Induction of acrosome reaction by 4-Br-A23187 alters the glycoproteomic profile of boar spermatozoa.

Protein glycosylation is a post-translational modification involved in wide range of biological processes. In mammalian spermatozoa this modification has been identified in numerous proteins, and membrane glycoproteins are involved in the fertilization process. The objective of the present study was to identify changes in protein glycosylation after acrosome reaction (AR) induction using the 4-Br-A23187 ionophore. Our results showed that treatment with 10 µM of 4-Br-A23187 for 20 min significantly increased the percentage of live acrosome-reacted spermatozoa compared to the control (69.8 ± 0.8 vs. 6.4 ± 0.5; mean % ± SEM, respectively). Also, we observed an increase in 32 kDa tyrosine-phosphorylated protein (p32) and a decrease in serine/threonine phosphorylation of the protein kinase A substrates (phospho-PKA-substrates) after ionophore treatment. Furthermore, changes in glycosylated proteins following AR induction were analyzed using different HRP-conjugated lectins (GNA, DSA, and SNA), revealing changes in mannose and sialic acid residues. Proteomic analysis of isolated proteins using GNA lectin revealed that 50 proteins exhibited significantly different abundance (q-value < 0.01). Subsequent analysis using Uniprot database identified 39 downregulated and 11 upregulated proteins in the presence of 4-Br-A23187. Notably, six of these proteins were classified as transmembrane proteins, namely LRRC37A/B like protein 1 C-terminal domain-containing protein, Membrane metalloendopeptidase like 1, VWFA domain-containing protein, Syndecan, Membrane spanning 4-domains A14 and Serine protease 54. This study shows a novel protocol to induce acrosome reaction in boar spermatozoa and identifies new transmembrane proteins containing mannose residues. Further work is needed to elucidate the role of these proteins in sperm-oocyte fusion.

Processing of boar spermatozoa with phosphate-buffered saline at 4˚C induces an increase in 32 kDa tyrosine-phosphorylated protein (p32).

We aimed to investigate the impact of processing boar spermatozoa with phosphate-buffered saline (PBS) at 4 ˚C on acrosomal integrity and increase in 32 kDa tyrosine-phosphorylated protein (p32). Following cooled PBS washing, we observed a significant increase in p32 levels and in the proportion of dead spermatozoa with compromised acrosomal integrity compared to sperm washing using PBS at room temperature. Interestingly, this increase in p32 was effectively inhibited when cooled PBS was supplemented with 1 mM AEBSF, a serine protease inhibitor. Our findings suggest that the increase of p32 in response to cooled PBS washing in boar spermatozoa is associated with enhanced protease activity in dead spermatozoa.

Differences in Muscle Lipogenic Gene Expression, Carcass Traits and Fat Deposition among Three Iberian Pig Strains Finished in Two Different Feeding Systems.

The Iberian pig breed includes several well-differentiated strains. The present study evaluated carcass traits, fat deposition and muscle expression of important lipogenic genes (SCD, ME1, ACACA, FASN, EGR1, ACOX and ACLY) using 65 male pigs of 3 Iberian strains (20 Lampiño, 23 Torbiscal, and 22 Retinto) finished either in a conventional, concentrate-based system (CF) or in montanera (MF), a traditional free-range system with acorn feeding. Torbiscal had the highest ham, Longissimus thoracis and prime cuts yields, and the thinnest subcutaneous adipose tissue (SAT). Retinto had the highest monounsaturated fatty acids (MUFA) and percentage of intramuscular fat (IMF), while Lampiño had the greatest content of saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA), atherogenic (AI) and thrombogenic (TI) indexes in SAT. Conventionally finished pigs had the highest ham, L. thoracis and prime cuts yields, and SFA. Montanera-finished animals had the highest PUFA and MUFA contents, and the lowest AI, TI and n6/n3 ratio in SAT. In relation to gene expression, Retinto had the greatest SCD, FASN and ACLY levels. Most studied genes were overexpressed in CF pigs. In conclusion, MF pigs had healthier fat than CF pigs, and Retinto had the healthiest fat and the greatest lipogenic trend in muscle, supported by IMF and lipogenic gene expression.

Effects of breed-production system on collagen, textural, and sensory traits of 10 European beef cattle breeds.

In the current study the collagen, texture, and sensory characteristics of meat from 712 yearling males of 10 local Spanish and French beef breeds raised in their typical production systems were described. The breed-production system affected collagen and texture variables but affected sensory variables only slightly. There was a large amount of intra breed-production system variation for all the variables. French breeds had lower values for collagen solubility (~12%) than Spanish breeds (~40%). Stress (WB) varied from 36 N/cm2 in Casina to 44 N/cm2 in Salers, whereas compression stress at 80% ranged from 35 N/cm2 in Asturiana de los Valles to 40 N/cm2 in Salers. Oven cooking resulted in higher cooking losses (24%) than cooking on a grill (12%). Cooking losses increased as the grill temperature increased. Numerous significant correlations were found among variables. Carcass weight is associated with all the collagen and texture variables. Correlation coefficients among texture and collagen variables were statistically significant and these correlation coefficients were in general higher for solubility percentage than for total collagen content, highlighting the importance of the solubility of collagen rather than total collagen in determining meat textural properties. PRACTICAL APPLICATIONS: To differentiate a product in the market, it is necessary to define its characteristics. Differentiation allows increasing the added value of products and, therefore, income of the farmers. In addition, it guarantees to the consumers that the product they purchase has the intrinsic and extrinsic quality features that they seek. For consumers, beef texture is one of the most important quality attributes sought, therefore, studying factors that can affect beef texture is a major interest for the industry.

Changes in adipose cells of Longissimus dorsi muscle in Iberian pigs raised under extensive conditions.

Twenty-four Iberian castrated male pigs were used to characterize and evaluate the effect of the duration of "Montanera" in the adipocytes size and its relation with the backfat thickness and intramuscular fat. The animals were fed under extensive conditions during 30, 60 and 90 days in the "Dehesa" before slaughtered. Carcass weight, percentage of intramuscular fat, thickness of backfat and its three layers and adipocytes size of the intramuscular fat were obtained. The group which expended 90 days on fattening obtained the highest adipocytes, with an area higher by a 50% than those that only expended 30 days. The differences in diameter and perimeter adipocyte were not as marked as area. A significant positive correlation between the diameter, area and perimeter of adipocyte with the backfat thickness were found. The fat cells in Iberian pig hypertrophy during the "montanera stage", being this increase significant from month to month in this period of fattening. Also, this adipocyte increase is correlated with the animal weight. The correlation between adipocyte size and inner layer of backfat shows that the inner layer obtained in live pig by ultrasound techniques could be a good marker of fat infiltration in pigs fattening in "montanera" system.

Changes in adipose cells of Longissimus dorsi muscle in Iberian pigs raised under extensive conditions

ABSTRACT Twenty-four Iberian castrated male pigs were used to characterize and evaluate the effect of the duration of "Montanera" in the adipocytes size and its relation with the backfat thickness and intramuscular fat. The animals were fed under extensive conditions during 30, 60 and 90 days in the "Dehesa" before slaughtered. Carcass weight, percentage of intramuscular fat, thickness of backfat and its three layers and adipocytes size of the intramuscular fat were obtained. The group which expended 90 days on fattening obtained the highest adipocytes, with an area higher by a 50% than those that only expended 30 days. The differences in diameter and perimeter adipocyte were not as marked as area. A significant positive correlation between the diameter, area and perimeter of adipocyte with the backfat thickness were found. The fat cells in Iberian pig hypertrophy during the "montanera stage", being this increase significant from month to month in this period of fattening. Also, this adipocyte increase is correlated with the animal weight. The correlation between adipocyte size and inner layer of backfat shows that the inner layer obtained in live pig by ultrasound techniques could be a good marker of fat infiltration in pigs fattening in "montanera" system.

[Surveillance and control measures of avian influenza in birds. Implications for public health]. / Medidas de vigilancia y contención de la influenza aviar en aves. Implicaciones para la salud pública.

Avian influenza is an infectious disease that mainly affects birds, caused by influenza A type viruses, in most cases of low pathogenecity. Rapid mutations of these viruses to highly pathogenic forms represent a serious risk for animal and public health. Since 2003, an outbreak of highly pathogenic avian influenza in birds is taking place with transmission and resulting illness in humans and which is believed to be able to start a human influenza pandemic. To face these outbreaks, a joint effort between the animal and public health sector is needed to identify areas affected by animal disease and to intensify surveillance of human cases in them. Control measures in animals must be compatible with risk reduction of human exposure. The aim of this article is to review the general control measures developed against avian influenza in birds, highlighting coordination and communication aspects between Animal Health and Public Health, taking into account that legislation is constantly being updated as the dynamic of the disease changes.