Morphological Description and Live Weight Prediction from Body Measurements of Socorro Island Merino Lambs.

The aim of this study was to describe the morphology and estimate live weight from body measurements of Socorro Island Merino lambs. A group of Socorro Island Merino lambs was recorded from birth to year for live weight, rump width, rump length, withers height, body length, cannon bone perimeter, and chest girth, width, and depth. The effect of the lamb type on body measurements and live weight was analyzed using ANOVA, Pearson's correlation analysis was performed to estimate the relationship between body measurements and live weight, multiple linear regressions were fitted to obtain prediction equations of live weight from the body measurements and finally, chest girth was used to generate prediction equations using linear and exponential models. At birth and at year, differences were observed in body measurements, especially those related to the thoracic region, with crossbred males showing the highest values. Live weight was correlated with almost all the body measurements, with the highest coefficients observed with chest girth, chest width, and chest depth. Live weight can be accurately predicted from multiple regression equations using several body measurements, but using only chest girth (CG) as a predictor, the exponential equation W0-365 = 0.9142 exp(0.0462 CG) showed the best accuracy.

Determination of the Optimal In-Feed Amino Acid Ratio for Japanese Quail Breeders Based on Utilization Efficiency.

The description of the genetic potential is the first step to estimating amino acid requirements and the ideal amino acid relation (IAAR). The aim of this study was to estimate the parameters that describe the daily maximum theoretical nitrogen retention (NRmaxT, mg/BWkg0.67), daily nitrogen maintenance requirement (NMR, mg/BWkg0.67), protein quality (b), dietary efficiency of the limiting amino acid (bc-1) and determine the lysine requirement and the IAAR for Japanese quail breeders. Two nitrogen balance assays were performed, one assay using 49 quails distributed in seven treatments (protein levels between 70.1 and 350.3 g/kg) and seven replicates and other assay to determine the IAAR by the use of bc-1, 12 treatments and 10 replicate, with a control diet (CD) and 11 treatments that had limited essential amino acids by providing only 60% of the CD. The values obtained for NRmaxT, NMR, b and bc-1 were 3386.61, 0.000486 and 0.000101, respectively. The daily intake of Lys was 291 mg/bird day. Lys was set at 100% for determining the IAAR: 87, 67, 21, 117, 96, 66, 142, 39, and 133 for Met + Cys, Thr, Trp, Arg, Val, Ile, Leu, His, and Phr + Tyr, respectively, for Japanese quail breeders.

Assessment of digestible lysine requirements in lipopolysaccharide-challenged pigs.

To evaluate the effect of an Escherichia coli lipopolysaccharide (LPS) challenge on the digestible lysine (Lys) requirement for growing pigs, a nitrogen (N) balance assay was performed. Seventy-two castrated male pigs (19 ± 1.49 kg body weight [BW]) were allocated in a 2 × 6 factorial design composed of two immune activation states (control and LPS-challenged) and six dietary treatments with N levels of 0.94, 1.69, 2.09, 3.04, 3.23, and 3.97% N, as fed, where Lys was limiting, with six replicates and one pig per unit. The challenge consisted of an initial LPS dose of 30 µg/kg BW via intramuscular (IM) injection and a subsequent dose of 33.6 µg/kg BW after 48 h. The experimental period lasted 11 d and was composed of a 7-d adaptation and a subsequent 4-d sampling period in which N intake (NI), N excretion (NEX), and N deposition (ND) were evaluated. Inflammatory mediators and rectal temperature were assessed during the 4-d collection period. A three-way interaction (N levels × LPS challenge × time, P < 0.05) for IgG was observed. Additionally, two-way interactions (challenge × time, P < 0.05) were verified for IgA, ceruloplasmin, transferrin, haptoglobin, α-1-acid glycoprotein, total protein, and rectal temperature; and (N levels × time, P < 0.05) for transferrin, albumin, haptoglobin, total protein, and rectal temperature. LPS-challenged pigs showed lower (P < 0.05) feed intake. A two-way interaction (N levels × LPS challenge, P < 0.05) was observed for NI, NEX, and ND, with a clear dose-response (P < 0.05). LPS-challenged pigs showed lower NI and ND at 2.09% N and 1.69 to 3.97% N (P < 0.05), respectively, and higher NEX at 3.23% N (P < 0.05). The parameters obtained by a nonlinear model (N maintenance requirement, NMR and theoretical maximum N deposition, NDmaxT) were 152.9 and 197.1 mg/BWkg0.75/d for NMR, and 3,524.7 and 2,077.8 mg/BWkg0.75/d for NDmaxT, for control and LPS-challenged pigs, respectively. The estimated digestible Lys requirements were 1,994.83 and 949.16 mg/BWkg0.75/d for control and LPS-challenged pigs, respectively. The daily digestible Lys intakes required to achieve 0.68 and 0.54 times the NRmaxT value were 18.12 and 8.62 g/d, respectively, and the optimal dietary digestible Lys concentration may change depending on the feed intake levels. Based on the derived model parameters obtained in the N balance trial with lower cost and time, it was possible to differentiate the digestible Lys requirement for swine under challenging conditions.

Comparison of linear and nonlinear models to estimate body weight of Pelibuey ewes from body measurements.

The aim of this study was to develop prediction equations for the body weight of Pelibuey ewes from body measurements comparing linear vs nonlinear models. A subsample of 197 ewes was scored for body weight (BW), rump length (RL), rump width (RW), height at withers (HW), chest girth (CG), chest width (CW), chest depth (CD), cannon bone perimeter (CP), and body length (BL). Pearson's correlation analysis was performed on a sub-data set from 197 ewes to estimate the relationship between body weight and body measurements. Multiple linear regressions were fitted to obtain prediction equations of body weight from the eight body measurements, and prediction equations were obtained from the body measurement that showed the highest correlation with body weight using five nonlinear models allometric, saturation growth, exponential, and incomplete gamma. Data from an independent subsample of 196 ewes was used to validate the equation with the best goodness of fit using linear regression analysis. CG was the body measurement that showed the highest correlation with BW, and based on multiple stepwise regression, in the equation BW = - 60.622 + 1.233CG explained 79% of the body weight variation. Moreover, BW prediction was more accurate when other measurements such CW, BL, and RW were added to the model generating to the equation BW = - 68.875 + 0.845CG + 0.866CW + 0.195BL + 0.601RW (R2 = 0.85, MSE = 15.51). In the case of nonlinear models, incomplete gamma and exponential models generated the equations with the best goodness of fit and precision: BW = 0.077CG1.108exp(0.016CG) (R2 = 0.82, MSE = 18.64) and BW = 3.5759exp(0.0292CG) (R2 = 0.82, MSE = 18.65) respectively.

An Overview of the World Current and Future Assessment of Novel COVID-19 Trajectory, Impact, and Potential Preventive Strategies at Healthcare Settings.

This study is an overview of the current and future trajectory, as well as the impact of the novel Coronavirus (COVID-19) in the world and selected countries including the state of Kuwait. The selected countries were divided into two groups: Group A (China, Switzerland, and Ireland) and Group B (USA, Brazil, and India) based on their outbreak containment of this virus. Then, the actual data for each country were fitted to a regression model utilizing the excel solver software to assess the current and future trajectory of novel COVID-19 and its impact. In addition, the data were fitted using the Susceptible-Infected-Recovered (SIR) Model. The Group A trajectory showed an "S" shape trend that suited a logistic function with r2 > 0.97, which is an indication of the outbreak control. The SIR models for the countries in this group showed that they passed the expected 99% end of pandemic dates. Group B, however, exhibited a continuous increase of the total COVID-19 new cases, that best suited an exponential growth model with r2 > 0.97, which meant that the outbreak is still uncontrolled. The SIR models for the countries in this group showed that they are still relatively far away from reaching the expected 97% end of pandemic dates. The maximum death percentage varied from 3.3% (India) to 7.2% with USA recording the highest death percentage, which is virtually equal to the maximum death percentage of the world (7.3%). The power of the exponential model determines the severity of the country's trajectory that ranged from 11 to 19 with the USA and Brazil having the highest values. The maximum impact of this COVID-19 pandemic occurred during the uncontrolled stage (2), which mainly depended on the deceptive stage (1). Further, some novel potential containment strategies are discussed. Results from both models showed that the Group A countries contained the outbreak, whereas the Group B countries still have not reached this stage yet. Early measures and containment strategies are imperative in suppressing the spread of COVID-19.

Alternative procedure for determining lysine maintenance requirement in poultry

The objective with this study was to determine the lysine maintenance requirements (LMR) of male and female broilers as animal models. A total of 252 birds were used for nitrogen balance trials during three periods (I: 6-21, II: 22-37, and III: 38-53 days). Six lysine levels were used (2.76, 5.88, 8.99, 12.1, 15.2, and 18.3 g kg−1) with six replications. A control group also included, totalizing seven treatments for males and females for each assay. The experimental period was 15 days. The response variables included nitrogen intake (NI) and excretion (NEX), and their difference was assumed to be deposited as nitrogen. An exponential regression between NEX and lysine intake (LI) was fitted, and LMR was estimated when LI = 0. The daily values for LMR were 9.29, 33.4, and 40.2 mg BW0.67 kg−1 for males and 9.36, 30.0, and 39.4 mg BW0.67 kg−1 for females. The final value for both sexes were 10.1 (period I), 31.5 (period II), and 39.8 mg BW0.67 kg−1 (period III). Expressed as body protein weight at maturity (BPm), the LMR were 172 and 148 (period I), 216 and 207 (period II), and 189 and 180 mg BPm0.73 kg−1 (period III) for males and females, respectively. The results provided ranges of LMR values recommended in previous studies, validating this procedure. The procedure to estimate the requirements presented here provides new insights into the model of amino acid requirement estimations.(AU)

Ryegrass (Lolium multiflorum) BRS Ponteio and wheat (Triticum aestivum) BRS Tarumã pasture with different doses of ammonium sulfate as topdressing

This study analyzed the behavior of the annual ryegrass (Lolium multiflorum) BRS Ponteio and dual-purpose wheat (Triticum aestivum) BRS Tarumã with different doses of ammonium sulfate as topdressing and evaluated the exponential growth model to explain the physiological development of both species. For each species, a completely randomized design was used with four replications per treatment with 9m2 area, in which the following treatments were distributed: 0, 150, 250, 350 and 450 kg nitrogen per hectare applied as ammonium sulfate. The cumulative and adjusted productions to the exponential growth model at the end of the cycle were, respectively: BRS Ponteio 150 = 5,620; 250 = 5,920; 350 = 7,585 and 450 = 8,491 and BRS Tarumã 150 = 3,922; 250 = 5,060; 350 = 7,024 and 450 = 7,491 kg dry matter per hectare. The cultivars analyzed without nitrogen application had limited growth and showed no adjustment even to the first order linear model. The application of nitrogen decreased the interval between cuts and increased dry matter production per hectare following the exponential growth model.(AU)

Ryegrass (Lolium multiflorum) BRS Ponteio and wheat (Triticum aestivum) BRS Tarumã pasture with different doses of ammonium sulfate as topdressing

This study analyzed the behavior of the annual ryegrass (Lolium multiflorum) BRS Ponteio and dual-purpose wheat (Triticum aestivum) BRS Tarumã with different doses of ammonium sulfate as topdressing and evaluated the exponential growth model to explain the physiological development of both species. For each species, a completely randomized design was used with four replications per treatment with 9m2 area, in which the following treatments were distributed: 0, 150, 250, 350 and 450 kg nitrogen per hectare applied as ammonium sulfate. The cumulative and adjusted productions to the exponential growth model at the end of the cycle were, respectively: BRS Ponteio 150 = 5,620; 250 = 5,920; 350 = 7,585 and 450 = 8,491 and BRS Tarumã 150 = 3,922; 250 = 5,060; 350 = 7,024 and 450 = 7,491 kg dry matter per hectare. The cultivars analyzed without nitrogen application had limited growth and showed no adjustment even to the first order linear model. The application of nitrogen decreased the interval between cuts and increased dry matter production per hectare following the exponential growth model.

Evaluation of Two Fitting Methods Applied for Thin-Layer Drying of Cape Gooseberry Fruits

ABSTRACT Drying data of cape gooseberry was used to compare two fitting methods: namely 2-step and 1-step methods. Literature data was also used to confirm the results. To demonstrate the applicability of these methods, two primary models (Page, Two-term-exponential) were selected. Linear equation was used as secondary model. As well-known from the previous modelling studies on drying, 2-step method required at least two regressions: One is primary model and one is secondary (if you have only one environmental condition such as temperature). On the other hand, one regression was enough for 1-step method. Although previous studies on kinetic modelling of drying of foods were based on 2-step method, this study indicated that 1-step method may also be a good alternative with some advantages such as drawing an informative figure and reducing time of calculations.

Bayesian path specific frailty models for multi-state survival data with applications.

Multi-state models can be viewed as generalizations of both the standard and competing risks models for survival data. Models for multi-state data have been the theme of many recent published works. Motivated by bone marrow transplant data, we propose a Bayesian model using the gap times between two successive events in a path of events experienced by a subject. Path specific frailties are introduced to capture the dependence structure of the gap times in the paths with two or more states. Under improper prior distributions for the parameters, we establish propriety of the posterior distribution. An efficient Gibbs sampling algorithm is developed for drawing samples from the posterior distribution. An extensive simulation study is carried out to examine the empirical performance of the proposed approach. A bone marrow transplant data set is analyzed in detail to further demonstrate the proposed methodology.

Reevaluation of the digestible lysine requirement for broilers based on genetic potential

Broiler strains available in the poultry industry present different requirements for dietary lysine due to their different growth potentials as a result of their genetic makeup. This study aimed to determine the model parameters for maximum nitrogen retention (NRmaxT), the nitrogen maintenance requirement (NMR) and the efficiency of lysine utilization (bc-1) to reevaluate the lysine (Lys) requirements of male and female broilers. Nitrogen balance trials were performed during three periods (I: 6-21 days, II: 22-37 days, and III: 38-53 days). Seven treatments were used for males and females; the treatments consisted of seven diets with protein levels ranging from 61 to 364 g kg-1 dry matter, with Lys being limiting in the dietary nitrogen (4.91 g of Lys in 16 g of N). Nitrogen intake (NI), excretion (NEX), deposition (ND, ND=NI-NEX) and retention (NR, NR=ND+NMR) values were obtained. The NMR was represented by the exponential relationship between NEX and NI. The NRmax T and bc-1 were estimated by the exponential fit between ND and NI. The NRmax T, bc-1, and NMR values were combined in a model to estimate Lys intake by simulating different percentages of the NRmaxT. The Lys intake estimates were 581, 1,538, and 2,171 mg day-1 for males and 512, 1,340, and 1674 mg day-1 for females during periods I, II, and III, respectively. Due to the flexibility of the model, it is possible to calculate the Lys intake for percentages of NR in the range of practical performance data.(AU)

Reevaluation of the digestible lysine requirement for broilers based on genetic potential

Broiler strains available in the poultry industry present different requirements for dietary lysine due to their different growth potentials as a result of their genetic makeup. This study aimed to determine the model parameters for maximum nitrogen retention (NRmaxT), the nitrogen maintenance requirement (NMR) and the efficiency of lysine utilization (bc-1) to reevaluate the lysine (Lys) requirements of male and female broilers. Nitrogen balance trials were performed during three periods (I: 6-21 days, II: 22-37 days, and III: 38-53 days). Seven treatments were used for males and females; the treatments consisted of seven diets with protein levels ranging from 61 to 364 g kg-1 dry matter, with Lys being limiting in the dietary nitrogen (4.91 g of Lys in 16 g of N). Nitrogen intake (NI), excretion (NEX), deposition (ND, ND=NI-NEX) and retention (NR, NR=ND+NMR) values were obtained. The NMR was represented by the exponential relationship between NEX and NI. The NRmax T and bc-1 were estimated by the exponential fit between ND and NI. The NRmax T, bc-1, and NMR values were combined in a model to estimate Lys intake by simulating different percentages of the NRmaxT. The Lys intake estimates were 581, 1,538, and 2,171 mg day-1 for males and 512, 1,340, and 1674 mg day-1 for females during periods I, II, and III, respectively. Due to the flexibility of the model, it is possible to calculate the Lys intake for percentages of NR in the range of practical performance data.

Fully semiparametric Bayesian approach for modeling survival data with cure fraction.

In this paper, we consider a piecewise exponential model (PEM) with random time grid to develop a full semiparametric Bayesian cure rate model. An elegant mechanism enjoying several attractive features for modeling the randomness of the time grid of the PEM is assumed. To model the prior behavior of the failure rates of the PEM we assume a hierarchical modeling approach that allows us to control the degree of parametricity in the right tail of the survival curve. Properties of the proposed model are discussed in detail. In particular, we investigate the impact of assuming a random time grid for the PEM on the estimation of the cure fraction. We further develop an efficient collapsed Gibbs sampler algorithm for carrying out posterior computation. A Bayesian diagnostic method for assessing goodness of fit and performing model comparisons is briefly discussed. Finally, we illustrate the usefulness of the new methodology with the analysis of a melanoma clinical trial that has been discussed in the literature.

Growth curves of Nile tilapia (Oreochromis niloticus) strains cultivated at different temperatures / Curvas de crescimento de linhagens de tilapias do Nilo (Oreochromis niloticus) cultivadas em diferentes temperaturas

Growth of Red, GIFT and Supreme Nile tilapia strains were evaluated. Fish were cultivated in indoor recirculation systems in 0.5 m³ tanks with controlled temperatures of 22, 28 and 30°C. Random samples of 20 fish from each strain (10 fish tank <->1) were weighed at day 7, 30, 60, 90 and 120. Exponential model (y=Ae x) and Gompertz model (y = Aexp(-Be- x)) were fitted and the estimates parameters were obtained by Weighted Least Squares. At 22°C, Red, GIFT and Supreme strain presented similar growth and fit of exponential model. GIFT and Supreme strain presented higher growth rate at 30°C of cultivation when compared to Red strain. Temperature influences weight and age at the inflection point. The temperature of cultivation influences the growth description of Red, GIFT and Supreme tilapia strains. It changes the age and weight at inflection point and the qualities of growth model fits, changing the variation of the batch.(AU)

Avaliou-se o crescimento de tilápias das linhagens Vermelha, GIFT e Supreme. Os peixes foram cultivados em sistemas de recirculação em tanques de 0,5 m³ nas temperaturas de 22, 28 e 30°C.Amostras aleatórias de 20 peixes de cada linhagem (10 peixes tanque <->1) foram pesadas aos 7, 30, 60, 90 e 120 dias de cultivo. O modelo exponencial (y = Ae x) e o modelo de Gompertz (y = Aexp(-Be <->Kx)) foram ajustados e as estimativas dos parâmetros foram obtidas por Quadrados Mínimos Ponderados. A 22°C o crescimento das linhagens Vermelha, GIFT e Supreme e o ajuste do modelo exponencial foram semelhantes. As linhagens GIFT e Supreme apresentaram maior taxa de crescimento a 30°C quando comparadas à linhagem Vermelha. Pode-se observar influência da temperatura no peso e idade ao ponto de inflexão. A temperatura de cultivo influencia a descrição do crescimento de tilápias das linhagens Vermelha,GIFT e Supreme, alterando a idade e o peso ao ponto de inflexão, a qualidade dos ajustes dos modelos e a uniformidade dos lotes.(AU)

Growth curves of Nile tilapia (Oreochromis niloticus) strains cultivated at different temperatures / Curvas de crescimento de linhagens de tilapias do Nilo (Oreochromis niloticus) cultivadas em diferentes temperaturas

Growth of Red, GIFT and Supreme Nile tilapia strains were evaluated. Fish were cultivated in indoor recirculation systems in 0.5 m³ tanks with controlled temperatures of 22, 28 and 30°C. Random samples of 20 fish from each strain (10 fish tank

Avaliou-se o crescimento de tilápias das linhagens Vermelha, GIFT e Supreme. Os peixes foram cultivados em sistemas de recirculação em tanques de 0,5 m³ nas temperaturas de 22, 28 e 30°C.Amostras aleatórias de 20 peixes de cada linhagem (10 peixes tanque

Comparação entre diferentes métodos de análise do componente lento do consumo de oxigênio: uma abordagem no domínio muito intenso de exercício / Comparison between different methods of analysis of slow component of oxygen uptake: a view in severe exercise domain

O objetivo do presente estudo foi comparar, em domínio muito intenso de exercício, diferentes técnicas utilizadas para medir a amplitude do componente lento (CL) da cinética do consumo de oxigênio. Dez ciclistas treinados, do gênero masculino [média ± DP (idade: 25 ± 3,6 anos, massa corporal: 67,2 ± 4,5kg, altura: 174,8 ± 6,5cm e VO2max: 62,4 ± 3,1ml.kg¹.min¹)], realizaram duas idênticas transições de carga constante (intensidade de 75 por centodelta: 75 por cento da diferença entre o VO2 no limiar de lactato e o VO2max) em dias diferentes. O CL foi calculado a partir de diferentes métodos: (1) modelo biexponencial [VO2(t) = VO2base + A1 (1 e-(t-TA1/t1)) + A2 (1 e(tTA2/t2))], (2) intervalos predeterminados (o deltaVO26-2: diferença do VO2 entre o segundo e o sexto minuto de exercício e o deltaVO263: diferença do VO2 entre o terceiro e o sexto minuto de exercício) e (3) diferença entre o VO2 obtido no final do exercício e o valor obtido a partir de um ajuste monoexponencial do "componente primário" (tempo predeterminado de 120s) (CL6"CP"). Todos os métodos foram comparados entre si. Os resultados demonstraram significante subestimação do CL obtido pelo método de intervalos predeterminados (deltaVO26-2: 432 ± 126ml.min¹ e deltaVO263: 279 ± 88ml.min¹) quando comparado com o modelo biexponencial (676 ± 136ml.min¹) e ao CL6"CP" [(719 ± 265ml.min¹ (p < 0,05)]. Não houve diferenças significativas entre as outras comparações. Os resultados sugerem que a utilização de tempos predeterminados pode subestimar o CL quando comparado com o modelo biexponencial e com o CL6"CP".

The objective of the present study was to compare in severe exercise domain, different techniques used for measuring the amplitude of the slow component (SC) of oxygen uptake kinetics. Ten trained cyclists, male (age: 25 ± 3.6 years, body mass: 67.2 ± 4.5 kg, height: 174.8 ± 6.5 cm and VO2max: 62.4 ± 3.1 mL.kg¹.min¹), performed two identical bouts transitions at constant load [mean ± SD (intensity 75 percentdelta: 75 percent of the difference between the VO2 lactate threshold and the VO2max)] in different days. The SC was calculated from different methods: (1) bi-exponential model [VO2(t) = VO2base + A1 (1 e(tTA1/t1)) + A2 (1 e(tTA2/t2))], (2) predetermined intervals (deltaVO262: difference between the second min VO2 and the end VO2; deltaVO263: difference between the third min VO2 and the end VO2) and (3) difference between the end VO2 and the value obtained from a mono-exponential adjustment of the "primary component" (predetermined time of 120 s) (SC6"PC"). All the methods were compared among themselves. The results showed a significant underestimation of the SC obtained by method of predetermined intervals (deltaVO262: 432 ± 126 ml.min¹ and deltaVO26-3: 279 ± 88 ml.min-1) when compared with bi-exponential model (676 ± 136 ml.min-1) and SC6-"PC" [(719 ± 265 ml.min-1 (p < 0.05)]. There was not significant difference among the other comparison. The results suggest that the use of predetermined time may underestimate the SC when compared with bi-exponential model and SC6"PC".