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The aim of this paper was to study some of the teat characteristics involved in the milking ability of indigenous Greek goats such as the vacuum level of the milking machine that is required for the opening of the teat canal sphincter and the changes in the teat end wall thickness induced by milking. Thirty-six dams (12 of the first, 12 of the second and 12 of the third and subsequent lactations) were used after weaning (60 ± 5 days). Dams were milked twice a day (8:00 and 18:00 h) for 12 weeks in a milking parlour 1 × 12 side by side of Casse type with 6 milking units and a low milk line and air pipeline. The main functional characteristics of milking machine were: vacuum level 44 kPa, pulsation rate 90 pulsations/min and pulsation ratio 50:50. Every 14 days, during morning and evening milking the vacuum level that was required for the opening of the teat sphincter (VOTS) was measured. The measurement of teat end wall thickness (TEWT) was performed before and after milking. The results of this study showed that during the experimental period the mean VOTS was 23.57 ± 0.36 kPa and decreased significantly as the stage of lactation progressed (P< 0.001). The post-milking TEWT was 3.55% higher in comparison with that before milking (P < 0.01). A continuous and significant decrease in teat thickness was observed during the lactation stage (P < 0.001), which suggests a reaction to intramammary pressure and milk quantity in the udder. The TEWT was affected significantly by the parity (P < 0.01). A positive correlation was found between VOTS and TEWT before and after milking (0.4 and 0.36, respectively). It could be said that a lower vacuum level is required for the opening of the teat sphincter of the udder in goats of the indigenous Greek breed. The thicker teat end wall and more resistant sphincter could be less favourable in the machine milking of goats.

Forty male lambs of the mountain Greek breed were used to evaluate the effect of age at slaughter on carcass characteristics and composition. The slaughter of lambs was carried out at the age of 30, 45, 60, 75 and 90 days. The slaughter procedure, carcass dissection and carcass composition were realized according to the standard method of CIHEAM-AGRIMED programme. The results of this work showed that the lambs of different age groups did not differ in dressing percentage significantly. The proportion of muscles showed a tendency of increase with the increasing slaughter age but the differences were not significant. The proportion of total fat in carcass increased with the increasing slaughter age from 20.84 to 23.59% for the age group of 30 and 90 days, respectively (P < 0.05). On the contrary, as the age at slaughter increased, the proportion of bones decreased (P < 0.05). Subcutaneous, intermuscular, perinephric and pelvic fats increased with the slaughter age, but only the subcutaneous fat was influenced significantly (P < 0.05). Among the different commercial cuts proportions of long leg, first 5 ribs and shoulder decreased, while those of last 8 ribs-loin and breast-flank increased (P < 0.05). The overall results suggest that the slaughter age of lambs of the mountain Greek breed should be increased from the present ~45 days to more advanced age of 75 or 90 days in order to improve the farmers' profits without serious negative effects on the quality of carcasses or meat of lambs.

A random sample of 40 goats was used to study the partitioning, yield and composition of milk: 8 of Saanen breed (S), 8 of Damascus breed (D), 8 crossbreds Saanen × Local Greek goat (S × L), 8 backcrosses Saanen × Local Greek goat {(S × L) × S} and 8 crossbreds Saanen × Alpine (S × A). Four dams of each genotype were of the first and four of the second parity. Goats were milked twice daily (8:00, 18:00 h) in a 1 × 12 side by side milking parlour with 6 milking units. Milk yield and milk fractions (machine milk, machine stripped milk and hand stripped milk) were recorded twice daily each 14 days (from 7th-8th to 29th week of lactation). Milk composition was examined once a month separately for morning and afternoon samples. The ponderable mean was used for the calculation of milk fat, protein and lactose percentage. The results of the experiment showed that milk partitioning in purebred and crossbred goats ranged on satisfactory levels (machine milk - MM: morning 69.8-81.6%, afternoon 66.2-77.4%; machine stripping milk - MSM: morning 12.2-19.3%, afternoon 19.2-23.4%; hand stripping milk - HSM: morning 6.1-10.9%, afternoon 5.4-11.9%; total machine milk - TMM: morning 89-94.6%, afternoon 88-94.6%). The effect of breed (crossbred) was found to be significant for all milk fractions (ml and %, P < 0.001 and P < 0.05, respectively). The effect of parity was significant except for MSM (%) and HSM (%). The effect of lactation stage (control day) and the animals was also found to be significant (P < 0.001). The fat percentage of S, D, S × L, S × A and (S × L) × L was 3.82, 5.1, 4.8, 3.88 and 3.95%, respectively (P < 0.001). Protein percentage ranged from 3.1 to 3.6% in the different genotypes (P< 0.001) while lactose percentage was from 4.51 to 4.66%. In conclusion it may be said that imported dairy goat breeds and different crosses with local Greek breed are characterized by good milkability. So the best technique of machine milking is the "routine" milking without applying hand stripping.