Understanding the Pathogenesis of Red Mark Syndrome in Rainbow Trout (Oncorhynchus mykiss) through an Integrated Morphological and Molecular Approach.

Red mark syndrome (RMS) is a widespread skin disorder of rainbow trout in freshwater aquaculture, believed to be caused by a Midichloria-like organism (MLO). Here, we aimed to study the pathologic mechanisms at the origin of RMS by analyzing field samples from a recent outbreak through gene expression, MLO PCR, quantitative PCR, and a histopathological scoring system proposed for RMS lesions. Statistical analyses included a One-Way Analysis of Variance (ANOVA) with a Dunnett's multiple comparisons test to assess differences among gene expression groups and a nonparametric Spearman correlation between various categories of skin lesions and PCR results. In short, the results confirmed the presence of a high quantity of 16S gene copy numbers of Midichloria-like organisms in diseased skin tissues. However, the number of Midichloria-like organisms detected was not correlated to the degree of severity of skin disease. Midichloria-like organism DNA was found in the spleen and head kidney. The spleen showed pathologic changes mainly of hyperplastic type, reflecting its direct involvement during infection. The most severe skin lesions were characterized by a high level of inflammatory cytokines sustaining and modulating the severe inflammatory process. IL-1 ß, IL-6, IL-10, MHC-II, and TCR were upregulated in severe skin lesions, while IL-10 was highly expressed in moderate to severe ones. In the moderate form, the response was driven to produce immunoglobulins, which appeared crucial in controlling the skin disease's severity. Altogether our results illustrated a complex immune interaction between the host and Midichloria-like organism.

Hempseed By-Product in Diets of Italian Simmental Cull Dairy Cows and Its Effects on Animal Performance and Meat Quality.

Cull dairy cows are important contributors to total beef production in the USA and in Europe. Hempseed cake is a by-product of oil production and it is rich in unsaturated fatty acids (FA). This study aimed to investigate the effect of adding hempseed cake to the diet of Italian Simmental (IS) cull dairy cows on performances and meat quality. Twenty-six cull dairy cows were divided into three dietary groups: hay-based, corn silage-based and pasture-based diets. Within each group, the animals were equally divided into two treatments according to the protein source of the concentrate: hempseed cake (HEMP) or soybeans meal (SB). The trial lasted four months. HEMP showed similar in vivo performance and carcass characteristics, such as average daily gain (p > 0.05) and dressing percentage (p > 0.05), compared with SB. Meat characteristics, such as ether extract content and Warner−Bratzler shear force, were also similar between experimental groups (p > 0.05). Considering FA composition, HEMP showed similar saturated FA and polyunsaturated FA content (p > 0.05) but lower desirable fatty acids (p < 0.05) content and a tendentially lower hypocholesterolemic/hypercholesterolemic ratio (p < 0.10) than SFA. Hempseed cake can substitute soybean in the diet of cull dairy cows without effects on performance or meat quality.

Gas Chromatography Combustion Isotope Ratio Mass Spectrometry to Detect Differences in Four Compartments of Simmental Cows Fed on C3 and C4 Diets.

Fatty acids (FAs) metabolism in animals represents an important field of study since they influence the quality and the properties of the meat. The aim of this study is to assess the possibility to discriminate the diets of cows in different animal compartments and to study the fate of dietary FAs in the bovine organism, using carbon isotopic ratios. Five FAs, both essential (linoleic and linolenic) and non-essential (palmitic, stearic, and oleic) in four compartments (feed, rumen, liver, meat) of animals fed two different diets (based on either C3 or C4 plants) were considered. For all compartments, the carbon isotopic ratio (δ13C) of all FAs (with few exceptions) resulted significantly lower in cows fed on C3 than C4 plants, figuring as a powerful tool to discriminate between different diets. Moreover, chemical reactions taking place in each animal compartment result in fraction processes affecting the δ13C values. The δ13CFAs tendentially increase from feed to meat in group C3. On the other hand, the δ13CFAs generally increase from rumen to liver in group C4, while δ13CFAs of rumen and meat are mostly not statistically different. Different trends in the δ13CFAs of the two groups suggested different FAs fates depending on the diet.

Fatty acids stable carbon isotope fractionation in the bovine organism. A compound-specific isotope analysis through gas chromatography combustion isotope ratio mass spectrometry.

The contribution of dietary fatty acids to the quality of the meat and their path through the bovine organism is currently the subject of a lot of research. Stable isotope ratio analysis represents a powerful tool for this aim, one that has not been studied in depth yet. In this work, for the first time, the carbon isotopic ratios of six fatty acids (myristic 14:0, palmitic 16:0, stearic 18:0, oleic 18:1n-9, linoleic 18:2n-6 and linolenic 18:3n-3 acids) in different matrixes (diet, rumen, duodenal content, liver and loin) were analysed through gas chromatography combustion isotope ratio mass spectrometry. Moreover, the quantification of the single fatty acids was carried out, providing important information supporting the carbon isotopic ratio results. The variation in the concentration of the fatty acids in the different matrices depends on the chemical modifications they undergo in the sequential steps of the metabolic path. GC-C-IRMS turned out to be a powerful tool to investigate the fate of dietary fatty acids, providing information about the processes they undergo inside the bovine organism.

Effect of Heat Stress on Dairy Cow Performance and on Expression of Protein Metabolism Genes in Mammary Cells.

The aim of this study was to assess the effect of heat stress on dairy cow performance and on the expression of selected genes involved in milk protein metabolism. Eight Italian Holstein Friesian cows were kept under thermoneutral conditions (temperature-humidity index (THI) < 72, CON) for 8 days and under mild heat stress conditions (72 < THI < 78, HS) for an additional 8 days. The rectal temperature, feed intake, and milk yield were recorded during the last 3 days of the CON and HS periods. During the same time period, milk samples were collected to assess the composition and expression of selected genes involved in milk protein metabolism. Gene expression analyses were performed on somatic cells from milk, which are representative of mammary tissue. In terms of dairy cow performance, HS resulted in lower milk and protein yields and feed intake but higher rectal temperature than for CON (p < 0.05). Under HS, there were greater abundances of HSPA1A (p < 0.05) and BCL2 (p < 0.05), compared to CON, but similar levels of CSN2 (p > 0.05), CSN3 (p > 0.05), HSPA8 (p > 0.05), and STAT5B (p > 0.05) mRNA. Mild heat stress reduced the performance of dairy cows without affecting the expression of genes coding for caseins.

Metagenomic profiles of different types of Italian high-moisture Mozzarella cheese.

The microbiota of different types of Italian high-moisture Mozzarella cheese produced using cow or buffalo milk, acidified with natural or selected cultures, and sampled at the dairy or at the mass market, was evaluated using a Next Generation Sequencing approach, in order to identify possible drivers of the bacterial diversity. Cow Mozzarella and buffalo Mozzarella acidified with commercial cultures were dominated by Streptococcus thermophilus, while buffalo samples acidified with natural whey cultures showed similar prevalence of L. delbrueckii subsp. bulgaricus, L. helveticus and S. thermophilus. Moreover, several species of non-starter lactic acid bacteria were frequently detected. The diversity in cow Mozzarella microbiota was much higher than that of water buffalo samples. Cluster analysis clearly separated cow's cheeses from buffalo's ones, the former having a higher prevalence of psychrophilic taxa, and the latter of Lactobacillus and Streptococcus. A higher prevalence of psychrophilic species and potential spoilers was observed in samples collected at the mass retail, suggesting that longer exposures to cooling temperatures and longer production-to-consumption times could significantly affect microbiota diversity. Our results could help in detecting some kind of thermal abuse during the production or storage of mozzarella cheese.

Effect of dietary nitrogen level and source on mRNA expression of urea transporters in the rumen epithelium of fattening bulls.

This paper aims to study the effect of the dietary treatments on mRNA expression of urea transporter B (UT-B) and some aquaporins (AQP) in rumen epithelium of Italian Simmental young bulls. Eighty animals allocated to 16 pens were fed from about 500 to 650 kg body weight with four experimental diets, which resulted from the combination of two crude protein levels (125 and 110 g/kg dry matter, diets M and L, respectively) and two nitrogen sources (soybean meal (SBM) or SBM partly replaced by an isonitrogenous mixture of corn and urea; diets -U and +U, respectively). At slaughtering samples of blood and rumen epithelium were collected from six bulls for each diet. Blood samples were analysed for haematological parameters and quantitative PCR was carried out on the mRNA extracted from the rumen epithelium samples. The bulls fed diets M had lower plasma concentrations of aspartate aminotransferase than those receiving diets L (78.9 vs. 88.3 U/l, p = 0.04). Plasma urea was higher (p = 0.03) for diets M and lower for diets +U (2.0 vs. 2.5 and 1.73 vs. 2.00 mmol/l, respectively, in M and L diets, p = 0.04). The effect of dietary treatments on rumen UT expression were limited to AQP3, which was down regulated (p = 0.01) in diets +U. Finally, a high positive correlation (R2 = 0.871) between the expressions of AQP7 and AQP10 was found. In conclusion, the AQP3 appears very responsive to dietary treatments and therefore it is a candidate to be further studied in rumen metabolism experiments. The close relationship between mRNA expression of AQP7 and AQP10 indicates a similar function of these two proteins.

Organic meat quality of dual purpose young bulls supplemented with pea (Pisum sativum L.) or soybean.

BACKGROUND: One of the main constraints established by organic legislation that limits the development of the rearing of young bulls is the ban on the use of genetically modified organisms (GMO). Most of the worldwide cultivated soybean is GMO, therefore the use of alternative protein sources should be evaluated. In this study, the effect of dietary substitution of soybean with pea (Pisum sativum L.) on carcass characteristics and meat quality of dual purpose young bulls reared following the organic method was investigated. RESULTS: Twenty-four young bulls of Rendena breed were randomly assigned to two diet treatments differing in protein supplement (soybean (SB) or field pea (FP)). Carcass characteristics and meat chemical composition, colour, cooking loss and Warner-Bratzler shear force did not differ between groups. Regarding meat fatty acid composition, SB showed higher concentrations of C18:0 and C18:1 t and lower C16:1n-9c, C14:0, C17:1n-9c and C18:1n-9c than FP. In descriptive sensory analysis, trained judges were not able to differentiate meats from SB and FP, which also had similar overall liking expressed by consumers. CONCLUSION: The results of this study indicate that FP can replace SB in the diet of dual purpose young bulls with only a minor influence on fatty acid composition and no effect on carcass characteristics and meat quality. © 2017 Society of Chemical Industry.

Prevalence of bovine dermatophilosis and disease-associated alleles in zebu Goudali cattle and their Italian Simmental crosses ranching in the western highland plateau savannah of Cameroon.

Abundance of native pastures makes Cameroon's western highland savannah (WHS) a hotspot for low-input beef-type cattle. Dumbo Ranch is central to cattle seed stock multiplication in WHS and holds that Dermatophilus congolensis infection undermines production. The bovine BoLA-DRB3 has been variously demonstrated as the principal gene of the major histocompatibility locus associated with immunity and resistance to dermatophilosis in cattle. We studied the profile of dermatophilosis prevalence in zebu Goudali (G) and its Simmental composite, SimGoud (SG), at Dumbo Ranch and determined the distribution of a dermatophilosis-associated susceptibility allele of the BoLA-DRB3 gene by allele-specific polymerase chain reaction (PCR). We recorded a 42 % prevalence of dermatophilosis in the studied cohort (337 animals). Dermatophilosis was more common in older cattle than in cattle ≤36 months (p ≤ 0.05). G was more affected compared to SG, because of the prevalence of the disease in the oldest animals and the age distribution of the experimental subjects. No susceptible homozygote was observed. About 85 and 15 % of the cohort carried the homozygous resistant and heterozygous condition, respectively. This genotype distribution was not affected by cattle type. The study confirms the presence of dermatophilosis among G and SG cattle in WHS. However, there was no correlation between the presence of the disease-associated susceptible allele considered and clinical manifestation. Screening for this dermatophilosis resistance-associated allele of BoLA-DRB3 gene appeared not useful for selection of G and SG in WHS.

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.

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.

Early post mortem expression of genes related to tenderization in two Italian Simmental young bulls' skeletal muscles differing in contractile type.

The early post mortem expression of eight genes potentially involved in meat ageing process and the tenderness of two Italian Simmental young bulls' (Bos taurus) skeletal muscles differing in their contractile type were evaluated. Samples of Longissimus lumborum (LL) and Infraspinatus (IS) muscles were collected from 17 bulls. The messenger RNA (mRNA) abundances of calpain-1, calpain-2, calpastatin, caspase 3, caspase 9, heat shock protein 27 (Hsp27), Hsp40 and Hsp70 were detected by quantitative PCR. The myosin heavy chain-slow and -fast isoform content, the pH48h and the lipid content of the muscles were in line with the contractile and metabolic type. In comparison with the fast LL, the slow IS showed a lower calpain-1/calpastatin mRNA content ratio after slaughtering and a higher Warner-Bratzler Initial Yield value after 7 days of ageing. Hsp27 and Hsp70 mRNA abundances were significantly lower in LL than IS, highlighting their potential role in the ageing process of bovine muscles.

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.

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.