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Woody rangelands are important forage resources for grazing goats in the Mediterranean basin. Goats are well adapted in these heterogeneous and complex ecosystems due to their particular anatomic characteristics, metabolic efficiency and browsing ability. However, the mechanism of grazing behavior and forage selection in goats is quite complex and depends on several factors. The present study deals with the seasonal changes of chemical composition in the selected forages and ingested diets as well as their effects on milk yield and composition of goats grazing in a Mediterranean woody rangeland. Hand plucked forage samples similar to those consumed by the goats were collected for chemical analysis. The nutritive value of consumed forages, in combination with the different feeding and grazing system per trial period, influenced milk quality and performance. The replacement of feed supplementation with an increase of the contribution of grazing in the rangeland could maintain the milk yield and quality at the late stage of lactation. In addition, this paper focuses on the influence of the chemical composition of selected forages on the diet selection of goats using a modeling approach. The model showed a high interpretative accuracy and explanatory value (R2 = 0.923) and was able to distinguish the goats' most important criteria for selecting among the forage plant species in relation to several factors. The results indicate that the dietary preferences of goats were influenced, not only by the seasonality of nutritive value and availability of forages in the rangeland, but also by the plant origin of each nutrient source. The selection of Quercus frainetto was highly correlated with its NDF content. Herbaceous species, Cistus creticus and other woody species were mainly selected due to their CP content. The ADL content seemed to have the lowest influence of all nutritive variables on the selection among groups of plant species. The modeling approach, apart from the understanding of grazing behavior of goats, offers additional information that can be useful to the shepherds in order to manage more effectively the feeding and grazing system of their goat's flock.

Sheep herds are a significant capital of dairy industry in Greece, but as dairy farming becomes more complex and intense the need to provide assistance to dairy producers on milk quality is critical. In this study, the quality of raw milk produced in sheep farms of NE Greece was surveyed and the role of various factors was explored. In total, 21 dairy ewe's farms from the regions of Xanthi and Evros, in the north-eastern Greece were monitored. Milk samples were sampled after the morning milking every 15 days throughout the dairy period (March-June). For the study, a questionnaire was also filled by personal interview with the owners in order to collect information about herd characteristics, health status, handling practices etc. From each farm, air was also sampled for microbiological analysis. Milk samples were examined for chemical components: fat content, protein, lactose, non-fat dry matter (NFDM) and somatic cells count (SCC). Microbiological examination involved the estimation of Total Bacterial Counts (TBC), coliform count (CC), Staphylococcus aureus, Streptococcus sp., and preliminary incubation count (PIC). The possible correlation among different bacterial species and their interaction with SCC and chemical components of milk was also considered. It was examined whether farm management practices could influence the hygiene and the quality of milk. Our results show that as an average TBCs were 5.48 log cfu/ml, SCC: 6.05 log cells/ml, CC: 4.49 log cfu/ml, S. aureus: 3.94 log cfu/ml, Streptococcus sp.: 4.95 log cfu/ml and PIC: 5.7 log cfu/ml. The mean fat, protein, lactose and NFDM were 6.17%, 5.28%, 4.73% and 10.95% respectively. The study revealed significant positive correlation between TBC and PIC (0.825), while SCC was marginally positive correlated with protein and NFDM. No statistically significant correlations observed among SCC with any of the bacterial species. Herd size and farm management practices had considerable influence on SCC and bacterial species.

In situ degradability and in vivo (by difference) digestibility trials were conducted to estimate lower tract residual N digestibility (LTRND) of five protein supplements. Efforts were also made to improve the in situ method of measuring protein degradability. For in situ degradability trials, soybean meal (SBM), corn gluten meal (CGM), cotton seed cake (CSC), wheat bran (WB) and corn gluten feed (CGF) were weighed into Dacron bags and incubated in the rumen of three cannulated Chios ewes. SBM, CGF and WB were degraded significantly, while CGM and CSC were least degraded. Microbial contamination (MC) resulted in a 5.3–28.3% artificially decrease in effective ruminal protein degradation of supplements. Total tract digestibility was measured using five rams in an in vivo, by difference, trial using a 5 × 5 Latin-square design. SBM had higher CP digestibility compared to WB, CGF and CSC, and higher N free extract (NFE) digestibility compared to the other feeds. CGM showed higher CP digestibility compared to WB, CGF or CSC, while CGF had higher organic matter (OM) and crude fibre (CF) digestibility compared to WB. CSC was the protein source with the lowest digestibility of OM, CP and NFE in comparison with the other feeds. LTRND was predicted as 0.928, 0.806, 0.227, 0.540, and 0.498 for SBM, CGM, CSC, WB, and CGF, respectively, or 0.931, 0.803, 0.147, 0.364, and 0.316 when the correction for MC was applied. Lower tract N digestibility could be predicted via a combination of in situ degradability and in vivo apparent digestibility data. This approach yields significant data regarding LTRND estimation of protein supplements, while diminishing animal suffering by avoiding small intestinal fistulation.

The aim of this work was to determine the effect of vacuum level of machine milking on milk yield, milk composition, milking efficiency, somatic cells counts (SCC), and teat end thickness of the Greek mountain breed Boutsiko ewes. Seventy two ewes after a suckling period of 45 ± 5 days were divided into three equal groups of 24 animals for level of milk production, prolificacy and lactation number. The overall experiment lasted 14 weeks. All groups were milked with a pulsation rate of 120/min, pulsator ratio of 50/50, and three vacuum levels of 38, 44 and 50 kPa, respectively, were applied for the three groups. Every two weeks, in a.m. and p.m. milking, measurements were taken for machine milk (MM) and machine stripped milk (MSM), milk composition, SCC, milk emission characteristics (only in a.m. milking) and teat end wall thickness (TEWT) before and after milking. The results have shown that the lower vacuum level of 38 kPa increased ( P P P

Parameters of daily milk yield during the first three lactations of Chios ewes were estimated with random regression models. Data consisted of 42 675 test-day records of 7121 ewes from 75 flocks that had lambed between 1998 and 2000. Models fitted fourth order fixed regressions on Legendre polynomials of the number of days post partum and fourth order random regressions on the individual animal. (Co)variance components were estimated with Gibbs sampling. Lactations were analysed separately. The four eigen values accounted for 0·80 to 0·84, 0·11 to 0·15, 0·04 to 0·05 and about 0·01 of the animal variance, respectively, depending on lactation number. Animal variance estimates, including genetic and, partly, permanent environment effects, were high at the beginning of each lactation and decreased as lactation progressed, suggesting that the animal effect is most important to early daily records. Residual variance was highest in the middle of lactation, suggesting that non-systematic environmental factors play a bigger at that time. Animal correlation estimates between daily yield records ranged from 0·26 to 0·99, were highest for adjacent days and decreased for days further apart. The decline had a different shape in the three lactations and was more evident in the first, suggesting that the three lactations may be biologically distinct traits. Animal correlation estimates between daily and total lactation milk yield ranged from 0·61 to 0·98 and were highest in the middle and lowest towards the end of lactation. Early lactation daily yield had an animal correlation of 0·70 to 0·80 with total lactation milk yield, in all three lactations. Results of this study suggest that daily milk yield records in the early stages of lactation may be useful for selection of ewes with high producing ability and accurate prediction of total lactation milk yield.

Linear models were developed and evaluated for the estimation of daily (24 h) and total lactation milk yield of dairy sheep from single morning (am) or evening (pm) milking records. A total of 22,908 individual test-day milk records of 5110 ewes of the Chios breed, raised in 46 flocks, were used. Depending on the model, different daily milk yield estimates were derived for each ewe, accounting for lactation number, stage of lactation, season of previous lambing and interval between successive milkings. Daily milk yield was also estimated from doubling the single am or pm record. Actual and estimated yields were compared using root mean square errors (RMSEs), mean absolute differences, an accuracy parameter defined as the ratio of the actual yield variance over the sum of the variances of actual yield and absolute difference, and the product moment correlation between estimated and actual yield. Results were validated on independent datasets. Linear models resulted in less biased and more accurate estimates of the daily milk yield than simply doubling the am or pm record. Root mean square errors decreased by 7–37% and the mean absolute difference was reduced by 1–4% of the average daily yield. Higher accuracy and correlation were obtained from linear model application than doubling. Total lactation milk yield was predicted based on actual daily yield and compared to predictions based on estimated daily yield from am or pm records, as well as directly on single milking records. Root mean square errors obtained when daily yield had been estimated with linear models were 26–35% lower compared to doubling the am or pm yield and 0–13% lower compared to estimating the total lactation yield directly from single milking records. Linear model application also resulted in lower mean absolute difference and higher accuracy and correlation than doubling the am or pm record. Recording the yield of a single milking (am or pm) instead of both can benefit milk recording by reducing its cost and increasing farmer participation. In this context, linear models developed in the present study can be used for the accurate estimation of daily (24 h) and total lactation milk yield from single milking records.

An experiment was conducted in order to evaluate the effects of gestational undernutrition of rabbit does on growth, carcass composition and meat quality of the offsprings. Thirty primiparous non lactating rabbit does were artificially inseminated and randomly divided in three treatment groups: Control (C; fed to 100% of maintenance requirements throughout gestation, n = 10), early undernourished (EU; fed to 50% of maintenance requirements during days 7–19 of gestation, n = 10) and late undernourished (LU; fed to 50% of maintenance requirements during days 20-27 of gestation, n = 10). During the 4th week of the gestation period, LU does significantly lost weight compared to C and EU groups (P

Effects of vacuum level, pulsation rate and pulsator ratio on machine milking efficiency in local Greek goats were studied in three separate experiments lasting 12, 10 and 11 weeks in three different years. After weaning (49 days) all goats were milked for 14 days at a vacuum level 44 kPa, a 90-pulsations/min and a 50:50 pulsator ratio (this 2-week interval was considered the familiarization period). In the first experiment, three groups (treatments) of goats were subjected to 70, 90 and 120 pulsations/min at milking. For the second experiment another three groups were milked with a vacuum level of 36, 44 and 52 kPa. For the third and final experiment, three pulsator ratios; 65:35, 50:50, 35:65 were compared in three groups. Results suggest that a faster rate (120 pulsations/min) and a higher vacuum level (52 kPa) decreased the percentages of machine milk (MM; from 60.6 to 55.1% for the rate and from 77.3 to 67.9% for the vacuum) and total machine milk (TMM) while increasing the percentage of machine stripped milk (MSM) and hand stripped milk (HSM; from 17.1 to 20.3% for the rate and from 5.7 to 10.0% for the vacuum). Milking time decreased as vacuum levels increased from 36 to 52 kPa and as pulsator ratios increased from 35:65 to 50:50 and 65:35. The pulsator ratio did not modify the percentage of the above milk fractions (MM, MSM, HSM and TMM) but did increase the average milking rate. Optimum conditions for machine milking of local Greek goats appears to be a vacuum level of 36–44 kPa, a pulsation rate of 70–90 and a pulsator ratio of 65:35.