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Livestock mature at different rates depending, in part, on their genetic merit; therefore, the optimal age at slaughter for progeny of certain sires may differ. The objective of the present study was to examine sire-level genetic profiles for carcass weight, carcass conformation, and carcass fat in cattle of multiple beef and dairy breeds, including crossbreeds. Slaughter records from 126,214 heifers and 124,641 steers aged between 360 and 1,200 d and from 86,089 young bulls aged between 360 and 720 d were used in the analysis; animals were from 15,127 sires. Variance components for each trait across age at slaughter were generated using sire random regression models that included quadratic polynomials for fixed and random effects; heterogeneous residual variances were assumed across ages. Heritability estimates across genders ranged from 0.08 (±0.02) to 0.34 (±0.02) for carcass weight, from 0.24 (±0.02) to 0.42 (±0.01) for conformation, and from 0.16 (±0.03) to 0.40 (±0.02) for fat score. Genetic correlations within each trait across ages weakened as the interval between ages compared lengthened but were all >0.64, suggesting a similar genetic background for each trait across different ages. Eigenvalues and eigenfunctions of the additive genetic covariance matrix revealed genetic variability among animals in their growth profiles for carcass traits, although most of the genetic variability was associated with the height of the growth profile. At the same age, a positive genetic correlation (0.60 to 0.78; SE ranged from 0.01 to 0.04) existed between carcass weight and conformation, whereas negative genetic correlations existed between fatness and both conformation (–0.46 to 0.08; SE ranged from 0.02 to 0.09) and carcass weight (–0.48 to –0.16; SE ranged from 0.02 to 0.14) at the same age. The estimated genetic parameters in the present study indicate genetic variability in the growth trajectory in cattle, which can be exploited through breeding programs and used in decision support tools.

Enteric ruminant methane is the most important greenhouse gas emitted from the pastoral agricultural systems. Genetic improvement of livestock provides a cumulative and permanent impact on performance, and using high-density SNP panels can increase the speed of improvement for most traits. In this study, a data set of 1,726 dairy cows, collected since 1990, was used to calculate a predicted methane emission (PME) trait from feed and energy intake and requirements based on milk yield, live weight, feed intake, and condition score data. Repeated measurements from laser methane detector (LMD) data were also available from 57 cows. The estimated heritabilities for PME, milk yield, DMI, live weight, condition score, and LMD data were 0.13, 0.25, 0.11, 0.92, 0.38, and 0.05, respectively. There was a high genetic correlation between DMI and PME. No SNP reached the Bonferroni significance threshold for the PME traits. One SNP was within the 3 best SNP for PME at wk 10, 20, 30, and 40. Genomic prediction accuracies between dependent variable and molecular breeding value ranged between 0.26 and 0.30. These results are encouraging; however, more work is required before a PME trait can be implemented in a breeding program.

The definition of the Metabolic Syndrome (MS) has encountered difficulty in reaching a universal consensus although there exists an agreement of its main pathologies which are hypertension, obesity, dyslipidemia, insulin resistance, inflammation and renal damage. The prevalent opinion is that three of those alterations may define the syndrome. The incidence of the MS has increased globally, particularly in the last few years, to the point of being regarded as an epidemic. The treatment of the MS can be approached from different angles, since it may be a multifaceted health problem. A healthy lifestyle, which means the practice of regular exercise is suggested to MS patients. Increasing physical activity has anti-inflammatory effects since there is an inverse association of physical activity and inflammatory biomarker concentrations. An adequate diet is recommended, such as the Mediterranean, which contains fish, tomatoes, garlic, red peppers, olive oil and includes red wine, that is, antioxidants and non-saturated oils. There are also the traditional herbal preparations, used in the alternative medicine. Several therapeutic tools can be used; the most common are the pharmaceutical products to deal with obesity, hypertension, dyslipidemias, diabetes and inflammation. In addition several pharmacological therapies such as non steroidal anti-inflammatory drugs are recommended. Recently new mechanisms of action of statins, fibrates, metformin and thiazolidinediones have demonstrated their anti-inflammatory effect and potential use to treat MS.

Genomic selection is rapidly becoming the state-of-the-art genetic selection methodology in dairy cattle breeding schemes around the world. The objective of this paper was to explore possibilities to apply genomic selection for traits related to dairy cow robustness. Deterministic simulations indicate that replacing progeny testing with genomic selection may favour genetic response for production traits at the expense of robustness traits, owing to a disproportional change in accuracies obtained across trait groups. Nevertheless, several options are available to improve the accuracy of genomic selection for robustness traits. Moreover, genomic selection opens up the opportunity to begin selection for new traits using specialised reference populations of limited size where phenotyping of large populations of animals is currently prohibitive. Reference populations for such traits may be nucleus-type herds, research herds or pooled data from (international) research experiments or research herds. The RobustMilkproject has set an example for the latter approach, by collating international data for progesterone-based traits, feed intake and energy balance-related traits. Reference population design, both in terms of relatedness of the animals and variability in phenotypic performance, is important to optimise the accuracy of genomic selection. Use of indicator traits, combined with multi-trait genomic prediction models, can further contribute to improved accuracy of genomic prediction for robustness traits. Experience to date indicates that for newly recorded robustness traits that are negatively correlated with the main breeding goal, cow reference populations of ?10 000 are required when genotyping is based on medium- or high-density single-nucleotide polymorphism arrays. Further genotyping advances (e.g. sequencing) combined with post-genomics technologies will enhance the opportunities for (genomic) selection to improve cow robustness.

Variation in sexual dimorphism (SD) is particularly marked in meat-type chickens. This paper investigates the genetic basis of SD in an important economic trait, i.e. body weight (BW) at 35 days of age, in broilers by applying quantitative genetic analysis. A large dataset comprising 203,323 BW records of a commercial line of broiler chicken was used. First, a bivariate approach was employed treating BW as a sex-specific trait. During this approach, seven bivariate models were applied and variances due to direct additive genetic, maternal genetic and maternal environmental effects were estimated via the restricted maximum likelihood method. The best-fitting model included direct additive genetic, maternal genetic and maternal environmental effects with a direct–maternal genetic covariance. Differences between male and female direct heritabilities were non-significant (0.28 vs. 0.29 for males and females, respectively), implying no need for sex-specific selection strategies. The direct–maternal genetic correlation was more strongly negative in males than in females (−0.72 vs. −0.56), implying a more profound antagonism between direct additive and maternal genetic effects in this particular gender. The direct genetic correlation of BW between the two sexes was as high as 0.91, i.e. only slightly lower than unity. Second, variance components and genetic parameters of two measures of SD, i.e. the weight difference (Δ) and the weight ratio (R), between the genders were estimated. Direct heritabilities for both measures were significantly different to 0 but of low magnitude (0.04). Apart from the additive–maternal covariance, no other random effects were found to be of importance for Δ and R. The results of the present study suggest that only minimal selection responses due to the selection of Δ and/or R and a small capacity for amplifying or reducing the BW differences between the sexes are to be expected in this specific population. Furthermore, selection pressure on BW is expected to amplify SD.Variation in sexual dimorphism (SD) is particularly marked in meat-type chickens. This paper investigates the genetic basis of SD in an important economic trait, i.e. body weight (BW) at 35 days of age, in broilers by applying quantitative genetic analysis. A large dataset comprising 203,323 BW records of a commercial line of broiler chicken was used. First, a bivariate approach was employed treating BW as a sex-specific trait. During this approach, seven bivariate models were applied and variances due to direct additive genetic, maternal genetic and maternal environmental effects were estimated via the restricted maximum likelihood method. The best-fitting model included direct additive genetic, maternal genetic and maternal environmental effects with a direct–maternal genetic covariance. Differences between male and female direct heritabilities were non-significant (0.28 vs. 0.29 for males and females, respectively), implying no need for sex-specific selection strategies. The direct–maternal genetic correlation was more strongly negative in males than in females (−0.72 vs. −0.56), implying a more profound antagonism between direct additive and maternal genetic effects in this particular gender. The direct genetic correlation of BW between the two sexes was as high as 0.91, i.e. only slightly lower than unity. Second, variance components and genetic parameters of two measures of SD, i.e. the weight difference (Δ) and the weight ratio (R), between the genders were estimated. Direct heritabilities for both measures were significantly different to 0 but of low magnitude (0.04). Apart from the additive–maternal covariance, no other random effects were found to be of importance for Δ and R. The results of the present study suggest that only minimal selection responses due to the selection of Δ and/or R and a small capacity for amplifying or reducing the BW differences between the sexes are to be expected in this specific population. Furthermore, selection pressure on BW is expected to amplify SD.

In the metabolic syndrome (MS), a condition that associates three or more pathologies such as hypertension, central obesity, type II diabetes, insulin resistance and dyslipidemias, the kidneys are severely affected. The pathological alterations in the kidneys, associated with MS, may be modified by sex hormone levels. In general, estrogens are a protection against the development of cardiovascular and renal diseases in humans and experimental models, but androgens may have an opposite effect. Among the metabolic systems that can be modulated by sex hormones in the kidney, the more important are: renin-angiotensin-aldosterone system, arachidonic acid metabolism, nitric oxide system and renal extracellular matrix proteins. These are metabolic pathways normally associated, in order to maintain the most efficient functioning of renal hemodynamics. There is a close interrelationship between sex hormones and some pathways involved in the metabolic syndrome; also pathways can modulate each other. The circulating concentrations of hormones may determine the degree of overall pathological alterations in the syndrome.

The metabolic syndrome (MS) has become the new epidemic of this century. Although its associated pathologies may vary, the most common are hypertension, central obesity, dyslipidemia, low High Density Lipoproteins (HDL), high Low Density Lipoproteins (LDL), and type-2 diabetes. Several others can be present, such as hypertriglyceridemia, cardiopathies, atherosclerosis, altered levels of sex hormones, hypogonadism in men and nephropathy. Several factors such as gender, age, race, lifestyle and diet may contribute to modify its prevalence: men develop cardiovascular diseases at an earlier age than pre-menopausal women, who seem to be protected by the antioxidant properties of estrogens. The present review offers information, mostly from 2008 to the present, as well as our own work on a rat model of MS, which was developed by the administration of sucrose in drinking water. Sex steroid hormones play an important role in the appearance and development of the MS and of cardiovascular diseases. Variations in the levels of sex hormones, whether normal or pathological, may have significant influence in the onset of several diseases, metabolic syndrome components included, as well as in the behavior of tissues and organs. These are just some of the non-reproductive actions of sex hormones.

The metabolic syndrome (MS) has become a worldwide health problem. It is difficult for patients to follow a diet/exercise regime that would improve their symptoms, therefore the investigation of agents that may deal with its more serious aspects is an important medical field for research. The cardiovascular consequences associated with the syndrome and some of the therapeutic approaches are discussed. The different agents can be divided into several groups: Inorganic/ organic: Zinc complexes with garlic components as insulino-mimetics; Selenium as antioxidant; Copper, Zinc and Manganese as microcomponents of antioxidant enzymes. Organic: Natural or Synthetic: Glycine is effective in lowering blood pressure, TBARS, intra-abdominal fat tissue and triglycerides in sucrose-fed rats. Pharmaceutical products: Fibrates, Lipid-lowering drugs. Antidiabetics. Anti-gout agents On the other hand there are natural products such as those of animal origin: Sex hormones (also synthetic) used in the problems of menopause and hypoandrogenism frequently found in the MS, antioxidant Omega-3-oils (fish oils) or Vegetal: for example Digitalis pupurea, century-old cardiovascular medication as well as Magnolia officinalis; Spirulina maxima with beneficial effects as antioxidant and lipid-lowering agent, among others. Prickly Pear Cacti. (Opuntia Ficus- Indica Cochlospermum vitifolium (Willd.) Spreng) whose many properties against diabetes and hypercholesterolemia have been empirically known for many years. Perezone (from Perezia plants, a.k.a. Peonia) described as an antiplatelet aggregating agent. The mixed elements in the Mediterranean diet: Fish, salads (peppers, tomatoes), olive oil, garlic, red wine which combines fish oils, garlic and avocado as well as antioxidants from the rest of its components.

The eating quality of lamb meat of three indigenous Greek dairy breeds of sheep, reared under different nutritional management conditions, was assessed by Taste Panel Tests (TPT). Lean samples from the leg joints of 69 lamb carcasses of the Boutsko (B), Serres (S) and Karagouniko (K) breed were used. For the first TPT, 24 lambs (four males and four females of each breed) were reared in individual pens on a concentrate ration fed ad libitum. For the second TPT, 27 individual penned male lambs were fed on Lucerne hay ad libitum and on three different levels of concentrate: High (H), Medium, (M) and Low (L). For the third TPT, 18 male lambs were used; initially the groups were fed indoors for 63 days on three different levels of concentrate (H, M and L) together with ad libitum Lucerne hay, and subsequently finished on irrigated, sown pasture. For TPT 1, leg joints were obtained from lambs that had been slaughtered at 30, 45, 60 or 90% of mature weight (PMW) for each breed. For TPT 2, lambs were slaughtered at 23, 28 or 33 kg target slaughter live weights (TSLW), common for all breeds. For TPT 3, lambs were slaughtered at 48 or 55% of PMW for each breed. Panellists assessed warm, roasted lean samples of leg joints and rated Flavour, Juiciness, Tenderness and Overall Acceptability. In TPT 1, degree of maturity significantly affected Flavour, Tenderness and Overall Acceptability whereas sex affected only Flavour. In TPT 2, breed and concentrate level significantly affected the quality characteristics, but concentrate level had no significant effect in TPT 3. Effects associated with slaughter weight were significant for most characteristics in all TPT, with decreasing acceptability for older/heavier lambs. Significant interactions were found between breed and the other factors in TPT 2 and TPT 3 for most quality characteristics. Results from these studies suggest changing traditional production systems may enhance the eating quality of lamb meat.

The impact of paternity identification errors on US genetic evaluations and international comparisons of Holstein dairy bulls for milk, fat, and protein yields was investigated. Sire identification was replaced for 11% of Holstein cows that were sired by AI bulls and had records in the US database for national genetic evaluations; US evaluations were computed based on those modified pedigrees and compared with official national evaluations. Estimated breeding values from the data with introduced paternity errors were biased, especially for later generations. Estimated genetic trends decreased by 11 to 15%. Estimates of standard deviations of sire transmitting ability also decreased by 8 to 9%. International multitrait across-country comparisons of bulls were computed based on national evaluations from the United States, Canada, New Zealand, and The Netherlands. Estimates of genetic correlations between the United States and other countries decreased by 0.04 to 0.06 when US evaluations were based on modified pedigree. The resulting bias toward selection of domestic bulls and the inability to identify truly superior animals that are available internationally could decrease potential selection differentials by 0.07 to 0.09 standard deviation units on the US scale, which corresponds to sire breeding values of approximately 50kg for milk, 3kg for fat, and 1.7kg for protein. Losses for the other countries were lower and ranged from 0.02 to 0.05 standard deviation units, because a correlation of less than unity with the United States decreased the impact of US cow paternity errors on the scales of other countries. Although paternity verification is desirable and technically feasible, commercial implementation would require low testing costs.

International genetic evaluations of dairy bulls are currently based on national genetic evaluation results. Total number of daughters in a country is used to weight national information, but may not optimally reflect the precision of a sire's daughter contribution to international genetic evaluations. This study investigates the impact of alternative weighting factors on international evaluation results. A conventional progeny test scheme was simulated for two dairy cattle populations, with semen exchange at a fixed rate after each generation. True breeding values for both populations were generated as bivariate normal deviates. Each cow had three lactation records in one country only. After 10 generations of selection, all records were used in national breeding value prediction. National breeding values of bulls were used as input to international evaluations. Seven different weighting factors were evaluated: 1) total number of daughters; 2) total number of lactations; 3) as (one) also adjusted for finite contemporary group size; 4) as (three) also adjusted for distribution of daughters over contemporary groups; 5) effective daughter contribution considering finite contemporary group size and correlation between repeated records; 6) as (five) also considering the reliability of the daughter dam evaluation; and 7) as (five) also considering the reliability of the daughter female ancestors’ evaluations. Using the last two weighting factors yielded empirically unbiased estimates of sire variance. Using total number of daughters overestimated genetic variance by up to 7%. In general, international breeding values were marginally affected by choice of weighting factor. The effect was larger when different national evaluation models had been applied in the two countries. International reliabilities for the last two weighting factors were close to expectation, whereas using total number of daughters resulted in 1 to 4% negative bias. In practice, different countries apply a wide range of national evaluation models, and genetic ties may be weak between some populations, thereby increasing the potential effect of weighting factors on international comparisons. The weighting factor developed in this study, which considers contemporary group structure, correlation between repeated records, and reliability of dams of daughters, should replace total number of daughters in international genetic evaluations of dairy sires.

National and international Holstein bull evaluations from Canada, France, Germany, Italy, The Netherlands, and the US were examined to determine whether inclusion of data from other countries increased the accuracy of prediction of national evaluations for milk, fat, and protein yields. The six national and six international evaluations from February 1995 were compared with national evaluations in January and February 1999. The later national evaluations were assumed to be improved estimates of true genetic merit because of added data. Correlations with later national evaluations generally were larger for earlier national evaluations than for international evaluations, probably because of the larger part-whole relationship between earlier and later national evaluations. However, standard deviations of difference of 1995 evaluations from later national evaluation were lower for international evaluations than for earlier national evaluations, which suggested improved prediction from inclusion of multinational data. For bulls with substantial increases in daughters, nationally and internationally, correlations were higher, and standard deviations of differences were lower for international evaluations compared with earlier national evaluations. Inclusion of multinational data improved the prediction of future national evaluations, especially for countries that import genetics of dairy cattle.

Sire genetic evaluations for protein yield, productive life, and selected type traits from the US were correlated with sire evaluations for disease from Denmark and Sweden and were then adjusted to approximate genetic correlations. Disease categories from Denmark included reproductive diseases, foot and leg diseases, metabolic and digestive diseases, and all diseases other than mastitis. Genetic evaluations for Denmark were from separate analyses for each disease category using a multiple-trait sire model with first, second, and third lactations handled as multiple traits. Evaluations from Sweden for all diseases other than mastitis were from a single-trait sire model using only first lactations. In addition, Danish and Swedish genetic evaluations were regressed on US type evaluations to test for quadratic relationships. Relationships were based on 104 bulls with US and Danish evaluations (88 with US type) and 84 bulls with US and Swedish evaluations (83 with US type). Genetic correlations between US protein yield and diseases were unfavorable, but correlations were favorable between productive life and disease. Genetic correlations among US type and diseases were around zero, except for correlations with US dairy form (range –0.34 to –0.73). Genetic correlations calculated from residual correlations (adjusted for predicted transmitting abilities for milk) between productive life and diseases were favorable (range 0.29 to 0.51). Genetic correlations calculated from residual correlations (adjusted for predicted transmitting abilities for milk) between dairy form and diseases ranged from –0.10 to –0.53. Selection for increased productive life may reduce disease occurrences, but selection for higher dairy form scores will increase disease occurrences.

Sire genetic evaluations for protein yield, somatic cell score (SCS), productive life, and udder type traits from the US were correlated with sire evaluations for udder health from Denmark and Sweden and then the correlations were adjusted for accuracies to approximate genetic correlations. Traits from Denmark and Sweden included somatic cell count (SCC) and clinical mastitis from single-trait analyses. In addition, evaluations for clinical mastitis from Denmark and Sweden were regressed on US traits to test for quadratic relationships. Information from 85 bulls with US and Danish evaluations (77 with US type) and from 80 bulls with US and Swedish evaluations (79 with US type) was used to calculate correlations. Genetic correlations of US protein yield with Danish and Swedish SCC and clinical mastitis were all unfavorable (–0.09 to –0.32). Genetic correlations of US productive life with Danish and Swedish SCC and clinical mastitis were all favorable (0.06 to 0.59). Genetic correlations between US SCS and Danish SCC and between US SCS and Swedish SCC were –0.87 and –0.99, respectively (favorable). Genetic correlations between US SCS and Danish clinical mastitis and between US SCS and Swedish clinical mastitis were –0.66 and –0.49, respectively (favorable). The US type traits that had the largest correlations with clinical mastitis from Denmark and Sweden, respectively, were udder composite (0.26, 0.47), udder depth (0.45, 0.52), and fore udder attachment (0.31, 0.34). In general, quadratic regressions indicated little nonlinearity between clinical mastitis and the US traits. Specifically, the US bulls with the lowest predicted transmitting abilities for SCS had the most favorable rates of daughter clinical mastitis in Denmark and Sweden. Selection for increased productive life, lower SCS, and more shallow udders should improve mastitis resistance.

Increased international trade of genetic material from dairy cattle requires genetic evaluations across countries. Methods are discussed for comparing genetic evaluations of bulls computed in different countries. A system that combines information from several countries and produces routine international evaluations of dairy bulls is described, and possible ways of utilizing such international information in national breeding programs are presented. Important issues for international genetic evaluations are the estimation of genetic parameters within and across countries and the impact of imported bull evaluations on international rankings. Both issues are discussed in this article in view of recent research findings and potential future applications. Optimally, routine systems for international evaluation of the future will consider all economically important traits and serve different and well-defined breeding goals.

The relative rate of calcium transport into platelets from essential hypertensive patients and healthy normotensive donors was measured using the metallochromic indicator arsenazo III and recording net decrease in optical density per 5 minutes (O.D.U./ 5 min). When platelets from essential hypertensive patients were suspended in the patient's own serum, calcium was transported more rapidly than when suspended in normal sera (0.0166 vs 0.0113 O.D.U./ 5 min, P < 0.01) indicating that the difference is due to a circulating factor. When platelets from healthy normotensive volunteers were suspended in the donor's own serum or in a pool of normal sera, the relative rate of transport was lower than in the case of platelets from hypertensives suspended in the pool of normal sera (0.005 vs 0.0113 O.D.U./ 5 min, P < 0.01) which suggests a membrane alteration rendering the platelets from hypertensives more permeable to calcium. It was observed that the increase of calcium entry was inhibited by verapamil.The nature of these circulating and membrane-associated factors is at present unknown, but the circulating factor was capable of increasing the membrane permeability to calcium in normal human platelets (from 0.0057 to 0.011 O.D.U./5 min, P < 0.01) and even in rat liver mitochondria, an effect that was inhibited by ruthenium red.

Genetic evaluations within and across populations (countries, breeds, herds) allow ranking on estimated genetic merit and selecting breeding individuals across populations. Selection within and across populations (combined selection) should by definition always be as good as, or better than, within-population selection, the limiting case. The advantage depends on the sizes of the populations, the number of populations, the initial genetic means, and the correspondence of the breeding objectives in the different populations, as measured by the genetic correlation for economic merit. The advantages of combined selection are evaluated deterministically for a simple case of selecting the best males for use across populations by using a common truncation line over the distributions of EBV for the different populations. Combined selection increases overall response rates in the cooperating populations. Where the initial genetic means are the same, small populations (100 males tested) benefit greatly from combined selection. Large populations (500 to 1,000 males tested) also benefit, but less. The results depend on the increased selection response to scale, response being approximately linear with the logarithm of the number tested. When the initial means differ, the genetically poorer population can catch up in three to five generations and then contribute to the increased responses with combined selection. When breeding objectives differ, selection usually gradually pulls the populations apart and they make less and less contribution to each other and finally become separate. These results have implications for breeding strategies. Their application would affect structures of populations and rates of genetic change possible by selection.

A developing active region near the center of the solar disk was observed for 80 min at the center and the wings of Ha. Ellerman bombs lying both below an Arch Filament System and near sunspots were studied at Ha - 1.0 Å and Ha - 0.75 Å. We determined their average contrast, lifetime, size and we studied their flux as a function of time. We found evidence that the size of Ellerman bombs increases with height. The time curves of flux provide evidence for both impulsive and gradual energy release. Under the AFS the Ellerman bombs form a cellular pattern with a characteristic size of 3.1 × 103 km. Fifty percent of the bombs appear and disappear in pairs, possibly associated with bipolar emerging magnetic flux tubes.

Simulation was used to examine the changes that may occur in international dairy sire evaluations when differing amounts of historical performance data are used. When the base genetic variances within each population were equal, use of all historical data in international sire evaluations gave unbiased predictions for breeding values. When some historical data from one population were discarded, the estimated genetic standard deviation for this population was reduced because of the effects of genetic selection, and slope coefficients of conversion equations were biased slightly in favor of this population. When base genetic variances differed among populations, the use of all historical performance data in international sire evaluations resulted in substantial upward bias in evaluations of elite sires from the importing population. This result occurred because the estimated genetic standard deviation in the importing population was reduced by inclusion of performance data from many older bulls from the breed or strain that was being replaced. When performance data from bulls that were born prior to the beginning of importation were discarded, estimated parameters for genetic standard deviation were similar for both populations, and estimated breeding values of elite bulls were very close to the true values. This research suggests that accuracy of international dairy sire evaluations may be improved by discarding historical performance data of bulls from breeds or strains that have been replaced by imported stock.

The methods used and the results obtained in the measurement of the distances between the centers of chromospheric granules are described. A coincidence of these structures at two different altitudes was observed. Observations made in the K2v, or in the K3 and CN lines permit the comparison of two different altitudes: the upper and the lower chromosphere. These results include flocculi on the edge of the supergranules as well as plages. Two main results are obtained: (l)the most likely distance between two neighboring granules is, at the minimum of the solar cycle, of about 2?. 60 for K3 and 2?.45 for CN, and (2) this distance is decreasing with growing solar activity.

Some properties of the solar spicules as observed outside the limb through a Halle K-filter at the centre of the line are investigated. The observations have been made at the Pic-du-Midi Observatory. The results are as follows: (a) The chromosphere at the limb appears more diffuse in the K line than in the Ha line, the spicules being not well resolved. (b) The ratio of spicule intensity to the background intensity increases with height, as in the case of Ha spicules, but it is, in every height, smaller than that in Ha. (c) The spicule mean width is measured photometrically and found equal to 1900 km. (d) The lifetime is found to be 4.5 min. (e) The mean chromospheric height is estimated to be 6.000 km.

High resolution photographs of the solar chromosphere have been obtained with the 40-cm refractor of the Athens Observatory and a 0.5 Å ‘Halle’ Hα filter. Our best photographs show a resolution of 0″.6, which is comparable with the theoretical resolving limit of 0″.4, at Hα. The achieved resolution permitted us to secure some excellent observations of the fine structure of the chromosphere on the disk as well as on the limb. The study of these observations leads to the following results: (a) the bright filaments of the disturbed chromosphere as well as the penumbral ones appear to consist of knots, (b) inside the cells of the chromospheric network of the quiet chromosphere, bright roundish granule-like formations are present, their mean size being of the order of 2500 km. (c) the bright fine mottles seem to lie at the root of the elongated dark ones, each pair of them giving rise to a spicule.

Une éruption d'importance 2 a été observée le 4 octobre 1965 à l'aide de l'héliographe à longueur d'onde variable de l'Observatoire de Meudon, qui fournit des images au centre et dans les ailes de la raie Ha. On étudie les phénomènes enregistrés en Ha, en relation avec les observations radioélectriques et le champ magnétique longitudinal de la région active associée.

AbstractGenetic evaluation for production traits in the Holstein breed in Italy has been based on a Random Regression Test Day Model (RRTDM) since November 2004. More specifically, the model is a multiple lactation, multiple trait RRTDM, similar to the model used in Canada for official genetic evaluation.Fixed regression curve effect include time, region, age at calving, parity and season of calving. Last changes in the model included a new definition of the proof scale and of the genetic base.The accuracy of the model was assessed by analyzing residuals and testing Mendelian sampling trends. Residuals were normally distributed for all traits and had zero mean.Residual trends for all the effects included in the model were analyzed also for effects not included in the model like number of milkings per day and number of days pregnant at the test date. Mendelian sampling did not show any significant trend over time both for cows and bulls.