Search

A portable electrical impedance spectroscopy device was developed to monitor the bioimpedance resistive component of bovine meat by injecting a sinusoidal current of 1 mA at 65 kHz. Both right and left longissimus dorsi muscles were trimmed from 4 slaughtered cows. The left muscle portions were frozen to −18 °C for 7 days while the right ones were meantime maintained at 5 °C. Mean value of impedance per length (Ω/cm) of frozen and thawed left samples was 31% lower than that of right non-frozen one (P = 0.0001). It was concluded that the device is reliable for monitoring the maturation of beef meat in situ with the possibility of revealing undeclared freeze-thaw cycles.

A portable electrical impedance spectroscopy device was developed to monitor the bioimpedance resistive component of bovine meat by injecting a sinusoidal current of 1 mA at 65 kHz. Both right and left longissimus dorsi muscles were trimmed from 4 slaughtered cows. The left muscle portions were frozen to -18 °C for 7 days while the right ones were meantime maintained at 5 °C. Mean value of impedance per length (O/cm) of frozen and thawed left samples was 31% lower than that of right non-frozen one (P = 0.0001). It was concluded that the device is reliable for monitoring the maturation of beef meat in situ with the possibility of revealing undeclared freeze-thaw cycles. [ABSTRACT FROM AUTHOR]

Summary: In the present study, a sample of 88 animals belonging to four local (Modicana, Sarda, Sardo‐Bruna and Sardo‐Modicana) and one cosmopolitan (Italian Brown Swiss) cattle breeds were genotyped with a medium density SNP beadchip and compared to investigate their genetic diversity and the existence of selection signatures. A total of 43 012 SNPs distributed across all 29 autosomal chromosomes were retained after data quality control. Basic population statistics, Wright fixation index and runs of homozygosity (ROH) analyses confirmed that the Italian Brown Swiss genome was shaped mainly by selection, as underlined by the low values of heterozygosity and minor allele frequency. As expected, local cattle exhibited a large within‐breed genetic heterogeneity. The FST comparison revealing the largest number of significant SNPs was Sardo‐Bruna vs. Sardo‐Modicana, whereas the smallest was observed for Italian Brown Swiss vs. Sardo‐Modicana. Modicana exhibited the largest number of detected ROHs, whereas the smallest was observed for Sardo‐Modicana. Signatures of selection were detected in genomic regions that harbor genes involved in milk production traits for Italian Brown Swiss and fitness traits for local breeds. According to the results of multi‐dimensional scaling and the admixture analysis the Sardo‐Bruna is more similar to the Sarda than to the Italian Brown Swiss breed. Moreover, the Sardo‐Modicana is genetically closer to the Modicana than to the Sarda breed. Results of the present work confirm the usefulness of single nucleotide polymorphisms in deciphering the genetic architecture of livestock breeds. [ABSTRACT FROM AUTHOR]

Infections by gastrointestinal nematodes negatively affect small ruminant health and at the same time cause substantial economic losses worldwide. Because resistance to conventional anthelmintic compounds is growing, target studies evaluating the effectiveness of alternative ingredients of botanical origin on gastrointestinal nematodes are needed. In this study, we evaluated the in vitro anthelmintic activity of Ruta chalepensis L. extracts on the third-stage larvae of sheep gastrointestinal nematodes. A methanol extract showed the highest anthelmintic activity, with an EC50 = 0.10 ± 0.06 mg/ml after 96 h, while the essential oil had an EC50 = 1.45 ± 1.22 mg/ml after 48 h. Moreover, three secondary metabolites of the essential oil, i.e. 2-decanone, 2-nonanone and 2-undecanone, showed EC50 values of 0.07 ± 0.06, 0.25 ± 0.29 and 0.88 ± 0.73 mg/ml at 24 h, respectively. The present study indicated that the R. chalepensis methanol extract, the essential oil and its metabolites 2-decanone, 2-nonanone and 2-undecanone showed promising anthelmintic activity on gastrointestinal nematodes. [ABSTRACT FROM AUTHOR]

Roasted piglet (Porcheddu) is one of the most appreciated traditional Sardinian dishes obtained from suckling animals slaughtered at 8-12 kg of body weight (BW). The traditional cooking method is timeconsuming; this dish is eaten only when there is enough time for its preparation (cooking time of about 2 h). The Porcheddu is appreciated by both local and foreign consumers and there is also an increasing interest, for this traditional dish, by extra regional consumers and markets. Actually, since the occurrence of African swine fever (ASF), the trade of pigs and pig meat products is not permitted from Sardinia. The Council Directive 2002/99/EC provided a derogation for states member to authorize the production, processing and distribution of products of animal origin when a Heat treatment at a minimum temperature of 80°C, which must be reached throughout the meat is applied. The overall framework of this study was to evaluate an innovative process to obtain a traditional dish the Porcheddu suitable to achieve extra-regional markets and meet the demand of modern consumers and to assess the effect of carcass weight on the processing yield of suckling piglets, thermally treated, to obtain a ready-to-eat roast dish. [ABSTRACT FROM AUTHOR]

The feedstuffs used in dairy animals must be able to give consumers confidence about the wholesomeness of milk with regard to aflatoxin contamination. The aim of this study was to determine the excretion patterns of aflatoxin M1 (AFM1) in the milk of dairy goats fed a single dose of pure aflatoxin B1 (AFB1), which can occasionally occur if feeds are infected by hot-spot growth of molds that produce aflatoxins. Five dairy goats in midlactation were administered 0.8 mg of AFB1 orally. Individual milk samples were collected for 84 h after AFB1 dosage. Aflatoxin M1 was found in milk in the highest concentration. In all goats, AFM1 was not detected in milk before AFB1 administration, but was detected in the first milking following AFB1 administration. The excretion pattern of AFM1 concentration in milk was very similar in all goats even if the values of the concentration differed between animals. The peak values for AFM1 concentration in milk was observed in milk collected during the milking at 3 and 6 h. After the peak, the AFM1 in milk disappeared with a trend that fitted well a monoexponential decreasing function, and the toxin was not detected after 84 h. Only about 0.17% of the amount of AFB1 administered was detected as AFM1 in milk, and about 50% of this was excreted in the first liter of milk yielded after AFB1 intake. Correct procedures to prevent growth of molds, and consequent AFB1 contamination, on the feedstuffs for lactating goats represent the key to providing consumers a guarantee that milk is not contaminated by AFM1. [ABSTRACT FROM AUTHOR]

During feed restriction, changes in metabolism occur and often result in the mobilization of energy from the adipose tissue. The objective of this work was to evaluate changes in the fatty acid (FA) profile of milk fat during short-term feed restriction in dairy ewes. Six ewes (3 at low-body condition score and 3 at high-BCS) were fed a complete pelleted diet (CPD) ad libitum (average intake of 2.5 kg/head per d) for 7 days, followed by 3 days of feed restriction of 50% of their previous intake (feed restriction group, FRG). Other 6 ewes (control, C group), divided into 3 low-BCS and 3 high-BCS sheep, were always fed CPD ad libitum (average intake of 2.5 kg/head per d). The CPD composition was (on a DM basis) 38.3% NDF, 16.0% CP and 4.5% EE (of which 2% of palm oil). The data of the 3-d treatment were analysed by a mixed model using BCS, group and their interaction as fixed factors and ewe as random factor. Milk fat content was higher in the FRG than in the C group (5.92 vs 4.67%), whereas fat yield was similar between groups. No effects of short-term feed restriction on C4-C14 fatty acids were observed. The FRG showed a lower content of C16:0 (26.46 vs 29.59%; P≤0.05) and cis9,cis12 C18:2 (4.42 vs 5.38%; P≤0.10) and a higher content of cis9 C18:1 (20.81 vs 17.56%; P≤0.05) than the C group. The content of total CLA (1.47 and 1.27 in the FRG and C group, respectively) was not influenced by the feed restriction treatment. The extent of variation in milk fatty acid profile in FRG group (expressed as percentage respect to C group) was influenced by BCS of ewes. The results suggest that feed restriction for a 3-d period is enough to cause changes in the FA profile of milk fat. The different responses observed in animals with high and low BCS was probably due to a different extent of body store mobilization when feed restriction occurred. [ABSTRACT FROM AUTHOR]

The effects of short-term feed restriction on milk yield and milk composition of Sarda dairy ewes were studied in a 17-d experiment. Twenty sheep were housed in individual pens and divided in two isoproductive groups. Ten ewes (feed restricted group, FRG) were fed a total mixed ration pelleted diet (TMR-PD) ad libitum (average intake of 2.5 kg/head per day) for 7 days (preliminary period), followed by 3 days of feed restriction of 50% of their previous intake (1.25 kg/head per day of TMR-PD) and 7 days of recovery. The other ten ewes (control, C group) were fed TMR-PD ad libitum during all the experimental period (average intake of 2.5 kg/head per day). There were no differences in milk yield between the two groups during the preliminary period (1485 and 1493 g/d for FRG and C group, respectively). Milk yield for the FRG decreased during the feed restriction period and averaged 72% of the values of the C group (1009 vs 1389 g/d, P≤0.001). Milk yield of the FRG was not completely restored during the 7-d recovery period, remaining lower than that of the C group (1278 vs 1451 g/d, P=0.12). Fat percentage tended to increase in FRG during the feed restriction period (5.87% vs 5.27%, P=0.08), and remained higher than that of the C group during recovery (6.04% vs 5.20%, P≤0.01). No effects of feed restriction on protein percentage (5.52% vs 5.53% for FRG and C group, respectively) were observed. SCC was lower in the FRG than in the C group during the preliminary period (Ln SSC 4.51 vs 4.71, P=0.06), increased by more than 4 fold during the feed restriction period (Ln SSC 5.34 vs 4.76, P=0.02) and remained higher during the recovery period (Ln SSC 5.4 vs 4.8, P=0.10). Short-term feed restriction caused a permanent drop in milk production and an increase in SCC on dairy ewes. [ABSTRACT FROM AUTHOR]

Grape seed is a by-product of the winery and distillery industry which could be used in animal nutrition. To test the hypothesis that dietary supplementation with this by-product can decrease the biohydrogenation (BH) of healthy fatty acids (FA), the present study evaluated the effects of grape seed supplementation, alone or combined with linseed, on ruminal BH processes in dairy sheep. In this 60-d trial, 24 lactating Sarda dairy ewes were assigned to four homogeneous groups and fed as follows: (1) control diet (CON), (2) a diet supplemented with 300 g/d per head of grape seed (GS), (3) a diet supplemented with 220 g/d per head of extruded linseed (LIN), (4) and a diet supplemented with a mix of both grape seed and linseed (300 and 220 g/d per head, respectively) (MIX). Ammonia, pH, volatile fatty acids (VFA) and FA composition were determined in rumen liquor at three sampling dates (20, 40 and 60 d). Rumen pH was not influenced by diet (P>0.05). The ammonia content was increased (P<0.05) in GS and MIX compared with LIN and CON. The molar proportions of acetate and propionate and their ratio were not affected by the diet (P>0.05), whereas the molar proportion of butyrate was the lowest in MIX. Rumenic acid (RA; CLA cis- 9, trans- 11) concentration increased in GS compared with CON (0.78 vs. 0.45 mg/100 mg FA; P<0.05), whereas the percentage of vaccenic acid (VA; C18:1 trans- 11) tended to increase (P<0.10) in GS compared with CON. The concentration of VA was higher in MIX than in CON (8.18 vs. 3.77 mg/100 mg FA; P<0.05), whereas RA did not differ between the same groups. The concentration of linoleic acid (LA; C18:2 n –6) decreased and stearic acid (SA; C18:0) increased in all supplemented groups, whereas linolenic acid (LNA; C18:3 n –3) decreased in the two groups receiving grape seed compared with CON and LIN. The concentration of total odd- and branched-chain fatty acids (OBCFA) decreased in all supplemented groups compared with CON (P<0.05), evidencing that grape seed and linseed supplementation influenced the ruminal BH processes. Grape seed was able to increase the accumulation of RA when supplemented alone, and of VA when combined with linseed; however, the rumen accumulation of SA in both groups supplemented with grape seed evidenced that this by-product was not effective in decreasing the BH of dietary polyunsaturated fatty acids (PUFA). [ABSTRACT FROM AUTHOR]