Relative variability of phenotypic traits and indicators of milk productivity of cows

The research was conducted on cattle of Black-and-White breed (Holstein and Ukrainian Black-and-White dairy breed) at LLC “Veleten” Glukhiv district of Sumy region (n = 1956) and PJSC “Breeding Plant “Stepnoy” of Kamyansko-Dniprovsk district of Zaporizhzhia region (n = 1981). Based on retrospective data analysis (“Uniform-Agri” – program of dairy herd management) for the period from 2004 to 2017 it was studied the live weight of cows in growing period (newborns, 6, 12; 18 months, at first insemination and after the first calving), body measurements of heifers (height at shoulders, chest depth, chest width, chest girth behind the shoulder blades, oblique body length, width of hips, wrist girth) and traits of reproducibility (age at first insemination, age at first calving, duration of service period, insemination index, fertility index) and milk productivity of cows (milk yields for 305 days, fat and protein content in milk for the first, second and third lactation). Based on our previously obtained data by correlation analysis method it was studied the relative variability of phenotypic traits and indicators of dairy productivity of cows. It is established that the connections of live weight of cows during their rearing with traits of milk productivity were multidirectional and ranged from slightly improbable to moderately significant values. At the same time, in both farms, the most significant highly probable connection was noted between the live weight of animals at the age of 12 months and the milk yield of first-borns that indicates the possibility of selecting heifers at the specified age to provide them future high milk productivity. There was significant variability of the relationship between body measurements and the amount of milk yield of cows for the first, second and third lactation. However, cows of both farms, had direct connection, but a bit weaker in animals at PJSC “Breeding Plant “Stepnoy”. Positive correlation coefficients between indicators of exterior and milk yields of cows give reasons to claim the efficiency of indirect selection of heifers by body measurements. Rational management of dairy farming and high profits depend a lot on knowledge of regularities of correlative variability of productive traits of cows and indicators of reproductive capacity. It is established that the connections between the traits of milk productivity and reproductive capacity of animals were different and ranged from weak to medium and from reliable to improbable. The most significant highly reliable, however, with negative correlation coefficients were observed between milk yield of cows for all studied lactations and their age at the first insemination and the first calving

CD-1 Outbred Mice Produce Less Variable Ultrasonic Vocalizations Than FVB Inbred Mice, While Displaying a Similar Developmental Trajectory

The production of ultrasonic vocalizations (USVs) in neonatal mice is a critical means of communication that is used to elicit maternal care. Alterations in neonatal USV production is also an indicator of neurological deficits. However, USVs have been predominately assessed in inbred animals and are significantly understudied in outbred mice, even though outbred animals better represent the genetic diversity of humans and are used in several neurological disorder models. To determine the reproducibility of USVs across models, we compared male and female CD-1 (outbred) and FVB (inbred) mice on postnatal days (PD) 4, 8, 12, 16, and 20. We found that CD-1 and FVB mice displayed a similar developmental trajectory of USVs. However, CD1 mice emitted more USVs on PD 12 than FVB mice. In addition, FVB mice emitted a longer duration of calls on PD 4 and 8 and a higher overall maximum and minimum frequency of USVs than CD-1 mice. No differences in mean amplitude were found between groups. We also detected numerous significant differences between outbred and inbred mice when comparing each group's call composition. We next assessed the relative variability of mouse vocalizations between groups, finding that outbred mice were less variable than inbred mice. For the spectral and temporal characteristics of the USVs, variability was similar between groups. Altogether, we found that CD-1 outbred mice display a similar, if not lower, degree of variability than FVB inbred mice when assessing neonatal USVs.

Modelling Feedback Effects on the Production of Short Time Intervals

People produced time intervals of 500 to 1250 ms, with accurate feedback in ms provided after each production. The mean times produced tracked the target times closely, and the coefficient of variation (standard deviation/mean) declined with increasing target time. The mean absolute change from one trial to another, and its standard deviation, measures of trial-by-trial change, also increased with target time. A model of feedback was fitted to all four measures. It assumed that the time produced resulted from a combination of a scalar timing process and a non-timing process. Although the non-timing process was on average invariant with target time, the timing process was assumed to be sensitive to feedback, in two different ways. If the previous production was close to the target the model repeated it (a repeat process), but if it was further away the next production was adjusted by an amount related to the discrepancy between the previous production and the target (an adjust process). The balance between the two was governed by a threshold, which was on average constant, and it was further assumed that the relative variability of the repeat process was lower than that of the adjust process. The model produced output which fitted three of the four measures well (average deviation of 3 or 4%) but fitted the standard deviation of change less well. Reducing the magnitude of the non-timing process produced output which conformed approximately to scalar timing, and the model could also mimic data resulting from the provision of inaccurate feedback.

Relative Variability in Signs of Reproductive Fitness of Pigs

Studies of relative variability make it possible to forecast the future. The equations of rectilinear and multiple regression make it possible to determine a productive indicator by indirectly evaluating correlatively related features. We developed mathematical modelson the relative variability in the signs of reproductive fitness of pigs in the breeding factories of the North Caucasus: “Ventsy-Zarya”, “Gulkevichsky”, “Kavkaz” and “Zarya” of the Krasnodar Territory, “Rossiya” of the Stavropol Territory, and “Rossiya” of the Rostov region. We analyzed the correlations of reproductive fitness in these breeding farms to determine a reliable and objective assessment of cause-and-effectdependencies, and the values, nature and direction of their action. Significant differences were established between the nature of relations in various breeding farms; however, their action vectorscoincided. The models we developed take into account all of the processes occurring in the population under the influence of tribal selectionand can be used in the planning of breeding measures. Keywords: pig breeding, relative variability, correlation, regression, breeding index

Bayesian Bandwidths in Semiparametric Modelling for Nonnegative Orthant Data with Diagnostics

Multivariate nonnegative orthant data are real vectors bounded to the left by the null vector, and they can be continuous, discrete or mixed. We first review the recent relative variability indexes for multivariate nonnegative continuous and count distributions. As a prelude, the classification of two comparable distributions having the same mean vector is done through under-, equi- and over-variability with respect to the reference distribution. Multivariate associated kernel estimators are then reviewed with new proposals that can accommodate any nonnegative orthant dataset. We focus on bandwidth matrix selections by adaptive and local Bayesian methods for semicontinuous and counting supports, respectively. We finally introduce a flexible semiparametric approach for estimating all these distributions on nonnegative supports. The corresponding estimator is directed by a given parametric part, and a nonparametric part which is a weight function to be estimated through multivariate associated kernels. A diagnostic model is also discussed to make an appropriate choice between the parametric, semiparametric and nonparametric approaches. The retention of pure nonparametric means the inconvenience of parametric part used in the modelization. Multivariate real data examples in semicontinuous setup as reliability are gradually considered to illustrate the proposed approach. Concluding remarks are made for extension to other multiple functions.

Heterogeneity and efficacy of antipsychotic treatment for schizophrenia with or without treatment resistance: a meta-analysis

Two important clinical questions are whether there is a subtype of schizophrenia which responds differently to clozapine relative to other antipsychotics, and whether greater efficacy of clozapine is dependent on the degree of treatment-resistance. The authors address this by examining both variability and magnitude of response in patients treated with clozapine and other antipsychotics for both treatment-resistant schizophrenia (TRS) and non-resistant schizophrenia. Double-blind randomised controlled trials comparing clozapine with other antipsychotics in patients with schizophrenia were identified using five databases. Standard deviations and means of change in total, positive, and negative symptoms were extracted. Variability ratio (VR) and coefficient of variation ratio (CVR) were used to quantify relative variability in symptom change. Hedges’ g was used to quantify mean differences. Ten TRS studies (n = 822) and 29 non-TRS studies (n = 2566) were meta-analysed. Relative variability in change of total symptoms did not differ significantly between clozapine and other antipsychotics in TRS studies (VR = 1.84; 95%CI, 0.85–4.02). These findings were similar with CVR, and for positive and negative symptoms. Clozapine was superior to other antipsychotics in improving total symptoms in both TRS (g = 0.34; 95%CI, 0.13–0.56) and non-TRS (g = 0.20; 95%CI, 0.08–0.32) studies. Furthermore, clozapine was superior in improving positive symptoms in both study groups, but not for negative symptoms. Pooled effect sizes showed no significant difference between TRS and non-TRS studies. These findings do not support a subtype of schizophrenia which responds specifically to clozapine. Clozapine is more effective than other antipsychotics irrespective of treatment-resistance, arguing for its use more generally in schizophrenia. PROSPERO CRD42018086507