Prediction of body weight from linear body measurement in two breeds of cattle

The study compared live weight and linear body measurements of two breeds of cattle (White Fulani and Muturu Cattle) and regressed linear body measurements on live weight. A total of eighty-six cattle of forty-three per a breed were reared at the cattle production unit of the Teaching and Research Farm, Akwa Ibom State University – Obio Akpa Campus, Nigeria in a semi intensive management system. Parameters measured were; live weight (LW), face length (FCL), head circumference (HC), ear length (EL), neck length(NL), neck circumference(NC), height at wither(HW), body length(BL), body circumference(BC), hind limb(HL), fore limb(FL), and tail length(TL). The data obtained were subjected to statistical analysis for morphometric traits and prediction was done through linear model regression method using SPSS statistical software package. Breed of cattle significantly (P>0.05) affected all linear body measurements and live weight exception of NL .Linear body Parameters of both breeds were compared. The mean live weight of White Fulani and Muturu were 251.28kg and 149.81kg, respectively. Means of FL, EL, NL, BL, HL, TL and BC, NC and HW of White Fulani were significantly (P<0.01) higher than Muturu breed but the HC of Muturu was significantly (P<0.01) higher than White Fulani breed. Muturu breed had higher R2 of 0.98 in BL and BC than White Fulani breed. In conclusion, White Fulani was considered a larger breed than Muturu cattle. Live weight can be accurately predicted from linear body measurements through BC and BL in both breeds.

Study of Body Conformation of Carpet Wool Type Chitarangi Sheep of India using Principal Component Analysis

Background: The principal component analysis is applied to identify minimum number of combined variables that account for maximum portion of the variance existing in all variables studied. Chitarangi is a lesser known carpet type wool sheep distributed in Fazilka and Muktsar districts of Punjab, Sri Ganganagar district of Rajasthan and the adjoining areas. The information on body biometry is a prerequisite to characterize the lesser known sheep population available in the country. Hence, it is important to describe the body conformation by recording minimum number of biometric traits. Methods: Body biometry traits of Chitarangi sheep, a lesser known carpet quality wool producing sheep population were studied using Principal Component Analysis. The traits studied were body length (BL), height at wither (HW), chest girth (CG), paunch girth (PG), ear length (EL), face length (FL), face width (FW), tail length (TL) and adult body weight (BW). The data were collected on 297 ewes in the breeding tract of Chitarangi sheep. The descriptive statistics were determined for all the traits. The phenotypic correlations between different body biometric traits were estimated using partial correlations. Principal components were estimated using correlation matrix. Principal component analysis (PCA), a multivariate approach, is used when the recorded traits are highly correlated. Rotation of principal components was through the transformation of the components to approximate a simple structure. Factor analysis using oblique (promax) rotation was used. All the analysis was carried out using the SPSS statistical package. Result: The averages for body weight and biometry traits confirmed large size of Chitarangi animals. Most of the phenotypic correlations amongst the studied traits were positive and significant (p less than 0.01). The three components extracted from nine principal components accounted for 69.06% of the total variance. The first component, which described body size of ewes, accounted for 43.68% of the total variation with high loading for BW, CG, PG, HW, BL and FL. The components two and three explained 13.54 and 11.83% of total variance, respectively. The communalities ranged from 0.490 (FL) to 0.888 (PG). The lower communalities for face length indicated lower contribution of the trait to explain the total variation than others. The study indicates that principal components provided a means of reduction in number of biometric traits to explain body confirmation of adult female Chitarangi sheep.

Longwall Top-Coal Caving Mechanism and Cavability Optimization with Hydraulic Fracturing in Thick Coal Seam: A Case Study

Longwall top-coal caving mechanisms and cavability optimization with hydraulic fracturing are analysed in this study. Based on the geological and geotechnical conditions of the Dongzhouyao coal mine, it is revealed that top-coal failure mechanisms are dominated by both compressive and tensile stresses. Ahead of the face line, shear failure initiates at the lower level of the top-coal and propagates to the upper level. Compressive stress-induced damage leads to obvious deterioration in tensile strength, causing the onset of tensile failure in the top-coal behind the face line. Accumulated plastic strain (APS) is selected as a top-coal cavability indicator. The cavability degrades gradually at the higher elevation of the top-coal while it is greatly strengthened as the top-coal approaches closer to the face line. In a thick coal seam without hydraulic fractures, the maximum APS occurs at the middle section of the face length in the Longwall top-coal caving (LTCC) panel. After hydraulic fracturing, top-coal cavability is significantly enhanced. But the spatial distribution of the APS transitions from uniform to non-uniform type due to the existence of hydraulic fractures, causing great variety in the cavability along the panel width. With increasing fracture intensity and fracture size, the failure zone expands significantly ahead of the longwall face, which means the cavability becomes increasingly favourable.

Effect of Face Length in Initial Mining Stage of Fully Mechanized Top-coal Caving Face With Large Mining Height

Based on the field measurement of the end resistance of the support during the initial weighting of the basic roof and the macroscopic mine pressure behavior during the weighting period of 101,22211,103 and 301 fully mechanized caving face in Changchun Xing Coal Mine, the mine pressure law of the working face is summarized and compared, and the relationship between the working face length and the working resistance of the support ( the weighting strength ) and the macroscopic mine pressure behavior is obtained. In the range of face length 126-230 m, with the increase of face length, the end-of-cycle resistance of the support gradually increases and the dynamic load coefficient of the support gradually increases when the coefficient of the support gradually increases, and the strata behavior of the working face changes from strong to very strong. When the face length is short ( 126-140.5m ), the hanging top area is too large to cause hurricanes when the working face is pressed, which threatens and damages the personal safety and equipment of the working face staff. Based on the above research, the problem of optimizing the surface length is proposed, and the surface length is determined to be within the range of 140-230 m according to the measured results.

Study on the Law of Earth’s Surface Movement on Ultra-long Working Face

The problem of stoping on ultra-long working face is one of challenges for making coal mining safe and efficient. The strong mining effect of surrounding rock induced by long working face mining causes a number of coal or rock dynamic disasters to safe and efficient coal mining. For the purpose of in-depth study of the law of earth’s surface movement on ultra-long working face, this paper, with FLAC3D (numerical simulation software) used to build a numerical model of ultra-long working face, analyzes the law of roof-to-floor strata behaviors in coal bed during mining, and studies the weakening of roof-to-floor parameters in coal bed, bearing pressure and the law of roof caving and rock strata movement; Analyzes the face length effect resulted from the difference in face lengths. It has been recognized that the sphere of influence of bearing pressure changes from small to large and then to small, and changes in distribution of arch bottom and arch height at the plastic failure zone are further intensified over advancing of the working face, moreover, the movement of rock strata is subject to the cumulative influence of the advancing direction of the working face and the face length effect. The above-mentioned research results can serve as a theoretical basis for practical engineering.

Multiple Influence Factor Sensitivity Analysis and Height Prediction of Water-Conducting Fracture Zone

To explore the influence law and sensitivity of various factors on the height of the water-conducting fracture zone, and further predict the development height of the water-conducting fracture zone, taking the field survey and collected actual measured data as the research foundation, establishing mathematical model, regression analysis, and field measurement were adopted comprehensively. Based on the Data Processing System (DPS), influence factors of the development height of the water-conducting fracture zone were analyzed. By introducing sensitivity coefficient, a sensitivity quantification mathematical model was established, and sensitivity ranking was obtained. The regression relationship between each factor and the height of the water-conducting fracture zone was obtained by single factor analysis. Based on this, the prediction formula was proposed and successfully used in the field practice. Results show that the sensitivity coefficient of mining thickness, ratio coefficient of hard rock lithology, mining depth, and length of working face was 0.75, 0.69, 0.66, and 0.58, respectively. The dispersion degree of working face length and mining depth was greater than that of ratio coefficient of hard rock lithology and mining thickness. To some extent, it also reflects that the sensitivity of working face length and mining depth to the height of the water-conducting fracture zone was the weakest, which was consistent with the previous conclusions. Using the multiple regression mathematical model, a nonlinear statistical relationship between the height of the water-conducting fracture zone and ratio coefficient of hard rock lithology, mining thickness, working face length, and mining depth was obtained. This research provides some scientific basis and guidance for safe and efficient underwater mining.

Presence or Absence of Earlobes Reveals Different Biometric Structure among the Peluca Hen from Guatemala

Background and Objective: Earlobe, a head furnishing trait, is a non-putative trait in Peluca hen (“naked-necked” hen), a local breed from Guatemala. The objective of this study is to determine if presence or absence of earlobe is linked to a body linear trait. Materials and Methods: Quantitative data collected on 311 mature hens belonging to Peluca breed were subjected to analyses for two different phenotypic subsets according to presence/absence of earlobes (212 with earlobes and 99 without earlobes). Measured morphometric traits were 18: Weight, Perimeter, Length, Width and Height of Body, Wing Length, Leg Length, Lengths of Head, Beak and Face, Length and Width of Shank, Metatarsal Perimeter, Dorso-sternal Height, Bicostal Length, Withers Height, and Thoracic and Abdominal Perimeters. A Principal Component Analysis was applied to the study of variable between both groups to explore the relationship between traits. Results: body length and height, and abdominal and thoracic perimeters were the most discriminative traits between groups. “Non-lobe” group presented significative higher values only for body length. Conclusion: Presence/absence of earlobes describe a different body structure within the Peluca hen. Moreover, as this represents no adaptative response, presence or absence of earlobe must be considered to be more related to the productive aptitude rather than different ecotypes. This association of earlobe with some body traits is important since it can ease the task of selecting productive characteristics of the “Peluca” hen.

An Influence Study of Face Length Effect on Floor Stability under Water-Rock Coupling Action

The Taiyuan Formation limestone aquifer and Ordovician limestone aquifer are widely distributed in the coal seam floor of coal measures in North China; the water hazard safety problem of the stope floor under the influence of mining is very prominent. The risk of the water inrush from the coal seam floor is closely related to the degree of full exploitation, so it is necessary to study the stability of the stope floor under aquifer conditions, especially the influence of the working face length effect on floor stability. Through numerical simulation of water-rock coupling action, the mine pressure behaviors of the water-resisting floor under different face lengths were analyzed based on the measured formation permeability coefficient. The Fish program was used to adjust rocks entering the plastic failure state into a strain softening model to investigate the influence of the face length effect, the damage degree of the water-resisting floor, and the morphology and deformation bearing capacity of the failure zone. The results show the following: (1) the face length effect is one of the main influence factors of the failure mode and failure degree of surrounding rocks in the stope; (2) as the face length increases, the obvious pressure relief zone of surrounding rocks presents a staged change, and the obvious pressure relief zone at the seam roof and floor is in an obvious “reverse saddle shape”; (3) the closer to the seam floor, the more remarkable the rock softening characteristic because of the compaction action of gangues caving from the roof; and (4) the rock mass close to the seam floor undergoes local tensile failure, and the water-resisting floor near the coal wall at two sides mainly bears compaction-shear action, leading to compression-shear failure of the rock mass at the floor and formation of water-conducting fractures. The study results can provide a reference for taking precautionary measures of safety mining above a confined aquifer.

The effects of genotype and week of lactation on milk yield, udder dimensions and linear body measurements of non-dairy ewes

One hundred and ninety two records were taken weekly for twenty four (24) weeks from West African Dwarf (WD), the Yankasa (YN) and the West African Dwarf X Yankasa crossbred (XB) sheep. The traits evaluated were milk yield (MK), linear body measurements (LB) such as height at withers, (HT), body length (BL), heart girth (HG), shoulder width (SW), Tail length (TA), Neck length (NL), Neck circumference (NC), Face length (FA), Hind leg length (HL), Foreleg length (FL), Face length (FA), Ear length (EA), Head width (HW) and Rump height (RH) together with the following Udder dimensions (UD): Udder circumference (UC), Teat length (TL) and Teat circumference (TC). There was significant (P<0.05) influence of genotype on MK, WHT, HT, BL, TA, FL, HL, FA, EA and RH. The WD ewes produced more milk than either the YN or XB enes. Average daily milk yield (ml) was 122.25, 90.88 ana 108.8. The YN genotype was superior in all LBs except SW and NC than the WD and XB in the three genotypes. Height at withers was 59.08, 69.21 and 61.81 cm; BL 48.54, 55.08 and 54.49 cm and RH 62.88, 75.11 and 68.46 cm for WD, YN and XB enes respectively. Since milk offtake is related to body weight and some linear body measurements, selection for WT, HG, SW, NL NC, UC and TL in WD ewes could lead to higher milk and mutton production.