REASONS FOR DEFERRAL IN DEFERRED VOLUNTARY BLOOD DONORS IN EASTERN CROATIA

When choosing a voluntary blood donor (VBD), it is important to ensure the donor health, and at the same time to produce a quality and safe blood product. The donor selection process leads to donor rejection related to their current health condition. The aim of this study was to determine gender differences in VBDs, to examine the reasons for their rejection, and to determine the share of permanently and temporarily deferred VBD, especially due to low hemoglobin levels. The research was conducted in eastern Croatia in the 2014 to 2018 period. The study included 144,041 blood donations from a total of 80,418 VBDs, of which 83.3% of donations were from male VBDs and 16.7% from female VBDs. There were 11.46% of temporarily deferred and permanently rejected donors. Out of all temporarily deferred donors and possible reasons for deferral, the largest share of deferrals referred to a reduced hemoglobin level, which accounted for 54% in female VBD and 46% in male VBD. Female VBDs made up to one-third of total VBDs and account for one-sixth of total blood donations. Low hemoglobin was the most common reason for VBD deferral. Gender and age are related to blood hemoglobin levels in rejected and accepted donors. Female VBDs represent a potential reservoir for increasing the total number of VBDs.

Risk Evaluation for Coating Thickness Conformity Assessment

This paper presents the conformity assessment process of the epoxy coating thickness applied on water pipes made of gray cast iron with the specifications given for this kind of coating appliance. An epoxy coating was applied to prevent a special form of corrosion called the graphitization of cast iron. In order for the pipe to withstand its designed service life, it is necessary to ensure the required thickness of the applied coating. In accordance with the EN 877 norm, the thickness of the epoxy coating on the pipes for the projected corrosiveness of the environment C4 and the durability of 20 years is at least 70 μm and this indicates the required accuracy of the product. To achieve the desired product quality, statistical control of the coating application process was carried out and the impact of uncertainty associated with the measurement result was analyzed. Considering the quality of the coating application process and the quality of the measuring system, and to ensure the quality of products and to reduce consumer risk, the optimal thickness of the coating was determined.

Effects of dietary clinoptilolite on reproductive performance, serum progesterone and insulin-like growth factor-1 concentrations in dairy cows during pregnancy and lactation

The objective of this study was to evaluate the effects of dietary zeolite clinoptilolite on re- productive performance, serum progesterone and insulin-like growth factor 1 (IGF-1) concentra- tions in 78 Holstein Friesian (HF) cows during pregnancy and lactation. The cows were divided into two groups comprising 40 (control group; CON) and 38 (CPL group) cows. To assess repro- ductive performance of HF cows the following variables were registered: the interval from calv- ing to first insemination (days open to first service, DFS), the interval from calving to pregnancy (days open to pregnancy, DOP), and the number of services per pregnancy (NSP). The average values of progesterone (5.64±0.59 ng/mL vs. 5.16±0.64 ng/mL) were not statistically different (p⟨0.05) and IGF-1 levels (400.17±17.72 ng/mL vs. 348.36±20.39 ng/mL) were higher in the CON than in the CPL group which received 50 g of clinoptilolite twice a day. However, in the CPL group ovarian cyclity resumed on days 40 and 60 postpartum. In addition, DFS (p⟨0.05) and DOP (p>0.05) were shorter in the CPL than in the CON group (115.1±19.9 and 137.5±36.3 days vs. 124.2±17.3 and 143.8±33.5 days, respectively). During 305 days of lactation, milk production was higher in the CPL vs. CON (8325.5±628.8 kg vs. 8050±586.8 kg). The NSP was lower in the CPL than in CON group (1.91 vs. 2.14). The dietary clinoptilolite supplement had a positive in- fluence on milk yield, exhibited modulating effects on endocrine status of dairy cows, and im- proved reproductive performance, with the decreased NSP, and fewer DFS and DOP.

Reproductive immunology in viviparous mammals: evolutionary paradox of interactions among immune mechanisms and autologous or allogeneic gametes and semiallogeneic foetuses

Literally, reproductive immunology was born in bovine on-farm reproduction where seminal experiments intended for developing methods for embryo transfer in cattle were performed. Actually, these experiments led to two of major concepts and fundamental principles of reproductive immunology using the bovine species as a model for biomedical research, namely the concept of acquired immunological tolerance and the paradox of the semiallogeneic bovine foetus whereby such organism can develop within an immunologically competent host. Peter Medawar, a scientist who together with Frank Macfarlande Burnet shared the 1960 Nobel Prize in physiology or medicine for discovery of acquired immunological tolerance, while studying dizygotic cattle twins, thereby giving birth to reproductive immunology. Also, these findings significantly influenced development of organ transplants and showed that using farm animals as models for studying transplantation immunology had general relevance for mammalian biology and health including those of humans. However, the interest for further research of the fascinating maternal immune influences on pregnancy and perinatal outcomes and of the prevention and treatment of immunologically mediated reproductive disorders in viviparous mammals of veterinary relevance by veterinary immunologists and reproductive clinicians have been very scarce regarding the application of nonspecific immunomodulatory agents for prevention and treatment of subfertility and infertility in pigs and cattle, but still broadening knowledge in this area and hold great potential for improving such therapy in the future. The aim of the current overview is to provide up-to-date information and explaining/translating relevant immunology phenomena into veterinary practice for specialists and scientists/clinicians in reproduction of animals.

The influence of exogenous melatonin on antioxidative status in seminal plasma and spermatozoa in French Alpine bucks during the nonbreeding season

Research data regarding exogenous melatonin effects on buck semen antioxidative status during the breeding and nonbreeding seasons are scarce or missing. The aim of this study was to investigate the effect of melatonin implants on the activity and ratios of antioxidative enzymes and on malondialdehyde concentrations in the seminal plasma and spermatozoa of French Alpine bucks during the 3 mo of the nonbreeding season. Two groups of randomly assigned bucks were either treated with melatonin (n = 6) or served as controls (n = 6). Semen samples were collected weekly, seminal plasma was separated from spermatozoa, and activities of glutathione peroxidase (GSH-Px), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT), and the concentration of malondialdehyde were determined. The melatonin-treated bucks had significantly higher CAT/SOD and GSH-Px/SOD ratios, but a significantly lower GR/GSH-Px ratio in seminal plasma and spermatozoa during the different periods of the nonbreeding season. In conclusion, exogenous melatonin influenced the activities of all ratios and some single antioxidative enzymes tested in bucks' seminal plasma and spermatozoa. Here we provide the first evidence derived from an intervention, that is, melatonin treatment, which affects antioxidative enzymes ratios in the semen of bucks, and could thus be recommended as an indicator of oxidative stress severity and antioxidative status of semen.

HLA-A, -B, -C, -DRB1, -DQA1, and -DQB1 allele and haplotype frequencies defined by next generation sequencing in a population of East Croatia blood donors

Next-generation sequencing (NGS) is increasingly used in transplantation settings, but also as a method of choice for in-depth analysis of population-specific HLA genetic architecture and its linkage to various diseases. With respect to complex ethnic admixture characteristic for East Croatian population, we aimed to investigate class-I (HLA-A, -B, -C) and class-II (HLA-DRB1, -DQA1, -DQB1) HLA diversity at the highest, 4-field resolution level in 120 healthy, unrelated, blood donor volunteers. Genomic DNA was extracted and HLA genotypes of class I and DQA1 genes were defined in full-length, -DQB1 from intron 1 to 3′ UTR, and -DRB1 from intron 1 to intron 4 (Illumina MiSeq platform, Omixon Twin algorithms, IMGT/HLA release 3.30.0_5). Linkage disequilibrium statistics, Hardy-Weinberg departures, and haplotype frequencies were inferred by exact tests and iterative Expectation-Maximization algorithm using PyPop 0.7.0 and Arlequin v3.5.2.2 software. Our data provide first description of 4-field allele and haplotype frequencies in Croatian population, revealing 192 class-I and class-II alleles and extended haplotypic combinations not apparent from the existing 2-field HLA reports from Croatia. This established reference database complements current knowledge of HLA diversity and should prove useful in future population studies, transplantation settings, and disease-associated HLA screening.

THE IMPACT OF POSITIVE ANTI-HBC MARKER ON PERMANENT DEFERRAL OF VOLUNTARY BLOOD DONORS IN EASTERN CROATIA AND ESTIMATION OF OCCULT HEPATITIS B VIRUS INFECTION RATE

Recently an increase has been reported in the number of HBV transmissions from anti-HBc positive blood donors that were repeatedly negative in HBsAg and nucleic acid testing using the most sensitive tests available. The aim of the study was to show the effect of anti-HBc antibody testing performed in 2006 on permanent deferral of voluntary blood donors (VBDs), and to estimate occult hepatitis B infection (OBI) rate in this population after the introduction of mandatory molecular testing in the 2013-2016 period. More than 30,000 blood donations collected during the 2005-2007 period and more than 14,000 VBDs having donated blood during the 2013-2016 period after the introduction of molecular testing from eastern Croatia were included in the study. Serologic testing was performed with HBsAg assay throughout the study period, and anti-HBc assay was only performed in 2006. As part of the confirmatory algorithm testing, all HBsAg positive and unclear results were tested with molecular tests. Anti-HBc prevalence among VBDs in 2006 was 1.5%, with a rate of 1:197, whereas HBsAg prevalence was stable from 2005 to 2007 (0.04%, 0.1% and 0.1%, respectively). The calculated OBI rate from 2013 to 2016 was 1:30,250. Ten of 161 (12.4%) VBDs had serologic anti-HBc-only pattern. Anti-HBc testing in 2006 resulted in statistically more deferrals of VBDs compared to 2005 and 2007, and to the rest of Republic of Croatia. The strategy of universal anti-HBc testing of VBDs in addition to the existing HBsAg and molecular screening could be an additional measure to prevent HBV transmission by blood and blood components.

Monitoring of libido and semen quality parameters in melatonin-treated French alpine bucks during the non-breeding season

The aim of this study was to investigate the effects of exogenous melatonin on libido and semen quality parameters in bucks during the non-breeding season. Twelve bucks of the French alpine breed from 1.5 to 4 years of age were assigned into melatonin (MG) and control (CG) groups, with 6 bucks in each group. The experimental period was 3 months (March-May), divided into six periods of 15 days each. The bucks in the MG group received four melatonin implants at the end of March. Two semen samples were taken from the bucks by artificial vagina once per week and their libido estimated. Volume and spermatozoa concentration, their mass motility and motility, proportion of live and total abnormal and forms with abnormal head and tail were determined in the obtained ejaculate samples. The total number of spermatozoa and functional spermatozoa fraction in the ejaculate was also calculated. The MG bucks had significantly higher mass motility and motility of spermatozoa in the first half of April, and a higher proportion of live spermatozoa in the first and second half of April (p < .05). Differences in libido intensity were not significant. The results indicated that the application of melatonin significantly improved the qualitative parameters of semen in bucks, as seen in increased mass motility, motility of spermatozoa and proportion of live spermatozoa shortly following melatonin insertion. Therefore, the results of the current study are novel regarding the use of melatonin treatment during the non-breeding season to improve the qualitative parameters of ejaculates in bucks.

The onset of puberty in Cameroon Dwarf goats kept as pets in northwestern Croatia

The aim of this study was to determine onset of puberty in Cameroon Dwarf goats (CDGs) kept as pets in northwestern Croatia by determining progesterone (PGS) and insulin-like growth factor-I (IGF-I) levels in the blood by RIA methods. The first cyclic ovarian activity was estimated according to hormone profiles as determined in CDG in a moderate climate environment. Sixteen female CDG kids were kept in stables with access to pasture which provided space for exercise. The goat kids born in winter (December-January-February), spring (March-April-May), summer (June-July-August) and autumn (September-October-November) were assigned into four groups according to the season of the year of birth (n = 4 in each group). At 75 days of age at the initiation of the study, they weighed between 3.2 and 5.1 kg (4.24 ± 0.53 kg). The onset of ovulatory activity was determined by PGS and IGF-I serum concentrations every 10 days starting from 75 days to 155 days of age. The onset of puberty in CDG kids occurred on average at 141.15 ± 2.66 days of age, but varied depending on the season of birth. All CDG kids born during summer were in heat by 155 days of age. In the other groups (kids born in autumn, winter or spring), one goat in each group was not in heat. Changes in blood serum PGS and IGF-I concentrations during prepubertal and pubertal periods could aid in the evaluation of reproductive status and determination of the onset of puberty in CDG during all seasons of the year in a moderate climate region.

Effect of age and environmental factors on semen quality, glutathione peroxidase activity and oxidative parameters in Simmental bulls

Taking into account that semen quality depends on animal age and climate conditions and that oxidative stress has been reported to be a common cause of infertility, the objective of this study was to monitor indicators of oxidative stress and antioxidant protection during four seasonal periods in service bulls of various age to get better insight into the significance of these factors upon evaluating service bull semen. The research was conducted over a year on 19 Simmental service bulls. Animals were divided into two groups according to age; Group I consisted of younger bulls aged two to four yrs (n=9), and Group II was comprised of older bulls aged five to ten yrs (n=10). Semen samples were obtained once in the middle of every seasonal period and blood samples for biochemical analysis were collected by jugular venipuncture immediately after ejaculate collection. The activity of total glutathione peroxidase (T-GSH-Px), selenium-dependent glutathione peroxidase (Se-GSH-Px) and selenium-independent glutathione peroxidase (non-Se-GSH-Px), together with the intensity of lipid peroxidation (thiobarbituric acid reactive substances; TBARS) and oxidative protein damage (protein carbonyl content (PCC)) were measured in seminal plasma. In samples of spermatozoa and blood serum, the activity of Se-GSH-Px and TBARS and PCC concentrations were determined. Older service bulls had significantly higher ejaculate volume in summer in comparison with younger bulls, whereas the number of spermatozoa and progressive motility percentage did not significantly vary with age. Younger animals had lower progressive motility percentage during summer than in spring, with more intensive oxidative processes observed in seminal plasma (TBARS) and spermatozoa (TBARS and PCC). Based on the results presented here, it can be concluded that younger bulls are more sensitive to elevated ambient temperatures during the summer, when intensified prooxidative processes in semen plasma and spermatozoa eventually led to decreased sperm progressive motility with consequential semen quality deterioration.