Elena Saccà

Effect of linseed addition on the expression of some lipid metabolism genes in the adipose tissue of young Italian Simmental and Holstein bulls

The objective of this trial was to determine the effect of breed and long-term dietary linseed addition on composition of fatty acids and expression of some genes involved in the lipid metabolism within subcutaneous (s.c.) adipose tissue of young bulls. Italian Simmental and Holstein bulls (n=16/breed) were fed a corn silage-grass hay diet with or without 8% (DM basis) whole ground linseed. Inclusion of linseed, rich in α-linoleic acid (C18:3n-3), increased (P<0.05) the proportions of linolelaidic (C18:2n-6trans), γ-linolenic (C18:3n-6), C18:3n-3, and rumenic (cis9,trans11 conjugated linoleic acid) acids, as well as total n-3 fatty acid, total PUFA, and PUFA:SFA, but decreased (P<0.05) weight percentages of myristic (C14:0), pentadecanoic (C15:0), palmitic (C16:0), palmitelaidic (C16:1n-9trans), and margaric (C17:0) acids, along with n-6:n-3, in the s.c. fat of young bulls. Even though PUFA were similar (P≥0.23) between bull breeds, s.c. fat from Holstein bulls had greater (P<0.05) proportions of tridecylic (C13:0), myristoleic (C14:1) and palmitoleic (C16:1n-9cis) acids and a lower (P<0.05) proportion of margaric (C17:0) acid than s.c. fat from Simmental bulls. Feeding linseed decreased (P<0.05) the expression of stearoyl CoA desaturase (SCD) and the lipoprotein lipase (LPL) gene without affecting (P≥0.19) fatty acid synthase (FASN), leptin (LEP), and PPARγ2 mRNA in the s.c. fat of bulls; however, there was no effect of bull breed (P≥0.11) or interactive effect of breed and linseed (P≥0.23) on gene expression. Expression of PPARγ2 was positively correlated with SCD (r=0.454; P=0.01), LEP (r=0.500; P<0.01), and LPL (r=0.531; P<0.01) mRNA, indicating that PPARγ2 increases the expression of genes involved in lipogenesis.

Effects of stocking density and supplement level on milk production and cheese characteristics in Brown cows grazing on mountain pasture.

Twenty-eight Brown cows were maintained on a mountain pasture for a period of 40 days and assigned to 4 groups following a factorial design 2 stocking density (0.7 and 1.4 cows/ha)x2 supplement levels (2.4 and 4.8 kg organic matter (OM)/d). Herbage intake, animal body condition score (BCS), milk yield, milk chemical and coagulation properties, cheese composition, rheology and sensory characteristics were measured. The average herbage intake was 12.2 kg OM/d, with a significant effect related to stocking density (low, 13.1 v. high, 11.4 kg OM/d). BCS variation was always negative and changed with supplement level, although with no statistical significance (-0.43 points on average). Milk yield was lower for the group with lower availability of herbage (low supplement and high stocking density: 15.9 kg/d), whereas it was comparable among others groups (16.9 kg/d on average). The group with high supplement and low stocking density produced milk with worse cheese making properties. Cheese composition analyses showed an effect of supplement level on calcium content, and on parameters for degree of ripening, such as nitrogen fractions and lipolysis index. As for the textural parameters, hardness and gumminess were found to be higher with the low level of supplement. The different level of supplementation could differentiate the groups on the basis of the sensory perception of cheese.

Effect of type and level of supplement on performance of dairy cows grazing on alpine pasture

Abstract An experiment was carried out on 32 dairy cows (average yield 21.9 ± 2.7 kg/d) grazing on summer alpine pasture, in order to examine the effect of two types of supplement - Starchy (42% of cereal) and Fibrous (41% of beet pulp) - both provided at two different levels - Low (1 kg of supplement per 5.0 kg of energy corrected milk (ECM)) and High (1 kg of supplement per 3.3 kg of ECM) - on herbage intake, milk yield and quality. The supplement was distributed twice a day, during milking, at a constant level throughout the experiment (July and August), as calculated according to the daily milk yield in a one-week preliminary period. Meteorological measurements, herbage quality and availability, herbage intake, animal body condition score (BCS), milk yield, chemical and rheological traits were determined. The herbage intake was higher (11.9 kg organic matter (OM)/d) with the Fibrous supplement at Low level. Even if the supplementation covered up to one third of the total intake of OM, none of the experimental groups increased BCS, and the Starchy-Low group showed a decrease in BCS significantly different from zero. The increase in the level of supplementation (from 3.5 to 5.0 kg OM/d in Low and High groups, respectively) improved the ECM yield by an average of 1.2 kg/d (P<0.05), without significant changes in the chemical composition of the milk, while the supplement type had no significant effects on either milk yield or composition. The mean coagulation properties were better with the Fibrous supplement as compared to the Starchy one – rennet clotting time (r): 16’24’’ vs 19’15’’ (P<0.05), time for aggregation (K20): 5’03’’ vs 6’45’’ (n.s.), gel firmness (a30): 26.1 mm vs 20.8 mm (P<0.05) - without significant differences derived from the level of supplementation.

Variability in the characteristics of fresh meat and thighs in relationship to genetic type of the heavy pig

Abstract The variability in the characteristics of fresh meat and thighs in relationship with genetic type was studied on 22 lots of heavy pigs, comprising 615 female and castrated males, randomly chosen during slaughtering in groups of 20 to 30 animals per lot. Four different genetic types reared for the production of the San Daniele dry-cured ham PDO were considered: two traditionals (Large White or Duroc x (Landrace x Large White) and two industrial hybrids (GOLAND and DANBRED). Fresh meat samples from longissimus dorsi muscle were collected to perform chemical and physical analysis. The right trimmed thighs were used to evaluate some morphological parameters along with weight losses during seasoning. The genetic type confirmed its important influence on pig carcass, meat and ham quality. The two industrial types, DANBRED in particular, tended to present a lower back fat values and a leaner carcass than the two Italian genetic types. Within the most important characteristics for the production of dry cured hams (subcutaneous fat thickness and seasoning losses) the highest differences were found among the industrials genetic types, which cannot be simply considered as an undifferentiated homogenous group.

Assessment of calpain and caspase systems activities during ageing of two bovine muscles by degradation patterns of αII spectrin and PARP-1

The activities of calpain and caspase systems during ageing in Longissimus lumborum (LL) and Infraspinatus (IS) muscles of Italian Simmental young bulls (Bos taurus) were assessed. Samples from 10 animals were collected within 20 min of exsanguination (T0), after 48 h (T1) and 7 days (T2) post mortem. Calpain and caspase activity were evaluated based on the formation of αII spectrin cleavage products of 145 kDa (SBDP145) and 120 kDa (SBDP120), respectively. Caspase activity was also assessed by the presence of poly (adenosine diphosphate-ribose) polymerase-1 (PARP-1) cleavage product. At T0, LL showed higher levels of SBDP145 than IS (P < 0.01), while SBDP120 and PARP-1 degradation products were similar between muscles. At T1, no difference was found in the level of SBDP145 between muscles, while SBDP120 and PARP-1 cleavage products were not detected. At T2 neither αII spectrin nor PARP-1 cleavage products were found. LL and IS showed different proteolysis after slaughter that was influenced more by calpain than caspase activity, which was detectable only in the early post mortem period.

Influence of familiarity with goat meat on liking and preference for capretto and chevon

The research aimed at assessing liking and preference for capretto and chevon as a function of consumer familiarity with goat meat. Five meats were produced: traditional milk capretto (MC), heavy summer capretto (HSC), summering (SCh), fall (FCh) and late fall chevon (LFCh). HSC was the most tender meat, having less cooking losses than both MC and redder chevon types. The instrumental profile corresponded with the appearance and texture attributes perceived by panellists. With aging of kids, meat lost its milk aroma (MC) and sweet taste (HSC) and acquired an increasing intensity of goat flavour and livery notes, partially related to feeding regime and fatty acid profile. A niche market preferred chevon over capretto, while the cluster of consumers who were unfamiliar with chevon showed a decrease in pleasantness when tasting chevon, the familiar group reduced their ratings only for meat from the oldest kids.

Effect of supplement level on herbage intake and feeding behaviour of Italian Brown cows grazing on Alpine pasture

Riassunto Effetto del livello di integrazione sull’ingestione di erba e sul comportamento alimentare di vacche Brune al pascolo alpino. Per due anni consecutivi, 8 vacche di razza Bruna Italiana nel primo anno e 6 nel secondo, sono state mantenute su un pascolo alpino, per 5 settimane. Gli animali sono stati divisi in due gruppi omogenei e sottoposti a due diversi livelli di integrazione: 4,8 kg SO/d (livello alto) e 2,4 kg SO/d (livello basso) nel primo anno; 4,8 kg SO/d (livello alto) e 1,6 kg SO/d (livello basso) nel secondo anno. Scopo della prova era quello di verificare l’effetto del diverso livello di integrazione al pascolo sull’ingestione di erba, sulla produzione di latte e sul comportamento alimentare. L’aumento del livello di integrazione si è tradotto in un aumento dell’ingestione totale e della produzione di latte il primo anno e in una marcata diminuzione dell’ingestione di erba a fronte di consumi e produzione confrontabili il secondo. I tempi di pascolamento e di ruminazione sono risultati coerenti con i consumi di erba stimati.

Eating quality prediction of beef from Italian Simmental cattle based on experts' steak assessment

The experiment aimed at defining a grading scheme for Italian Simmental (IS) beef linked to objective measure of eating quality. Four experts developed a meat quality grid based on the assessment of the steak between the 8th and 9th ribs (reference steak). The grid was tested on the reference steak of 29 IS young-bulls. Rib-eye dimension, meat colour, marbling, meat firmness and fat cover highly contributed to overall quality. Two classes of IS beef quality were identified: standard and high. The results were associated with the sensory profile of Longissimus thoracis muscle from the reference steaks performed by a trained panel. The differences in quality highlighted by experts in raw steak accounted for most of the relevant information regarding the sensory properties of cooked beef. The accuracy of predictive model was 96.6%. The developed scheme is a helpful tool for valuing the eating quality of beef.

Body and meat characteristics of young bulls from Zebu Goudali of Cameroon and its crosses with the Italian Simmental

Abstract The aim of this trial was to compare the growth performance and meat yield and composition of SimGoud (Italian Simmental × Goudali, SG) crossbreed young bulls with those of pure Goudali (G) breed. Twenty-five G and 25 SG, from 20 to 41 months, reared together in Cameroon on native pasture were considered. Body size, growth and meat composition were compared. The SG crosses were more sized than the coetaneous pure G, having almost all body dimensions and mass index higher than G. Moreover, SG showed higher body weight at farm and ante-mortem than G, with about four times higher growth rate, but showed a marked loss of weight during transfer to slaughterhouse and lairage time. SG showed higher carcass weight and killing out percentage, in addition to a higher weight of rib steak and ribeye muscle at eighth–ninth rib section level than G. Despite the greater growth, differences between G and SG in beef proximate composition were not found. Genotype had a limited effect on fatty acids profile. However, G beef had greater CLA level, but lower MUFA content than SG. The study showed that G pure breed has much lower in vivo and slaughter performance than their crosses with the Italian Simmental breed, even if the meat composition was not different between the two genotypes. Conversely, despite similar pH of meat, G was more adaptable than SG to the severe transport condition and to the prolonged lairage time.

Comparison of longissimus thoracis physical quality traits and the expression of tenderness-related genes between Goudali zebu breed and Italian Simmental × Goudali crossbreed

Abstract The aim of this trial was to compare some meat physical quality traits and the expression of some tenderness-related genes between Goudali (G, Bos indicus) breed and Italian Simmental × Goudali (SimGoud, SG, Bos taurus x Bos indicus) crossbreed. Ten G and 12 SG bulls, aged 31 ± 0.49 months, bred in the same farm and conditions in Western Highland Plateau Savannah of Cameroon were considered. Physical quality traits of longissimus thoracis (LT) muscle such as water losses, colour parameters and rheological properties were determined together with ultimate pH (pHu). The mRNA early post-mortem abundance of calpain-1 (Capn1), calpain-2 (Capn2), calpastatin (Cast), caspase 3 (Casp3), caspase 9 (Casp9), αB-crystallin (Cryab), heat shock proteins 27 (Hsp27), 40 (Hsp40) and 70 (Hsp70) was detected by qPCR. The Capn1, Cast, Hsp27 and Hsp70, early post-mortem protein content was determined by ELISA. The meat of G bulls had greater values of lightness (p < .05) and cooking loss (p < .05) than SG. The expression of Hsp70 in G was greater at mRNA (p < .05) level than SG. None of the other variables considered was significantly different between G and SG breeds. Whereas crossbreeding with Italian Simmental breed changed the colour and ameliorated the water retention capacity of G meat, tenderness and the expression of tenderness-related genes, both at mRNA and at protein level, were not significantly different between the pure local breed and the crossbreed. In comparison with pure Goudali, crossbreeding Goudali with Italian Simmental breed has a limited impact on meat traits in tropical conditions.