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The article focuses on relationship between milk score near udder score and parturition near weaning and effects on Targhee, Polypay, and Rambouillet ewe productivity. Topics discussed include recording of ewe milk production near parturition on subjective scale in flock, heritability of milk score along with genetic correlation with ewe productivity and relationships between milk yield and udder conformation.

Highlights • The plantain-chicory sward has a high nutritional quality. • A plantain-chicory mix can maintain sheep milk production. • Grazing a plantain-chicory mix reduces fat and increases protein in the ewe´s milk. • The plantain-chicory mix improved efficiency of protein utilization. Abstract Fat lamb production systems in humid-temperate regions rely heavily on grass-based permanent swards with a seasonal growth pattern: scarce in winter, copious in spring and slow or nil growth in dry summers. Plantain (Plantago lanceolata L.) and chicory (Cichorium intybus L.) are summer-active, tolerate water deficit and present a high nutritional quality. They start to grow in late winter (especially plantain) and can be grazed in mid-lactation by ewes suckling their lambs. This work compared milk production and quality of suckling ewes grazing a mixture of plantain-chicory (PCH) or a grass-based permanent sward (GBS) by early spring in two consecutive years. Nine Austral ewes (a local meat breed) in their 8th week post-partum were allocated to PCH and GBS treatments with three replications in two consecutive years. After a pre-experimental period, milk production was determined by the oxytocin method. Milk samples were obtained in the second year and analysed for fat, protein, total solids and urea. Pastures were sampled and analysed for nutritional composition. No effects of treatments were detected for milk production (average 1.43 L/d). PCH milk had lower total solids than GBS milk (19.57 vs. 21.80%, P < 0.01), lower fat (6.97 vs. 9.60%, P < 0.01) and lower urea (47.00 vs, 58.22 mg/100 g, P < 0.05), but protein concentration was higher for PCH than GBS milk (5.71 vs 5.18%, P < 0.05). In forage, total ash was higher (P < 0.05) in PCH than GBS (125.8 vs. 89.9 g/kg dry matter, DM), but lower in year 2016 than 2015 (97.9 vs. 117.7 g/kg DM, respectively). Differences (P < 0.05) were found between swards for NDF (PCH: 245.6; GBS: 394.1 g/kg DM) and years (2015: 372.3; 2016: 267.3 g/kg DM). Apparent DM intake was similar (P > 0.05) between years and swards, averaging 2.15 and 1.78 kg/d for PCH and GBS, respectively. It is concluded that plantain and chicory can be grazed by suckling ewes in mid-lactation without detrimental effects on their milk production or composition. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyse milk traits (milk yield from morning milking, and fat, protein and lactose contents) and somatic cell count (SCC) in dairy sheep breeds in Slovakia: Tsigai (TS), Improved Valachian (IV) and Lacaune (LC), and their crosses (IV × LC and TS × LC). Milk performance testing was performed between 2010 and 2013. Mixed model for milk traits included fixed factors: SCC class (low, medium high), lactation number, month in milk, year-month of measurement, genotype, lactation number × month in milk interaction, lactation number × SCC class interaction, and random effects of ewe and residual error. Mixed model for log10SCC (decadic logarithm of SCC) included the same factors except for SCC class and lactation number × SCC class interaction. Instead, covariates of milk yield and milk components were considered. Milk yield and lactose content decreased (P = 0.05 and P = 0.01, respectively), whereas fat and protein contents increased (P = 0.05 and P = 0.01, respectively) with increasing SCC. Similar trends were revealed when relationships between log10SCC and milk yield and milk components were investigated through linear regressions and correlations (however, not all regressions were statistically significant, also correlations between log10SCC and milk yield and between log10SCC and fat content were very weak). To ensure the effectiveness of mastitis control programmes, further research is needed to understand an importance of somatic cells function as an indicator of health status which may affect ewe udder, milk yield and milk components. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the physical and chemical composition of goat milk produced by eight local farms located in the central region of Malaysia. Farms 1 to 4 (F1-SC, F2-SP, F3-SP, F4-SBC) reared Saanen-type goats while farms 5 to 8 (F5-JK, F6-JPEC, F7-JTC, F8-JC), Jamnapari-type goats. The common feedstuffs used in all farms comprised of fresh or silage from Napier grass, feed pellets, and brans while two farms, F5-JK and F6-JPEC supplemented the feeds with soybean-based product. The total solid content, dry matter, and proximate composition of goat milk and feedstuffs from the different farms were determined and the results analysed using principal component analysis. Total solid content of goat milk from the Jamnapari crossbreed had the highest solid content ranging from 11.81% to 17.54% compared to milk from farms with Saanen and Saanen crossbreed (10.95% to 14.63%). Jamnapari-type goats from F5-JK, F6-JPEC, and F8-JC had significantly higher (p < 0.05) milk fat and protein contents (7.36%, 7.14%, and 6.59% fat; 5.08%, 6.19%, and 4.23% protein, respectively) than milk from other farms but, milk produced by Saanen-type goats from F4-SBC contained similar protein content (4.34%) to that from F8-JC. Total ash and carbohydrate contents in milk ranged between 0.67% to 0.86% and 3.26% to 4.71%, respectively, regardless of goat breed. Feeding soybean-based products appear to have a positive influence on milk fat and protein content in Jamnaparitype goats. [ABSTRACT FROM AUTHOR]

The objectives in this experiment were to compare the effects of castor oil, canola oil, or sunflower oil on lactation performance, milk composition, and milk fatty acid (FA) profile in Santa Inês ewes and on growth of lambs. Forty-four ewes (66.9 ± 4.7 kg of initial BW, mean ± SD) were penned individually with their lambs and used in a randomized complete block design with 11 blocks and four diets. The experimental diets were as follows: 1) basal diet without added oil (control), 2) 30 g FA/kg DM of canola oil (CAN), 3) 30 g FA/kg DM of sunflower oil (SUN), and 4) 30 g FA/kg DM of castor oil (CAS). The oils were added to a basal diet containing 50% of roughage. Once a week, from the 2nd to 8th wk of lactation, ewes were separated from their lambs, injected with oxytocin, and mechanically milked to empty the udder. After 3 h, using the same procedure, milk production was recorded, and milk was sampled for composition and FA profile determination. The growth of the lambs was monitored weekly. Ewes fed the control diet had greater (P < 0.05) dry matter intake (DMI) than those fed the oil-supplemented diets. No effect was observed on milk yield and on final BW of lambs. Milk fat and milk total solid concentrations were greater (P < 0.05) with the supply of CAS. Supplementation with CAN and SUN, but not with CAS, reduced (P < 0.05) the sum of FA with 14 or less carbon chains and increased (P < 0.05) the c9-18:1, 18:0 and most of the biohydrogenation intermediates, including the t10-18:1, t11-18:1, and c9,t11-18:2. All oil-supplemented diets reduced (P < 0.05) the content of 16:0 when compared with the control. Milk from ewes fed CAS presented only small proportion of 12-OH,c9-18:1 (0.31% of total FA) but much larger proportions of 12-OH-18:0 (1.58% of total FA) and particularly of 12-oxo-18:0 (2.95 % of total FA), which suggests that 12-OH,c9-18:1 was extensively metabolized in the rumen. Concluding, CAS increased milk fat and modified the milk FA composition by increasing the hydroxy- and oxo-FA. The potential health promoting proprieties and technological advantages of milk enriched with hydroxy- and oxo-FA are not know at present but deserve to be explored. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of milking frequency reduction from twice (TDM) to once (ODM) daily on mammary physiology, activities of all milk enzymes implicated in the plasminogen activating cascade and animal welfare in dairy ewes. Thirty-eight dairy ewes (Chios, n = 22; Karagouniko, n = 16) under the same dietary and management conditions were used in a 14-wk experiment lasting from the 92nd to the 188th day of lactation period. The ewes were distributed in two equal groups of animals per breed. The first 14 days served as an acclimatization period and once per day milking started at the 106th day following parturition and lasted 12 weeks. A significant decline in milk production of ODM ewes was observed compared to that of TDM ewes (−29.2%, P < 0.001 ). Enzymatic activities of plasmin (PL), plasminogen-derived (PG) and plasminogen activator (PA) were significantly increased in the milk of ODM ewes compared to that of TDM. Furthermore, the sum of PL + PG activities was increased in ewes milked once daily and this indicates possible enhanced entrance of plasminogen towards milk. Increased blood lactose was observed in the ODM ewes at the 108th d following parturition, 2 days after the milking frequency reduction was started, a finding indicating that the permeability of the tight junctions was compromised, although the leakiness of tight junctions was a transient phenomenon. Finally, no significant signs of distress were observed in ODM ewes. Thus, ODM treatment does not affect negatively the welfare of dairy ewes. Overall, the adaptation of the ODM practice is not recommended for the Greek farmers despite the apparent improvement of their quality of life. [ABSTRACT FROM AUTHOR]

This study assessed the influence of reducing the crude protein (CP) content (from 190 to 130 g/kg CP/kg) in the supplementary concentrate and time allotment on pasture (TAP) on the milk yield, bodyweight, and the urinary nitrogen (N) and purine derivatives (PD) in lactating Latxa ewes. Animals were reared in a production system that restricted the amount of time that ewes spent on pasture. In mid-April, at the start of the 42 days experiment, 40 dairy Latxa ewes were assigned to one of four groups on the basis of their initial milk yield, days in lactation (DIL), bodyweight (BW), and condition score; thereafter, each group grazed in its own fenced paddock. The experiment was based on a 2 x 2 factorial design that included two CP levels and two pasture grazing regimes: 4 h continuous grazing (CG) in the morning or 2 h grazing in the morning and 2 h in the afternoon (DG). Individual milk yield was recorded three times a week, and time spent grazing and BW was recorded weekly. In the middle (day 15-17; P1) and at the end (day 36-38; P2) of the experiment, urinary spot samples were collected using a catheter. At the end of the experiment, ewes were confined to metabolic cages and urine was collected. CP level of the concentrate was not correlated with time spent grazing; however, the ewes that were permitted access to pasture twice per day spent more time grazing (223 min/day vs 207 min/day, P < 0.01) and were more efficient with their time (56 min/h grazing vs 52 min/h, P < 0.05) than the ewes that were permitted access to pasture once per day. Concentrate CP levels were not correlated with milk yield or composition, although ewes that received the high protein (HP) lost more weight than did those that received the low protein (LP) concentrate. Concentrate CP level and TAP were not correlated with creatinine (CR) excretion rate (mean = 315 µmol/kg LW0.75 s.e. 0.0161). Urea-N was the largest component of urinary-N (68.7 s.e. 2.33%; P > 0.05), and urea-N waste was higher in HP ewes (202.7 mmol/day) than it was in LP ewes (159.5 mmol/day) (s.d. 27.83; P < 0.01). Ewes subjected to the DG regime had significantly (P < 0.01) higher urinary PD excretion (23.6 vs 21.4 mmol/day s.d. 4.01; P < 0.01), and tended (P < 0.1) to excrete less urea-N (175.1 vs 188.3 mmol, s.d. 27.83) than did the CG ewes. A reduction in the CP in the supplementary concentrate led to a reduction in N waste without having a detrimental effect on performance or milk production. In the Basque Country, Spain, dairy sheep production is based on high pasture use. Scarce grass source in the region makes shepherds attempt to balance herbage and forage with concentrates high in protein level to maintain the nutritional requirements of lactating ewes. This study shows a reduction in the protein level of the supplementary concentrate contributed to a reduction in the ration cost and nitrogen waste without a measurable effect on ewe performance or milk yield. [ABSTRACT FROM AUTHOR]

The purpose of this paper was to the revelation of phenotypic correlations of milk production with some morph-productive characters of organism ewe and lamb descendent that influence variability of this production at the Moldavian Karakul ewes. The research was conducted on lactating ewe from flock of sheep of National Institute of Animal Husbandry and Veterinary Medicine from Maximovca village, Anenii Noi district, Republic of Moldova. The ewes milk production was determined by milking control, systematically conducted at every ewe once in 15 days during the whole lactation, according to the Instructions of evaluation of Karakul sheep with improve principles, approved by the Technical and Scientific Ministry of Agriculture and Food. Were investigated correlative connections of the ewes milk production with body weight and skin own qualities (class and type of curls) of the ewe, also with and body weight at birth lamb-descendent and skin qualities (class of evaluation expressed points) in its evaluation marks. It was found, that milk production of Moldovan Karakul ewes is in linear curve relationship with their body weight. This means that with weight gain of ewes up to a certain level (in our case - 60 kg), their milk production is increasing. After reaching the optimum level of body weight, the ewes' milk production tends to decrease. The coefficient value of linear correlation is small and close to zero (rxy = 0.024 - 0.043) but linear curve nature of this relationship is confirmed by the correlation attitude (ηxy = 0.186 - 0.285) which is significant (P < 0.05). The ewes milk production is not in physiological (genotyping) relationships antagonistic qualities of their skin, because have been not detected any significant correlations between skin own qualities (class and type of curls) evaluation marks we have at the moment after ewe birth at the age of lamb and its milk production after calving there of. Between the milk production of ewes-mother and the skin qualities of descendents lambs there is a positive correlation, direct linear and significant (rxy = 0.133 ± 0.062; tr = 2.14; P <0.05). This correlation additive influence on the selection process geared both towards improving milk production and the skin lambs qualities in the flock. Between the lamb body weight at the birth and the ewe milk production, what have been obtained in lactation that following after the birth of this lamb, there is a correlation quite close, directly linear high significance (rxy = 0.460 ± 0.055; tr = 8.36; P <0.001). The existence of positive correlation between these two important morph-productive characters favoring selection efficiency by both characters, obtaining the additive effect in its improvements. In the researched flock, the coefficient of direct linear regression of the milk production depending on lamb body weight at birth have been was Rx/y = 12.20 ± 0.09 kg, what it means, that with increasing of body weight of lambs at birth with 1 kg, the ewes milk production will increase on average by 12.2 kg. [ABSTRACT FROM AUTHOR]

Milking operations represent more than 50% of the work on a dairy ewe farm. The implementation of automatic cluster removers (ACR) is gaining popularity, as it allows the operator to avoid manual cluster detachments, simplifying the milking routines. The aim of this study was to discover the effect on the milking of Manchega ewes over an entire lactation period by using this type of devices, set up with 2 different combinations of milk flow threshold (MF) and delay time (DT) and comparing them with the traditional method using manual cluster removal. During a 15-d pre-experimental period, the animals were milked without ACR and sampling was performed to select 108 ewes and distribute them into 3 groups of similar characteristics according to their parity, milk yield, milking duration, and mammary gland sanitary status. Later, each group was milked for a duration of 4 mo in 3 different conditions: 1 with manual cluster removal, the second setting the ACR at MF 150 g/min and DT 20 s, and the third setting the ACR at MF 200 g/min and DT 10 s. Samplings of milking fraction, milking duration, milk composition, mammary gland sanitary status, teat-end status, and vacuum level in the short milk tubes during milking were performed. The use of ACR limited the vacuum drops in the short milk tubes and the edema in the teat end after milking, although no reduction in the number of new cases of mastitis was observed and the milk composition did not change. Moreover, it was noted that the use of ACR set with MF 150 g/min and DT 20 s was more efficient than the manual cluster removal, as it obtained a similar amount of extracted milk but took less time. Conversely, the use of ACR set with MF 200 g/min and DT 10 s involved a higher reduction in individual milking duration and the milking duration of groups of animals but reduced milk extracted. [ABSTRACT FROM AUTHOR]

Objective. The objective of the current study was to compare two methods to estimate daily milk production in crossbred hair ewes. Materials and methods. Eight multiparous, crossbred (Pelibuey x Katahdin) lactating hair ewes were used in a completely randomized design with repeated measurements, for 56 days. Ewes were fed ad libitum with a diet based on concentrate. Milk production was estimated twice a week for each ewe by both methods, suckled-hand (SH) and weigh-suckle-weigh (WSW) method. Results. Milk production (p>0.05) means were 1031.9±95.6 and 1119.0±95.6 g/day/ewe for SH and WSW method, respectively. Conclusions. No significant differences (p>0.05) were found between methods for milk yield. [ABSTRACT FROM AUTHOR]

The objective of the study was twofold: (i) to quantify the differences in daily milk yield (DMY) and total milk yield (TMY) between lame and non-lame dairy ewes and (ii) to determine the shape of lactation curves around the lameness incident. The overall study was a prospective study of lameness for the surveyed sheep population, with a nested study including the selection of matching controls for each lame ewe separately. Two intensively reared flocks of purebred Chios ewes and a total of 283 ewes were used. Data, including gait assessment and DMY records, were collected on a weekly basis during on-farm visits across the milking period. A general linear model was developed for the calculation of lactation curves of lame and non-lame ewes, whereas one-way ANOVA was used for the comparisons between lame ewes and their controls. Lameness incidence was 12·4 and 16·8% on Farms A and B, respectively. Average DMY in lame ewes was significantly lower (213·8 g, P < 0·001) compared with the rest of the flock, where DMY averaged 1·340 g. The highest DMY reduction in lame ewes was observed during the week 16 of the milking period (P < 0·001), whereas the reduction of DMY, for lame ewes, remained significant at P < 0·001 level from week 8 to week 28 of milking. Comparisons between lame and controls revealed that at the week of lameness diagnosis a significant DMY reduction (P ≤ 0·001) was observed in lame ewes (about 32·5%), which was maximised 1 week later (35·8%, P ≤ 0·001) and continued for several weeks after recovery, resulting in 19·3% lower TMY for lame ewes for the first 210 d of the milking period (P < 0·01). Moreover, at flock level, TMY for non-lame and lame ewes, as calculated by the general linear model, was 318·9 and 268·0 kg, respectively. The results of this study demonstrate evidence of significant financial losses in dairy sheep due to lameness which, however, need to be accurately estimated in further, more detailed, analyses. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the intake, digestibility, milk yield and indicators of the metabolic status of native lactating ewes supplemented under grazing system. In the present study 28 lactating ewes were selected: 14 Morada Nova (MN) and 14 Santa Inês (SI), distributed in a completely randomized experimental design, with a 2x2x2 factorial arrangement of two breeds, two supplementation levels and two experimental periods. Blood samples were collected from lambing to 70 days of lactation, with 14 days interval. Laboratory analyses consisted in determining serum glucose, triglycerides, cholesterol, urea and creatinine. Concentrate intake (g/day) during the lactation differed (P<0.05) between breeds. Total dry matter intake of ewes was affected (P<0.05) by breed and treatment. Morada Nova ewes presented lower intake than SI due to their smaller size. Serum glucose, triglycerides, cholesterol, urea and creatinine differed between breeds (P<0.05) with greater levels in SI ewes compared with MN. Concentrate supplementation did not affect (P>0.05) the serum levels of these metabolites. Indicators of the metabolic status were not affected by concentrate supplementation, which was effective for the maintenance of normal serum concentrations. However, these values differ between breeds within the permissible standards, indicating a high adaptation to postpartum. [ABSTRACT FROM AUTHOR]

Determination of milk yield potential using an accurate method is essential for assessing nutritional requirements, evaluation of genetic potential, lamb growth and survival, management decisions and improving performance traits of sheep flocks. Exogenous oxytocin injection is applied to estimate milk secretion rate in sheep. Oxytocin is a neurohormone produced in the hypothalamo-neurohypophysial system, which is released into the blood in response to teat stimulation. It has a galactopoietic effect and plays an important role in lactation acting on milk ejection via the secretory activity and contraction of myoepithelial cells. One hundred singleton-bearing and rearing Makui breed ewes were assigned into two treatments: group I (hand milking and stripping following the intramuscular injection of 2.5 IU of oxytocin) and group II (hand milking and stripping). The study aimed to examine the effect of exogenous oxytocin injection on milk yield, milk composition and lactation length of ewes during the entire lactation period. Data were recorded at fortnightly intervals from post-partum day 14 onward. Oxytocin treatment group produced significantly more average daily milk yield (562.3 vs. 301.4 g) and total milk yield (93.6 vs. 38.5 kg) compared with non-treated animals (P<0.05). Lactation length was 145.7 days and 115.2 days for the oxytocin and the control group, respectively (P=0.038). Oxytocin injection increased milk peak yield and lactation persistency (P<0.05) while shorter peak time (34.1 vs. 39.2 days) was observed for oxytocin group (P=0.043). Oxytocin administration increased milk fat percentage (6.73 vs. 5.86) in treated compared to control ewes (P=0.029). However, no difference was detected in the percentage of protein and lactose associated to the oxytocin injection (P>0.05). The development of milk ejection inhibition throughout lactation during the exclusively suckling period, followed by hand-stripping, entails the need for oxytocin to sustain mammary cells and lactation persistency in ewes. It further confirms that oxytocin allows overcoming the negative feedback mechanisms exerted on milk ejection, enhancing the intracellular transfer of secretory vesicles and contraction of myoepithelial cells and thereby increasing milk production and lactation length, which is a useful technique to ensure complete alveolar milk let-down and optimum milk withdrawal from the cistern. [ABSTRACT FROM AUTHOR]

The effect of supplementing sheep diets with Saccharomyces cerevisiae Inter Yeast® dried brewer's yeast (Leiber GmbH, Bramsche, Germany) or with a Biolex® Beta-S (Leiber GmbH, Bramsche, Germany) extract containing over 70% β-1,3/1,6-D-glucan was investigated. Experiment 1 was carried out with 120 ewes and 190 lambs. The animals were divided into three groups: I - control; II - fed yeast; and III - fed Biolex. The supplements were administered during a 3-week preparation period for tupping and a 70-day lamb-rearing period. The following reproductive parameters were analysed: fertility, prolificacy, lamb rearing and breeding performance, milk yield and lamb growth rate. Experiment 2 was conducted with 120 ewes divided into two groups: I - control and II - fed yeast during a 3-week preparation period. Fertility and prolificacy were analysed. Significant increases in prolificacy were recorded in sheep administered dried brewer's yeast: 28.51% in experiment 1 and 31.33% in experiment 2. Breeding performance was also higher by 35 %. Both yeast supplements had a stimulating impact on the milk yield of ewes and the growth rate of their offspring. Milk from the experimental ewes, especially in the group fed Biolex, had a substantially higher content of dry matter, mainly fat. The lambs in this group had the highest body weight at the age of 70 days. Finally, however, the production of livestock per mother was highest in the group fed the supplement with Saccharomyces cerevisiae. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyse the effect of stage of lactation on daily milk yield, and milk fat and protein content in Tsigai and Improved Valachian ewes. Breed lactation curves for daily milk yield, and milk fat and protein content were modelled as a sub-model of the three-trait animal model based on repeated test-day records that were collected by the Breeding Services of the Slovak Republic between 1995 and 2010. Data included 188403 (Tsigai) and 352094 (Improved Valachian) ewe's performance records. Pedigree file included 35484 (Tsigai) and 66994 (Improved Valachian) animals with genetic ties to ewes with milk performance data. The fixed part of the model included parity, litter size and stage of lactation. The effect of days in milk (i.e. stage of lactation) was fitted using Ali and Schaeffer lactation curve. The random part of the model included flock-test day effect, direct additive genetic effect, and permanent environmental effect of ewe nested within lactation. Due to limited number of test-day records in the first and the eighth month of lactation and related difficulties in modelling milk traits in these phases of lactation, the lactation curves were plotted between days 30 and 210. During lactation period the daily milk yield curves were decreasing, while milk fat and protein content were increasing. Because of higher changes at the beginning of lactation balanced with higher changes at the end of lactation in Tsigai and smaller changes at the beginning of lactation balanced with smaller changes at the end of lactation in Improved Valachian, 150d milk yield and average milk fat and protein content were almost the same in both breeds. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the performance of the Wood model to describe the characteristics of lactation curves of dairy ewes under organic management in Mexico. In total, 4861 weekly test-day milk yield records from 194 lactations of crossbred dairy ewes were analysed to assess the performance of an empirical model to fit their lactation curve. We used the mathematical model proposed by Wood. The evaluation criteria were the correlation coefficient (r) between the values of total milk yield observed and estimated, the coefficient of determination (R²), and the mean square prediction error (MSPE). In addition, the peak yield (PYest) and time at peak yield (PTest) were calculated. The Wood model showed adequate goodness of fit (r = 0.95, R² = 0.92 and MSPE = 0.024). The Wood model detected that 52.06% of lactation curves had a continuously decreasing shape (atypical curve), probably as a consequence of the characteristic management of the organic system, mainly due to the genotype used and the nutritional management. Residuals were greater for atypical curves than for typical ones, indicating differences in the ability of the Wood model to fit the two types of shapes. In typical curves, the Wood model showed adequate estimates of total milk yield and time at peak yield. The peak yield was underestimated both in typical and atypical curves. The Wood model in atypical curves underestimated the time at peak yield and milk yields in late lactation. The Wood model showed a reasonable fit of lactation curve in dairy sheep in organic systems but presented deficiencies of fit in atypical curves; therefore, estimates should be interpreted carefully. The study was conducted to evaluate the performance of the Wood model to describe the characteristics of lactation curves of dairy ewes under organic management. The Wood model detected that 52.06% of lactation curves had a continuously decreasing shape (atypical curves). A reasonable fit of lactation curve was showed by Wood model, but presented deficiencies of fit in atypical curves. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess variance components and genetic parameters for daily milk yield of Tsigai sheep based on test day records. First, heritability estimates and genetic correlations were estimated using multivariate animal models in which milk yield in individual months of lactation was treated as a different trait. For comparison purposes, univariate animal models with milk yield treated as repeated measures of the same trait were employed. In both analyses, test day records between the second and the seventh month of lactation were considered. The fixed effects were lactation number, litter size and days in milk. All these effects were modelled as linear regressions. The random effects were animal genetic effect and permanent environmental effect of ewe. The effect of flock-year-month of test day measurement was fitted either as a fixed (FYM) or random (fym) effect. The number of test day records in the second, third, fourth, fifth, sixth and the seventh month of lactation was 9,943, 40,422, 43,982, 41,687, 32,158 and 3,878, respectively. In total, 172,070 test day records were included. Milk yield heritabilities in individual months of lactation were estimated between 0.11 and 0.14 when FYM was fitted and between 0.08 and 0.12 when fym was fitted. Variance ratios of permanent environmental effect of ewe were estimated between 0.17 and 0.22 when FYM was fitted and between 0.10 and 0.14 when fym was fitted. The proportion of phenotypic variance explained by fym fitted as a random effect ranged from 0.25 to 0.35. Genetic correlations between test day records of daily milk yield ranged from 0.58 to 0.98 and were higher between adjacent months of lactation. Daily milk yield heritabilities estimated with univariate animal models roughly corresponded with heritability estimates from multivariate models: 0.13 when FYM was fitted and 0.09 when fym was fitted. As a general pattern, phenotypic variances were slightly higher with a random effect of flock-year-month. [ABSTRACT FROM AUTHOR]

In order to achieve the objective, the data pertinent to lifetime traits on 762 Hariana cows, progeny of 23 sires maintained at Government Livestock Farm, Hisar were considered for the prediction of lifetime traits from early lactation traits. The prediction of phenotypic values for Number of lactation completed, Life time milk yield, Production life and Milk yield per day of productive life were obtained. The equation having the combination of first three lactation traits is recommended for the prediction of phenotypic value of lifetime traits in Hariana cows. Generally the peak yield of all lactations contributed maximum to R2 value for all lifetime traits. Therefore, it may be concluded that selection on the basis of peak yield would also improve the lifetime performance. [ABSTRACT FROM AUTHOR]

Abstract: We tested the hypothesis that elevated levels of melatonin in lactating sheep, simulated either by short-day conditions or by melatonin implants, would decrease milk yield while disturbing the rhythm of prolactin (PRL) and growth-hormone (GH) secretion. Eight weeks after lambing, lambs were weaned, and the ewes were subsequently used for milking. The ewes were divided into three groups: (i) long-day control group (LDC, n =20); (ii) long-day melatonin-treated group (LDM, n =20) and (iii) artificial short-day group (ASD, n =20). Milk yields were recorded individually at 10-day intervals from day 57 of lactation. Blood samples were drawn from the sheep every 28 days to monitor the changes in PRL and GH secretion. On each sampling date, blood samples were collected at 20-min intervals over a 6-h period beginning at 12:00p.m. The plasma concentrations of PRL and GH were measured using radioimmunoassay. The longest duration of lactation was found in LDC sheep, and the shortest duration was found in LDM and ASD sheep (p <0.05). The highest milk yield was found in the LDC group. Significantly (p ≤0.01) less milk was obtained from the ASD group. The highest PRL concentration was found during the long-day period (from May to July) in LDC sheep. Prolactin concentration decreased with increasing duration of lactation and decreasing day length. The use of melatonin implants (LDM group) or artificial short-day conditions (ASD group) significantly (p ≤0.01) decreased PRL secretion and reduced milk yield as early as the beginning of milking. Growth-hormone concentrations were significantly (p ≤0.001) higher in LDC ewes than in LDM and ASD ewes. In contrast to the temporal profile of PRL secretion, GH concentrations decreased during the long-day period but increased as lactation progressed and day length shortened. Despite the considerable reduction in GH concentrations, the GH-secretion profile retained its characteristic seasonal rhythm. Therefore, we conclude that exogenous melatonin (from implants or induced by artificial photoperiod manipulation) decreases milk yield primarily through its effect on PRL concentrations in lactating ewes. [Copyright &y& Elsevier]

The objective of this study was to evaluate the effect of milk ejection reflex occurrence before the cluster attachment on teats on milkability parameters and milk composition of ewes. Milk flow data were recorded from 24 ewes of the Tsigaj (TS, n = 12) and Improved Valachian (IV, n = 12) on their 80±15 DIM. The experiment was performed during three successive evening milkings. Ewes were divided into a two groups. During the first milking the first group (6 TS, 6IV) was treated by 5 IU i.m. of oxytocin and the second group by physiological saline 60 seconds before the cluster attachmen V. The application of oxytocin (OT) and saline (SA) in both groups was changed in cross over design on the third evening milking. Milk flow kinetics was recorded individually using four electronic jars collecting the milk during milking. Milk samples for composition analysis were taken after milking of ewe. There were no differences between two treatments when total milk, machine milk and stripped milk yield were compared though not significantly the data were higher at OT. OT significantly increased maximal milk flow rate (OT vs. SA: 0.930 vs. 0.628 1.min-1) (p<0.001), milk yield in the thirty (OT vs. SA: 0.117 vs. 0.072 1) (p<0.001) and sixty second of milking (OT vs. SA: 0.136 vs. 0.106 1) (p<0.05) and reduced milking time from 50.63 s to 31.54 s (p<0.01). Statistically significant difference (p<0.05) was also observed at a higher fat content (OT vs. SA: 8.977 vs. 8.484 %). In conclusion, the milk ejection reflex occurrence before milking has a high impact on the milkability and the fat content in milk. [ABSTRACT FROM AUTHOR]

Abstract: In a system based on a test-day alternate recording, a total of 1,227,949 test-day records for somatic cell counts (SCC) and milk yield obtained throughout 12 years (1998–2009) from 196,496 ewes in 156 Manchega flocks belonging to the National Association of Manchega Breeders (AGRAMA, Spain) were used to study the environmental variations of the SCC and its relationship with milk yield. Two subsets containing test-day SCC and milk yield data were also analyzed: SCC≤300×103 cells/ml, and SCC>300×103 cells/ml. Analysis of variance showed significant effects for the ewe, season, age of ewe, lactation stage, number of lambs born, milking shift, and for the flock×year random effect on variables studied. Average values obtained for somatic cell score (SCS) and milk yield were 4.09 and 1156ml/d, respectively. The SCS increased 7.6% through lactation and was highest in winter. The age of ewe effect was highly significant for SCS and milk yield, both increasing with the age, even for the group of ewes with a SCC≤300×103 cells/ml. Twin-birth ewes showed higher SCS (5.0%) and milk yield (9.8%) than single-birth ewes. SCS for p.m. milking was significantly higher than for the a.m. milking. Phenotypic correlation between milk yield and SCS was negative (−0.09), which reflects the reduction in the production ability of ewes with higher SCS. Average differences in milk yield between test-day subsets studied were 11.8%; the greatest differences were in autumn (14.5%) and the lowest in spring (9.8%). Differences in milk yield between the ewes with SCC≤300×103 cells/ml and ewes with SCC>300×103 cells/ml also increased through lactation. Thus, in the first test-day record differences in milk yield reached 5.4%, and the difference increased up to 11.8% in the 4th test-day record. Our results suggest that it seems necessary to take into account the effect of non-infectious factors to interpret the SCC results of recording systems. [Copyright &y& Elsevier]

The study was conducted from April to July on pastures located at different altitudes and of different sward composition during the milking period of Srednostaroplaninska and Tetevenska sheep. Morning bulk milk was sampled for analysis monthly between April and end of July. The purpose of the study was to establish the milk yield and to investigate the chemical composition of sheep milk obtained from Srednostaroplaninska and Tetevenska breeds reared on pastures at a different altitude and with different sward composition. The Tetevenska breed had a higher daily milk yield and exhibited a high percentage of casein in milk, while the milk from Srednostaroplaninska sheep had a higher content of macro elements - calcium, potassium, magnesium and some trace elements (iron and manganese). The milk fat content, including the percentages of saturated and unsaturated fatty acids in milk obtained from studied breeds, was similar. There was a tendency towards higher percentage of polyunsaturated and long-chain fatty acids in the milk of Srednostaroplaninska sheep, reared on mat grass pastures. Milk casein content was higher in the milk of Tetevenska sheep, as well as the content of non-essential amino acids as compared to Srednostaroplaninska sheep. [ABSTRACT FROM AUTHOR]

Abstract: Objective of the study was to assess udder morphology and milking characteristics of Chios-breed dairy ewes. Moreover, by using Principal Component Analysis, the probability of any correlations between various udder traits was studied. Thirty pure-bred Chios-breed dairy ewes in a commercial flock were assessed for 10 udder traits (6 direct and 4 indirect measurements) during three consecutive lactations. Milk yield (MY) and milking time (MT) were electronically recorded for each ewe on a daily basis. Direct measurements included udder length (UL), udder width (UW), udder height (UH), gland cistern height (CH), teat length (TL) and teat diameter (TD). Indirect measurements included teat placement (TP), udder depth (UD), udder cleft (UC) and degree of suspension of the udder (SU). Data analysis was performed using SPSS 16©. The results showed that mean values for UL, UH and TP increased from first to third lactation; TL and TD did not change, whilst UD and UC decreased. The UH and CH were all negatively correlated with UD and SU (P <0.01) and positively correlated with TP (P <0.01). UW had a significantly negative and positive relationship with UD and UC (P <0.01), respectively. Significant negative correlations were also revealed between TL and TP (P <0.01). Four PCs (‘udder dimensions’, ‘teat’, ‘udder morphology’ and ‘teat and suspension’) were recognized explaining about 76% of the total variance. Effect of lactation number was significant for UL, UH, CH, TP, UD, UC, ‘udder dimensions’ and ‘udder morphology’ variables (P <0.05 to P <0.001). ‘Udder dimension’, ‘teat’ and ‘udder morphology’ were significantly related to MY (P <0.05 to P <0.001). In conclusion, the results provide significant information for udder characteristics of the Chios breed, which is the most popular indigenous Greek breed of sheep. Such information could be used as a basis for genetic improvement of the breed. [Copyright &y& Elsevier]

Feeding conjugated linoleic acid (CLA) in a rumeninert form to dairy ewes has been shown to increase milk production, alter milk composition, and increase the milk fat CLA content. However, few studies have tested ruminally unprotected CLA sources. The objective of this study was to evaluate the effects of an unprotected CLA supplement (29.8% of cis-9,trans-11 and 29.9% of trans-10,cis-12 isomers as methyl esters) on milk yield and composition of dairy ewes. Twenty-four lactating Lacaune ewes were used in a crossover design and received 2 dietary treatments: (1) control: basal diet containing no supplemental lipid and (2) basal diet plus CLA (30 g/d). The CLA supplement was mixed into the concentrate and fed in 2 equal meals after morning and afternoon milkings. Each experimental period consisted of 21 d: 7 d for adaptation and 14 d for data collection. The CLA supplement decreased milk fat content and yield by 31.3 and 38.0%, respectively. Milk yield and secretion of milk lactose and protein were decreased by 8.0, 9.8, and 5.6%, respectively. On the other hand, milk protein content and linear SCC score were 1.8 and 17.7% higher in ewes fed the CLA supplement. The concentration of milk fatty acids originating from de novo synthesis (C16) was increased by 22.6% in ewes fed the CLA supplement. The CLA supplement decreased C14:1/C14:0, C16:1/ C16:0, and C18:1/C18:0 desaturase indexes by 25, 18.7, and 0.1%, respectively, but increased the cis-9,trans-11 CLA/trans-11 C18:1 ratio by 8.6%. The concentrations of trans-10,cis-12 CLA and cis-9,trans-11 CLA in milk fat was 309 and 33.4% higher in ewes fed CLA. Pronounced milk fat depression coupled with the deleterious effects on milk yield, milk SCC, and secretion of all milk solids observed in ewes fed an unprotected CLA supplement is likely to be associated with high doses of trans-10,cis-12 CLA reaching the mammary gland, corroborating previous results obtained with dairy cows. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the reaction of ewes (Improved Valachian, Tsigai and Lacaune breed) to some breeding interventions during machine milking through their milking characteristics. Two treatments were tested. Both treatments were done during two consecutive morning milking in cross over design. First one represented the testing of presence of an unknown person in front of the ewes heads. Second treatment represented omitting of the concentrate food during milking. Control milking in both treatments represented the usual milking process. Ewes were milked twice per day at the milking parlour designed for 24 animals and equipped with 12 standard milking units. The equipment for graduated electronic milk recording in jar was used and the computer was recording the level of milk in jar in the one second intervals. There were evaluated in total of 164 milk flow curves. These curves were divided into four groups: 1 peak (1P), 2 peaks - bimodal curves (2P), plateau I (PLI, peak flow over 0.4 l/min) and plateau II (PLII, peak flow under 0.4 l/min). There was observed higher total milk yield, machine milk yield, milk yield in 30 s and in 60 s in control treatment as compared to presence of an unknown person. This corresponded to higher machine stripping yield and percentage of machine stripping in the group of ewes treated by the presence of an unknown person. No differences in milking characteristics were found in the treatment with omitting of concentrates during milking. Obtained results indicated that milking characteristics in ewes were more affected by presence of unknown person than by omitting of concentrates during milking. [ABSTRACT FROM AUTHOR]

Abstract: This study was conducted to evaluate the effects of natural protection of protein from microbial degradation in the rumen by acacia tannins on digestibility, nitrogen (N) retention and milk production in dairy ewes. An experimental sheep flock grazing rye grass pasture was divided into four groups. Indoor, animals were supplemented with 300g of concentrate, 300g of concentrate+100g Acacia cyanophylla foliage (acacia), 300g of concentrate+200g acacia for C, C1A, C2A groups, respectively, and only 100g of acacia for group A. Digestibility and N balance were measured for animals in metabolic cages fed with cut fresh grass. Acacia tannins interact with concentrate supply and significantly affected digestibility. Higher OM and CP digestibility was observed for C1A and C2A groups in comparison with the A group. Digestibility of OM, NDF and CP was higher for animals supplemented with concentrate than for those not supplemented. N retention increased with ration CP content. Acacia tannins led to a high increase of N retention for C1A and C2A groups compared to C group (10.3 vs. 5.8g/day for animals fed acacia and those not fed acacia, respectively). So, urinary nitrogen excretion decreased from 6.5g/day for C group to 4.5g/day for C1A. Milk yield was the highest for C1A group (555ml/day) and the lowest for A group (500ml/day) whereas it was intermediate for other groups. Milk fat content decreased with groups fed acacia in comparison to groups not fed acacia (7.3 vs. 7.6%). Milk protein content decreased when ewes received acacia and concentrate. [Copyright &y& Elsevier]

The present study investigated the effect of age at first lambing (AFL) on the performance of Lacaune sheep under intensive management conditions. Records from 3088 maiden sheep from one farm, for the period 2005–2010, were classified into four experimental groups: group E (early) ewes with AFL ⩽390 d; group M (middle) with AFL of 391–450 d; group L (late) with AFL of 451–510 d; and group A (aged) with AFL ⩾511 d. The higher the number of lactations, the lower were the yield/lactation and yield/Day in Milk. Ewes from group M up to 450 days old lambed 0·2 times more often and had 0·25 more lactations than the ewes from group L; in addition, the former group lambed 0·5 times more often and had 0·49 more lactations than ewes from group A. Group A had the lowest yield per lifetime; the yield followed the sequence: group E (1032 l) >group M (1051 l) >group L (989 l) > group A (859 l) (P<0·0001). Yield/lactation was affected by AFL during the first three lactations (P<0·05). Group E produced significantly less milk in the first lactation than ewes from groups M, L and A. AFL correlated negatively with the number of lactations in life (r= −0·26; P<0·0001) and with total milk yield (r= −209; P<0·0001). The productive performance between the ewes that reached puberty early (n=404) or late (n=2684) in life were different (P<0·0001) with the early sheep having a lower total milk yield (591 v. 1073 l, P<0·0001). In conclusion, the current study indicates that the optimal AFL for the Lacaune breed under an intensive dairy system is between 390 and 450 d. Ewes with AFL earlier than 390 d or later than 450 d are likely to have a shorter productive life and a lower lifetime milk production. [ABSTRACT FROM AUTHOR]

The effect of feeding pelleted total mixed ration (TMR) containing wheat middlings (WM) from durum wheat (Triticum durum Desf. cv. Appulo) as a corn grain substitute on milk yield and composition performance was measured in Comisana × Leccese crossbred lactating ewes. Forty ewes were divided into 2 equal groups and fed 1 of the 2 experimental diets for 18 wk. The control diet contained 255 g of corn/kg of dry matter (DM) as the main starch source, whereas the experimental diet contained 500 g of WM/kg of DM. To evaluate the in vivo digestibility of pelleted TMR, 4 adult rams were placed in metabolic cages and their individual feces and urine were collected. In the performance trial, ewe milk yield was recorded daily and individual milk samples were analyzed weekly for milk composition and to determine milk renneting parameters. The ewes fed both diets showed similar DM, crude protein, and neutral detergent fiber intakes. Digestibility of DM, organic matter, and crude protein of the 2 TMR was similar, but neutral detergent fiber digestibility was higher in the WM diet. In the milking trial, the WM diet increased milk fat percentage and yield but had no effect on milk yield, protein, lactose, and clotting properties compared with the control diet. Our findings indicate that WM can be fed to lactating ewes as an alternative to more traditional concentrate sources such as corn. Feeding 50% of WM in a lactation diet supported milking performance in a manner similar a corn-based diet. Moreover, the results may be applied in countries where corn cultivation is adversely affected by the high cost of production. [ABSTRACT FROM AUTHOR]

The objectives were to determine the effect of administering recombinant bovine ST (bST) every 14 d on milk yield and milk composition in dairy ewes and to assess the possible effects of treatment on milk yield loss that occurs at lamb weaning. Seventy-two lactating dairy ewes were separated into 4 groups at lambing, and each group received no bST (control) or 40, 80, or 120 mg of bST every 14 d until wk 20 of lactation. During the first 5 wk of lactation, ewes suckled their lambs during the night and were milked once daily (period 1). After weaning, from 6 to 22 wk of lactation, ewes were exclusively milked twice daily (period 2). Actual milk yield, potential milk yield, and milk component percentages were recorded weekly throughout lactation. In period 1, bST-treated groups increased yields of potential milk (P = 0.04) and the corresponding 6% fat-corrected milk (FCM; P = 0.04) but not actual milk yield (P = 0.42) compared with the untreated group. In period 2, treated groups increased potential (P < 0.01) and actual (P < 0.01) milk yields as well as their corresponding 6% FCM (potential, P < 0.01; actual, P < 0.01), in comparison with the untreated group. The group treated with 120 mg of bST every 14 d yielded 39% more actual milk and 44% more 6% FCM than the control group for period 2. At weaning, between the last week of period 1 and the first week of period 2, treated groups showed similar absolute (P = 0.15) and relative (P = 0.33) values for the potential milk losses compared with the control group. Treatments increased (P = 0.04) actual milk fat percentages during period 1, but did not affect the other milk components or somatic cell count. In summary, bST increased potential milk yield throughout lactation and actual milk yield only after weaning in dairy ewes. In dairy ewes, bST was not useful for reducing the milk yield loss that occurred at weaning. [ABSTRACT FROM AUTHOR]

The existence of a relationship between cortisol levels, after an acute stress, and behavioral activities, immunological profile, and production performance in sheep was studied. An initial flock of 30 Comisana ewes was involved in the experiment, and each of the 30 ewes was individually subjected to an isolation test in a novel environment. Subsequently, from the initial flock, 2 groups of 8 Comisana ewes were each retrospectively selected, and the animals were divided, according to their cortisol concentration 10 min after the isolation test, into high cortisol (HC) ewes, having a peak of cortisol concentration >90 ng/mL (average: 119.3 ng/ mL ± 11.8), and low cortisol (LC) ewes having a peak of cortisol concentration <80 ng/mL (average: 52.4 ± 11.8). During the isolation test, the behavior of each animal was video-recorded and behavioral activities were registered. Blood samples were collected before the isolation test, immediately after the test (10 min), and at 60, 120, 300 min, 24 h, and 48 h after the test to evaluate percentages of T-helper (CD4+) and Tcytotoxic (CD8+) cells, CD4+/CD8+ ratio, and IL-1β and IL-6 levels. The ewes were milked for 3 d after the isolation test to determine cortisol levels and IL-1β and IL-6 concentrations in whey. Milk yield was recorded at each milking, and milk samples were analyzed for pH, nutritional parameters, renneting properties, and somatic cell count. During the isolation test, HC ewes exhibited a shorter duration of movement and fewer bleats than LC ewes. The average plasma IL-1β concentration was higher in HC than in LC ewes. The average whey IL-1β and IL-6 concentrations were higher in whey from HC ewes than in LC ewes. A positive correlation emerged between plasma and whey IL-1β concentrations. The average CD4+/CD8+ ratio in blood was lower in HC than in LC ewes. Time from isolation affected the CD4+/CD8+ ratio: at 120 min, the CD4+/ CD8+ ratio increased compared with that at 10 min after isolation and then decreased until 300 min after isolation. On average, ewes with low cortisol concentrations showed higher milk production and lower SCC than ewes with high cortisol concentrations. Results suggest that plasma cortisol concentration is connected to the behavioral response and immune competence of dairy ewes and cytokine concentrations. Both whey IL-1β and IL-6 can be considered reliable indicators of the magnitude of hypothalamic-pituitary-adrenal axis activation. The stress-induced changes in CD4+/CD8+ ratio are critical for controlling disease incidence and planning appropriate vaccination programs. High reactivity of the hypothalamic-pituitary-adrenal axis is also associated with a reduction in milk production and an increased predisposition to develop intramammary inflammatory processes. [ABSTRACT FROM AUTHOR]

To improve the effectiveness of community-based breeding programs for increased milk production, the values of different udder measurements for predicting milk production traits during the milking period were assessed over 3 yr on 273 Awassi ewes. Machine milking of ewes began after weaning, 56 d after parturition, and continued until the milk yield of the ewes was <200 mL/d. Milk yield obtained by hand milking and milk composition were measured weekly, and days in milk, total milk yield, and total yields of protein, fat, and nonfat solids in milk were calculated for each ewe. On d 70 of milking, morphological traits of the whole udder (circumference, width, height, and length), udder cistern (height), and teats (length, width, and position score) were measured. On the same day, the milk yield of ewes was recorded by hand milking. Positive and moderate to strong correlations (r = 0.36 to 0.76) between udder circumference and width, teat width, and milk production traits of total milk yield, and total yields of protein, fat, and nonfat solids were found. However, a more accurate predictor of milk production traits was milk yield on d 70, as higher positive correlations between this variable and the milk production traits were found (r = 0.63 to 0.89). Nine farmers were invited to independently estimate the hand-milked milk yield performance of a sample of 169 ewes (d 15 to 45 of milking) by visually observing each ewe and making a subjective linear score (1 to 5). Their assessments were significantly correlated with milk yield on the day of the observation (r = 0.52), total milk yield (r = 0.50), and days in milk (r = 0.45). Considering the perception details provided by farmers concerning each of the subjective linear scores, it was found that most predictive linear udder measurements of udder circumference and width and teat width identified in this study were implicit in these scores. The predictive ability of the measurements studied have practical implications for community-based breeding programs involving improvement of milk production--not just in Syria, but in other countries in dry areas as well--because it is possible for experienced farmers to visually assess milk production of dairy ewes or take simple udder measurements with predictive value. [ABSTRACT FROM AUTHOR]

The long- and the short-term effects of omitting 2 milkings weekly in early (wk 8 to 14) and mid lactation (wk 15 to 22) were investigated in an experiment conducted with a total of 58 dairy ewes (40 Manchega and 18 Lacaune). Ewes submitted to 2 milking omissions were milked twice daily from Monday to Friday (0800 and 1800 h), and once daily on Saturday and Sunday (1600 and 1400 h, respectively). Individual data were collected for milk yield (weekly), milk composition (biweekly), and somatic cell count (SCC; monthly). Omitting 2 milkings per week in early lactation tended to decrease milk yield in Manchega ewes (-15%), whereas no effects were observed in Lacaune ewes. Averaged milk composition was not modified by milking omissions in either breed. Milking omissions in late lactation did not affect milk yield and milk composition in either breed. The SCC were unaffected by milking omissions in both breeds and in both stages of lactation. A sample of 22 Manchega and 11 Lacaune ewes were used to evaluate the short-term (daily) effects of the 2 milking omissions per week on milk yield and composition, udder health, and tight junction permeability, both in early lactation (wk 12) and in mid lactation (wk 20). Milking omission decreased milk yield, milk fat, and milk lactose contents on the first omission day in both breeds, with losses being more noticeable in early lactation than in mid lactation. Milk protein content and SCC did not vary by effect of the weekend milking omissions. After restoring the twice-daily milking routine on Monday, milk yield showed a compensatory increase that was greater in the large-cisterned than in the small-cisterned ewes, which allowed milk yield to return to Friday values in both breeds. Milk fat content increased during Sunday and Monday, reestablishing Friday values thereafter in both breeds. Weekend milking omissions in early lactation caused tight junction leakiness in both breeds, but mammary epithelia adapted to extended milking intervals when applied successively, recovering their tight state after milking. In mid lactation, the mammary tight junction showed leakiness only in Manchega ewes. In conclusion, 2 milkings per week could be omitted with no negative effects on milk yield, milk composition, and milk SCC values in large-cisterned dairy ewes, as observed in Lacaune and large-cisterned Manchega ewes. Losses in milk yield could be reduced if milking omissions were done from mid lactation in small-cisterned ewes. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the effects and transmission of gastrointestinal nematode infection on milk production sheep system. The study used 66 Pampintra breed ewes during milking and the naturally infected ewes were divided into two groups, the treated group (TG) with levamisole and the untreated group. Researchers also conducted a monthly faecal nematode egg counts and larval differentiation. The study revealed that the TG produces more milk liters and the UG and the TG had more extended machine-milking period length than UG.

The aim of this study is to update the values concerning nutritional components for different sheep breeds: Merinos de Cluj, Ţurcana and Ţigaie. The breed of sheep affected the composition of milk. It was found that protein content of Ţurcana has values between 5.79-7.14%, Ţigaie 5.62-7.0% and Mermos de Cluj 4.84-7,72%. The processing performance of the milk is mainly dependent of protein content (renneting time, rate of formation and consistency of the curd) so the cheese makers are interested to use even Merinos de Cluj milk well known as a wool sheep. The fat content is highest in Ţurcana milk (7.80-12.02%) and lowest in Merinos de Cluj (4.55-9.56%). The research has been done on individual milk samples received from 10 individual sheep. The animals were of second lactation and had been bred in the Cluj County and the analysis has been done in 2007 and 2008, at the beginning and at the end of lactation respectively. [ABSTRACT FROM AUTHOR]

Nine Manchega (0.94 L/d) and 10 Lacaune (2.07 L/d) ewes at the same stage of lactation (90 d in milk) were used to study the interbreed differences in milk yield, mammary morphological traits, and machine-milking ability. Udder traits were measured after 6 h of udder filling before the start of the experiment. Cisternal area by ultrasonography), cisternal milk (by teat cannula drainage), and alveolar milk (by machine milking after an intravenous oxytocin injection) were randomly measured 8 h after milking for 2 wk consecutively either with an intravenous injection of an oxytocin receptor blocking agent (atosiban, AT) or without (control, C) avoid the occurrence of milk letdown before milking. Lacaune ewes had greater udder depth (22.5 ± 0.9 vs. 19.6 ± 0.9 cm) and cistern height (27.1 ± 3.8 vs. 15.6 ± 3.5 mm), whereas Manchega ewes had longer (42.7 ± 1.5 vs. 32.7 ± 1.5 mm) and wider teats (17.4 ± 0.5 vs. 13.9 ± 0.5 mm). Values per half udder for Manchega and Lacaune ewes differed in cisternal area (12.8 ± 0.7 and 23.7 ± 0.6 cm²) and cisternal milk (120 ± 0.6 and 269 ± 0.5 mL), but not in alveolar milk (95 ± 0.5 and 102 ± 0.4 mL), respectively. Cisternal area and cisternal milk were positively correlated (r = 0.79). Ratios between cisternal and alveolar milk were 56:44 and 73:27 for Manchega and Lacaune ewes, respectively. Cisternal milk volumes obtained with the AT or C treatment were similar in Manchega (111 ± 10 vs. 122 ± 8 mL but differed in Lacaune ewes (239 ± 8 vs. 299 ± 8 mL), respectively. Consequently, alveolar milk with AT vs. was similar in Manchega (104 ± 8 vs. 86 ± 7 mL) but different in Lacaune ewes (115 ± 7 vs. 89 ± 7 mL). Results of this experiment confirm the need for the use an oxytocin-blocking agent for accurate evaluation milk contained in the udder of dairy ewes. Moreover, despite the differences in daily milk yield, alveolar milk did not vary between breeds, emphasizing the role of the cisternal more than the alveolar compartment for maximizing daily milk secretion in dairy sheep. [ABSTRACT FROM AUTHOR]

The aim of this research was to enhance the nutritional quality of ewe milk fat by increasing potentially healthy fatty acids (FA) through diet supplementation with unprotected oil rich in linoleic acid, and without detrimental effects on animal performance. Twenty-four ewes were assigned to two high concentrate diets, control or supplemented with 6% sunflower oil (SO), for 4 weeks. No differences between treatments were found in milk production and dry matter intake. Although the SO diet increased milk fat percentage and tended to reduce milk protein concentration, it did not affect milk fat, protein or total solid yield. Most of the modifications in milk FA composition were addressed toward a potentially healthier profile: a decrease in C12:0 to C16:0 and a remarkable increase in the contents of cis-9 trans-11 C18:2 (from 0?94 to 3?60?g/100?g total FA) and trans-11 C18:1 (from 2?23 to 8?61?g/100?g total FA). Furthermore, the levels reached were maintained throughout the period monitored. However, the SO diet increased other transC18:1 isomer percentages, too. The lack of differences between treatments in the in vitroruminal fermentation parameters, studied with batch cultures of rumen microorganisms, would indicate no negative effects on ruminal fermentation. [ABSTRACT FROM AUTHOR]

Abstract: The effect of water restriction on milk yield and composition, feed intake, body weight and blood parameters was evaluated in Comisana sheep reared under intensive condition. The experiment, lasted 40 days, was performed on 26 lactating ewes subdivided into three treatment groups; the control T group received water ad libitum (W-100) and Group 1 (W-80) and Group 2 (W-60) were watered, respectively, with 80 and 60% of the water consumed by the control T group. Water was supplied in the morning once a day while feed twice. Milk quality analysis was performed every 10 days for pH, fat, total protein, lactose and somatic cell content. Serum samples, performed at days 0, 13, 26 and 40, were analyzed for glucose, cholesterol, triglycerides, creatinine, total proteins, albumin, sodium, potassium, calcium and chloride. Compared to W-100, W-60 was significantly different (P <0.05) for body weight and serum potassium levels and showed an increase (P <0.01) in serum concentrations of triglycerides, albumin, total proteins and cholesterol (P <0.05). Total proteins, triglycerides and sodium levels increased (P <0.05) in W-80. Body weight showed a significant difference (P <0.05) only in W-60 if compared to W-100. No significant differences were observed in milk yield, milk composition and feed intake across the treatment groups. [Copyright &y& Elsevier]

Abstract: The aim of this study was to develop an efficient strategy for ration formulation for milking ewes of the Chios breed in Greece. The strategy involved two and three groupings according to production level and challenge feeding using lead factors. Lead factors, that adjust upwards the average production of a flock or a group of ewes, were calculated for the 83rd and the 90th percentile, using 49,237 milk test-day records from 549 flock-test-days, referring to 64 flocks and 97 complete lactations. Lead factors were 1.25 for the single-group, 1.14 and 1.17 for the two-group, and 1.11, 1.07 and 1.15 for the three-group strategy for the 83rd percentile. Regarding the 90th percentile, these were: 1.33 for the single-group, 1.18 and 1.19 for the two-group, and 1.15, 1.09 and 1.16 for the three-group strategy. Analysis of variance was used to assess the influence of several effects on lead factors. Flock-year and mean and standard deviation milk yield were significant (P <0.05) in nearly all cases, leading to calculation of different lead factors for high (>250 kg of milk/ewe/year) and low (<250 kg of milk/ewe/year) producing flocks. Higher producing flocks were associated with somewhat lower than average lead factors, while the opposite was true for lower producing flocks. In order to allow the sufficient expression of the genetic potential of the best ewes and accurately estimate their genetic value under Greek conditions, the 90th percentile strategy can be adopted for the higher producing groups and the 83rd for the lower ones. [Copyright &y& Elsevier]

Abstract: Breeders have always been interested in improving the ewes’ milkability, since the milking is the most time-consuming task of dairy sheep farmers. This work was aimed at studying the evolution during the productive life and the individual variability of milk emission traits at machine milking in sheep. Data were recorded in an experimental flock of 889 Sardinian×Lacaune back-cross ewes, by using an automatic device developed by INRA. The analyzed variables (59,615 records) were total milk yield (TMY, ml), machine milk yield (MMY, ml), stripped milk yield (SMY, ml), machine milking time (MMT, s), latency time (LT, s), maximum (MMF) and average (AMF) milk flow (ml/s), collected fortnightly at a.m. and p.m. milking for 4 years. Univariate mixed models were used for estimating the evolution of traits with lactation stage and parity number and the relative weights of sire and individual variances within date and lactation and across lactations. As general trend, MMY and SMY decreased with lactation stage. SMY and its ratio with TMY increased from first to fourth parity. TL increased and MMF and AMF decreased with lactation stage and parity number. Machine milking time decreased with lactation stage and increased in adult ewes less than proportionally to the variation in machine milk yield. Most of milkability traits were highly repeatable within date. Within lactation repeatability was high for MMY, MMF and LT and moderate for TMY, SMY and AMF. Similar within date, within lactation and across lactations repeatability estimates for MMF and LT suggest that these traits are affected by random sources of variation, both environmental and genetic, which are constant in time. The proportion of the sire variance respect to the overall phenotypic variance ranged from 4% for MMT to 27% for MMF. These proportions were particularly high for MMY, LT, AMF and MMF and low for SMY and MMT. All the milk emission traits were favorably correlated between them and with milk yield. Only SMY showed low individual correlation with the other traits. Results suggest that milk emission traits are genetically determined and can be improved through selection. LT and MMF are the most relevant measurements to characterize the ewes’ machine milking speed due to the high repeatability and the favorable correlation with MMT. [Copyright &y& Elsevier]

It is necessary to identify traits that are simple to measure and correlated with milk yield to select ewes for dairying from existing populations of sheep in Australia. We studied 217 primiparous and 113 multiparous (second parity, n = 51; third parity, n = 40; and fourth parity, n = 22) East Friesian crossbred ewes, for 2 consecutive lactations, that were milked by machine following a period of suckling (24 to 28 d). We measured lamb growth, milk production, milk yield, and residual milk during early lactation (

Abstract: A mechanistic model of the mammary gland able to simulate the milk production process in dairy sheep was constructed by using a computer-aided simulation via object-oriented modelling. Such an approach, rather innovative in animal science, allows the construction of complex models avoiding the use of non-linear differential equations. The model was structured into three sub units: alveolar, energy and milk sub-models. It was used to mimic the milk production process of dairy sheep. Moreover, the model was used to simulate the effects on milk production of external stresses represented by the variation in milking frequency and a reduction in the energy supplied to the animal with the diet. [Copyright &y& Elsevier]

Abstract: 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 <0.05) the percentage of machine milk (82.9%). There were no significant differences among the groups for milk composition, milk flow rate and SCC, but there was a difference in log SCC (P <0.05) between 38 and 50 kPa. The teat end wall thickness was lower at the lower vacuum level (38 kPa) after milking, and increased (P <0.001) as the vacuum level was raised to 50 kPa. The findings of this study suggest that with a lower vacuum level of 38 kPa, the ewes are milked better than those with 44 or 50 kPa. Also, the irritation of teats is considerably reduced, while no differences were seen regarding the health of the udder. [Copyright &y& Elsevier]

Breeders are increasingly interested in improving the machine milkability of Sardinian dairy sheep by selection for udder morphology. Nine-point linear scales were developed to appraise teat placement, degree of suspension of the udder, udder depth, and degree of separation of the 2 halves. Repeatabilities within and across lactation were estimated on an experimental flock. Ewes were scored at least 3 times a year from 1999 to 2003. Within-lactation repeatabilities were greater than 0.70 for all linear traits, whereas across-lactation repeatabilities ranged from 0.59 to 0.66. The first linear combination of basic traits, obtained by principal component analysis, was highly correlated with teat placement, degree of suspension of the udder, and udder depth and showed an across-lactation repeatability of 0.76. These results indicate that an accurate evaluation of animals is possible by a single, early lifetime score. Genetic parameters of linear udder traits were estimated using a REML method applied to a sire model. Data were selected from 76,984 scores of Sardinian yearling ewes collected by 31 classifiers from 1999 to 2004. Two models were compared, one fitting the contemporary group effect as fixed and the other as random. Heritabilities of udder traits ranged from 0.19 to 0.31. The model with the random contemporary group effect produced slightly higher heritabilities and higher correlations between the sires' estimated breeding values and the daughters' average scores. As a whole, the genetic correlations between udder traits were favorable, indicating that selection for one trait will produce a positive evolution of the overall udder conformation. In particular, the degree of suspension of the udder was highly correlated with udder depth (0.82). Genetic correlations with milk yield were unfavorable but generally low, with the exception of udder depth (-0.48). Genetic trends were estimated using an animal model. Only udder depth showed a negative constant genetic trend. Overall results indicated that genetic improvement of the udder morphology of Sardinian ewes is feasible, with major emphasis on teat placement and degree of udder suspension, traits showing the highest heritabilities and low unfavorable genetic correlations with milk yield. [ABSTRACT FROM AUTHOR]

Abstract: Two sets of data with a sum of 6318 lactations for 1391 Spanish Churra ewes, belonging to 10 flocks were used to study phenotypic, genetic and system efficiency parameters of lifetime traits in annual and accelerated lambing systems. The study included four life span traits, three productive traits and two reproductive traits. Trait averages for both milk yield and revenues from sold milk and weaned lambs were calculated per-day of lifetime, productive life and useful life. The animal model included flock and ewe birth year as fixed effects. Both effects contributed significantly to variation in most traits in the annual system while birth year was non-significant for most variables of the accelerated system. Milk production level was included in the model to analyze life span traits. It contributed significantly to variation in all life span traits in both systems. Means for productive and life span traits were significantly higher in the accelerated system compared with the annual system. The average interval between successive lambings was significantly shorter in the accelerated system, while age at first lambing was significantly lower in the annual system. Except for age at first lambing, heritability estimates were clearly lower in the case of the accelerated system (0.02 to 0.20) than in the annual system (0.08 to 0.45). Genetic correlations among traits were also lower in the case of the accelerated system. Failure to lamb three times in two consecutive years and the varying reproductive management among flocks in the accelerated system may be responsible for the differences in genetic results between the two systems. Improving reproductive performance is necessary, especially for the young high yielding ewes in the accelerated system. Management to ensure high fertility, especially among young ewes, would be of more importance than removing non-lambing ewes. [Copyright &y& Elsevier]

Teleme cheeses were manufactured from ewe's, goat's and cow's milk and mixture of ewe's and goat's milk. Physicochemical and biochemical analyses of the cheeses at various stages of ripening and storage were performed. Cheeses made from goat's milk had lower moisture content than those made from other milks. No significant differences in the mean values of protein, salt and water activity (a w ) of the different cheeses at all ages studied were found. Cheeses from goat's and cow's milk had higher contents of fat and fat in dry matter (FDM) compared to that of cheeses from ewe's milk and mixed milk. Significant differences were observed in the yield and yield on 56% moisture: cheeses from ewe's milk gave the highest yield and cheese from cow's milk the lowest. Significant differences were found in the ashes content of the different cheeses at all ages. No differences in cholesterol and cholesterol/fat contents of the four types of cheeses were found. Main and trace elements showed variability among the four cheeses. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the biological and economic efficiency of a seasonal pasture-based spring calving system of milk production on a high-rainfall, heavy-clay soil [Kilmaley (KMY)] to that on a lower-rainfall free-draining soil [Moorepark (MPN)] in Ireland. The physical performance data were obtained from a 3-year study (1998–2000) carried out at both sites. Analysis of the system of milk production at the two sites was undertaken using the Moorepark Dairy System Model. Herbage dry-matter production was greater at the MPN site with a greater proportion being produced between 1 September and 1 May. On average, over the 3 years, the system of milk production at the MPN site had a higher stocking rate (2·34 vs. 1·89 cows ha−1), higher milk production per cow (6421 vs. 5781 kg per cow), longer grazing season (250 vs. 149 d) and a higher proportion of the diet of the herd from grazed grass (0·70 vs. 0·40) than at KMY. Economic analysis showed that, in a 468 100 kg European Union milk quota scenario, the profitability at the MPN site was €28 417 greater than at the KMY site. At similar milk production per cow it was €19 138 greater. Monte Carlo simulation showed that the MPN site was stochastically dominant over the KMY site. Sensitivity analyses showed that farm profit was most sensitive to changes in milk price. The results also indicated that milk production in the future may not be sustainable economically on high-rainfall, heavy-clay soils in Ireland. [ABSTRACT FROM AUTHOR]

Ninety six lactating ewes of the Sfakian dairy sheep breed, divided into two equal groups were used. Three kilograms (79.5%) sliced orange silage mixture with by-products were offered daily to the animals as experimental treatment, replacing part of the maize grain/soybean meal/oat hay ration given to the controls. Microbiological and chemical analyses of silage showed that ensiling high moisture materials such as whole oranges is feasible. Silage pH from 4.1 before, dropped to 3.7 after ensiling. Colony forming units of yeasts and fungi in silage were approximately 200-fold lower at the end of the ensiling process. Silage DM was 16% lower at the end of ensiling (25.0 versus 21.0%). Orange silage mixture composition was CP 13.4, crude fibre 13.4, fat 2.3, ash 7.93, Ca 0.99 and P 0.7% on DM basis and proved palatable to sheep particularly due to its pleasant odour. Milk yield and composition were measured for a 6-week period. Overall daily milk yield was 12% higher for controls (769.0±28.9 g versus 680.0±21.0 g, P<0.05) but the situation was reversed for the last third of the lactation period. However, 6% fat corrected milk yields (821.0±31.8 versus 832.0±28.5) did not differ significantly. Ewes fed orange silage had 16% higher fat content in milk (P<0.05). Treatment differences in ewes’ body weight were not significant during the experimental period. Results show that the inclusion of ensiled sliced oranges to diets of lactating sheep is a viable proposition. [Copyright &y& Elsevier]

As ovine milk production increases in the United States, somatic cell count (SCC) is increasingly used in routine ovine milk testing procedures as an indicator of flock health. Ovine milk was collected from 72 East Friesian-crossbred ewes that were machine milked twice daily. The milk was segregated and categorized into three different SCC groups: <100,000 (group I); 100,000 to 1,000,000 (group II); and >1,000,000 cells/ ml (group III). Milk was stored frozen at -19°C for 4 mo. Milk was then thawed at 7°C over a 3-d period before pasteurization and cheese making. Casein (CN) content and CN-to-true protein ratio decreased with increasing SCC group 3.99, 3.97, to 3.72% CN, and 81.43, 79.72, and 79.32% CN to true protein ratio, respectively. Milk fat varied from 5.49, 5.67, and 4.86% in groups I, II, and III, respectively. Hard ewe's milk cheese was made from each of the three different SCC groups using a Manchego cheese manufacturing protocol. As the level of SCC increased, the time required for visual flocculation increased, and it took longer to reach the desired firmness for cutting the coagulum. The fat and moisture contents were lower in the highest SCC cheeses. After 3 mo, total free fatty acids (FFA) contents were significantly higher in the highest SCC cheeses. Butyric and caprylic acids levels were significantly higher in group III cheeses at all stages of ripening. Cheese graders noted rancid or lipase flavor in the highest SCC level cheeses at each of the sampling points, and they also deducted points for more body and textural defects in these cheeses at 6 and 9 mo. [ABSTRACT FROM AUTHOR]

This study was undertaken to evaluate the changes in the pattern of prolactin hormone associated with milk yield and milk composition in ewes. Moreover, the relationships of thyroxin, glucose, cholesterol and total protein with growth performance of lambs were investigated under southern Egypt local environmental conditions. Both ewes and lambs were of four genotypes namely, Ossimi (O), Saidi (S), Fl Chios-Ossimi (CO) and Fl Chios×Saidi (CS). Average daily milk yield, total milk yield and lactation period length were significantly (P<0.05) higher in ewes with Chios genetics than the local breeds. Moreover, CS ewes were superior in this respect compared with CO ewes. However, none of the milk constituents (fat, total solids, solids non-fat and lactose) was affected by genotype. Genotype of ewes had a significant (P<0.01) effect on prolactin hormone concentration being higher in crossbred ewes (CS and CO) than local ones (O or S). Across genotype, milk production was found to be positively correlated with plasma prolactin hormone concentration (r=0.667, P<0.05). Body weight of lambs (O, S, CO and CS) at birth, at weaning (2 months) and at 4-months-old significantly (P<0.01) differed among the various genotypes studied. CO lambs recorded the heaviest (P<0.05) birth and weaning weights. Plasma thyroxin (T4), glucose, cholesterol and total protein at birth, weaning and 4 months of age were significantly (P<0.05) higher in the Chios crossbred lambs. Plasma T4 hormone concentration was found to be negatively associated with age changes across genotypes r=−0.841, P<0.01). [Copyright &y& Elsevier]