The thickness of cattle skin

1955 ◽  
Vol 6 (5) ◽  
pp. 776 ◽  
Author(s):  
DF Dowling
Keyword(s):  
Bos Taurus ◽  
Bos Indicus ◽  
Sweat Glands ◽  
Skin Thickness ◽  
Hot Environment ◽  
Early Maturing ◽  
The Mean ◽  
Critical Characteristics ◽  
Thick Skin ◽  
Active Sweat Glands

The mean total skin thicknesses (mm) for the breeds sampled were: Devon 8.15, Hereford 6.7, Zebu cross 6.43, Australian Illawarra Shorthorn 6.23, Friesian 6.0, Zebu 5.77, Aberdeen Angus 5.75, Shorthorn 5.69, and Jersey 5.46. The early maturing Shorthorn (Bos taurus L.) and the Zebu (Bos indicus L.) differed significantly in the depth of the papillary and reticular layers, and in the relative thickness of these skin layers. The mean thickness for the papillary layer; was 0.98 mm in the Zebu, 1.40 mm in the Zebu cross, and 1.70 mm in the Shorthorn. Thus the larger, more active sweat glands of the Zebu are more superficial. The corresponding reticular layer averaged 4.45 mm in the Zebu, 4.5 mm in the Zebu cross, and 4.08 mm in the Shorthorn. The thickness of the papillary layer relative to the total skin thickness was 18.3, 23.7, and 29.3 per cent., for the Zebu, Zebu cross, and Shorthorn respectively. The Zebu and the Jersey have relatively thin skins. Therefore a thick skin is not essential for adaptability to a hot environment. Inherent differences in the function of the follicles and the glands of the papillary layer may be critical characteristics for heat tolerance.

scholarly journals Effect of hormonal growth promotants on palatability and carcass traits of various muscles from steer and heifer carcasses from a Bos indicus - Bos taurus composite cross

2008 ◽  
Vol 48 (11) ◽  
pp. 1415 ◽  
Author(s):  
R. Watson ◽  
R. Polkinghorne ◽  
A. Gee ◽  
M. Porter ◽  
J. M. Thompson ◽  
...  
Keyword(s):  
Bos Taurus ◽  
Vastus Lateralis ◽  
Carcass Traits ◽  
Bos Indicus ◽  
Rectus Femoris ◽  
Biceps Femoris ◽  
Cooking Methods ◽  
Triceps Brachii ◽  
The Mean ◽  
Psoas Major

The effect of several different hormonal growth promotant (HGP) implant strategies on the palatability and carcass traits of different muscles in beef carcasses was investigated using samples from heifer and steer carcasses from a Bos indicus composite breed. In experiment 1, there were seven different implant strategies evaluated in heifers that were given different combinations of up to three implants (implanted at weaning, during backgrounding and at feedlot entry). A total of 112 heifers were slaughtered and 11 muscles or portions were collected from both sides [Mm. adductor femoris, gracilus, semimembranosus, longissimus dorsi lumborum, triceps brachii caput longum, semispinalis capitis, serratus ventralis cervicis, spinalis dorsi, biceps femoris (syn. gluteobiceps), tensor fasciae latae, gluteus medius (both the ‘D’ and the ‘eye’ portions) rectus femoris, vastus intermedius, vastus lateralis and vastus medialis]. These muscles were used to prepare a total of 1030 sensory samples which were aged for either 7 or 21 days and frozen. Thawed samples were cooked using different cooking methods (grill, roast and stir frying) before being evaluated by a consumer taste panel that scored samples for tenderness, juiciness, like flavour and overall liking. Experiment 2 used the steer portion from the same calving, which were treated to a similar array of HGP strategies, except that they were given up to four implants between weaning and slaughter at ~3 years of age. In experiment 2, there was a total of 12 different HGP implant strategies tested. At boning, three muscles (Mm. psoas major, longisimuss dorsi thoracis and lumborum portions) were collected from each of 79 carcasses with a total of 237 steak samples that consumers tested as grilled steaks. For both experiments, the mean of the HGP implant strategies resulted in increased ossification scores (P < 0.05) and decreased marbling scores (P < 0.05) compared with the controls, with the effect on ossification being much larger in the older steer groups. In both experiments, the different HGP strategies decreased (P < 0.05) all sensory scores compared with the controls, for all cooking method and muscle combinations. In experiment 1, there was no interaction between the mean HGP effect and muscle (P > 0.05), and aging rates differed among the muscles (P < 0.05). In experiment 2, there was a significant (P < 0.05) muscle × HGP treatment interaction, with a decrease in tenderness score due to HGP implant strategies in the M. longisimuss thoracis and lumborum portions, compared with no significant effect in the M. psoas major. For both experiments, there were no significant differences among the different implantation strategies on sensory scores (P > 0.05).

Evaluation of Bos indicus and Bos taurus straightbreds and crosses. II. Post-weaning growth, puberty, and pelvic size of heifers

1994 ◽  
Vol 45 (4) ◽  
pp. 795 ◽  
Author(s):  
H Hearnshaw ◽  
PF Arthur ◽  
R Barlow ◽  
PJ Kohun ◽  
RE Darnell
Keyword(s):  
Body Condition ◽  
Bos Taurus ◽  
Body Condition Score ◽  
Bos Indicus ◽  
The Other ◽  
South Wales ◽  
Condition Score ◽  
Medium Quality ◽  
The Mean ◽  
Pelvic Size

Post-weaning growth and body condition, puberty and pelvic size of 197 heifers comprising straightbred Hereford (HxH) and Brahman (BxB), first-cross (BxH) and back-cross (HxBH and BxBH) heifers were evaluated. The heifers were born over a 3 year period, and grazed improved and semi-improved pastures following weaning at Grafton, New South Wales. Prior to weaning, heifers had been reared by dams on three pasture systems (high, medium and low quality pastures). Heifers from low quality pre-weaning pasture had higher (P < 0.05) post-weaning liveweight gain than those from high and medium quality pastures. BxH heifers gained 71 g/day more (P < 0.05) than the mean gain of their contemporaries of the other genotypes, whose gains were similar, from weaning to either 26 or to 30 months of age. Liveweight at all ages was influenced by genotype x pre-weaning pasture system interaction. At 30 months of age, BxH heifers from high and medium pre-weaning pastures were the heaviest. At the same age, but from low quality pre-weaning pasture, heifers with crossbred dams (HxBH and BxBH) were the heaviest. Wither height depended significantly (P < 0.05) on the proportion of Bos indicus genes, increasing from 113.8 cm in the HxH heifers to 124.4 cm in the BxB heifers at 30 months of age. BxH heifers had a higher (P < 0.05) body condition score than their contemporaries of the other genotypes, which were in similar condition, at 26 and 30 months of age. On average (across pre-weaning pasture system), 9% of BxB heifers had reached puberty by 22 months of age compared to 62, 95, 82 and 64% (s.e.= 9) for HxH, HxBH, BxH and BxBH heifers respectively. No significant genotype differences were obtained in the height, width and size of the pelvic opening of the heifers, measured just prior to the beginning of the mating season at 26 months of age.

Comparative drought resistance of Bos indicus and Bos taurus crossbred herds in central Queensland. 2. Relative mortality rates, calf birth weights, and weights and weight changes of breeding cows

1973 ◽  
Vol 13 (61) ◽  
pp. 117 ◽  
Author(s):  
JE Frisch
Keyword(s):  
Weight Loss ◽  
Birth Weight ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Mortality Rates ◽  
Weight Changes ◽  
Method Of Least Squares ◽  
The Mean ◽  
Mature Weight

The mortality rates, weight changes and associated effects of a. draught in 1969 were observed in a herd of Shorthorn x Hereford (SH), Brahman x SH (BX) and Africander x SH (AX) crossbred cows and small herds of purebred Brahman and Africander cows at 'Belmont', Queensland. About half of the cows calved over a two month period from mid-October 1969. All the cows were weighed in February 1968, February and October 1969 and in January 1970 and the data from the crossbreds analysed by the method of least squares. The weights and weight changes of both the calving and non-calving groups followed a similar pattern though the weight changes of the non-calving group were of greater magnitude. The weights showed that the three crossbreds reached the same mature weight but at different rates. The SH cows reached mature weight least rapidly, had the highest mean weight loss during the drought and had the lowest mean gains after the season broke. Weight changes both during and after the drought were however dependent on lactational status in February 1969. The mean weight loss of cows that weaned a calf in 1969 (wet) was similar for all breeds. However, the mean loss of the dry SH cows was significantly greater than that of the dry BX and AX cows. Previously wet cows exhibited compensatory gains after calving but the gain of the wet SH cows was the lowest of the crossbred means. The mean birth weight of the SH calves was reduced below the long term mean by about 4 kg but birthweights of BX and AX calves were similar to those in other years. During the drought the purebred Brahmans lost the least and the purebred Africanders lost the most weight of all breeds. However, the nature of the data precludes any strict comparisons from being drawn. Mortality rates of breeding cows were recorded from 1960 to 1969. Rates were generally highest for the SH, particularly in the drought years of 1965 and 1969. Some reasons are advanced which may explain the differences in performance of the breed types.

179 COMPARISON OF OOCYTE AND EMBRYO PRODUCTION AMONG BOS TAURUS, BOS INDICUS, AND INDICUS-TAURUS DONOR COWS

2010 ◽  
Vol 22 (1) ◽  
pp. 248 ◽  
Author(s):  
J. H. F. Pontes ◽  
K. C. F. Silva ◽  
A. C. Basso ◽  
C. R. Ferreira ◽  
G. M. G. Santos ◽  
...  
Keyword(s):  
High Efficiency ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Cumulus Cells ◽  
Holstein Cows ◽  
Embryo Production ◽  
Total N ◽  
The Mean ◽  
Donor Cows

In recent years, Brazil has become the leading country in the world for the number of embryos produced in vitro (Thibier M 2009 IETS Embryo Transfer Newsletter 22, 12-19). This is partly due to the large numbers of Bos indicus animals in Brazil, making up about 80% of the total cattle. The mean oocyte production per ultrasound-guided follicular aspiration from Bos indicus is higher than those for European breeds (Pontes JHF et al. 2009 Theriogenology 71, 690-697). In the present study, we analyzed 5407 ovum pick ups (OPU) and compared the average production of total (n = 90,086) and viable (n = 64,826) oocytes and the number of embryos produced in vitro from Gir (Bos taurus indicus), Holstein (Bos taurus taurus), 1/4 Holstein × 3/4 Gir, and 1/2 Holstein-Gir crossbreed cows. To obtain oocytes, OPU was repeated from 4 to 7 times (mean = 5.7 ± 2.4) in each donor cow aged from 3 to 7 years (mean = 5.0 ± 2.3) during a 12-mo period. COCs (n = 90,086) obtained were classified according to the presence of cumulus cells and the oocyte cytoplasm aspect (homogeneous or heterogeneous/fragmented). The viable oocytes (n = 64,826) were in vitro matured for 24 h at 38.8°C in an atmosphere of 5% CO2 in air. Since this was a commercial programm, frozen sexed semen (2 × 106 mL-1) from Gir (n = 8) or Holstein (n = 7) sires previously tested for high efficiency was used for IVF. Fertilization was carried out (18-20 h) and the presumed embryos were cultured for 7 days in the same conditions as were used for IVM. Data were analyzed by ANOVA. On average, 16.7 ± 6.2 oocytes were obtained per OPU/IVF procedure and 71.96% were considered viable. The mean numbers of total oocytes per OPU/IVF procedure were 17.1 ± 4.4 for Gir cows (n = 617), 11.4 ± 3.9 for Holstein cows (n = 180), 20.4 ± 5.8 for 1/4 Holstein × 3/4 Gir (n = 44), and 31.4 ± 5.6 for 1/2 Holstein-Gir crossbreed females (n = 37, P < 0.01). The mean numbers of viable oocytes per OPU/IVF procedure were 12.1 ± 3.8 for Gir cows, 8.0 ± 2.6 for Holstein cows, 16.8, ± 5.0 for 1/4 Holstein × 3/4 Gir, and 24.3 ± 4.7 for 1/2 Holstein-Gir crossbreed females (P < 0.01). The average number of embryos produced by OPU/IVF were 3.2 (n = 12,243/3378) for Gir cows, 2.2 (n = 2426/1138) for Holstein cows, 3.9 (n = 1033/267) for 1/4 Holstein × 3/4 Gir, and 5.5 (n = 1222/224) for 1/2 Holstein-Gir. The average number of embryos produced per IVF session from 1/2 taurus × indicus donor cows was greater (P < 0.01) than from Bos indicus cows. The number of recoverable and viable oocytes and the number of embryos produced in vitro from Bos indicus donors were higher than from Bos taurus females. Therefore, the highest oocyte yield and the greatest embryo production were obtained from 1/2 taurus × indicus females. This work was supported by In Vitro Brasil.

scholarly journals Utilization of low-quality roughage byBos taurusandBos indicuscattle

1985 ◽  
Vol 53 (3) ◽  
pp. 649-656 ◽  
Author(s):  
R. A. Hunter ◽  
B. D. Siebert
Keyword(s):  
Dry Matter ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Dietary Factors ◽  
Plasma Urea ◽  
Mean Retention Time ◽  
Digitaria Decumbens ◽  
Breed Difference ◽  
Significant Difference ◽  
The Mean

1. In a number of experiments voluntary food intake of three low-quality roughages, either alone or supplemented with rumen-degradable nitrogen and sulphur and minerals, was measured in Brahman (Bos indicus) and Hereford (Bos taurus) steers. The chaffed hays were Spear grass (Heteropogon conform) (6.2 g N/kg organic matter (OM)), Pangola grass (Digitaria decumbens) (7.9 g N/kg OM), and Pangola grass (12.0 g N/kg OM). Rumen characteristics relating to rate of fluid outflow from the rumen were also determined.2. There was no significant difference between breeds in the dry-matter intakes of the unsupplemented diets which ranged from 11.3 to 17.8 g/kg body-weight (BW) by Herefords and from 11.8 to 16.1 g/kg BW by Brahmans.3. Supplementation of Spear grass with N and S significantly (P < 0.05) increased intake by Herefords (24%) but not by Brahmans. When the lower-N Pangola grass was supplemented there was a significant increase in intake by both breeds with the magnitude of the response in Herefords (42%) (P < 0.001) being greater than that in Brahmans (15%) (P < 0.05). The intakes of both the supplemented Spear grass and the lower-N Pangola diets were significantly (P < 0.05) greater by Herefords than Brahmans. There was no breed difference in intake when the higher-N Pangola grass was supplemented. Both breeds recorded an 8% intake response to supplementation, although the increase was only significant (P < 0.05) in Herefords.4. The mean retention time of fluid in the rumen on the unsupplemented Pangola grass diet of lower N content was 12.7 h in Brahmans compared with 17.5 h in Herefords (P < 0.01). When the higher-N Pangola was fed, both alone and supplemented, the mean retention times were similar on both diets (10.5 and 9.9 h for Herefords; 9.5 and 8.1 h for Brahmans for unsupplemented and supplemented diets respectively).5. Plasma urea concentrations were higher in Brahmans than in Herefords on all diets. Rumen ammonia concentrations were significantly (P < 0.001) higher in Brahmans than Herefords when the lower-N Pangola grass diet was unsupplemented.6. The intakes and the variable intake responses to supplementation between breeds and diets are discussed in relation to a number of animal and dietary factors.

Some skin characters in five breeds of European (Bos taurus) dairy cattle

1963 ◽  
Vol 14 (2) ◽  
pp. 294 ◽  
Author(s):  
T Nay ◽  
RH Hayman
Keyword(s):  
Dairy Cattle ◽  
Layer Thickness ◽  
Sweat Gland ◽  
Bos Taurus ◽  
Unit Area ◽  
Diameter Ratio ◽  
Sweat Glands ◽  
Skin Thickness ◽  
Layer Depth ◽  
Gland Volume

Observations were made of a number of skin characters in five breeds of European (Bos taurus L.) dairy cattle. Skin samples were taken from the cattle in January and July. There were differences between breeds in sweat gland volume and length! diameter ratio, in skin and papillary layer thickness, in the ratio skin thickness/papillary layer thickness, and in the degree of shrinkage in transverse sections cut from the papillary layer. There were no differences between breeds in density of follicle population (and hence sweat glands) per unit area of skin. Sweat gland volume, skin thickness, and papillary layer thickness were larger in winter than in summer, but there were no such differences for sweat gland length/ diameter ratio, the ratio skin thickness/papillary layer thickness, and follicle population density. The only significant overall correlations between characters were those between sweat gland volume and sweat gland length/diameter ratio, and sweat gland volume and papillary layer depth.

The effect of supplements of formaldehyde-treated casein on the partitioning of nutrients between cow and calf in lactating Bos indicus × Bos taurus heifers fed a roughage diet

1988 ◽  
Vol 39 (6) ◽  
pp. 1151 ◽  
Author(s):  
RA Hunter ◽  
T Magner
Keyword(s):  
Growth Hormone ◽  
Milk Yield ◽  
Plasma Insulin ◽  
Bos Taurus ◽  
Physiological State ◽  
Bos Indicus ◽  
Plasma Insulin Concentration ◽  
The Mean ◽  
Milk Solids ◽  
Negative Growth

The effect of a supplement of formaldehyde-treated casein on partition of nutrients and productivity of Bos indicus x Bos taurus (50% x 50%) first-calf heifers was studied. Sixteen pregnant heifers were fed a long-chopped roughage diet (13 g N/kg organic matter) ad lib. for approximately 3 weeks before calving and for 16 weeks after calving. Half the animals were supplemented with formaldehyde-treated casein (300 g per day). There were also 8 non-pregnant, non-lactating controls, half of which were supplemented with formaldehyde-treated casein. Supplementation had no significant effect on intake, irrespective of the physiological state of the heifers. There was a significant (P < 0.05) positive multiple regression between peak intake during lactation and the weight change of both heifer and calf in the first 8 weeks of lactation. Milk yield was not significantly affected by supplementation for the first 8 weeks. In the second half of lactation supplemented heifers produced significantly (P < 0.05) less milk, but not less milk solids, than unsupplemented heifers. During the latter half of lactation there was a highly significant (P < 0.001) positive relationship between milk yield and lactose secretion. The mean (� s.e.m.) length of the period of anoestrus after calving was 17 � 2.5 and 12 � 1.7 weeks for unsupplemented and supplemented heifers respectively. The length of the period of anoestrus was positively related to milk production (P < 0.01) and peak intake during lactation (P < 0.05). Supplemented lactating heifers had significantly (P < 0.05) higher plasma insulin concentrations and significantly (P < 0.01) lower plasma growth hormone concentrations than unsupplemented lactating heifers. In supplemented heifers in the second 8 weeks of lactation plasma insulin concentration was significantly (P < 0.01) negatively correlated with milk yield and yield of milk constituents. Supplementation with formaldehyde-treated casein did not increase roughage intake but did affect the partition of nutrients via a positive insulin and negative growth hormone response. Nutrients were preferentially diverted into maternal body growth rather than milk synthesis in the second half of lactation.

scholarly journals A comparison of the excretion rate of endogenous purine derivatives in the urine of Bos indicus and Bos taurus steers

2006 ◽  
Vol 57 (2) ◽  
pp. 173 ◽  
Author(s):  
M. K. Bowen ◽  
D. P. Poppi ◽  
S. R. McLennan ◽  
V. J. Doogan
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Bos Taurus ◽  
Excretion Rate ◽  
Bos Indicus ◽  
Purine Derivatives ◽  
Fasting Period ◽  
Holstein Friesian ◽  
The Mean ◽  
Maintenance Requirements

Estimates of microbial crude protein (MCP) production by ruminants, using a method based on the excretion of purine derivatives in urine, require an estimate of the excretion of endogenous purine derivatives (PD) by the animal. Current methods allocate a single value to all cattle. An experiment was carried out to compare the endogenous PD excretion in Bos taurus and high-content B. indicus (hereafter, B. indicus) cattle. Five Holstein–Friesian (B. taurus) and 5 Brahman (> 75% B. indicus) steers (mean liveweight 326 ± 3.0 kg) were used in a fasting study. Steers were fed a low-quality buffel grass (Cenchrus ciliaris; 59.4 g crude protein/kg dry matter) hay at estimated maintenance requirements for 19 days, after which hay intake was incrementally reduced for 2 days and the steers were fasted for 7 days. The excretion of PD in urine was measured daily for the last 6 days of the fasting period and the mean represented the daily endogenous PD excretion. Excretion of endogenous PD in the urine of B. indicus steers was less than half that of the B. taurus steers (190 µmol/kg W0.75.day v. 414 µmol/kg W0.75.day; combined s.e. 37.2 µmol/kg W0.75.day; P < 0.001). It was concluded that the use of a single value for endogenous PD excretion is inappropriate for use in MCP estimations and that subspecies-specific values would improve precision.

The rate of cutaneous evaporation in some tropical and temperate breeds of cattle in Nigeria

1975 ◽  
Vol 20 (1) ◽  
pp. 63-68 ◽  
Author(s):  
S. F. Amakiri ◽  
R. Mordi
Keyword(s):  
Evaporation Rate ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Sweat Glands ◽  
Cattle Breeds ◽  
Lateral Thigh ◽  
White Fulani ◽  
Rate Of Evaporation ◽  
Cutaneous Evaporation

SUMMARYThe rate of cutaneous evaporation was highest in the White Fulani (Bos indicus) followed by the N'Dama and German Friesian (Bos taunts). The lowest rate of evaporation was recorded in the Muturu (Bos taurus brachyceros). In all breeds, the rate at 15.00 hr was significantly higher than at 18.00 hr.For the sites sampled, evaporation rate was highest on the hump and mid-side, followed by the neck and lateral thigh and lowest on the dewlap and navel flap.The possible correlation of these results with the size and distribution of the sweat glands on various sites of different cattle breeds is discussed.

BeefSpecs fat calculator to assist decision making to increase compliance rates with beef carcass specifications: evaluation of inputs and outputs

2014 ◽  
Vol 54 (12) ◽  
pp. 2011 ◽  
Author(s):  
M. J. McPhee ◽  
B. J. Walmsley ◽  
D. G. Mayer ◽  
V. H. Oddy
Keyword(s):  
Sensitivity Analysis ◽  
Mean Square Error ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Mean Square ◽  
Beef Industry ◽  
Factorial Matrix ◽  
The Mean ◽  
Input Variables ◽  
Inputs And Outputs

This study evaluated the BeefSpecs fat calculator, a decision-support system developed to assist the beef industry to increase compliance rates with carcass specifications (weight and fat specifications). A challenge to the BeefSpecs calculator and a sensitivity analysis were used to evaluate the inputs and outputs of BeefSpecs. Five industry datasets (n = 80, 97, 68, 25, and 13 for Datasets 1–5, respectively) of Bos taurus, Bos indicus, and Bos taurus × Bos indicus breeds for steers and heifers were collated to challenge BeefSpecs, and a nine-way factorial matrix (n = 57 600) of input variables was created for the sensitivity analysis. There were no significant (P > 0.05) differences in the mean bias between observed and predicted values in any of the datasets but there were significant (P < 0.01) differences in the unity of slope for Datasets 2, 3, and 5. The root-mean-square error was 1.72, 2.61, 2.87, 2.68, and 2.00 mm for Datasets 1–5. The decomposition of the mean-square error of prediction indicated that most of the error contained in the predictions of all models was of a random nature (94%, 85%, 85%, 95% for Datasets 1–4), except in Dataset 5, which had a 47% proportion of error in the slope component. All datasets indicated little bias (0.13%, 12.19%, 12.69%, 0.60%, and 0.12% for Datasets 1–5) in the model predictions. An analysis of variance with the nine-way factorial matrix on the predicted output of final P8 fat was conducted for the sensitivity analysis. A significant (P < 0.01) four-way interaction of days on feed × frame score × initial liveweight × sex was detected. Final P8 fat was sensitive to measurement error in the inputs of frame score when animals had longer feeding periods (e.g. 180 days) and to initial P8 fat when animals had lower initial liveweights (e.g. 200 kg) and higher frame scores (e.g. 7). For each unit of error in estimating frame score, BeefSpecs predicts final P8 with an error of up to 2.3 mm in heifers and up to 1.7 mm in steers. Error in the estimation of initial P8 fat of 2 mm will result in an error of up to 3 mm in the prediction of final P8 fat. The sensitivity analysis of BeefSpecs input variables (frame score and initial P8 fat) on the prediction of final P8 fat indicates that increasing the accuracy of estimating frame score and P8 fat is an issue that needs addressing.

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