This study aimed to estimate live body weight from body measurements for Holstein × Zebu dairy cows (n = 156) reared under conditions of humid tropics in Mexico using multivariate adaptive regression splines algorithm (MARS) with several train-test proportions. The body measurements included withers height, rump height, hip width, heart girth, body length and diagonal body length. The data were divided into 65:35, 70:30 and 80:20 split data for training and testing sets, respectively. The MARS algorithm was used to construct a prediction model, which predicted the body weight from the body measurements of the test dataset. The results emphasized that the MARS algorithm had an explanation rate for 80:20 train and test set of 0.836 and 0.711, respectively, with minimum Akaike information criterion values. This indicates that it is a reliable way of predicting body weight from body measurements. The results suggest that body weight prediction can be performed with the MARS algorithm in a reliable way, therefore, this algorithm may be a useful tool for animal breeders and researchers in the development of feeding and selection-aimed approaches.

This study aimed to quantify a latent variable for body size (BS) in pigs by using five linear body measurements including body length (BL), body height (BH), chest width (CW), chest girth (CG) and tube girth (TG), and also to identify the most associated single nucleotide polymorphisms (SNP) and related genes with BS by using the genomic best linear unbiased prediction (GBLUP) based genome-wide association study (GWAS) or GBLUP-GWAS methodology. To perform a GWAS on the BS latent trait, we used a mixed linear model and identified a total of 53 significant SNPs. Additionally, we found that nine genes, including Rho GTPase activating protein 12 (ARHGAP12), transmembrane protein 108 (TMEM108), T-cell lymphoma invasion and metastasis inducing factor 1 (TIAM1), ras homologue gene family member B (RHOB), POU class 4 homeobox 1 (POU4F1), follistatin-related protein 4 (FSTL4), cellular communication network factor 2 (CCN2), beaded filament structural protein 2 (BFSP2) and attractin-like protein 1 (ATRNL1) were associated with the BS trait in pigs. These genes are involved in several biological processes, including the regulation of anatomical structure, morphogenesis, the regulation of cell size and growth. The results suggest that the identified SNP and related genes may play important roles in regulating the growth and development of pigs. The results imply that these genes could be promising candidates for further exploration of the underlying mechanisms of body size variation. Furthermore, the findings have significant practical implications for enhancing the efficiency and profitability of pig farming through genetic selection.

Plane of nutrition (PN) offered to ewe replacements during the rearing phase (8 to 17 months) affects BW at joining and may affect reproductive performance when joined at ~19 months. The effects of PN offered to ewe replacements during their first winter (winter_1) and second summer (summer_2) were evaluated over 3 consecutive years, using 287 spring-born ewe lambs, representing four genotypes (Belclare (Bel), Charmoise×Scottish Blackface (C×SBF), Bel×SBF (Bel×SBF), Bel×SBF that were heterozygous either FecGH or FecXG mutations that increase ovulation rate (OR) (BelMG×SBF)). During extended (deferred) grazing in winter_1 (November to March) the lambs were offered herbage DM allowances (HA) of 0.75 (L) or 1.75 (H) kg/day. During summer_2 (March to August) the replacements were set stocked to maintain sward heights of 4 (L) or 6 (H) cm, thus yielding a 2×2 factorial design for the nutrition treatments (71 to 73 animals/treatment). Increasing HA during winter_1, and residual sward height during summer_2, increased (P<0.001) BW and body size at joining (19 months) but had no effect (P>0.05) on OR. Mean BW at joining was 53.3, 56.8, 56.6 and 61.7 (SEM 0.74) kg for ewes offered the LL, LH, HL and HH treatments, respectively. Mean OR of C×SBF and BelMG×SBF differed (P<0.001) from that of Bel×SBF by −0.58 and +0.47, respectively. Correlations between linear measurements (LMs) of body size and BW at 7, 12 and 17 months were all positive and significant (P<0.001). The precision of the set of LMs as a predictor of BW at joining improved with age (R2 0.46, 0.54 and 0.74 at 7, 12 and 17 months) but BW at a given age was a better predictor at all age time points. Chest girth was the best predictor, among the LMs, of BW at joining and its explanatory power increased with age. Equations developed using LMs at 7, 12 or 17 months, to predict BW at joining exhibited biases of −2.1, −1.5 and +0.9 kg, respectively. It is concluded that whilst altering PN during the rearing phase changed BW by 16% it had no effect on OR. There was no interaction (P>0.05) between the PN offered during winter_1 and summer_2, or PN and ewe genotype for BW at joining or OR. LMs, either at 7, 12 or 17 months of age, are useful predictors of BW at joining.

This study aimed at using a multivariate approach to describe the body structure of Djallonke sheep in northern Ghana and to determine which approach explains better the variation in body composition. Live weight (LW) and linear body measurements including heart girth (HG), neck girth (NG), chest depth (CD), height at withers (HW), rump height (RH), body length (BL) and pin-bone width (PBW) were obtained from 172 sheep aged between two and three years. The fixed effects of sex and age were tested using the general linear model (GLM) while the Nearest Neighbor method of Hierarchical Cluster Analysis was used to group body traits into clusters. Principal Component Factor Analysis was used to describe the variation in body traits where extracted factors were varimax rotated to enhance interpretability. The analysis of variance revealed significant (P < 0.01) differences in the morphological traits of the two sexes with higher values recorded for the male in all traits examined except in PBW, which was insignificant (P > 0.05). Age had no significant influence (P > 0.05) on the body traits. The sheep weighed 26.92 ± 0.89 kg averagely and had averages of other body measurements to be: 71.74 ± 1.23, 40.52 ± 0.79, 27.73 ± 0.52, 60.72 ± 0.86, 59.61 ± 0.87, 58.87 ± 1.06 and 12.81 ± 0.23 cm for HG, NG, CD, HW, RH, BL and PBW, respectively. The product moments of correlation were positive and significant (P < 0.05, 0.01; r = 0.18–0.99) for all pairs of traits. The body traits were categorized mainly into two clusters with the first cluster comprising the HG, HW, RH and BL while NG, CD and PBW formed the second cluster. The grouping of the traits was slightly different in Factor analysis where two underlying principal components (PC) were extracted to discern the variance structure of the Djallonke sheep. The first principal component which consisted of CD, HW, RH, BL and PBW explained 61.26 percent and the second, 12.92 percent thereby giving a maximum of 74.17 percent generalized variance in body measurements. The traits loaded on the first principal component are closely associated with bone growth hence describing the general body size conformation while the traits (HG and NG) on the second component seem to describe only the thoracic region. It can be concluded that both the Hierarchical Cluster analysis and the Factor analysis grouped body traits similarly but the later is to be recommended because of the additional ability of indicating the amount of variation explained by the developed factors.

A total of 700 adult female goats from Sétif area (Algeria), were investigated for eight qualitative morphological traits and 17 body measurements. Sampling included three environmental areas: Northern, Central and Southern area. Coefficients of variation ranged from 10.9 percent to 34.7 percent, showing high heterogeneity. Canonical analyses showed that differences in body measurements between the three area-populations were large and significant in all traits (P < 0.001). The shortest Mahalanobis distance was found between North-Center populations (2.8), while that between Center (4.0) and (8.6) between North-South populations were the largest. Discriminant analysis showed that most goat-populations were classified into their environmental-area, North (73.0 percent), Center (66.8 percent) and South (79.3 percent) with a few misclassified individuals. Correspondence analysis indicated no large differences between the goat populations; they were more homogeneous for qualitative traits. This information will constitute the basis for further characterization and develop conservation strategies for Algerian goat populations

A household survey and measurements of different body traits from 120 households and from 1 009 goats were collected to characterize the production system and morphological features of Western lowland and Abergelle goat breeds of Ethiopia. Goats were kept for multifunctional roles in both areas, but mainly to generate cash. The average ± SD of flock sizes per household were 10.8 ± 7.25 and 48.56 ± 52.21 for Western lowland and Abergelle, respectively. Production characters such as body conformation, multiple births and milk yield were reported as major selection criteria of breeding goats. The majority of Abergelle goats have red brown (23.8 percent) and brown (19.7 percent) coat colours with short and smooth hair. All Abergelle goats have horns, 11.1 percent have wattles, 8.0 percent of males have ruff. White (20.4 percent) and a mixture of white with other colours were the predominant coat colours of Western lowland goats. A total of 42.3 percent males and 5.1 percent females of the Western lowland population have ruff. The least square means of body weight, chest girth, body length and height at withers of Western lowland female goats were 24.00 ± 0.19 kg, 65.27 ± 0.23 cm, 54.8 ± 0.21 cm and 62.60 ± 0.22 cm, respectively. The corresponding values for Abergelle female goats were 18.34 ± 0.22 kg, 61.03 ± 0.27 cm, 51.00 ± 0.24 cm and 58.99 ± 0.25 cm, respectively. Breed improvement programmes in these areas should take into account the multifunctional roles of goats, goat breeding practices and traits preference of the farmers.

Assessment of diversity is a prerequisite for the management and conservation of farm animal genetic resources. To study the morphological features of Fipa cattle in Southwestern Tanzania, 108 herds were studied. Fourteen body measurements (body weight, body length, height at withers, heart girth, ear length, ear width, horn length, horn-base thickness, horn-base spacing, horn-tip spacing, rump width, rump length, tail length and tail-base thickness) and qualitative traits were recorded from 307 animals. Measurements were classified according to location and animal sex. Both location and sex significantly (P < 0.05) influenced all the measurements, with castrates and bulls superseding cows. Most measurements were positively and highly significantly (P < 0.001) correlated with the body weight predicted accurately from heart girth. The animals had variable colour patterns, but being predominantly red (20.9 percent), pied black and white (18.6 percent), black (17.9 percent) and pied red and white (14.7 percent). All animals had sloping rumps and most (81.8 percent) had small-sized humps. Most (94.8 percent) animals had pyramid-shaped humps located in the cervico-thoracic position. Most (91.5 percent) animals had upward–forward oriented and lyre-shaped horns. All the animals had flat faces and backs, and laterally oriented ears. Most (97.1 percent) animals had medium-sized dewlaps, medium-sized teats (93.6 percent) and medium-sized quarters (87.2 percent). The navel flap was absent in most (87.6 percent) animals. Thus, the Fipa cattle can be classified as a medium-sized strain with considerable variation in body size and morphological features within and between districts.

Dirty udders and teats result in a higher workload in terms of cleaning before milking and may constitute a risk for udder health. The aim of this prevalence study on 23 farms with very low within-farm variation in cubicle measures and other cubicle characteristics was to identify potentially influencing housing and management factors concerning teat and teat tip soiling. Information about udder soiling, housing and management was collected through direct recording and farmers’ interviews. Height at withers, shoulder width and diagonal body length were measured in 79% to 100% of the cows in each herd. On the basis of the 25% largest animals, compliance with recommendations for cubicle measures was calculated, which was generally rather low. Stepwise regression was used to find predictors for the percentage of dirty teats and of dirty teat tips. The final model on dirty teats explained 58.5% of the variance and contained four factors (F = 6.34, P = 0.0023). Less soiled teats were found on farms that conducted teat dipping after milking (t = −3.21, P = 0.0048), had increased daily cubicle maintenance time (t = −2.58, P = 0.0187), deep-bedded cubicles (t = −2.42, P = 0.0265) and decreasing compliance concerning cubicle length (t = 2.33, P = 0.0317). The final model on teat tip soiling explained 46.0% of the variance and contained three factors (F = 5.39, P = 0.0075). Less soiled teat tips were associated with increasing height of bedding material (t = −2.89, P = 0.0094) and decreasing compliance concerning resting length (t = 2.12, P = 0.0470). Difficult to explain was the association found between increased passage soiling and decreased teat tip dirtiness (t = −1.86, P = 0.0790). Thus, even under relatively restrictive cubicle conditions, a certain increase in teat and teat tip soiling was found with increasing cubicle length. However, at the same time, measures relating to good management may positively affect teat and teat tip cleanliness. In addition, deep-bedded cubicles yielded advantages in this regard. Both regression models for teat and teat tip cleanliness contained similar but not identical predictive variables. This indicates that dirtiness of each particular area may originate from slightly different though related causes. The low correlations found between udder, teat and teat tip cleanliness should be considered in future studies.

The current study proposes a method for the morphological characterization of chicken. It involves the measurement of 25 variables, 12 from head measures and the other 13 from rest of the body. This method was used to compare two Catalonian autochthonous chicken breeds: partridge Penedesenca and blond Empordanesa with measurements of 30 hens each. Measurements were taken by two operators, each measured 15 hens per breed. Hens were 30 weeks old, and were bred under the same conditions. As a whole the results showed us that both breeds are very similar morphologically. Nevertheless, nine variables were different between the two breeds and six were different between the two operators, most of them were head measurements. So it is suggested that the measurements on head must be accurate. Only four variables, beak length and width, comb width and ear lobes length, showed interaction among the factors that do not allow us to address the differences between the breeds. The comparison results between Empordanesa and Penedesenca showed that Empordanesa had higher values in wattle length, wattle width and ear lobes width than Penedesenca. Regarding the corporal measures, Empordanesa had higher values of the folding wing and tarsus diameter than Penedesenca although Penedesenca had larger values in keel of sternum length and breast angle than Empordanesa. Empordanesa was a little heavier than Penedesenca.

The relationship among parasitological parameters, abomasal size and body size measurements was investigated in lambs following an experimental infection with Haemonchus contortus. In total, 100 lambs from five different genotypes (German Merino (GM), Texel × GM, Suffolk × GM, German Blackhead Mutton × GM and Ile de France × GM) were experimentally infected with 5000 infective third stage larvae of H. contortus at the time of weaning at 12 weeks of age. Four and six weeks after infection, individual faecal samples were collected for estimation of faecal egg counts (FECs). Furthermore, wither height, shoulder width, heart girth, loin girth and body length were taken at 18 weeks of life. Lambs were slaughtered and necropsied 7 weeks post-infection, and worm counts, abomasal volume and surface area were determined. Positive correlations were found between different body size parameters, body weight and abomasal sizes. FEC and worm counts were not significantly correlated either with body size parameters or with abomasal size. The mean worm burden was higher in GM than in crossbred lambs. There was no significant difference in abomasal size between GM and crossbred lambs. The results suggest that the variations between animals in worm burden following an experimental infection with H. contortus (worm resistance) are not influenced by body size parameters or abomasal sizes. Therefore, other factors, including genetic-based differences in resistance, must cause these findings between and within breeds.

Specific procedures are described to measure the body dimensions of large African predators; these include measurements of body and tail length, head, canines, mane, limbs, paws and testes. Data on body mass and dimensions were collected from an immobilized sub-adult male African lion Panthera leo. He was 40 months old and weighed 190 kg. After being immobilized, data on body mass and dimensions were collected by a team comprising a scribe, two operators and assistants. The procedures of measuring the 43 variables on body dimensions were then repeated three times in quick succession, each session lasting about 10 min. The four sessions were handled as if a different individual was measured each time. Except for reports on body mass of lions, there is a paucity of comparable data in the literature for most of the variables presented in this paper. The small dispersion measures of the 43 variables suggest that the specific procedures to measure the body dimensions of a large African predator such as the lion have a high degree of repeatability and can be applied with confidence. The procedure has been used to obtain data on body dimensions of a large number of lions as well as dead specimens of black-backed jackal Canis mesomelas, caracal Caracal caracal and Cape fox Vulpes chama. The data form part of a database on body dimensions of large African predators created by ALPRU. The objective is to develop non-invasive techniques to determine whether wild predator populations might have been subjected to abnormal growth and development as a result of negative impacts on their habitat and thus food base.

In the double-muscled (DM) Belgian Blue beef (BBB) breed, caesarean section (CS) is being applied systematically as a management tool to prevent dystocia. As a matter of fact, CS is the only possible way of calving in the breed. High birth weight and a relatively small pelvic area are the main causes of dystocia and, in the DM-BBB breed, the reasons for the systematically applied CS. Selection for lower birth weight and larger pelvic sizes might reduce dystocia and routine CS. Few data on inner pelvic sizes of pedigree animals are available. Using external measurements to estimate the inner pelvic sizes might be an option to resolve this problem. In this study, animals of the DM-BBB breed were measured and weighed on farms and in abattoirs. External and internal pelvic sizes increased with live weight and age of the animals. Gender had a significant influence on inner pelvic traits. Increased muscular conformation was associated with decreased inner pelvic dimensions. Models with weight, gender, age, withers height and outer pelvic width (TcTc) can be used to estimate inner pelvic sizes (R2 between 0•35 and 0•77). The estimated inner pelvic sizes can then be used to genetically evaluate pelvic traits in the DM-BBB breed. Improving weight, withers height and TcTc width in combination with lowering muscular conformation may help to decrease the high rate of caesarean section in the DM-BBB.

Goat production systems increasingly involve indoor feeding. To facilitate manger design, there is need for information on the ability to reach for food, such as that for cattle given food through tombstone barriers. In the first study, 20 castrated and 20 non-pregnant female Saanens of mean live weight (M) 39·3 (s.d. 14·42) kg were trained to reach, through a vertical tombstone barrier, for concentrate meal placed on a horizontal platform attached to the barrier. The barrier allowed the neck but not the shoulders to pass through. It was hypothesized that horizontal reach forwards (F, distance from mid point of barrier to uneaten meal) and sideways (S, distances sideways from mid point of barrier to uneaten meal adjacent to barrier) would be a function of height of platform above the floor and size of goat. Because of size, eight goats (mean M, 16·4 kg) were unable to reach meal when the platform height was 75 cm. Mean (s.e.) values for F at platform heights 0, 25, 50 and 75 cm were 55·9 (0·68), 58·8 (0·64), 57·8 (0·69) and 41·1 (1·23) cm respectively. Values for S were smaller, but followed a similar pattern (49·4 (0·64), 52·4 (0·56), 53·2 (0·53), 36·6 (1·17) cm). Linear regression of either F or S on M and linear body dimensions (e.g. body length, neck and head length, neck-joint height, withers height) showed high correlations with R2 values being 0·8 or more. In the second study, 10 castrated and 10 non-pregnant females (M, 48·7 (s.d. 14·56) kg) were trained to reach through the tombstone barrier for concentrate pellets 'glued', using molasses, on to a vertical plate. It was hypothesized that vertical reach (V, distance from floor to uneaten pellets) would be a function of distance between barrier and plate (20, 30, 40, 45, 50 cm), height of step (0,14·2, 28·4, 42·6 cm) on which goats placed their forelegs and size of goat. Four goats (mean M, 29·9 kg) were unable to reach pellets when the plate was at 45 and 50 cm. Mean (s.e.) V values decreased with increasing plate distance and increased with step height (e.g. at 0 cm step, 122·4 (1·96), 116·9 (2·05), 109·4 (2·16), 103·9 (2·49) and 96·5 (2·75) at 20-; 30-; 40-; 45- and 50-cm plate distances respectively; at 20-cm plate distance, 122·4 (1·96), 137·5 (2·00), 151·3 (1·90) and 164·3 (2·00) cm at 0-; 14·2-; 28·4-and 42·6-cm step heights respectively). Linear regression of V on body weight and body dimensions (e.g. body length, heart girth, withers height) showed high correlations (R2 > 0·8). It is concluded that for practical purposes, body weight is a satisfactory predictor of reach. The results support the hypotheses. The data will facilitate the design of mangers for goats with body weights and dimensions in the range of those used in the present study.

The change in the proportional distribution of bone weight within the carcass skeleton from birth to maturity was examined in rams and ewes from flocks of Australian Merino sheep selected for high (weight plus) and low (weight minus) weaning weight and from a randomly selected control flock. Data from 140 animals (106 immature, 34 mature) were used. Shape parameters for the long bones of the limbs in the 34 mature animals were derived by determining the allometric relationship between bone length, diameter and individual bone weight.

Selection for increased and decreased weaning weight resulted in a concomitant increase and decrease in mature size and total bone weight. In the weight plus group, total bone as a proportion of body weight also increased but selection had little effect on the proportional distribution of bone weight within the skeleton at any stage of maturity. This was the product of similar growth patterns within the skeletal system aiming towards a similar mature distribution pattern for each strain.

Within the strains of different mature size there was a difference between mature rams and ewes in both total bone weight as a proportion of body weight and in the proportional distribution of this bone weight. This was associated with differences in the maturing patterns of the bones of the hindlimb and the pelvic girdle.

Neither selection nor sex affected the relationship between bone shape and bone weight, although the difference in bone weight between the strains and sexes at maturity meant that they also differed in bone shape at this point.

Sheep of three hill breeds and the crosses among them were closely inbred for four generations to create five levels with inbreeding coefficients 0·0 (F2/O2), 0·25 (I1,), 0·375 (I2), 0·50 (I3), and 0·59 (I4). Inbred females were also mated to unrelated inbred males of the same breed or crossbred type to produce line-crosses (LC). Mating was arranged so that the effects of inbreeding on the individual could be differentiated from maternal inbreeding. A total of 2369 animals were available up to 78 weeks of age and 1062 to the age of 4 years. This study examines the effects on six linear body dimensions and draws comparison with the effects on body weight. There were significant reductions in the size of the body dimensions with increasing inbreeding but the maximum depression was usually at the I2 stage for individual inbreeding and the I3 stage for maternal inbreeding. Most of the linear and many of the non-linear effects of inbreeding of the individual were significant and the effects of maternal inbreeding were also significant in a majority of cases. Inbreeding effects were more marked for relatively late-maturing parts (shoulder and hook widths) than for early-maturing (cannon bone and tibia lengths) with head width and body length intermediate but closer to the early-maturing parts. This was seen separately at each age, and in the effects of advancing age. By 78 weeks of age, the effects of inbreeding of the individual on absolute size had increased with age and by 4 years of age, in spite of a small recovery in size relative to F2/O2, was still greater than in early life. The effects of maternal inbreeding became progressively less with advancing age relative to non-inbreds. The changes with inbreeding could not be explained by dominance effects alone and epistasis is therefore likely also to be involved.

Insulin-like growth factor 1 (IGF1) correlates with antler growth and body growth in penned red deer stags. The present study aimed to investigate the relationships among plasma concentration of IGF1, body growth and carcass composition in grazing stags. Twenty-eight 10-month-old stags were kept at pasture from September to February. They were bled, weighed and their antlers measured fortnightly. Plasma was analysed for total IGF1. All stags were slaughtered in February (aged 15 months); organ weights were recorded and the carcasses were analysed chemically for water, fat and ash. The stags began the study weighing 60·7 (s.e. 1·4) kg and were 96·3 (s.e. 2·0) kg at the end. They grew rapidly in spring and early summer but growth rate slowed in mid summer before increasing again in late summer.

Total plasma 1GF1 for each stag throughout the study correlated positively with antler length (P < 0·001), total live-weight gain (P < 0·001), hot carcass weight (P < 0·01), fat-free carcass weight (P < 0·01), carcass fat weight (P > 0·05) and carcass fat percentage (P > 0·05). Thus IGF1 correlated significantly with all measures of body weight except fat. IGF1 correlated positively with antler growth rate (P < 0·001) calculated individually for each stag during each fortnight. IGF1 correlated positively with the spring phase of live-weight gain calculated as above (P < 0·001) but negatively (P < 0·01) with live-weight gain during the late summer growth phase. The relationships between IGF1 and growth in penned stags also pertain in grazing animals, and in addition 1GF1 is closely associated with carcass lean mainly via an overall effect on body size.

One hundred and thirty-six multiparous cows, 63 goats and 71 sheep were measured in breeding flocks and herds in Nigeria. The humped cattle breeds, and the large-bodied, humpless Kuri, are narrow-bodied and tall in relation to their length when compared with British breeds. Pelvic dimensions are small. The sheep and goats native to the coastal and middle belts (the West African Dwarf breeds) are miniature versions of those found in the north. Neither appears to be achondroplasic but dwarfing seems to have proceeded differently in the two species in that the adult West African Dwarf goat is similar in its relative body proportions to the adult northern goat, implying a proportional miniaturization. The West African Dwarf sheep appears to be a neotenous form with body proportions similar to those of an immature sheep.

The body dimensions and live weight of 126 Mule (Bluefaced Leicester × Scottish Blackface) and Scottish Blackface ewes were measured during the 1986/87 housing season. Body dimensions included: head and neck length, body length, diagonal body length, height to withers, height to rump, girth at widest point, heart girth, width at widest point and width at shoulders. It was found that most body dimensions varied greatly with body weight. However, some body dimensions such as head length were found to be independent of weight within the weight range studied. Prediction equations are presented for each body dimensions for unshorn sheep.

These predictions can be used as a basis for the design of sheep housing, for example, trough space allowances, design of feeders or as a biological basis for space allowance.

To study genetic contribution to complex body size traits, the intrafamilial correlation and regression analyses along with twin study method have been used. The data are based on a sample of 45 MZ and 101 DZ twin pairs, their 125 singleton siblings, 104 fathers and 103 mothers in 146 Punjabi families living in Chandigarh, India. Twin study gives no evidence of inequality of means and variances between zygosities. Within-pair genetic variance ratios, correlations, regressions of offspring on midparent and single parent are all significant at 0.1%, thus indicating strong genetic component. Heritability estimates are higher for longitudinal body traits than the breadth dimensions. The resemblance of the children with the parents of either sex is not equal. Higher maternal influence is indicated for a number of body traits. The results on familial correlations do not support the hypothesis of sex-linked inheritance for any of the traits considered in this investigation. These results have been compared with those from other such studies.

A study of 100 MZ and 67 DZ twin pairs aged 18 to 25 years has shown a highly significant genetic contribution to the following measurements: standing and sitting height; height on tragus; arm length; biacromial, biiliac, and bitrochanteric diameter; weight; circumference of thigh and of upper arm relaxed and contracted; and head length and breadth. The twins were brought up together and of the same socioeconomical, geographical, ethnical, and cultural origin. Zygosity diagnosis was based on 22 to 26 blood groups. The means of the measurements were smaller in MZ than in DZ twins, some of them significantly so. The intraclass correlation coefficients of the MZ cotwins were all significant and greater than those of the DZ cotwins. In families of same geographical origin, sib-sib correlations were somewhat smaller than those of the DZ cotwins, but for the three diameters of the body the order was reversed.