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[Background]: Deer-meat consumption is increasing in several countries based on claims that it is a healthy red meat. This study assessed the effect of slaughter age (low – 26 months and younger; medium – from 27 months to younger than 42 months; and high – 42 months and older) on carcass characteristics and meat physicochemical properties of 150 Iberian wild red deer., [Results]: Whole carcass yields of neck, backbone and flank increased (P < 0.001) with age, while yields of shoulder, tenderloin and leg decreased (P < 0.05) with age. The pH measured at 48 h post mortem at 9th rib level was not affected by age, while pH measured at 72 h post mortem at the longissimus thoracis et lumborum muscle decreased (P < 0.05) with age. Meat chemical composition was not affected by slaughter age, except for intramuscular fat (IMF), which increased (P < 0.05) with slaughter age. Finally, cooking loss and shear force were higher (P < 0.05) in meat from older deer., [Conclusion]: Most characteristics of meat from wild red deer depend on age at slaughter. The greater IMF of meat from older animals may render it more palatable. However, meat shear force also increased with age. Additional studies testing palatability seem to be necessary to evaluate the effects of slaughter age on the sensorial quality of meat from Iberian wild red deer.

Supplementation with copper (Cu) improves deer antler characteristics, but it could modify meat quality and increase its Cu content to levels potentially harmful for humans. Here, we studied the effects of Cu bolus supplementation by means on quality and composition of sternocephalicus (ST) and rectus abdominis (RA) muscles (n=13 for each one) from yearling male red deer fed with a balanced diet. Each intraruminal bolus, containing 3.4 g of Cu, was administered orally in the treatment group to compare with the control group. Meat traits studied were pH at 24 h postmortem (pH24), colour, chemical composition, cholesterol content, fatty acid (FA) composition, amino acid (AA) profile and mineral content. In addition, the effect of Cu supplementation on mineral composition of liver and serum (at 0 and 90 days of treatment) was analysed. No interactions between Cu supplementation and muscle were observed for any trait. Supplementation with Cu increased the protein content of meat (P<0.01). However, Cu content of meat, liver and serum was not modified by supplementation. In fact, Cu content of meat (1.20 and 1.34 mg/kg for Cu supplemented and control deer, respectively) was much lower in both groups than 5 mg/kg of fresh weight allowed legally for food of animal origin. However, bolus of Cu tended to increase the meat content of zinc and significantly increased (P<0.05) the hepatic contents of sodium and lead. Muscles studied had different composition and characteristics. The RA muscle had significantly higher protein content (P<0.001), monounsaturated FA content (P<0.05) and essential/non-essential AA ratio (P<0.01) but lower pH24 (P<0.01) and polyunsaturated FA content (P=0.001) than the ST muscle. In addition, RA muscle had 14.4% less cholesterol (P=0.001) than ST muscle. Also, mineral profile differed between muscles with higher content of iron, significantly higher (P<0.001) content of zinc and lower content of calcium, magnesium and phosphorus (P<0.05) for ST muscle

Antlers are bony appendages of deer that undergo periodic regeneration from the top of permanent outgrowths (the pedicles) of the frontal bones. Of the “less familiar” bone types whose study was advocated by John Currey to gain a better understanding of structure-function relationships of mineralized tissues and organs, antlers were of special interest to him. The present review summarizes our current knowledge about the evolution, development, structure, mineralization, and biomechanics of antlers and how their formation is affected by environmental factors like nutrition. Furthermore, the potential role of antlers as a model in bone biology and several fields of biomedicine as well as their use as a monitoring tool in environmental studies are discussed.

Antler growth is a costly yearly process supplied by daily nutrition and body reserves. Conditions for antler growth are rarely optimal. Thus, certain decrease in antler quality due to depletion of resources, known as physiological exhaustion, is frequently observed along the main beam. Testosterone promotes the mineralization in the last phase of antler growth, and its concentration change in male deer according to the socio-sexual environment: it is greater in single males housed only with females than in males housed only with other males (female effect). We hypothesised that the socio-sexual environment affect antler mineralization; especially in the top of the antler which is the last part mineralising and subjected to the described physiological exhaustion, but also the one mineralising when testosterone levels are higher. We tested this in antlers of pampas deer (Ozotoceros bezoarticus) from captive animals living in the two social contexts described. All the animals had an ad libitum high nutrition plan, so results are not due to nutritional differences. The antlers from males living with females suffered a lower physiological exhaustion (i.e., lower percent decrease in the top compared to the base of the antler) in the two most important minerals: Ca and P, but also similar tendencies in other bone-biology related trace elements like Sr and Li. Our results highlight that the socio-sexual environment, particularly living continuously in close contact with females, promotes antler mineralization probably through modifications in testosterone secretion.

In the present study we assessed the effects of Cu supplementation and antler growth stage on mineral composition of serum and hard antler in red deer fed a balanced diet. Correlations between minerals were analysed for serum, for antlers, and between serum versus mature antler. Blood samples were drawn at Days –36, 54, 132 and 197 of the start of antler growth (SAG). Hard antlers were cut at Day 165 from SAG. The Cu supplemented group (n = 9) was injected with 0.83 mg Cu/kg of bodyweight, whereas the control group (n = 9) was injected with a physiological saline solution, both every 42 days between Days –36 (Cu supplied after blood sampling) and 132 from SAG. Supplementation with Cu increased (P < 0.05) the contents of P and Cu in serum but did not affect the antler mineral profile. Serum contents of Mg, Na, S, B and Cu increased during the antler growth, whereas contents of K, Al and Fe decreased in the same period (P < 0.001). At Day 54 from SAG in Cu group, serum P content correlated negatively with antler Ca content whereas Zn of serum and antler correlated positively (P < 0.05). The maximum number of correlations between the mineral profile of serum and hard antler was achieved at Day 132 from SAG (3.3, 4.7 and 12.9% for Days –36, 54 and 132, respectively). In conclusion, the analysis of specific minerals in serum could be used to detect in advance some mineral deficiencies in the antler.

[Background]: This study assessed the effect of age (L, less than 27 months old; M, from 27 to 42 months old; H, 43 months and older) on the fatty acid profile, cholesterol content, amino acid composition and mineral content of 150 Iberian wild red deer meat samples., [Results]: Intramuscular fat content increased (P < 0.05) with age (0.05 vs 0.12 vs 0.34% for L, M and H groups respectively), while cholesterol content decreased (P < 0.05) as the slaughter age increased (52.78 vs 48.72 vs 45.34 mg per 100 g meat for L, M and H groups respectively). The slaughter age showed differences among groups for saturated fatty acids, with the highest content in older animals (30.41 vs 34.55 vs 38.21% for L, M and H groups respectively), whereas younger deer displayed the highest polyunsaturated fatty acid levels (50.05 vs 45.24 vs 37.55% for L, M and H groups respectively). The n ‐6/n ‐3 ratio was more favorable (P < 0.05) for young and medium ages compared with that for older animals. In contrast, amino acid profile and mineral content were only slightly affected by age., [Conclusion]: As a general conclusion, wild red deer meat could be considered a good alternative to red meats for human consumption.

Hydrogels present versatile platforms for the encapsulation and delivery of proteins and cells for regenerative medicine applications. However, differences in hydrogel cross-linking density, polymer weight content, and affinity for proteins all contribute to diverse diffusion rates of proteins through hydrogel networks. Here, we describe a simple method to accurately measure protein diffusion through hydrogels, within a few hours and without the use of large amounts of protein. We tracked the diffusion of several proteins of varying molecular weights along the axial direction of capillary tubes filled with alginate, collagen, or poly(ethylene glycol) hydrogels. The rate of protein diffusion decreased with increasing molecular weight. A computational model of protein diffusion through capillary tubes was also created to predict and verify experimental protein diffusion coefficients. This in vitro capillary tube-based method of measuring protein diffusion represents a simple strategy to interrogate protein diffusion through natural and synthetic hydrogels and aid in the design of better biomaterial-based delivery vehicles that can effectively modulate protein release.

The use of human mesenchymal stromal cells (hMSC) for treating diseased tissues with poor vascularization has received significant attention, but low cell survival has hampered its translation to the clinic. Bioglasses and glass-ceramics have also been suggested as therapeutic agents for stimulating angiogenesis in soft tissues, but these effects need further evaluation in vivo. In this study, calcium-releasing particles and hMSC were combined within a hydrogel to examine their vasculogenic potential in vitro and in vivo. The particles provided sustained calcium release and showed proangiogenic stimulation in a chorioallantoic membrane (CAM) assay. The number of hMSC encapsulated in a degradable RGD-functionalized PEG hydrogel containing particles remained constant over time and IGF-1 release was increased. When implanted in the epidydimal fat pad of immunocompromised mice, this composite material improved cell survival and stimulated vessel formation and maturation. Thus, the combination of hMSC and calcium-releasing glass-ceramics represents a new strategy to achieve vessel stabilization, a key factor in the revascularization of ischemic tissues. Statement of Significance: Increasing blood vessel formation in diseased tissues with poor vascularization is a current clinical challenge. Cell therapy using human mesenchymal stem cells has received considerable interest, but low cell survival has hampered its translation to the clinic. Bioglasses and glass-ceramics have been explored as therapeutic agents for stimulating angiogenesis in soft tissues, but these effects need further evaluation in vivo. By incorporating both human mesenchymal stem cells and glass-ceramic particles in an implantable hydrogel, this study provides insights into the vasculogenic potential in soft tissues of the combined strategies. Enhancement of vessel formation and maturation supports further investigation of this strategy., Peer Reviewed, Postprint (published version)

Horns are permanent structures projecting from the head of bovids, consisting of a bony horncore covered with a layer of skin and then a sheath of keratinous material showing variability of growth intensity based on nutrition. From the point of view of the horn's mechanical properties, the keratin sheath has been widely studied, but only a few studies have considered the complete structure of the horn and fewer studies have focused on the bony horncore and its characteristics. The latter showed the important role of the bony core, when cranial appendages are subject to mechanical stress (as happens during fighting). The mechanical properties of bone material, along with its mineral profile, are also important, because they can show effects of different factors, such as nutrition and mineral deficiencies in diet. For this reason, eight horncores of captive common eland male were sampled at four positions along the vertical axis of the horn. The main aim was to study variation in mechanical properties and the mineral content along the vertical axis of the horncores. We further analysed whether the spiral bony ridge present on eland horncores differs in any of the studied properties from adjacent parts of the horncore. In other antelopes, spiral ridges on the horns have been proposed to increase grip during wrestling between males. Cross-sections of the horncores were performed at four positions along the longitudinal axis and, for each position, two bone bars were extracted to be tested in impact and bending. Moreover, in the first sampling position (the closest position to the base) two bars were extracted from the spiralled bony area. The resulting fragments were used to measure ash content, bone density and mineral content. Results showed that horn bone decreased along the vertical axis, in ash (−36%), density (−32%), and in impact work ‘U’ (marginally significant but large effect: −48%). The concentration of several minerals decreased significantly (Mg, Cr, Mn and

We studied the effects of social rank on the haematologic profile in a herd of 24 female Iberian red deer hinds. Social rank hierarchy was determined and blood samples were taken and analysed. After adjusting for age and body mass, dominance ranking showed a significant negative effect (ie, lower values in dominant hinds) on white blood cell (WBC) count, haemoglobin and haematocrit. Our results are similar to those reported for stressed individuals due to physical immobilisation, but do not support the predicted enhanced erythropoiesis due to higher levels of androgens. The results for WBC numbers may also reflect that subordinate hinds must allocate a higher amount of resources to immunity as a result of injuries incurred from dominant hinds, while simultaneously facing restricted access to food sources. For red blood cell (RBC) counts, the results may be due to subordinate hinds likely needing increased haematocrit and haemoglobin levels for fast flight responses. Our data show that social rank influences haematologic profile, and thus it should be considered when correctly interpreting blood analyses in social cervid species.

This study describes the effects of Mn supplementation of 20 late-gestating and lactating Iberian red deer (Cervus elaphus hispanicus) females (hinds) fed a balanced diet on milk production and milk composition over the lactation period. Body weight of their calves at birth and at weaning was also evaluated. In addition, the effect of lactation stage was studied. For these purposes, 2 groups of hinds, one composed by 12 individuals (experimental) and the other by 8 individuals (con-trol) were compared. Experimental hinds were s.c. injected weekly with Mn (2 mg Mn/kg BW) from day 140 of gestation until the end of lactation (week 18; forced weaning by physical separation). Control hinds were injected with a physiological saline solution with the same volume and at the same frequency as the experimental group. Serum Mn content of hinds was assessed just before the first Mn injection and at week 10 of lactation to assess whether the injected Mn increased Mn concentrations in blood. No differences were observed for BW of calves at birth but calves whose mothers were injected with Mn tended (P = 0.07) to have greater gain of BW from birth to weaning in proportion of BW at birth compared to calves from control hinds. In addition, supplementation with Mn increased (P ≤ 0.05) daily milk production by 10.2%, milk fat content by 11.2%, and total fat yield by 17.8%. Also, milk from hinds supplemented with Mn had more Ca (P < 0.001) and P (P < 0.05) than milk from control hinds. Manganese supplementation did not influence Mn serum content when blood was analyzed at week 10 of lactation, but increased the Mn content of milk by 18.3% (P < 0.001). Lactation stage affected (P < 0.001) fat, protein, lactose, and DM. Their contents increased as lactation proceeded, and protein was substituted by fat. Therefore, results suggest that Mn supplementation of hinds is recommended, even when they are fed a balanced diet, to increase milk production and the content of fat, Ca, P, and Mn of mi

[Objectives]: Studying animal vocal aging has potential implication in the field of animal welfare and for modeling human voice aging. The objective was to examine, using a repeated measures approach, the between-year changes of weight, social discomfort score (bites of other hinds on hind pelt), body condition score (fat reserves) and acoustic variables of the nasal (closed-mouth) and the oral (open-mouth) contact calls produced by farmed red deer hinds (Cervus elaphus) toward their young. [Results]: Repeated measures ANOVA revealed that with an increase of hind age for 1 year, the acoustic variables of their nasal contact calls (the beginning and maximum fundamental frequencies, the depth of frequency modulation and the peak frequency) decreased, whereas in their oral contact calls only the end fundamental frequency decreased. Duration and power quartiles did not change in any call type. Body weight and body condition score increased between years, whereas discomfort score decreased. Results of this study revealed directly the short-term effects of aging on the acoustics of the nasal contact calls in the same hinds. This study also confirmed that elevated emotional arousal during emission of the oral contact masks the effects of aging on vocalization in female red deer.