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The aim of this study was to determine the lactation curve traits of Anatolian buffaloes raised under different conditions in farms in Tokat Province, Turkey. Wood’s gamma curve parameters were employed to identify the lactation curve types, and values for the parameters beginning yield (a), coefficient of rising (b) and coefficient of decreasing (c) were used to determine the shape and type of lactation curve. All parameters in typical lactation curves were positive, and in the event of one parameter being negative, the curve was considered to be an atypical lactation curve. A total of 690 lactation curves were investigated. It was determined that 406 (58.84%) of these curves were typical, while 90 (13.04%) were concave and 194 (28.12%) of a decreasing type. For typical lactation curves, a, b, c, persistency (S), time after parturition until the peak yield occurs (Tmax), maximum daily peak yield (Ymax), and coefficient of determination (R2) were 7.14±0.008, 0.85±2.1, 0.40±0.001, 2.68, 63.6, 6.41 and 76.33, respectively. For concave lactation curves, values for a, b, c, Tmax, Ymax and R2 were 4.94±0.42, -0.73±0.016, - 0.23±0.0038, 95.40, 7.41±0.004 and 71.68, respectively. For decreasing typical lactation curves, values for a, b, c, Tmax, and R2 were 5.31±0.0041, -0.15±0.007, 0.039±0.0023, 3.89±0.11 and 79.94, respectively. Parameters predicted by the Wood model within the scope of this study have the potential of being useful for breeding programmes. Further breeding/selection activities could be conducted by using the female Anatolian buffaloes with typical lactation curves.

This study was aimed to evaluate genetic diversity for drought tolerance and persistency of Iranian and foreign germplasm of orchardgrass. Thirty six genotypes of orchardgrass were clonally propagated and grown in the field under two moisture environments (normal and drought stress) for 3 years (2013-2015). High genotypic variation was observed among genotypes for all the measured traits, indicating a high potential for improving traits. Drought stress had negative effects on most of the measured traits and reduced genotypic variation. Low heritability for forage yield (average 21 %) suggested that indirect selection based on components of forage yield which had moderate to high heritabilities and high correlation with yield would be more effective. However, the order of priority of these components and their direct and indirect effects was different for normal and drought stress conditions. This suggested that indirect selection for development of high yielding drought-tolerant varieties should be performed under non-stress environment with a specific model. The results of principal component analysis showed that there was a negative relationship between phenological traits (days to ear emergence and days to anthesis) with the traits related to persistency and yield production. This indicates that selection for earliness in orchardgrass can improve productivity and persistency in orchardgrass. Contrasting genotypes were identified by biplot method that is useful for development of genetic populations for breeding studies of drought tolerance and persistency in orchardgrass. [ABSTRACT FROM AUTHOR]

This paper is motivated by the following question: How to construct good approximation for the distribution of the solution value to linear optimization problem when the random objective coefficients follow a multivariate normal distribution? Using Stein's Identity, we show that the least squares normal approximation of the random optimal value can be computed by estimating the persistency values of the corresponding optimization problem. We further extend our method to construct a least squares quadratic estimator to improve the accuracy of the approximation; in particular, to capture the skewness of the objective. Computational studies show that the new approach provides more accurate estimates of the distributions of project completion times compared to existing methods. [ABSTRACT FROM AUTHOR]

Background: In the US, the approved multiple sclerosis (MS) oral disease-modifying therapies (ODMTs) are fingolimod (FTY), teriflunomide (TFN), and dimethyl fumarate (DMF). FTY and TFN are recommended with once-daily doses with no up-titration, whereas DMF treatment is recommended twice-daily (BID) and is initiated with a 7-day starter dose of 120 mg BID before up-titration to the maintenance dose of 240 mg BID. Limited information exists regarding real-world ODMT prescribing patterns to aid physician/patient decision-making. Methods: Eligible patients for this retrospective medical record review were ≥18 years, had one visit related to ODMT initiation (index visit), and ≥1 visit within 12 months before and after the index visit. Primary objectives were to assess post-index ODMT persistency (i.e., discontinuation), prescribing patterns (medication switching, dose uptitrations, dose reduction, re-starts, and add-ons) and medical resource utilization (office-visits, MRI procedures, and mobility indicators) at distinct time windows of 3, 6, 9, and 12 months. Chi-square or Wilcoxon Rank Sum tests were used for 3-way ODMT group comparisons. Results: Medical records of 293 MS-diagnosed patients using ODMTs were abstracted from 19 US-based neurology clinics between December 31, 2010 and June 30, 2014 (FTY: 101; DMF: 133; TFN: 59). Persistency rates among ODMT groups were similar. MS-related medication switching, dose reduction, re-starts, and add-ons were infrequently observed and were similar across ODMT groups. Of DMF patients with a confirmed starting dose of 120 mg BID with ≥12 months follow-up (n = 26), the percentage who were prescribed dose up-titrations to the recommended maintenance DMF dose was 23.1 % at 1–3 months, 26.9 % at 4–6 months, 42.3 % at 7–9 months, and 0 % at 10–12 months. There were no significant differences at any time window among the ODMT groups in the number of office visits or percent of patients receiving MRIs. Mobility indicator patterns (proportion of patients with abnormal gait, wheelchair use, etc.) were consistent over time. Conclusions: There was no difference in persistency, prescribing patterns (medication switching, dose reduction, re-starts, and add-ons) or medical resource utilization (office-visits, MRI procedures, and mobility indicators) among the ODMTs. However, in a small sub-group of patients, delays of up to 9 months in DMF dose-up titration to the recommended maintenance dose were observed. [ABSTRACT FROM AUTHOR]

Genetic and phenotypic parameters were estimated for first parity Holstein cows with records from April 1991 to May 2006 for 305-d milk (Milk305), fat (Fat30 5), and protein (Pro305) yields, fat (Fat%) and protein (Pro%) percentage, productive life (PL), natural logarithm of soma tic cell score (LSCS), lactation length (LL) and milk (Milk3:1), and fat (Fat3:1) persistency. The (co)vari ance components and genetic pa rameters were estimated using restricted maximum likelihood (REML) method. Among production traits , the highest heritability (0.26) was for Fat% and the lowest one (0.048) was for Fat3:1 persistency. Heritability estimate for PL was low (0.035). Genetic correlations of PL with production traits were relatively high and positive (except for Fat% and Pro%). PL had the highest genetic correlation with Fat3:1 and Milk3:1 persistency (0.56 and 0.45, respectively). In general, phenotypiccorrel ations between traits were lower than genetic correlations. Milk3:1 and Fat3:1 persistency had favorable genetic correlation with LSCS (-0.34 and -0.36, respectively). It can be suggested to include a combination of production and persistency traits in selection index in order to increase PL and improve udder health. [ABSTRACT FROM AUTHOR]

En las comunidades vegetales, el banco de semillas en el suelo (BSS) constituye el potencial regenerativo. La reposición de los individuos a partir del BSS puede tener un efecto marcado en la composición y en los patrones de vegetación de la comunidad. Numerosas investigaciones se han llevado a cabo en bancos de semillas en hábitats agrícolas o en comunidades naturales. Esta revisión tiene como objetivo analizar los conceptos relacionados a BSS, los procesos de formación de éstos, las implicancias agrícolas y cómo esta información puede ser usada para la conservación de los sistemas productivos.In plant communities, the soil seed bank (SSB) represents their regenerative potential. The replacement of individuals from the seed bank may have profound effects on the composition and patterns of the vegetation within the community. Many investigations about seed banks have been made within agricultural habitats or in natural communities. The attempt of this review about the seed banks in the soil is to analyze the concepts related to SSBs, their formation, the agricultural implications and how this information might be used for the conservation of the productive systems.

We consider the energy minimization problem for undirected graphical models, also known as MAP-inference problem for Markov random fields which is NP-hard in general. We propose a novel polynomial time algorithm to obtain a part of its optimal non-relaxed integral solution. Our algorithm is initialized with variables taking integral values in the solution of a convex relaxation of the MAP-inference problem and iteratively prunes those, which do not satisfy our criterion for partial optimality. We show that our pruning strategy is in a certain sense theoretically optimal. Also empirically our method outperforms previous approaches in terms of the number of persistently labelled variables. The method is very general, as it is applicable to models with arbitrary factors of an arbitrary order and can employ any solver for the considered relaxed problem. Our method's runtime is determined by the runtime of the convex relaxation solver for the MAP-inference problem. [ABSTRACT FROM PUBLISHER]

Extending lactation by voluntarily delaying rebreeding aims to improve fertility and milk production in the modern dairy cow. Previous studies have shown that increased energy concentrations in the ration induced greater total milk yield and lactation persistency defined by the duration and the shape of the lactation curve. In this paper, we hypothesized that increasing the supply of energy during the early lactation mobilization period would have a positive carryover effect on milk production during extended lactation. A total of 53 Holstein cows completed a 16-mo lactation, including 30% primiparous cows. The cows were divided into 2 feeding strategies: half of the cows received a highenergy density diet (HD) in early lactation followed by a lower-energy density diet (LD; strategy HD-LD). The change in diet was defined individually after 42 d of lactation, and when the live weight (LW) gain of the cow was ≥0 based on a 5-d average. The other half of the cows were fed the LD diet during the entire lactation (strategy LD-LD). Both groups received 3 kg of concentrates per day during milking. Weekly milk composition (fat, protein, lactose, and somatic cells), daily milk production, daily feed intake, daily LW, and body condition score every second week were recorded. The fda package of R was used to model the curves of these different variables for the 53 cows that had a lactation over 400 d. The fitted values of these curves and the associated slopes were then compared for parity and treatment effects using a linear mixed-effects model. The HD-LD and LD-LD cows had a similar length of lactation (461 ± 7 d). The HD diet reduced the intensity of the mobilization period and increased the milk production of the multiparous cows in early lactation compared with the cows fed the LD diet. The primiparous cows used the extra energy to grow and gain weight, but not to produce more milk. After the shift in diet, the treatment had little short-term carryover effect on milk yield or LW, but it affected the slopes of some curves. From 0 to 50 d from shift, milk fat content of the LD-LD cows decreased faster than that of the HD-LD cows whereas milk lactose increased. From 250 to 350 d from shift, the energy-corrected milk decreased faster for the HD-LD cows than for the LDLD cows. The lactose content in milk decreased faster for the LD-LD cows than for the HD-LD cows, and the fat content in milk was significantly higher for the primiparous HD-LD than for the primiparous LD-LD cows. In conclusion, the supply of extra energy during the mobilization period had a 300-d negative carryover effect on lactation persistency. [ABSTRACT FROM AUTHOR]

We address combinatorial problems that can be formulated as minimization of a partially separable function of discrete variables (energy minimization in graphical models, weighted constraint satisfaction, pseudo-Boolean optimization, 0–1 polynomial programming). For polyhedral relaxations of such problems it is generally not true that variables integer in the relaxed solution will retain the same values in the optimal discrete solution. Those which do are called persistent. Such persistent variables define a part of a globally optimal solution. Once identified, they can be excluded from the problem, reducing its size. To any polyhedral relaxation we associate a sufficient condition proving persistency of a subset of variables. We set up a specially constructed linear program which determines the set of persistent variables maximal with respect to the relaxation. The condition improves as the relaxation is tightened and possesses all its invariances. The proposed framework explains a variety of existing methods originating from different areas of research and based on different principles. A theoretical comparison is established that relates these methods to the standard linear relaxation and proves that the proposed technique identifies same or larger set of persistent variables. [ABSTRACT FROM AUTHOR]

Animal selection in dairy cattle can vary depending on the objectives of the breeding programs. The objective of this study was to explore the genetic curve pattern of EBVs for test day milk yields (TDMY) in Holstein cows using cluster analyses to identify the most suitable animals for selection based on their genetic curve for milk yield. A data set with 29,477 monthly TDMY records from 3543 first lactations of Brazilian Holstein cows were used to predict the breeding values for TDMY with random regression model. Hierarchical and non-hierarchical cluster analyses were performed based on the EBVs for 30, 60, 90, 120, 150, 180, 210, 240, 270, and 305 days in milk (DIM) to explore the genetic curve patterns of milk production of animals within the population. At first moment, the population was divided into three groups based on animals' genetic curve pattern for milk yield using hierarchical cluster analysis. According to non-hierarchical cluster analysis, one of those groups had EBVs along the lactation curve above the population average. Further cluster analysis done only with those animals with genetic curve pattern above the population mean showed specific subgroups of animals with different genetic curves for milk yield despite of all of those animals had EBVs above the population average, along the lactation curve. It indicated that specific subgroup of animals with a specific genetic curve pattern for milk yield can be chosen depending on the objectives of the breeding program. It was concluded that the cluster analyzes could be used to select animals based on the shapes of the genetic curve for milk production together with the EBV for milk yield at 305 days in milk. Thus, it can be possible to select at the same time more productive animals with genetic curves that met the goals of breeding programs that take into account the milk production in other parts along the milk production curve. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the genetic relationships between first-lactation persistency and four measures of conception accounting for heterogeneous genetic (co)variances over a wide range of milk production and fertility management environments. The combination of genotype and management environment conditions (genotype-by-environment (GE) interaction) was studied by using a reaction norm model. Data were obtained on 421,999 cows from 9296 herds for first parity and 257,815 cows from 8318 herds for second parity. Conception status during the first two parities from calving to 70 days in milk (DIM) and 180 DIM were evaluated, leading to a total of four conception measures. Under poor reproductive management, the genetic correlations between first parity lactation persistency and conception to 70 DIM were 0.408 and 0.242 for the first and second parities, respectively, compared with 0.178 and 0.116 for the respective genetic correlations between lactation persistency and conception to 180 DIM. These positive correlations indicate that increased persistency would help to improve conception to 70 DIM or 180 DIM. The genetic correlation between persistency and conception to 180 DIM during the first parity was −0.211 under a high level of reproductive management and moderately high milk production, suggesting that conception to 180 DIM for low-persistency cows of first parity was increased by improving reproductive management under this situation. In contrast, the genetic correlation between persistency and conception to 180 DIM in second parity was 0.351 under high management of milk production and reproduction. The genetic correlations between lactation persistency and conception to 70 DIM or 180 DIM for the first two parities ranged from negative to positive, depending on the combination of genotype and management environment conditions. Therefore, it is important to consider GE interaction when combining lactation persistency, conception measures, and milk yield to select for sustainable milk production systems. [ABSTRACT FROM AUTHOR]

Red clover is the most important forage legume in the Czech Republic. It is an unassuming species to climatic and soil condition, is suitable for mixtures with grasses and it is above other grassland species in forage quality. The most serious problem of red clover in grasslands is its lack of persistency (2–4 years). Considering of red clover growing area on arable land decrease and area of permanent grasslands increases, becomes persistency of varieties important attribute. The persistency of all Czech varieties was evaluated on the basis of dominance proportion investigation after 3 winters. Assessed varieties were established in mixture with grasses (60:40%). Significantly most persistent varieties were Amos 4n (24.5%), Dolina 4n (20.25 %) and Radegast 4n (19.25%). Varieties of Alsike clover were not significantly different from varieties of red clover.

Winter sea-level pressure fields in the northern hemisphere were analysed with respect to regimes and regime shifts (RS). Classification of the North Atlantic Oscillation (NAO) patterns resulted in the identification of two longer lasting climate regimes: a persistent NAO− period from 1976 to 1988 followed by a persistent NAO+ period from 1989 to 2000. A further persistent NAO− period from 1956 to 1966 cannot be related to climate regime shifts. After 2000, the NAO lost its persistence and the autocorrelation disappeared, while the variance in the benthic data increased. The consequence was a decrease in potential predictability. The impact of the 1988/89 and 2000/2001 RS on the dominant species and taxonomic groups of benthic macrofauna as well as on benthic community structure was evaluated using an AMOEBA model, a quantitative method used in water management to represent the status of the ecosystem. The model confirmed the effects of the smooth RS in 1988/1989 and the abrupt RS in 2000/2001 on the macrofauna communities provided by earlier data analyses.

The extent to which exchange rates of four major currencies against the Greek Drachma exhibit long-term dependence is investigated using a R/S analysis testing framework. We show that both classic R/S analysis and the modified R/S statistic if enhanced by bootstrapping techniques can be proven very reliable tools to this end. Our findings support persistence and long-term dependence with non-periodic cycles for the Deutsche Mark and the French Franc series. In addition a noisy chaos explanation is favored over fractional Brownian motion. On the contrary, the US Dollar and British Pound were found to exhibit a much more random behavior and lack of any long-term structure.

Objectives: Many women are reluctant to undergo estrogen replacement therapy (ERT) and discontinue the treatment within 12 months. The aim of this study was to investigate the persistence rates of ERT in hysterectomized women over the past decade, reflecting changes in the post-Women's Health Initiative (WHI) era.Methods: We analyzed 8045 patients receiving ERT from 2004 to 2013 using the Disease Analyzer database.Results: After 12 months of follow-up, only 24.6% of patients receiving 1 mg and 24.5% of patients receiving 2 mg of oral ERT were still on treatment (p < 0.0001). The persistency rate of patients receiving <50 μg of transdermal ERT was 28.6% compared to 33.5% for patients receiving >50 μg within the 12 months of follow-up. ERT that began in 2007-2009 was associated with a higher discontinuation rate (hazard ratio 1.06, p = 0.0660) than ERT that began in 2010-2013 (hazard ratio 0.88, p = 0.0001).Conclusions: Our results indicate low persistency rates in women on ERT irrespective of the dose as well as the route of administration. However, a decrease in discontinuation rates was found when comparing women in the early vs. late post WHI era. [ABSTRACT FROM AUTHOR]

In the present study, 44,440 test day milk yield records, for first lactation of Iranian Holstein cattle, collected between 1983 and 2010 were used to genetic analysis of the lactation persistency of Iranian Holstein cattle with Legendre Polynomials based Random Regression Models. For analysis, animals with 10 test day records were considered and their breeding values for different measures of persistency and 305-days milk yield (305MY) were estimated by Random Regression analysis. Spearman correlations between breeding values of different persistency measures and 305MY were estimated. The correlations between estimated breeding values for different measures of lactation persistency ranged between 0.32 to 0.99. In addition, the correlation between different persistency measures and 305MY varied from 0.35 to 0.99. In general, results showed that because of positive correlations between some measures of persistency with each other as well as with 305MY, these traits could be used to improve lactation persistency and milk production of Iranian Holstein dairy cows [ABSTRACT FROM AUTHOR]

The objective of this work was to estimate genetic parameters for a measure of persistency of milk yield and to evaluate its association with 305-d cumulative milk yield and lactation length. 12 346 records from 8202 dairy Gyr cows including lactations up to fifth calving were used. The measure of persistency was obtained from one of the parameters of a quadratic model that describes the cumulative yield across lactation as a function of days in milk. A three-trait multivariate analysis was done. Heritability and repeatability for persistency were 0·08 and 0·21, respectively. Deviance Information Criterion provided evidence that the additive genetic covariance between the measure of persistency studied and 305-d cumulative yield is zero. Genetic correlations between persistency and lactation length were 0·50 and 0·27 for first or all lactations, respectively. Milk yield persistency as measured in this study has low heritability. Selection for persistency can increase lactation length. The measure of milk yield persistency studied here is genetically independent of total milk yield and can be included in routine genetic evaluations of dairy cattle. [ABSTRACT FROM PUBLISHER]

Objectives: Many women are reluctant to take menopausal hormone therapy (MHT) and discontinue the treatment within 12 months. The aim of this study was to investigate the persistence rates of combined MHT in the last decade, reflecting changes in the post-Women's Health Initiative era.Methods: We analyzed 17 020 patients receiving combined MHT from 2004 to 2013 using the Disease Analyzer database.Results: After 12 months of follow-up, 44.6% and 33.5% of patients receiving 1 mg and 2 mg, respectively, of oral combined MHT were still on treatment (p < 0.0001). The persistence rate of patients receiving < 50 μg of transdermal MHT was 39.1% after 1 year of treatment and presented no differences compared to patients receiving ≥ 50 μg of transdermal MHT with a persistence rate of 38.2%. MHT start in the years 2007-2009 was associated with higher discontinuation rates (hazard ratio 1.04, p = 0.0709) than MHT start in the years 2010-2013 (hazard ratio 0.90, p = 0.0001).Conclusions: Our results indicate that patients beginning their treatments in the years 2010-2013 were more treatment-persistent than patients beginning with MHT in the early years after publication of the Women's Health Initiative study (2004-2009). Administration of low-dose oral MHT and transdermal MHT is associated with increased persistency compared to higher doses of oral MHT. [ABSTRACT FROM AUTHOR]

The article presents a study that deermines the average daily milk production, yield, and prediction models in Indian dromedary.

The aim of this study was to identify the risk factors for persistence of coronary artery abnormalities (CAAs) in Kawasaki disease and to compare the differences between complete (n=25) and incomplete (n=18) forms of the disease in relation to CAAs. The patients' demographic (age and sex), clinical (season of admission, duration of fever, form of Kawasaki disease), laboratory (complete blood count, eosinophil count, serum biochemistry, C-reactive protein level, erythrocyte sedimentation rate [ESR], urinary analysis), echocardiographic and therapeutic data were evaluated retrospectively from the medical records. The incidence of sterile pyuria was nearly twofold greater in patients with initial CAAs than in patients in which CAAs were not present (25% and 13%, respectively; p=0.33). In multivariate logistic regression analysis, ESR and pyuria were found to be associated with persistence of CAAs (p=0.035 and p=0.046, respectively). In addition, we found that duration of fever was significantly associated with persistence of CAAs (p=0.045). However, gender, age at presentation, peripheral blood eosinophilia, low albumin level, CRP, leukocytosis and anemia were not predictive for persistence of CAAs. There was no difference between the complete and incomplete form of the disease in regard to persistence of CAAs. As a result, we have determined that duration of fever, high levels of ESR and presence of sterile pyuria can be used to predict the persistence of CAAs in Kawasaki disease. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the lactation curve traits of Anatolian buffaloes raised under different conditions in farms in Tokat Province, Turkey. Wood's gamma curve parameters were employed to identify the lactation curve types, and values for the parameters beginning yield (a), coefficient of rising (b) and coefficient of decreasing (c) were used to determine the shape and type of lactation curve. All parameters in typical lactation curves were positive, and in the event of one parameter being negative, the curve was considered to be an atypical lactation curve. A total of 690 lactation curves were investigated. It was determined that 406 (58.84%) of these curves were typical, while 90 (13.04%) were concave and 194 (28.12%) of a decreasing type. For typical lactation curves, a, b, c, persistency (S), time after parturition until the peak yield occurs (Tmax), maximum daily peak yield (Ymax), and coefficient of determination (R²) were 7.14±0.008, 0.85±2.1, 0.40±0.001, 2.68, 63.6, 6.41 and 76.33, respectively. For concave lactation curves, values for a, b, c, Tmax, Ymax and R² were 4.94±0.42, -0.73±0.016, - 0.23±0.0038, 95.40, 7.41±0.004 and 71.68, respectively. For decreasing typical lactation curves, values for a, b, c, Tmax, and R² were 5.31±0.0041, -0.15±0.007, 0.039±0.0023, 3.89±0.11 and 79.94, respectively. Parameters predicted by the Wood model within the scope of this study have the potential of being useful for breeding programmes. Further breeding/selection activities could be conducted by using the female Anatolian buffaloes with typical lactation curves. [ABSTRACT FROM AUTHOR]

Health disorders in dairy cows have a substantial effect on the profitability of a dairy enterprise because of loss in milk sales, culling of unhealthy cows, and replacement costs. Complex relationships exist between health disorders and production traits. Understanding the causal structures among these traits may help us disentangle these complex relationships. The principal objective of this study was to use producer-recorded data to explore phenotypic and genetic relationships among reproductive and metabolic health disorders and production traits in first-lactation US Holsteins. A total of 77,004 first-lactation daughters' records of 2,183 sires were analyzed using recursive models. Health data contained information on reproductive health disorders [retained placenta (RP); metritis (METR)] and metabolic health disorders [ketosis (KETO); displaced abomasum (DA)]. Production traits included mean milk yield (MY) from early lactation (mean MY from 6 to 60 d in milk and from 61 to 120 d in milk), peak milk yield (PMY), day in milk of peak milk yield (PeakD), and lactation persistency (LP). Three different sets of traits were analyzed in which recursive effects from each health disorder on culling, recursive effects of one health disorder on another health disorder and on MY, and recursive effects of each health disorder on production traits, including PeakD, PMY, and LP, were assumed. Different recursive Gaussian-threshold and threshold models were implemented in a Bayesian framework. Estimates of the structural coefficients obtained between health disorders and culling were positive; on the liability scale, the structural coefficients ranged from 0.929 to 1.590, confirming that the presence of a health disorder increased culling. Positive recursive effects of RP to METR (0.117) and of KETO to DA (0.122) were estimated, whereas recursive effects from health disorders to production traits were negligible in all cases. Heritability estimates of health disorders ranged from 0.023 to 0.114, in accordance with previous studies. Similarly, genetic correlations obtained between health disorders were moderate. The results obtained suggest that reproductive and metabolic health disorder and culling due to metabolic and reproductive diseases have strong causal relationships. Based on these results, we concluded that a health disorder (either reproductive or metabolic) occurring in early lactation has a moderate causal effect on the reproductive or metabolic health disorder occurring in later lactation. In addition, direct, indirect, and overall effects of reproductive and metabolic health disorders on milk yields for cows that avoid culling are weak. [ABSTRACT FROM AUTHOR]

Milk production in the intertropical region has been based on the crossbreeding of Bos taurus taurus with Bos taurus indicus breeds, generating products of high hybrid vigor as the F1 mix breed with high productive-reproductive potential and resistance to the environment. The dairy productive performance and the reproductive performance of F1 Holstein x Brahman cows in a herd raised in warm climate in the municipality of Cartago, Valle del Cauca, Colombia were evaluated. Records for age at first calving (AFC, n=23), Calving Interval (CI, n=60), milk production per lactation (n=71) and lactation persistency (LP, n=67) in crossbreeding of Holstein bull with Brahman cows were evaluated; the cows were milked twice a day with calf support and supplementation per milking lot. The AFC was 31.3±4.12 months; the average of CI was 423.46±111.26 days; milk production average per lactation was 3052±785 kg, with a range between 540 and 3471 kg. The average LP was 54.22±17.59%, with persistency higher than 60% until the third lactation and lower than 40% after the seventh lactation. In conclusion the productive and reproductive performance in F1 Holstein x Brahman cows is optimum and superior compared to the Colombian double purpose cattle national parameters. F1 Holstein x Brahman cows are long lived reaching ages of 139 months (11.5 years) with eight (8) lactations, milk production per lactation higher than 3000 kg and persistency close to 40%. Nevertheless, this genetic potential is only shown under good nutritional management. [ABSTRACT FROM AUTHOR]

Este experimento foi conduzido na Embrapa-Centro Nacional de Pesquisa de Gado de Leite, situada em Coronel Pacheco, MG, de outubro de 1995 a outubro de 1997, para avaliar o efeito de cinco doses de nitrogênio (zero, 100, 200, 400 e 600 kg/ha/ano) e três intervalos de cortes (2, 4 e 6 semanas, nas chuvas, e 4, 6 e 8 semanas, na seca) na produção de matéria seca e teor de proteína bruta do capim tifton 85. O delineamento experimental adotado foi em blocos ao acaso, em parcelas divididas e três repetições. Nas parcelas foram alocados os intervalos de cortes, e nas subparcelas, as doses de nitrogênio. A produção anual de matéria seca do tifton 85 cresceu com a dose de nitrogênio até a aplicação de 600 kg/ha/ano, e até o intervalo de cortes de quatro semanas, nas chuvas, e seis semanas, na seca. A maior produção de matéria seca foi de 23,1 t/ha/ano, com 17,8 t/ha obtidas na época das chuvas. A menor produção foi de 2,6 t/ha/ano, sendo 1,9 t/ha alcançada nas chuvas. O teor de proteína bruta aumentou com a elevação da dose de nitrogênio até 600 kg/ha/ano, tanto nas chuvas quanto na seca, e com a redução do intervalo de cortes, na seca. Nas chuvas, não houve efeito do intervalo de cortes sobre o teor de proteína bruta. O teor máximo de proteína bruta obtido foi de 21,7%. A persistência do tifton 85 foi comprometida pela ausência da adubação nitrogenada e pelo menor intervalo de cortes.This experiment was carried out at Embrapa-Centro Nacional de Pesquisa de Gado de Leite, located in Juiz de Fora, MG, Brazil, from October, 1995 to October, 1997, to evaluate the effects of five N doses (0, 100, 200, 400 and 600 kg/ha/year) and three cutting intervals (two, four and six weeks, during the rainy season, and four, six and eight weeks, during the dry season) on dry matter production and crude protein content of tifton 85. Data were analyzed as randomized blocks design in split-plot, with three replicates. The annual dry matter yield increased up to the highest dose of 600 kg/ha/year of N fertilization and up to four weeks cutting interval, during rainy season, and six-week cutting intervals, during the dry season. The highest production of dry matter was 23.1 ton/ha/year, of which 17.8 ton/ha were obtained in the rainy season. The lowest production was 2.6 ton/ha/year, of which 1.9 ton/ha were obtained in the rainy season. Crude protein content varied inversely with cutting intervals and as the amount of N fertilization increased up to dose of 600 kg/ha/year. The crude protein contents did not differ significantly with cutting intervals during the raining season. The highest level of crude protein obtained was 21.7%. Tifton 85 persistency was hampered in the absence of N fertilization and the shortest cutting interval.

No presente estudo foi estimada a curva de lactação média de 7239 lactações de vacas da raça Caracu, com base em 299.949 controles semanais. As funções ajustadas aos dados médios da curva de lactação foram Linear Hiperbólica e Quadrática Logarítmica, como lineares, e Gama Incompleta e Polinomial Inversa, como não-lineares. Os parâmetros foram estimados por meio de processos iterativos, método de Gauss-Newton. O Coeficiente de Determinação ajustado (R²A), o Teste de Durbin-Watson (DW) e os desvios (%) entre as produções totais (PTL) observadas e estimadas foram usados como medida da qualidade do ajuste. Os resíduos estimados, apesar de pequenos, apresentaram correlação serial positiva, pois o teste DW foi significativo para as quatro funções estudadas, indicando violação da pressuposição de independência entre estes resíduos. Os R²A foram superiores a 97% e os desvios entre as PTL observadas e estimadas, mínimos, indicando que, de acordo com estes critérios, qualquer função poderia ser usada para ajustar a curva de lactação média desse rebanho. Quanto aos componentes da curva, a melhor aproximação foi obtida pela função Polinomial Inversa, para produção inicial, tempo e produção no pico. As funções Gama Incompleta e Quadrática Logarítmica apresentaram ajustes semelhantes, porém a primeira apresentou melhor definição dos parâmetros e componentes da curva de lactação.The present study was carried out to estimate the average lactation curve of 7239 lactations of Caracu cows based on 299,949 weekly records. The functions fitted to the mean data of the lactation curve were: Linear Hyperbolic and Logarithmic Quadratic as linear and Incomplete Gamma and Inverse Polynomial function as non-linear. The parameters were estimated by iterative methods, Gauss-Newton method. The adjusted Coefficient of Determination (R²A), the Durbin-Watson test (DW) and the deviations (%) from actual and predicted total milk yield were used as measurement of goodness of fit. The estimated residues, even though small, presented a positive serially correlation because the DW test was significant for the four studied functions, indicating violation of the assumption of the independence among the residues. The R²A were higher than 97%, and the deviations between actual and predicted milk yields were small, indicating that, in accordance with this criterion, any function could be used to fit the average lactation curve of the herd. Regarding to the components of the lactation curve the best approach was obtained by the Inverse Polynomial function for initial production, time and production on peak. The Incomplete Gamma and Logarithmic Quadratic functions presented similar adjustment, however, the first one presented better definition of parameters and components of the lactation curve.

Genetic selection programs have driven development of most lactation models, to estimate the magnitude of animals’ productive capacity from sampled milk production data. There has been less attention to management and research applications, where it may also be important to quantify the shape of lactation curves, and predict future daily milk production for incomplete lactations since residuals between predicted and actual daily production can be used to quantify the response to an intervention. A model may decrease the confounding effects of lactation stage, parity, breed, and possibly other factors depending on how the model is constructed and used, thus increasing the power of statistical analyses. Models with a mechanistic derivation may allow direct inference about biology from fitted production data. The MilkBot® lactation model is derived from abstract suppositions about growth of udder capacity. This permits inference about shape of the lactation curve directly from parameter values, but not direct conclusions about physiology. Individual parameters relate to the overall scale of the lactation, the ramp, or rate of growth around parturition, decay describing the senescence of productive capacity (inversely related to persistence), and the relatively insignificant time offset between calving and the physiological start of milk secretion. A proprietary algorithm was used to fit monthly test data from two parity groups in 21 randomly selected herds, and results displayed in box-and-whisker charts and Z-test tables. Fitted curves are constrained by the MilkBot® equation to a single peak that blends into an exponential decline in late lactation. This is seen as an abstraction of productive capacity, with actual daily production higher or lower due to random error plus short-term environmental effects. The four MilkBot® parameters, and metrics calculated directly from them including fitting error, peak milk and cumulative production, can be used to describe and compare individual lactations or groups of lactations. There is considerable intra-herd and inter-herd variability in scale, ramp, decay, RMSE, peak milk, and cumulative production, suggesting that management and environment have significant influence on both shape and magnitude of normal lactation curves.

Aims/Introduction Previous research showed the association between health-related quality of life and metabolic syndrome (MetS). The present study aimed to examine the impact of persistence of MetS on health-related quality of life in non-diabetic Iranian adults. Materials and Methods This was a cross-sectional study. A representative sample of 643 non-diabetic individuals (67% female), aged ≥20 years, who participated in the Tehran Lipid and Glucose Study in 2005-2007 were recruited for the study, and categorized into four groups, those without, with transient, with intermittent and with persistent MetS. Health-related quality of life was assessed using the Iranian version of the Short Form Health Survey. MetS was diagnosed using the Joint Interim Statement criteria. Results Women with transient, intermittent and persistent MetS scored lower on the Physical Component Summary than those without the syndrome (51.03 ± 1.41, 48.16 ± 1.46 and 46.58 ± 1.29 vs 52.18 ± 1.20) after adjusting for potential confounders ( P = 0.04). In women, there was also a significant decreasing trend in the scores of bodily pain ( P for trend = 0.006) and general health ( P for trend = 0.005) across the study groups. Compared with women without MetS, the odds ratio of reporting poor health-related quality of life for women with intermittent MetS was 2.75 (95% confidence interval 1.19-6.37, P = 0.01). Among men, however, no significant difference was observed in any of the health-related quality of life domains. Conclusions Compared with women without, with transient and with persistent MetS, those with intermittent MetS reported poorer physical health-related quality of life. [ABSTRACT FROM AUTHOR]

In tropical environments, lactation curves with lower peaks and higher persistency (PS) might be desirable from both an economical and a physiological point of view. The objective of this study was to obtain genetic parameters for test day (TD) yields, and PS for the tropical breed Carora and to compare these with results from a standard 305-d-milk yield animal model. Four random regression models (RRM) were used on a dataset composed of 95,606 TD records collected in Venezuela and tested to find the best fitting the data. Estimated daily heritabilities for milk yields ranged from 0.21 to 0.30, with the lowest values around the peak of lactation. Lactation repeatabilities ranged from 0.50 to 0.56. Correlations between the breeding values obtained with the RRM and the lactation model currently used in Venezuela [single trait Animal Model (stAM)] are quite high and positive (Pearson correlation=0.71 and Spearman correlation=0.72). Correlations between PS and 305-d-milk yield estimated breeding values (EBV) ranged from -0.18 (PS as the deviation of daily productions in the interval 50-279 days in milk from a point at the end of lactation) to 0.52 (PS as EBV difference between the second and the first stage of lactation). The use of PS indexes accounting for milk yield may allow the selection of individuals able to express their potential genetic values in tropical environment, without incurring in excessive heat stress losses [ABSTRACT FROM AUTHOR]

A study was made using 6 140 milk yield records on the test day, from ten fortnightly milk test recordings of 631 lactations corresponding to 383 Anglo Nubia x Criolla goats located in six herds in Loja, Ecuador, during the period from 2011 to 2013. The purpose was to determine the non-genetic factors affecting lactation persistency and to estimate their correlation with total milk yield, milk yield adjusted to 152 d and lactation length. A linear, mixed generalized model was applied through the GLIMMIX procedure of SAS. As fixed effect were considered the herd, kidding year, season, number of lactation and youngs. Lactation length was considered as linear covariable and the random effect was associated with each goat dwelling in the herd. For estimating Pearson's correlations, the CORR procedure of SAS was applied. Persistency was of 69.4 %. The non-genetic factors were significant, except for litter size. The phenotypic correlations of total milk persistency, adjusted milk and lactation length were 0.20, 0.16 and 0.14, respectively. It is concluded that lactation persistency had a low phenotypic correlation regarding milk yield and lactation length. Further investigations should be conducted with greater number of samples and genealogical information for recommending its inclusion in genetic breeding programs. [ABSTRACT FROM AUTHOR]

Rainfalls with short persistency are the tangible characteristics of arid and semiarid regions such as Iran. Iran is an arid and semiarid region with dramatic tempo-spatial changes of rainfall. In this regard, the short persistency of rainfall is approximately observed from 1 to 7 days in whole parts, while the greater ones are only separated in eastern parts of Iran. According to the results, the rainfall persistency is ranged from 1 to 45 days, but the maximum amount and rainy days are generated by rainfalls with short persistency. So, the rainfall events with long persistency are considered as an extreme event with extreme variability. One-day precipitations generate the maximum rainy days and rainfall amounts, especially in eastern parts of Iran. Decrease in the one-day precipitations contribution to eastern parts may indicate to decrease in regional precipitation. However, decrease in contribution in western parts may indicate to increased amounts of rainfall at other persistency rates. Our results revealed that the contribution of the one-day precipitation to general rainfall has reductive trends in almost 17.5 % of the whole Iran. The most integrated and significant reductive trend of one-day precipitation contribution to rainfall spreads northeastern and eastern parts of Iran. However, in the western parts of Iran, decreasing one-day precipitation contribution to rainy days affects to increase in the diurnal rainfall. The mentioned variability can be considered as the climate change signals in respect of one-day precipitation. [ABSTRACT FROM AUTHOR]

Milk production from dairy animals has been described in terms of 3 processes: the increase in secretory cell numbers in late pregnancy and early lactation, secretion rate of milk per cell, and the decline in cell numbers as lactation progresses. This latter process is thought to be determined by the level of programmed cell death (apoptosis) found in the animal. Until now, apoptosis has been measured by taking udder biopsies, using magnetic resonance imaging scans, or using animals postmortem. This paper describes an alternative, noninvasive method for estimating apoptosis by measuring microparticles in milk samples. Microparticles are the product of several processes in dairy animals, including apoptosis. Milk samples from 12 Holstein cows, at or past peak lactation, were collected at 5 monthly samplings. The samples (n = 57) were used to measure the number of microparticles and calculate microparticle density for 4 metrics: annexin V positive and merocyanine 540 dye positive, for both and total particles, in both whole milk (WM) and spun milk. Various measures of milk production were also recorded for the 12 cows, including daily milk yield, fat and protein percentage in the milk, somatic cell count, and the days in milk when the samples were taken. A high correlation was found between the 4 WM microparticle densities and days in milk (0.46 to 0.64), and a moderate correlation between WM microparticle densities and daily milk yield (-0.33 to -0.44). No significant relationships were found involving spun milk samples, somatic cell count, or fat and protein percentage. General linear model analyses revealed differences between cows for both level of microparticle density and its rate of change in late lactation. Persistency of lactation was also found to be correlated with the WM microparticle traits (-0.65 to -0.32). As apoptosis is likely to be the major contributor to microparticle numbers in late lactation, this work found a noninvasive method for estimating apoptosis that gave promising results. Further investigation is required to find out the factors affecting microparticle production and how it changes throughout lactation. [ABSTRACT FROM AUTHOR]

The earth's ionosphere is well recognized as a dynamical system and non-linearly coupled with the magnetosphere above and natural atmosphere below. The shape and time variability of the ionosphere indeed shows chaos, pattern formation, random behaviour and self-organization. The present paper studies the propriety of Multifractal Detrended Fluctuation Analysis (MF-DFA) technique for the ionospheric scintillation index time series. MF-DFA is used to identify the scaling behaviour of the ionospheric scintillation time-series data of two different nature. The obtained results show the robustness and the relevancy of the MF-DFA technique for the ionospheric scintillation index time series. The comparison of the MF-DFA results of original data to those of shuffled and surrogate series shows that the multifractal nature of considered time-series is almost due to long-range correlations. Subsequently, the Hurst exponents derived from two parallel methods namely Rescaled range analysis (R/S) and Auto Correlation Function (ACF) are also suggesting the presence of long range correlation. The presented results in this work may be of assistance for future modeling and simulation studies. [ABSTRACT FROM AUTHOR]

Aims To establish the 3-year persistency rate of alcohol use disorder ( AUD) and its predictors, and to examine drinking patterns of recently remitted individuals. Design and Setting The Netherlands Mental Health Survey and Incidence Study-2 ( NEMESIS-2) surveyed a nationally representative sample of adults (aged 18-64 years) at baseline (response = 65.1%) and 3-year follow-up (response = 80.4%). Participants People with AUD at baseline, as defined by DSM-5 ( n = 198). Measurements AUD, drinking patterns and mental disorders were assessed using the Composite International Diagnostic Interview 3.0. Other predictors were assessed with an additional questionnaire. Predictors of persistency were examined with univariable and multivariable logistic regression analyses. Results The AUD persistency rate was 29.5% [95% confidence intervals ( CI) = 20.0-39.0]. In the multivariable model, the older (25-34 and 35-44) age groups had lower AUD persistency [odds ratio ( OR) = 0.05; 95% CI = 0.00-0.49 and OR = 0.14; 95% CI = 0.02-0.79, respectively] than the youngest age group (18-24). A higher number of weekly drinks and a comorbid anxiety disorder predicted AUD persistency ( OR = 1.03; 95% CI = 1.00-1.07 and OR = 4.56; 95% CI = 1.04-20.06, respectively). Furthermore, remission was associated with a reduction of six drinks per week between T0 and T1. It should be noted, however, that 35.8% (95% CI = 22.4-49.2) of people in diagnostic remission still drank more than the recommended maximum (more than seven/14 drinks weekly for women/men). Conclusions Only a minority of people in the Netherlands with alcohol use disorder as defined by DSM-5 still have the disorder 3 years later. Factors that help to identify people at risk of alcohol use disorder persistence are: younger age, a higher number of weekly drinks and a comorbid anxiety disorder. A substantial number of people recently in diagnostic remission still drink above the maximum recommended level. [ABSTRACT FROM AUTHOR]

Abstract: A total of 104,135 test-day records from 13,314 first lactations of dairy Gyr×Holstein cows were used. Test-day yields of milk, fat and protein were analyzed using a three-trait random regression model. Heritabilities for daily milk, fat and protein yield ranged from 0.12 to 0.24, 0.13 to 0.21 and 0.12 to 0.26, respectively. For daily yields, the additive genetic correlations ranged from 0.38 to 0.99 (milk), 0.25 to 0.99 (fat) and 0.22 to 0.99 (protein) and were higher among adjacent test days, decreasing gradually with increasing distance between days of lactation. The additive genetic correlations between the traits at different stages of lactation were high (always >0.70). The heritabilities for cumulative yield and persistency were 0.21 and 0.14 (milk), 0.24 and 0.16 (fat) and 0.20 and 0.18 (protein), respectively. The additive genetic correlations for cumulative yield were 0.96 (milk–fat), 0.93 (milk–protein) and 0.90 (fat–protein), and those for persistency were 0.73 (milk–fat), 0.85 (milk–protein) and 0.87 (fat–protein). The correlations between cumulative yield and persistency were negative, but low, for the three traits studied. The random regression model proposed in this study can be applied to the genetic evaluation of dairy Gyr (Bos indicus) cattle using test-day yields rather than the traditional estimates of cumulative yield. [Copyright &y& Elsevier]

The objectives of the present study were to estimate genetic parameters of monthly test-day milk yield (TDMY) of the first lactation of Brazilian Holstein cows using random regression (RR), and to compare the genetic gains for milk production and persistency, derived from RR models, using eigenvector indices and selection indices that did not consider eigenvectors. The data set contained monthly TDMY of 3,543 first lactations of Brazilian Holstein cows calving between 1994 and 2011. The RR model included the fixed effect of the contemporary group (herd-month-year of test days), the covariate calving age (linear and quadratic effects), and a fourth-order regression on Legendre orthogonal polynomials of days in milk (DIM) to model the population-based mean curve. Additive genetic and nongenetic animal effects were fit as RR with 4 classes of residual variance random effect. Eigenvector indices based on the additive genetic RR covariance matrix were used to evaluate the genetic gains of milk yield and persistency compared with the traditional selection index (selection index based on breeding values of milk yield until 305 DIM). The heritability estimates for monthly TDMY ranged from 0.12 ± 0.04 to 0.31 ± 0.04. The estimates of additive genetic and nongenetic animal effects correlation were close to 1 at adjacent monthly TDMY, with a tendency to diminish as the time between DIM classes increased. The first eigenvector was related to the increase of the genetic response of the milk yield and the second eigenvector was related to the increase of the genetic gains of the persistency but it contributed to decrease the genetic gains for total milk yield. Therefore, using this eigenvector to improve persistency will not contribute to change the shape of genetic curve pattern. If the breeding goal is to improve milk production and persistency, complete sequential eigenvector indices (selection indices composite with all eigenvectors) could be used with higher economic values for persistency. However, if the breeding goal is to improve only milk yield, the traditional selection index is indicated. [ABSTRACT FROM AUTHOR]

The article discusses the study that evaluates the characteristics of genetic parameters of milk yield and persistency at different milking times in primiparous Holstein dairy cows in Iran, that found high residual variance at the start of lactation and gradual decrease until the end of lactation. The study revealed increase in additive genetic variance till the end of lactation, particularly in morning milk, and moderate increase in permanent environmental variance.

Abstract: This study investigates the degree of persistence in monthly Brent crude oil spot and futures prices (at one, two and three months to maturity). The main finding from the full sample shows that Brent crude oil spot, one, two and three months to maturity futures prices are characterized by a high degree of persistence without structural breaks. However, these prices are not highly persistent when structural breaks are taken into consideration. The analysis is repeated for four sub-periods delineated by the endogenously determined break points. The results obtained from the sub-period analysis indicate that oil price series are typically very persistent which is consistent with the efficient market hypothesis. [Copyright &y& Elsevier]