol, and vanillin

BACKGROUND

Forty crossbred steers were supplemented with different doses (from 0 control to 6000 mg/animal/day) of natural additive blend containing clove essential oil, cashew oil, castor oil, and a microencapsulated blend of eugenol, thymol, and vanillin for 80 days. Carcass characteristics, drip loss, and antioxidant activity were evaluated 24 h post mortem on longissimus thoracis, and the effects of aging (until 14 days) were evaluated for water losses (thawing/aging and cooking), texture, color, and lipid oxidation.

RESULTS

The use of the natural additive blend did not modify (P > 0.05) carcass characteristics but did, however, modify body composition (P < 0.05). Drip losses were unaffected by the treatments tested (P > 0.05). There was an observed quadratic effect (P < 0.05) on losses from thawing/aging on the first day of storage. Regarding the effects of natural additives on cooking losses, there was a quadratic effect (P < 0.05) among the treatments on day 7 of aging. Differences between days of aging were only observed with control treatment. Shear force was similar among treatments on days 1 and 7 of aging. On day 14 a linear effect (P < 0.05) was observed. Also, a linear effect (P < 0.05) appeared on meat lightness, meat from the control group being clearer on day 1. No changes were observed in redness among treatments or days of storage (P > 0.05). Yellowness was not modified by the treatments (P > 0.05)but only by the days of storage in control and the lowest dosage used.

CONCLUSION

The blend of natural additives has potential use in pasture feeding and could improve meat quality. However, doses should be adjusted. © 2021 Society of Chemical Industry.

How Management System Affects the Concentration of Retinol and α-Tocopherol in Plasma and Milk of Payoya Lactating Goats: Possible Use as Traceability Biomarkers

Simple Summary

The milk production systems in goats are mainly intensive and semi-extensive. In the former, the goats are housed and are fed a total mixed ration with vitamin supplementation. In the latter, the feeding of the goats is based on grazing, although with some supplementation with compound feed. Retinol and α-tocopherol that appear in these animals come from the feeding regime, since the animal cannot synthesize them. The objective of this study was to verify if the vitamins provided in different management systems of Payoya lactating goats are good markers of the production system. For this purpose, the content of carotenoids, retinol and α-tocopherol in the milk and plasma of the goats was quantified. Results showed an inverse relationship of the amount of these vitamins between milk and plasma. On the other hand, the metabolism of different vitamins depends on their origin (natural/synthetic), with natural α-tocopherol and synthetic retinol showing the highest amount in milk. Finally, it was found that these compounds can be good traceability tools which allows to guaranty to the consumer the origin of the products derived from these animals.

Abstract

The retinol and α-tocopherol concentrations were quantified (μg/mL) using high-performance liquid chromatography (HPLC) in both plasma and milk of goats from three management systems. The aim was to investigate if the compounds pass from feed to animals’ fluids and to evaluate their potential use as feeding regime biomarkers. A total of 45 Payoya dams were distributed in three groups according to management system during the first month of lactation: mountain grazing (MG), cultivated meadow (CM) and total mixed ration (TMR). TMR group had higher concentrations of retinol in both plasma (25.92 ± 3.61 at 30 days postpartum) and milk (8.26 ± 0.79 at 10 days postpartum), and they were also the unique animals whose milk contained detectable concentrations of α-tocopherol (3.15 ± 0.19 at parturition). However, MG and CM goats showed higher plasma concentrations of α-tocopherol (64.26 ± 14.56 and 44.65 ± 5.75 at 30 days postpartum, respectively). These results could imply differences in the bioavailability of supplemented vitamin A and natural β-carotene and between the natural/synthetic forms of α-tocopherol. An inverse relationship between the fluids (plasma/milk) in the contents of α-tocopherol and retinol was observed as lactation progressed. Since 80% of the animals were correctly classified using a discriminant analysis based on these vitamins, these compounds could be used as traceability biomarkers of feeding system, but further studies are necessary to know the possible passage to kid meat.

Health-Promoting Phytonutrients Are Higher in Grass-Fed Meat and Milk

While commission reports and nutritional guidelines raise concerns about the effects of consuming red meat on human health, the impacts of how livestock are raised and finished on consumer health are generally ignored. Meat and milk, irrespective of rearing practices, provide many essential nutrients including bioavailable protein, zinc, iron, selenium, calcium, and/or B12. Emerging data indicate that when livestock are eating a diverse array of plants on pasture, additional health-promoting phytonutrients—terpenoids, phenols, carotenoids, and anti-oxidants—become concentrated in their meat and milk. Several phytochemicals found in grass-fed meat and milk are in quantities comparable to those found in plant foods known to have anti-inflammatory, anti-carcinogenic, and cardioprotective effects. As meat and milk are often not considered as sources of phytochemicals, their presence has remained largely underappreciated in discussions of nutritional differences between feedlot-fed (grain-fed) and pasture-finished (grass-fed) meat and dairy, which have predominantly centered around the ω-3 fatty acids and conjugated linoleic acid. Grazing livestock on plant-species diverse pastures concentrates a wider variety and higher amounts of phytochemicals in meat and milk compared to grazing monoculture pastures, while phytochemicals are further reduced or absent in meat and milk of grain-fed animals. The co-evolution of plants and herbivores has led to plants/crops being more productive when grazed in accordance with agroecological principles. The increased phytochemical richness of productive vegetation has potential to improve the health of animals and upscale these nutrients to also benefit human health. Several studies have found increased anti-oxidant activity in meat and milk of grass-fed vs. grain-fed animals. Only a handful of studies have investigated the effects of grass-fed meat and dairy consumption on human health and show potential for anti-inflammatory effects and improved lipoprotein profiles. However, current knowledge does not allow for direct linking of livestock production practices to human health. Future research should systematically assess linkages between the phytochemical richness of livestock diets, the nutrient density of animal foods, and subsequent effects on human metabolic health. This is important given current societal concerns about red meat consumption and human health. Addressing this research gap will require greater collaborative efforts from the fields of agriculture and medicine.

A comprehensive review on carotenoids in foods and feeds: status quo, applications, patents, and research needs

Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agro-food and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/#tabs|Name:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.

Review: Authentication of grass-fed meat and dairy products from cattle and sheep

Meat and dairy products derived from grassland carry premium values and sensory and nutritional qualities that aroused much interest for authentication methods to guarantee grassland origin claims. This article reviews the current state of knowledge on the authentication of meat and dairy of grassland origin from food analysis in both cattle and sheep. A range of methods alone or combined, involving analysis of elemental or molecular constituents of food product and fingerprinting profiling combined with chemometrics, have been developed and proved useful to differentiate contrasted feeding regimes and authenticate grass-fed meat and dairy. Their robustness and discriminatory reliability in more complex feeding conditions, such as in the case of dietary switches or when grass only makes up part of the animal's diet, are under active investigation. Our review highlights the possibilities and limitations of these methods, the latter being chiefly posed by variations in the quantity, characteristics and composition of grassland feedstuffs consumed by animals, which are nevertheless inherent to grassland-based production systems, variations in animal responses within and across breeds, and difficulties in detecting the consumption of non-grass feedstuffs by the animal. It also highlights a number of issues for consideration, points of caution and caveats in applying these methods. Scientists agree that much of the research carried out so far has been a 'proof of concept' type and that efforts should be made in the future to develop more databases to help gain genericity and robustness.

Reliability of visible reflectance spectroscopy in discriminating between pasture and stall-fed lambs from thin and fat-tailed sheep breeds in dry and hot environment

Considering the additional market value of pasture meat, many authentication methods were developed to discriminate it from meat produced in conventional systems. The visible reflectance spectroscopy technique has proved its efficiency under European conditions and breeds. The present study tested the reliability of this method to discriminate between pasture-fed (P) and stall-fed (S) lambs under North African conditions and investigated the effect of feeding system (FS) (P v. S) and breed (Barbarine; Queue Fine de l'Ouest; and Noire de Thibar) on weight and colour of perirenal, subcutaneous and caudal fat. A total of 18 P and 18 S lambs were used with 6 P and 6 S lambs for each breed. The colour and the reflectance spectrum of different fat tissues were measured. The FS affected weights of all fat tissues and all colour parameters of perirenal and subcutaneous fat (P ≤ 0.01); it almost affected redness and yellowness of caudal fat (P ≤ 0.05; P ≤ 0.01). In all adipose tissues, lightness was higher and both redness and yellowness were lower for S lambs than P lambs. The breed affected weight, lightness and redness of perirenal fat and weight and redness of subcutaneous fat with significant interaction with FS for subcutaneous fat data. To discriminate P lambs from S lambs, the reflectance spectrum of perirenal, subcutaneous and caudal fat at wavelengths between 450 and 510 nm (Method 1, M1) or at wavelengths between 400 and 700 nm using partial least squares discriminative analysis as a classification method (Method 2, M2) were used. M2 yielded to a higher proportion of correctly classified lambs compared with M1 (P = 0.001). The proportion of correctly classified lambs using M2 was 76.4, 75.0 and 80.0% for perirenal, subcutaneous and caudal fat for P lambs and 83.3, 76.4 and 100.0% for S lambs. Despite lower reliability in comparisons to European researches, this study confirmed the efficiency of visible reflectance spectroscopy technique applied on perirenal fat in feeding systems authentication under North African conditions and spotted the caudal fat as a new support for better classification of fat-tailed breeds.

Meat provenance: Authentication of geographical origin and dietary background of meat

The authenticity of meat is now an important consideration in the multi-step food chain from production of animals on farm to consumer consumption of the final meat product. A range of techniques, involving analysis of elemental and molecular constituents of meat, fingerprint profiling and multivariate statistical analysis exists and these techniques are evolving in the quest to provide robust methods of establishing the dietary background of animals and the geographical origin of the meat derived from them. The potential application to meat authentication of techniques such as stable isotope ratio analysis applied to different animal tissues, measurement in meat of compounds directly derived from the diet of animals, such as fatty acids and fat soluble vitamins, and spectroscopy is explored. Challenges pertaining to the interpretation of data, as they relate to assignment of dietary background or geographical origin, are discussed.

Comparison of visible and near infrared reflectance spectroscopy on fat to authenticate dietary history of lambs

Since consumers are showing increased interest in the origin and method of production of their food, it is important to be able to authenticate dietary history of animals by rapid and robust methods used in the ruminant products. Promising breakthroughs have been made in the use of spectroscopic methods on fat to discriminate pasture-fed and concentrate-fed lambs. However, questions remained on their discriminatory ability in more complex feeding conditions, such as concentrate-finishing after pasture-feeding. We compared the ability of visible reflectance spectroscopy (Vis RS, wavelength range: 400 to 700 nm) with that of visible-near-infrared reflectance spectroscopy (Vis-NIR RS, wavelength range: 400 to 2500 nm) to differentiate between carcasses of lambs reared with three feeding regimes, using partial least square discriminant analysis (PLS-DA) as a classification method. The sample set comprised perirenal fat of Romane male lambs fattened at pasture (P, n = 69), stall-fattened indoors on commercial concentrate and straw (S, n = 55) and finished indoors with concentrate and straw for 28 days after pasture-feeding (PS, n = 65). The overall correct classification rate was better for Vis-NIR RS than for Vis RS (99.0% v. 95.1%, P < 0.05). Vis-NIR RS allowed a correct classification rate of 98.6%, 100.0% and 98.5% for P, S and PS lambs, respectively, whereas Vis RS allowed a correct classification rate of 98.6%, 94.5% and 92.3% for P, S and PS lambs, respectively. This study suggests the likely implication of molecules absorbing light in the non-visible part of the Vis-NIR spectra (possibly fatty acids), together with carotenoid and haem pigments, in the discrimination of the three feeding regimes.

Response of lamb plasma carotenoid concentration to a shift from a low to a high dietary carotenoid level

This study was conducted to investigate the pattern of plasma carotenoid concentration (PCC) in lambs switching from a low to a high dietary carotenoid level. A total of 12 Romane lambs were individually penned indoors and fed a low dietary carotenoid level for 23 days (period 1) and then a high dietary carotenoid level for 15 days (period 2). At the beginning of period 2, the lambs were 15 weeks old and weighed 29.9 kg (s.d. 2.7) on average. Lambs were fed daily (dry matter) 0.558 kg alfalfa pellets, 0.181 kg straw and 0.181 kg barley. Plasma content of total carotenoids was measured daily in period 2 by spectrophotometry. PCC (μg/l) varied with the animal (P < 0.001) and with time elapsed since the beginning of alfalfa distribution (P < 0.001). Mean PCC was 8 μg/l (s.d. 3.3) at the beginning of period 2, then increased curvilinearly with the time elapsed since the beginning of alfalfa distribution. As early as 24 h on the alfalfa diet, PCC was already higher than before the switch (P < 0.001). Mean PCC continued to increase until day 6 on average and reached a plateau thereafter. We propose a monomolecular function to model this pattern, the equation obtained on the mean data being: PCC = 97 (s.e. 2.2) × (1-exp(-0.3378 (s.e. 0.0282)×d)), where r2 = 0.997, r.s.d. = 4.47, n = 15 and d = day. The percentage of variance explained by the model ranged between 95.9% and 99.2%, depending on the animal. The parameters of the monomolecular function varied among animals, confirming the interindividual variability in animal response. Plateau for PCC was reached slightly earlier for the six lambs with the lowest values of the asymptote than for the six lambs with the highest values of the asymptote.

Fat spectro-colorimetric characteristics of lambs switched from a low to a high dietary carotenoid level for various durations before slaughter

This study investigated the changes in fat reflectance spectrum characteristics and color in lambs switched from a low to a high dietary carotenoid level for various durations before slaughter. Six treatments, feeding a high dietary carotenoid level for 0, 15, 30, 45, 60 or 75 days before slaughter, were compared in individually indoor penned lambs. Each treatment used 10 Romane lambs; feeding management ensured similar growth pattern and carcass weight for all the treatment groups. There was a change in reflectance spectrum characteristics and yellowness of subcutaneous fat as early as 15 days after the switch. Mean concentration of carotenoid pigments and yellowness of subcutaneous fat increased linearly with the duration of the high dietary carotenoid level. In perirenal fat, the change in reflectance spectrum characteristics was observed as early as 15 days after the switch, but the response to the duration of the high dietary carotenoid level was curvilinear.

The Effect of a Protein-Xanthophyll Concentrate from Alfalfa (Phytobiotic) on Animal Production - A Current Review

One of the supplements that can replace antibiotic growth promoters is a protein xanthophyll extract from the leaves of alfalfa. Green matter of alfalfa contains 17-22% of total protein, rich in non-essential (exogenous) amino acids, saturated, monounsaturated and polyunsaturated fatty acids, vitamins, minerals, and organic acids. The crude fibre content in green matter of alfalfa is relatively high (about 23.0-30.0% dry weight). However, protein-xanthophyll extract (EFL) contains about 1-2% of crude fibre. Like the whole plants of alfalfa, the protein-xanthophyll extract contains secondary metabolites such as plant phytoestrogens (isoflavones and coumestrol) and antinutritional components (phytates, L-canavanine and saponins). Protein-xanthophyll concentrate (PX) as a natural feed supplement has a positive effect on animal organisms. When supplemented to animals, this extract enhanced production results, increased feed efficiency, and improved the quality of meat, milk and eggs. Also, PX reduced methane emissions and soil pollution with nitrogen compounds when used in animal nutrition. The aim of this review was to gather the current literature describing the effects of using protein-xanthophyll extract in animal nutrition.

Influence of alfalfa grazing-based feeding systems on carcass fat colour and meat quality of light lambs

One hundred and twenty-seven lambs were fed as follows: lambs and dams grazing alfalfa (Gr); the same as Gr but lambs had access to concentrate (Gr + S); ewes grazed and lambs received milk and concentrate until weaning and thereafter concentrate and straw (Rat-Gr); ewes and lambs were stall-fed (Ind). Lambs were slaughtered at 22-24 kg live weight and fat and M. rectus abdominis colour was measured instrumentally and subjectively. The evolution of the instrumental colour and texture of M. longissimus lumborum was also recorded. There were significant differences in the instrumental colour of subcutaneous fat amongst feeding systems, but no differences were observed upon visual appraisal. On average, M. rectus abdominis colour in the four feeding systems was classed as pink. Differences in longissimus thoracis colour at 0 h disappeared at 24h of air exposure and there were no differences in pH or cooking losses. At no time were any differences in instrumental texture found.

β-Cryptoxanthin- and α-carotene-rich foods have greater apparent bioavailability than β-carotene-rich foods in Western diets

β-Carotene (BC), β-cryptoxanthin (CX) and α-carotene (AC) are common carotenoids that form retinol. The amount of retinol (vitamin A) formed from carotenoid-rich foods should depend chiefly on the bioavailability (absorption and circulation time in the body) of carotenoids from their major food sources and the selectivity and reactivity of carotene cleavage enzymes towards them. The objective of the present study was to estimate the apparent bioavailability of the major sources of provitamin A (AC, BC and CX) from the diet by comparing the concentrations of these carotenoids in blood to their dietary intakes. Dietary intakes were estimated by FFQ (three studies in this laboratory, n 86; apparent bioavailability calculated for six other studies, n 5738) or by food record (two studies in our laboratory, n 59; apparent bioavailability calculated for two other studies, n 54). Carotenoid concentrations were measured by reversed-phase HPLC. Apparent bioavailability was calculated as the ratio of concentration in the blood to carotenoid intake. Then apparent bioavailabilities for AC and CX were compared to BC. Eating comparable amounts of AC-, CX- and BC-rich foods resulted in 53 % greater AC (99 % CI 23, 83) and 725 % greater CX (99 % CI 535, 915) concentrations in the blood. This suggests that the apparent bioavailability of CX from typical diets is greater than that of BC. Thus, CX-rich foods might be better sources of vitamin A than expected.

Latency and persistence of diet volatile biomarkers in lamb fats

Several studies have shown that volatile compounds are particularly well-suited for the authentication lamb diet by gas chromatography-mass spectrometry (GC-MS) analysis of adipose tissue. The aim of the present work was to use dynamic headspace-GC-MS to study the variations in the amounts of volatile diet tracers in perirenal fat (PRF) and caudal subcutaneous fat (CSCF) in lambs (n = 24) that were fed with concentrate and then allowed to graze for 0, 17, 51, or 85 days. Twenty-six volatile compounds were found to distinguish between the four diets (p < 0.05) in both PRF and CSCF. Of these diet tracers, 16 were found to be related to the pasture diet and increased at different rates according to the time spent at pasture (latency), while 10 were found in higher amounts in tissues of lambs fed with exclusive concentrate and exhibited different rates of clearance (persistence). Twenty-four of these discriminant compounds, including alkanes, ketones, terpenes, and 2,3-octanedione, were previously stated as pasture diet tracers in several earlier studies, suggesting their potential universality. All degrees of latency or persistence were exhibited by the pasture and concentrate diet tracers, respectively. A principal component analysis performed on ratios of selected diet tracers from both adipose tissues evidenced successful differentiation of the four feeding situations.