Genetic and environmental analysis of female calf survival in the Israel Holstein cattle population

The objectives were to estimate the effects of various environmental factors on female calf survival of Israeli Holsteins, to estimate the economic value of calf survival under Israeli conditions, to estimate the genetic and environmental variance components for calf and cow survival using the individual animal model, to perform GWAS analyses of survival to first calving and herd life after first calving, to estimate the genetic and environmental trends for calf survival since 1985, to estimate genetic correlations of calf survival with the traits included in the current Israeli breeding index, and to estimate the consequences of inclusion of calf survival in the national selection index. Mean calf survival rate of Israeli Holsteins from 2001 through 2008 was 0.85, and the mean economic value of survival to first calving was $526. Birth month, gestation length, dystocia, and twin birth significantly affected calf survival rate. Dystocia and twin birth each reduced survival rate by 0.034. Survival rate was highest for calves born in October and lowest for calves born in February. The difference between these months was 3.4%. Maximum survival was at a gestation length of 276 d, the mean gestation length for this population. Survival rate was reduced to 0.76 for calves born after a gestation length of 260 d. The individual animal model was applied for all the genetic analyses. Heritability for calf survival to first calving, as estimated by REML, was 0.009, whereas heritability of herd life from first calving was 0.15. The complete data set for genetic analysis of survival to first calving included 1,235,815 calves born between 1985 and 2017. Annual genetic and phenotypic trends for calf survival were 0.019 and 0.015%, respectively. Correlations of transmitting abilities of 226 sires born since 2010 for calf survival with the traits included in the Israeli breeding index were significant only for the maternal effects of dystocia and stillbirth. The GWAS analysis was based on the transmitting abilities of 1,493 bulls with genotypes and reliabilities >0.5 for calf survival and cow herd life. There were 7 single nucleotide polymorphisms with coefficients of determination >0.03 for calf survival and 12 single nucleotide polymorphisms with coefficients of determination >0.05 for cow survival. There was no overlap between the genome-wide significant markers for the GWAS analyses of calf survival and cow herd life. This corresponds to the conclusion from the REML results and the low correlations between the sire evaluations that the genetic control of the 2 traits are not similar. Inclusion of calf survival in the Israeli breeding would result in a 0.5% increase in calf survival over 10 yr but reduce progress for the other traits by 8%.     

Probe diffusion in κ-carrageenan gels determined by fluorescence recovery after photobleaching

The effects of free volume and heterogeneity on probe diffusion in κ-carrageenan gels were determined by fluorescence recovery after photobleaching (FRAP) and rheology. By changing the ionic conditions, biopolymer concentration and end temperature, different microstructures and aggregation kinetics in the κ-carrageenan gels were evaluated. The results of the FRAP measurements were compared to transmission electron microscopy (TEM) and nuclear magnetic resonance diffusometry (NMRd) data from previous studies. The results showed that the free diffusion rates of the probe (FITC dextran) in water were influenced by both temperature and ionic conditions. The free diffusion values were used for normalization of the diffusion rates in the κ-carrageenan gel measurements. The compatibility between FITC dextran with different molecular weights (10 and 500 kDa) and κ-carrageenan was evaluated. The results showed that the larger FITC dextran probe phase separates; therefore only the 10 kDa FITC dextran probe was used in the FRAP experiments. FRAP measurements and NMRd probe diffusion in combination with TEM in κ-carrageenan revealed that the void space, degree of aggregation and heterogeneity influence the probe diffusion rate. The κ-carrageenan gelation was analyzed at different end temperatures using rheology and FRAP. The FITC dextran probe diffusion was not influenced by κ-carrageenan aggregation, regardless of rheological gelation kinetics and storage modulus near the gel point. This indicates that the average void space between the gel strands is larger than the size of the probe. Good correlation between the microstructure and the probe diffusion rate in κ-carrageenan gel with different ionic conditions and constant biopolymer concentration were obtained with TEM and FRAP.     

Genetic and environmental analysis of diseases with major economic impact in Israeli Holsteins

Incidences of ketosis, metritis, mastitis, and retained placenta were studied in Israeli Holstein cows calving between 2008 and 2017. These diseases were selected based on their economic impact. Ketosis, metritis, and retained placenta were scored dichotomously. Mastitis was scored as absent, a single occurrence during the lactation, or more than 1 occurrence. Ketosis and metritis were recorded during the first 21 d after calving, retained placenta during the first 5 d after calving, and mastitis up to 305 d in milk. The effects of herd-year-season, calving age, month of calving, gestation length, and occurrence of dystocia were included in the first-parity analysis models. All effects were significant for metritis and retained placenta. For ketosis, all effects were significant, except for gestation length. For mastitis, only the effects of herd-year-season and calving age were significant. Variance components were computed by the multitrait animal model. The 4 diseases were analyzed jointly based on first-parity records, and each disease was analyzed separately for parities 1 to 3 with the different parities considered separate traits. The 4 disease traits in first parity were also analyzed jointly with the 6 major traits included in the Israeli breeding index: milk, fat, and protein production; somatic cell score; female fertility; and longevity. Heritability was highest for metritis and lowest for mastitis, but all heritabilities were <0.07, similar to previous studies. For all 4 diseases, genetic correlations among the first 3 parities were >0.65, and all residual correlations were <0.07. Selection of herd-years assumed to have more accurate recording of mastitis did not result in higher heritability estimates. Genetic correlations between the disease traits and milk, fat, and protein production were economically unfavorable, while correlations between the disease traits and somatic cell score, female fertility, and longevity were economically favorable. Expected genetic changes in the disease traits after 10 yr of selection with the current Israeli breeding index were all <1%, except for ketosis, which was predicted to increase by 1.5%. Inclusion of these traits in a proposed index with the disease traits constituting 7% of the index would result in only marginal improvements for the disease traits and adversely affect genetic gain for fat and protein production. Thus, inclusion of these traits in the breeding index cannot be justified economically.     

Kinetics of oxytetracycline reaction with a hydrous manganese oxide

Tetracycline antibiotics comprise a class of broad spectrum antimicrobial agents finding application in human therapy, animal husbandry, aquaculture, and fruit crop production. To better understand the processes affecting these antibiotics in soils and sediments, the kinetics of oxytetracycline transformation by a hydrous manganese oxide (MnO2) were investigated as a function of reactant concentration, pH, and temperature. Oxytetracycline was rapidly degraded by MnO2. Initial reaction rates exhibited pronounced pH-dependence, increasing as pH decreased. Reaction of oxytetracycline with MnO2 was accompanied by generation of Mn(II) ions, suggesting oxidative transformation of the antibiotic. At pH 5.6, apparent reaction orders for oxytetracycline and MnO2 were 0.7 and 0.8. Reaction order with respect to H+ was 0.6 between pH 4 and 9. Initial reaction rates increased by a factor of approximately 2.4 for 10 degrees C temperature increases; the apparent activation energy (60 kJ x mol(-1)) was consistent with a surface-controlled reaction. Reactivity of tetracycline antibiotics toward MnO2 increased in the following order: rolitetracyline oxytetracycline < or =tetracycline approximately meclocycline < chlortetracycline. The initial rate of chlortetracycline degradation by MnO2 was substantially larger than that of the other tetracycline antibiotics investigated. MnO2 reactivity toward oxytetracycline decreased with time; a retarded rate equation was used to describe oxytetracycline reaction with MnO2 under declining rate conditions. This study indicates that natural manganese oxides in soils and sediments are likely to promote appreciable degradation of tetracycline antibiotics, and that reaction rates are strongly dependent on reaction time scale and solution conditions.     

Molecular and cellular effects of green tea on oral cells of smokers: a pilot study

Studies in cell culture and laboratory animals have shown that green tea and its major component, epigallocatechin-3-gallate, inhibit cell growth and reduce tumor incidence. However, results of epidemiological studies have generated inconsistent, sometimes conflicting data regarding protection by green tea against human cancers. To clarify the findings of these laboratory studies in application to humans, we conducted a pilot intervention study with three heavy smokers (> 10 cigarettes/day) and three nonsmokers (never smokers) in order to evaluate the molecular and cellular effects of drinking green tea using human oral cells as an investigative tool. Green tea total extract (400-500 mg/cup, 5 cups/day) was administered in drinking water to the subjects for four weeks. Two oral cytology samples were taken weekly for measurements of tobacco carcinogen-induced DNA damage, including bulky adducts and oxidized bases, cell growth, DNA content, and apoptosis. The study showed that during the course of green tea administration smoking-induced DNA damage was decreased, cell growth was inhibited, and the percentage of cells in S phase was reduced, cells accumulated in G1 phase (cyclin D1 positive), DNA content became more diploid and less aneuploid, and p53, Caspase-3, and TUNEL, markers of apoptosis, were increased. The study, although preliminary, indicates that drinking green tea reduced the number of damaged cells in smokers by inducing cell growth arrest and apoptosis, a mechanism similar to that observed in cultured cells and animals. These results warrant a large-scale intervention trial to further verify the role of green tea in the prevention of oral cancer in smokers.     

Adsorption of sulfonamide antimicrobial agents to clay minerals

Adsorption of three sulfonamide antimicrobials to clay minerals was investigated as a function of pH, ionic strength, and type of exchangeable cation. Sulfonamide antimicrobial adsorption exhibited pronounced pH dependence consistent with sorbate speciation and clay properties. Sulfonamide antimicrobials did not intercalate into montmorillonite, and surface charge density influenced sorption by determining adsorption domain size. Adsorption edge data were best fit to a model including terms for the cationic and uncharged species. Adsorption of uncharged sulfamethazine to montmorillonite was relatively insensitive to pH, ionic strength, and type of exchangeable cation, while that to kaolinite was highly sensitive to ionic strength. Adsorption of cationic sulfamethazine to montmorillonite exceeded that of the neutral species by 1-2 orders of magnitude, but was unimportant for kaolinite atthe pH values examined. Cation exchange appeared to contribute to sorption of cationic sulfonamide species to montmorillonite. Anionic sulfamethazine adsorption was negligible. The nature of the sulfonamide R group influenced the degree of adsorption of cationic and neutral species. Our results highlight the importance of considering sulfonamide speciation and clay surface charge density in predicting the transport of these antimicrobials.     

Behavior-change trials to assess the feasibility of improving complementary feeding practices and micronutrient intake of infants in rural Bangladesh

This study used simple rapid-assessment techniques to test the feasibility of increasing the consumption of complementary foods by infants by asking mothers to increase meal quantity or frequency or by altering the viscosity/energy density of the food. The feasibility of using micronutrient supplements either added directly to food or administered as liquid drops was also examined. The study was conducted in rural Bangladesh and involved four separate short-term behavioral change trials. Depending on the trial, fieldworkers recruited 30 to 45 infants 6 to 12 months of age. Following recommendations to increase the amount of food provided to infants, the mean intakes from single meals increased from 40 +/- 23 g on day 1 to 64 +/- 30 g on day 7 (p < 0.05). In a second trial, the mean meal frequency increased from 2.2 +/- 1.3 on day 1 to 4.1 +/- 1.3 on day 7 (p < 0.05). Provision of high-energy-density diets, prepared by decreasing viscosity with alpha-amylase or by hand-mashing rice and dhal into a paste before feeding, increased single-meal energy consumption from 54 +/- 35 kcal to 79 +/- 52 kcal or 75 +/- 37 kcal (p < 0.05), respectively. Both types of micronutrient supplements were well accepted and used according to recommendations. In conclusion, it was possible to change short-term child-feeding behaviors to promote increased food intake, mealfrequency, energy density, and micronutrient consumption. Because each of these interventions lasted for only about 1 week, however, the long-term sustainability of these changes is not known. Moreover, the effect of increased feeding of complementary foods on intakes of breastmilk and total daily consumption of energy and nutrients requires further study.     

Production and purification of a fused recombinant protein gp-36 (HIV-2) from Escherichia coli

A fragment of the gp-36 gene of the Human Immunodeficiency Virus type 2 (HIV-2) was fused to a stabilizer sequence, which encodes for the first N-terminal 58 amino acids of the human interleukin-2. The fused protein was expressed under the control of the tryptophan promoter in Escherichia coli, and expressed as 20% of the total cellular protein. Transmission electron microscopy indicated that the fusion protein formed cytoplasmic insoluble inclusion bodies. Inclusion bodies were semipurified by a wash pellet cell procedure, rendering a material with a purity higher than 70% by SDS–polyacrylamide gel electrophoresis. After solubilization with urea, this preparation was further purified by gel-filtration chromatography up to 95% purity.