Podolian Bulls Research Articles

Effects of dietary extruded linseed (<i>Linum usitatissimum</i> L.) on performance and meat quality in Podolian young bulls

This study compared effects of a diet containing 3% extruded linseed (EL) (Linum usitatissimum L.) with a control diet (C) on growth, carcass traits, and meat quality in young Podolian bulls. After 208 days on feed, the bulls were slaughtered at 18 months of age. Samples of Longissimus lumborum (Ll) were analysed to assess their physical and chemical parameters and intramuscular fatty acid composition. Average daily gain, feed intake and feed efficiency were not affected by treatments. Bulls fed EL (n = 6) had significantly greater final (612 kg versus 593 kg) and slaughter weights (583 kg versus 563 kg) than those fed C (n = 6). Compared with C, EL significantly increased percentages of lean from the pelvic limb (71.9% versus 69.3%) and of bone from the lumbar region (30.0 versus 27.1%). Meat pH recorded at slaughter was significantly greater for C than EL (6.7 versus 6.4). Diet did not affect meat colour, chemical composition and shear force of either the raw or cooked meat. Total amounts of saturated, monounsaturated and polyunsaturated fatty acids were not influenced by the diets. Concentrations of linoleic acid (C18:2 n-6) (3.30 versus 4.08) and total n-6 fatty acids (3.83 versus 4.73) were reduced by EL, while EL significantly enhanced linolenic acid (C18:3 n-3) (0.45 vs 0.20) and total n-3 fatty acids (1.64 versus 1.18) in the meat compared with C. Thus, dietary supplementation with 3% EL improved the amount of n-3 fatty acids in the meat from young Podolian bulls without affecting their performance.Keywords: carcass traits, fatty acids, feed efficiency, growth, meat colour

Eating quality of beef from free-range and confined Podolian young bulls1,2

The purpose of the present study was to assess the effect of grazing on meat quality of young Podolian bulls by using 6 free-ranging (FR) and 6 confined (CON) animals slaughtered at 18 mo of age (Exp. 1). A second experiment (Exp. 2) was performed the subsequent year where the age at slaughter was 15 mo of age (6 animals/group). Quantitative descriptive sensory analysis, water-holding capacity (WHC; thawing, centrifugation, and cooking losses), and shear force (only in Exp. 2) were evaluated on LM, aged 8 d. Both experiments showed that CON animals produced beef with greater overall beef flavor (P < 0.01 and P < 0.05 in Exp. 1 and 2, respectively) and odor intensities (P < 0.10 and P < 0.05 in Exp. and 1 and 2, respectively) and increased malondialdehyde contents (P < 0.01 and P < 0.05 in Exp. 1 and 2, respectively). In Exp. 2 beef from FR bulls showed higher sensory tenderness as compared with CON bulls (P < 0.05) and a lower shear force (P < 0.05). In Exp. 1, beef obtained from FR bulls showed lower centrifugation and greater thawing losses compared with samples from bulls from group CON (P < 0.05) whereas rearing system did not affect any WHC variables in Exp. 2. The results obtained from the 2 experiments were generally consistent. The different results occasionally observed (e.g., sensory tenderness and WHC) is attributed to the different ages at slaughter used in the 2 experiments (18 and 15 mo). In particular, at an earlier age at slaughter (15 mo) the effect of FR on meat quality was beneficial on sensory tenderness and mechanical properties. Therefore, given the additional costs of maintaining the bulls for another 3 mo when slaughtered at 18 mo of age, a reduced age at slaughter of FR bulls may be suggested to avoid the decrement of herbage mass availability inducing the consumption of high amounts of concentrate.

Effect of grazing and dietary protein on eating quality of Podolian beef1,2

Twenty-four young Podolian bulls were used to evaluate the effect of rearing system (extensive vs. intensive) in relation to postmortem aging (11 and 18 d) on the eating quality of the meat, with the diet of outdoor animals adjusted to the protein content of the indoor system (15% CP) or to the minimum protein content required for satisfactory growth (12% CP). At 415 ± 9.35 (SE) d of age, with a mean BW of 337.5 ± 16.51 (SE) kg, animals were allotted to 3 groups for the finishing period (172 d): 1) indoor group receiving a diet at 15% CP; 2) grazing animals receiving a diet at 15% CP of DM; and 3) grazing animals receiving a diet at 12% CP of DM. Longissimus dorsi lumborum muscle sampled from the right half and divided longitudinally into 2 sections was aged in vacuum packaging at 4°C until 11 and 18 d postmortem, respectively. Rearing system did not affect (P > 0.05) color, Warner-Bratzler shear force, texture profile, water-holding capacity, and most of the sensory attributes of the beef steaks. However, sensory tenderness was less in the meat from outdoor animals receiving a diet with 15% CP than in meat from outdoor animals receiving a diet with 12% CP or from the indoor group (P < 0.05). Meat aged 18 d showed decreased Warner-Bratzler shear force (P < 0.001), hardness (P < 0.001), cohesiveness (P < 0.05), springiness (P < 0.05), gumminess (P < 0.01), chewiness (P < 0.01), and thawing loss (P < 0.01) compared with meat aged for 11 d. Prolonging the aging time up to 18 d significantly increased b* (yellowness; P < 0.05), cooking losses (P < 0.001), and the intensity of all the texture sensory attributes, namely, juiciness and fatness (P < 0.05), chewiness, tenderness, and flavor (P < 0.01). Significant correlations were found between instrumental and sensory variables (range of r = -0.55 to -0.85, P < 0.05 to 0.001). Overall, in the present study, the rearing system did not markedly affect meat sensory and physical properties. Thus, we conclude that an outdoor system, even with reduced protein supplementation, may represent a valid farming system for local breeds in Mediterranean areas characterized by poor-quality pastures. However, an extended aging period is suggested to improve the main factor limiting the quality of this product, namely, reduced tenderness.

Effect of rearing system and of dietary protein level on leptin, growth, and carcass composition in young Podolian bulls

The present study aimed to evaluate the effects of rearing system and level of dietary protein supplementation on growth performance, metabolic profile, plasma leptin, and carcass composition of young Podolian bulls. At the beginning of the finishing period (about 14 mo of age), animals were divided into 3 groups according to rearing system and dietary protein level: indoor receiving a diet with 15% CP of DM (IND); and outdoor, at pasture, receiving a supplementation with 12% CP of DM (OUT12) or with 15% CP of DM (OUT15). Plasma leptin concentration increased (P < 0.05) with age, whereas it was unaffected by rearing system and protein level. Positive correlations between plasma leptin concentration, ADG (r = 0.861, P < 0.001), and blood glucose concentration (r = 0.977, P < 0.001) were observed, whereas NEFA and triglycerides were not correlated with leptin concentration. At the end of the finishing period (about 20 mo of age), young bulls in the OUT12 group showed greater (P < 0.05) cholesterol concentrations in blood than the OUT15 group, whereas the OUT15 group showed greater urea concentrations compared with IND (P < 0.01) and OUT12 groups (P < 0.001). Average daily gains, feed conversion ratio, and final BW were similar between groups. Intramuscular lipid content of LM, semitendinosus, and semimembranosus muscles was correlated with plasma leptin before slaughtering (r = 0.77, P < 0.01; r = 0.67, P < 0.01, r = 0.79, respectively). Correlations between plasma leptin and intramuscular fat were found starting from 18 mo of age for LM (r = 0.44; P < 0.05) and from 19 mo for semimembranosus (r = 0.56; P < 0.05) and semitendinosus (r = 0.58; P < 0.05). Mean value of intramuscular fat and intramuscular fat of LM was greater in OUT15 than OUT12 (P < 0.05). No differences were found between 12 and 15% CP supplementations for growth and carcass data. Therefore, we conclude that the extensive rearing system supplemented with 12% CP may be adequate to sustain good growth performance and carcass quality from the Podolian breed. These data also provide confirmation that leptin, in cattle, is directly related to nutritional status and may represent a suitable predictor for body fat starting from 1 mo before slaughtering.

Chemical, physical and sensory properties of meat from pure and crossbred Podolian bulls at different ageing times

The present study aimed to investigate the effect of crossbreeding with Limousine sires on fatty acid profile, physical and sensory properties of meat produced by Podolian young bulls. Polyunsaturated fatty acid content was influenced by crossbreeding ( P < 0.01) with Podolian bulls (P) producing beef characterised by a higher level of unsaturation in comparison with crossbred animals (LP). As a consequence, P/S ratio was significantly higher in meat produced by P animals than LP ( P < 0.01). P animals had higher linoleic ( P < 0.05), linolenic ( P < 0.05), EPA ( P < 0.05) and DHA acids ( P < 0.001) levels than LP subjects. No breed effect was observed for the ratio n − 6/ n − 3 ( P > 0.05). WBS force of LD was significantly lower in meat from crossbred subjects ( P < 0.05). Both crossbreeding with Limousine and extension of ageing from 2 to 7 days improved LD tenderness as assessed by panel taste ( P < 0.001).