Eight multiparus lactating goats, matched for parity and days in milk were used to evaluate the e... more Eight multiparus lactating goats, matched for parity and days in milk were used to evaluate the effects of recombinant bovine somatotropin (rbST) administration on milk yield and composition, as well as on certain metabolic parameters. The experiment was a switch-back design, with three periods lasting 28 days each. Animals were divided into two groups (n=4) and treatments consisted of subcutaneous
Digestion and performance of lactating dairy ewes fed diets with soy hulls (SH), with or without ... more Digestion and performance of lactating dairy ewes fed diets with soy hulls (SH), with or without dietary fat supplements, as a replacement for maize in concentrate diets were evaluated in digestion and milk performance trials. In the digestion trial, three fistulated wether sheep were used in a 3×3 Latin square experimental design. The diets consisted of 400g hay+600g concentrate with
The conjugated linoleic acid (CLA) content of grazing sheep and goat milk fat, throughout their l... more The conjugated linoleic acid (CLA) content of grazing sheep and goat milk fat, throughout their lactation period, was examined. Six sheep and six goat representative farms were selected at random and milk samples were taken at monthly intervals for fatty acids profile determination. Sheep and goat nutrition was based on natural grazing and on supplementary feeding during the winter months. From April onwards, grazing native pastures was the only source of feed for sheep and goats. The University farm whose sheep are kept indoors all year round without any grazing, was also used as reference. Fifteen individual milk samples were also taken in April from a sheep and goat farm respectively, in order to see the variability of CLA inside the farm. The results showed that: a. the CLA content of grazing sheep and goat milk fat increased significantly in April–May (early growth stage of grass) and then declined while that of indoors kept sheep was more or less constant during the same period, b. the isomers cis-9, trans-11 and trans-10, cis-12 of CLA were found in grazing sheep milk fat, while in indoors kept sheep and goats' milk fat only the cis-9, trans-11 isomer was found, c. the CLA content of sheep milk fat was much higher than that of goats, d. a negative correlation between sheep milk fat and CLA content was found and e. there was considerable variation in milk fat CLA content between sheep and goat farms and inside the farms.
... oregano (oregano essential oil 3% w/w) and sage (sage essential oil 3% w/w). Subsequently, th... more ... oregano (oregano essential oil 3% w/w) and sage (sage essential oil 3% w/w). Subsequently, the samples from each treatment were stored at 4 °C, in the raw and cooked (at 85 °C for 30 min) state, and the antioxidant activity was determined after 1, 4, 8 and 12 days of storage. ...
The objective of this study was to describe and evaluate the feeding system of milking sheep in a... more The objective of this study was to describe and evaluate the feeding system of milking sheep in a typical mountainous area (Feneos of Korinthos, Greece), which comprises eight village communities. In this area, 23 000 sheep and 10000 goats are kept under an extensive livestock farming system and a semi-intensive feeding system. Available pasture, cultivated land and meadows comprise 16 800 ha, 4540 ha and 443 ha, respectively. Sheep graze throughout the year but herbage intake is sufficient to meet the animals' requirements only from April to June. During the summer, sheep graze cereal stubble and other crop residues left after harvesting. From October to March, animals are provided with concentrates and roughages. All of the roughages and part of the concentrates are farm grown. On an annual basis, concentrates, roughages and ingested herbage from grazing contribute 36%, 26% and 38% of total energy requirements, respectively, whereas supplementary feed only exceeds the animals' CP requirements. During winter the nutrient requirements of the sheep are not met, consequently animals lose weight (BC score I.552.51, but this is restored in the spring when there is usually plenty of grass. The rations fed during winter are not properly balanced, and there is usually an energy deficit and a protein surplus. No mineral supplements are fed, and some (about 18%) sheep suffer from subclinical Zn and Se deficiencies. It is concluded that the genetic potential of the sheep, under the feeding system of a typical mountain management region, has not been reached. Costs and benefits of supplementation need careful evaluation.
An experiment was conducted with the objective to study the interaction between breed and diet on... more An experiment was conducted with the objective to study the interaction between breed and diet on conjugated linoleic acid (CLA) and fatty acids profile (FA) content of milk fat of four pure of dairy sheep breeds (Awassi, Lacaune, Friesland and Chios). All sheep used in this study were kept in one flock under the same management. During the winter months
ABSTRACT The objective of this work was to study the effect of the supplementation of dairy ewes’... more ABSTRACT The objective of this work was to study the effect of the supplementation of dairy ewes’ diet with liquid methionine (ALIMET) on milk yield and milk composition, from late pregnancy to mid lactation period. Sixty 3-4 year old Boutsiko breed lactating dairy ewes with an average initial body weight 48±1.7 kg and good body condition (3.6), were divided into three groups (treatments), balanced according to milk yield. Ewes were fed 0.8 kg alfalfa hay and 0.8 kg of concen- trate daily. Ewes in Group A were fed a usual concentrate for lactating ewes (control), in Group B the control concentrate +1 g ALIMET /kg concentrate, and in Group C the control concentrate +3 g ALIMET /kg concentrate. Ewes were milked twice daily, and milk weights (yield) were recorded every 4 weeks, while milk samples were taken, on a percent basis (10%), for compositional analysis. The results showed that the inclusion of ALIMET significantly increased (p yield (by 6.8% in Group B and 12% in Group C), compared to control, FCM (6% fat) yield (by 5.5% in Group B and 13.6% in Group C), and milk fat, protein and non fat solids. The growth rate of lambs was 7% and 8% higher, for the suckling period of 42 days, for the Groups B and C, respectively, compared to control, but those differences were not sig- nificant. The average daily body weight change of ewes during the experimental lactation period was +0.6, +1.0 and - 0.2 kg for Groups A, B and C, respectively. Thus, supplementing the ewes’ diet with ALIMET, at a level of 3 g /kg con- centrate, had a positive effect on milk yield and milk composition.
The objective of this study was to evaluate the ability of lambs to regulate intake of mineral li... more The objective of this study was to evaluate the ability of lambs to regulate intake of mineral lick blocks (MLBs) with different trace mineral content when alfalfa hay and concentrates, also with a different trace mineral content, were available to lambs for ad libitum consumption. Twelve 4-month-old purebred Karagouniko lambs were divided into three groups, pen housed individually, and fed unchopped alfalfa hay and concentrates ad libitum. The three concentrates used consisted of a basal concentrate food supplemented (TM+) or not (TM−) with trace elements and a vitamin premix. This basal food of the third group (3TM) was supplemented with a premix in which the trace minerals added were three times the amount of the control group, TM+. The experiment lasted 66 days. The first 31 days were used as an adaptation period, and from the 32nd day two different MLBs were put in each pen. One of the MLBs was white in colour while the other was light pink and had a three-fold greater trace mineral content compared to the white one. Two weeks following the introduction of the MLBs (adaptation period), the behaviour of lambs was video recorded for 48 h per week for 3 weeks. Food and water intake and MLB consumption were recorded regularly and the Cu and Zn concentrations were determined in the blood plasma and the liver of the lambs. The average daily MLB intake, the number of visits to the MLBs, and the time spent by the lambs licking the MLBs were higher for the group TM− and lower for the 3TM group. However, the daily mineral intake from the ingested MLB represented only a very small proportion of the total mineral intake of the animals. The differences among the groups in plasma and liver Cu and Zn concentrations represented the quantities ingested via the diet rather the MLBs. In conclusion, the results of this experiment did not show clearly that the lambs could regulate the intake of MLB because they failed to exhibit a ‘mineral wisdom’ related to their physiological needs and mineral status.
The objective of this work was to compare two different lamb fattening systems. Twenty weaned mal... more The objective of this work was to compare two different lamb fattening systems. Twenty weaned male crossbred (Karagouniko 3 Boutsiko) lambs were divided into two equal groups (29 kg average body weight). Lambs of group A were kept exclusively on pasture for fattening, while lambs of group B were kept indoors in individual pens and fed 200 g of hay / lamb / day and concentrates ad libitum. Food intake and growth rate were recorded regularly and food conversion ratio was determined in both groups. Herbage growth (by HFRO sward stick), herbage yield (by cages) and herbage intake (by n-alkanes) were also determined. All lambs were slaughtered after 60 days and carcass characteristics were determined. The average DMI was 2.15 and 1.60 kg / lamb / day, and the average BW gain 200 and 246 g / day for groups A and B, respectively. Food conversion ratio was in favor of lambs of group B (10.75 vs. 6.52 kg DM / kg BW gain and 1.80 vs. 1.09 kg of dietary CP/ kg BW gain), but feeding costs (2.2 vs. 3.35 USD/ kg carcass) and labor costs were in favor of lambs of group A. The carcass weight of lambs kept on pasture was lower (P , 0.05) by 2.2 kg, but omental (P , 0.05) and perinephric (P , 0.001) fat were significantly heavier in animals of group B. It was concluded that the system of fattening lambs on pasture can allow for a higher margin to the farmer because of the lower inputs and the products of higher value, compared to the indoors fattening system. Moreover, this grazing system, operating under conditions of pronounced traditional character, can be physically, biologically and economically sustainable.
An experiment was conducted with 12 lactating dairy ewes and 12 goats with the objective to deter... more An experiment was conducted with 12 lactating dairy ewes and 12 goats with the objective to determine whether, under the same dietary treatments, the differences in their fatty acid (FA) profile with emphasis on cis-9 trans-11 CLA milk fat content, are reflected in the transcript levels of genes involved in FA and cis-9, trans-11 CLA biosynthesis. The animals were fed with two diets (A, B) in different days of milk (DIM) due to the different milk yield, body weight etc, in order to have the same food intake and to avoid dietary effects. Diet A was fed to the animals on a group basis as it is traditionally used in practice, while diet B was chosen to avoid individual feed intake variation which is usually observed in group feeding. The results showed that there are significantly lower mRNA levels of acetyl-CoA carboxylase (ACC) in sheep mammary gland compared with those of goats, independently from the diet fed. The same trend was observed with the mRNA level of FA synthase (FAS), but the results were significant only for diet A. The mRNA level of lipoprotein lipase (LPL) in the mammary gland did not differ between sheep and goats fed with diet A. In addition, the concentration of cis-9 trans-11 CLA content was significantly higher in sheep milk fat compared with those of goats. This is in accordance with the significant higher levels on mRNA of stearoyl-CoA desaturase (SCD) which were observed in their mammary adipocytes of sheep compared with those of goats, independently of the fed diet (A or B). In conclusion, these findings demonstrate that the differences between sheep and goats, concerning cis-9, trans-11 CLA and FA milk fat content, under the same dietary treatments could be explained in part by the differences in mRNA of SCD and lipogenic genes in their mammary gland.
A number of studies have shown that the rumenic acid (RA = cis-9 trans-11 C 18:2 CLA) content of ... more A number of studies have shown that the rumenic acid (RA = cis-9 trans-11 C 18:2 CLA) content of milk fat is usually higher in sheep than in goats, due partly to different dietary regimens. An experiment was conducted with 12 lactating dairy ewes and 12 goats with the objective to compare the two animal species (sheep/goats) fed diet with the same forage/concentrate (F/C) ratio, on their milk fatty acids (FA) profile with emphasis on RA and vaccenic acid (VA) production. The experiment was carried out in three consecutive phases, lasted 3 weeks each, immediately after weaning of lambs and kids. In phase I, the ewes and the goats were fed according to their maintenance and lactation requirements, with 14 kg alfalfa hay, 4 kg wheat straw and 12 kg concentrate the 12 ewes (F/C ratio = 60/40), and with 14 kg alfalfa hay, 4 kg straw and 24 kg concentrate the 12 goats (F/C ratio = 43/57). In phase II, 14 kg alfalfa hay, 4 kg straw and 14 kg concentrate were offered daily to each group of sheep and goats, with a F/C ratio = 56/44. In phase III, all ewes and goats were fed individually with 0.8 kg alfalfa hay, 0.2 kg wheat straw and 0.8 kg concentrate daily with a F/C ratio = 56/44. The results showed that the different F/C ratio between sheep and goats diets, in phase I, changed significantly the milk FA profile, with no significant difference in RA and VA milk fat content between sheep and goats in phase I. In phases II (group feeding) and III (individual feeding), where sheep and goats fed with the same amount of food of the same F/C ratio, the sheep milk fat had higher RA and VA content compared to goats. In conclusion, these findings support the hypothesis that there are species differences, as RA and VA production concerns, which needs further investigation.
The cis-9, trans-11 C18:2 (CLA) content in milk fat of four pure sheep breeds (Awassi, Lacaune, F... more The cis-9, trans-11 C18:2 (CLA) content in milk fat of four pure sheep breeds (Awassi, Lacaune, Friesland and Chios) was examined. All sheep were kept indoors all year round under the same feeding practices, without any grazing at all. Sheep nutrition was based on alfalfa hay and concentrates. A total of 237 individual milk samples were collected at three sampling times (December, January and March) from sheep of different parity and different days in milk, for CLA determination. The results showed that: (a) there was a large variation in milk fat CLA content among individuals consuming the same diet, (b) the CLA content of milk fat was lower in Friesland breed, compared to the other three breeds but without any significant difference among the four sheep breeds, (c) the CLA content of milk fat was not affected by ewes parity or days in milk, (d) there was a negative but not significant correlation between milk fat and CLA concentration, (e) the CLA content of milk fat was not correlated with milk yield. In conclusion, no others factors, such as breed, parity, days in milk, etc., can affect CLA content in milk fat, which means that the dietary ones remain the sovereign factors explaining the highest proportion of CLA content variability in sheep milk fat.
The effect of supplemental animal fat, or animal fat and rumen protected methionine, on lactating... more The effect of supplemental animal fat, or animal fat and rumen protected methionine, on lactating dairy ewes production was evaluated in the present study. Twelve dairy pregnant ewes of the Karagouniko breed, with two embryos, were allocated to three groups (treatments), in order to examine the effect of three diets: control (C), diet with animal fat at 7% of concentrates’ DM (F) and diet F plus 5 g rumen protected methionine (RPM) per kg of concentrate (F+m). The experiment started 2 weeks before lambing and continued for the 13 first weeks of lactation. During the experiment, dry matter intake (DMI), energy supply, daily milk yield and milk composition were determined. Prepartum, DMI and energy supply did not differ between treatments C and F+m. During the first 7 weeks of lactation (from lambing to weaning), the inclusion of fat in the diet increased DMI, energy supply (P<0.001), and the milk lactose content (P<0.05), but decreased the milk fat content (P<0.05). The inclusion of fat with RPM in the diet resulted in an increase (P<0.001) of DMI, milk yield and daily fat and protein yield, compared to treatments C and F. After weaning (8–13th week of lactation), significant differences were observed only in DMI and energy intake which increased (P<0.001) for treatments F and F+m. Milk fat content reduced (P<0.05) for treatments F and F+m, compared to control, but the mean daily milk fat and protein yield did not change significantly. For the first 13 weeks of lactation there was not treatment effect on milk protein profile, while the concentration of short chain fatty acids of milk fat was reduced (P<0.001) and that of short chain fatty acids increased (P<0.001) for treatments F and F+m, compared to treatment C. From the results of this experiment it is concluded that the inclusion of animal fat in sheep diets had no significant effect on ewes milk yield, while the use of rumen protected methionine, combined with animal fat, in diets of high producing ewes, at least at the first stage of lactation, increased significantly milk yield.
The objective of this study was to investigate whether there is a difference in chemical composit... more The objective of this study was to investigate whether there is a difference in chemical composition and particularly in fatty acid (FA) profile, with emphasis on cis-9, trans-11 CLA, of milk obtained from conventional and organic dairy sheep and goats farms under the farming conditions practiced in Greece. Four dairy sheep and four dairy goat farms, representing common conventional production systems and another four dairy sheep and four dairy goat farms, organically certified, representing organic production and feeding systems were selected from all over Greece. One hundred and sixty two individual milk samples were collected from those farms in January-February 2009, about three months after parturition. The milk samples were analyzed for their main chemical constituents and their FA profile. The results showed that the production system affected milk chemical composition: in particular fat content was lower in the organic sheep and goats milk compared with the corresponding conventional. Milk from organic sheep had higher content in MUFA, PUFA, a-LNA, cis-9, trans-11 CLA, and v-3 FA, whereas in milk from organic goats a-LNA and v-3 FA content was higher than that in conventional one. These differences are, mainly, attributed to different feeding practices used by the two production systems. The results of this study show that the organic milk produced under the farming conditions practiced in Greece has higher nutritional value, due to its FA profile, compared with the respective conventional milk.
Six castrated male Karagouniko sheep, offered three levels of water, were used in a 3Â3 Latin Squ... more Six castrated male Karagouniko sheep, offered three levels of water, were used in a 3Â3 Latin Square design to study the effects of mild water restriction on roughage intake and digestion. The three treatments were offered water ad libitum throughout the day (A), made available to the animals for 1 h daily (B) or 65% of the water consumed ad libitum (C). Sheep in Treatment A consumed more water (181.9 g/kg BW 0.75 ) than the two water restriction regimes, which did not differ signi®cantly (B: 128.8, C: 117.5 g/kg BW 0.75 ) between them. Roughage dry matter intake and digestibility of nutrients did not differ signi®cantly between treatments. Non-signi®cant differences (p>0.05) were also observed in the rate of passage of undigested residues between treatments (A: 48.7, B: 56.9 and C: 54.5 %/h). It was concluded that the water restrictions usually applied during the dry season did not have any signi®cant effect on the nutrition of a local breed of sheep in Greece. #
... George Zervas Corresponding Author Contact Information , E-mail The Corresponding Author , El... more ... George Zervas Corresponding Author Contact Information , E-mail The Corresponding Author , Eleni Tsiplakou. ... 1. Introduction. Sheep and goats have been raised for milk, meat and wood for thousands of years and were milked before cows. ...
Epidemiological and experimental data support the hypothesis of 'fetal programming', which propos... more Epidemiological and experimental data support the hypothesis of 'fetal programming', which proposes that alterations in fetal nutrition and endocrine status lead to permanent adaptations in fetal homeostatic mechanisms, producing long-term changes in physiology and determine susceptibility to later disease. Altered hypothalamic-pituitaryadrenal (HPA) axis function has been proposed to play an important role in programming of disease risk. The aim of the present study was to examine the effects of maternal nutrient restriction imposed during different periods of gestation on the HPA axis function in sheep, at different ages postnatal. Pregnant ewes were fed a 50% nutrient-restricted diet from days 0-30 (group R1, nZ7), or from days 31-100 of gestation (group R2, nZ7) or a control 100% diet throughout pregnancy, (Control, nZ8). Blood samples were collected at 10-day intervals from day 40 of gestation to term. Lambs were born naturally and fed to appetite throughout the study period. At 2, 5 . 5, and 10 months of age lambs were given an i.v. injection of corticotrophin-releasing hormone (CRH) and blood samples were collected at K15, 0, 15, 30, 60, 120, and 180 min postinjection. Maternal cortisol levels were significantly higher (P!0 . 05) in group R1 compared with the other two groups, whereas maternal insulin levels were lower (P!0 . 05) in group R2 compared with control. Birth weight of lambs was not affected by the maternal nutritional manipulation. The area under the curve for ACTH and cortisol response to CRH challenge was greater (P!0 . 05) in lambs of group R1 at two months of age, whereas no difference was detected at the ages of 5 . 5 and 10 months. However, significantly higher (P!0 . 01) basal cortisol levels were observed in lambs of R1 group at 5 . 5 months of age.
Effects of long term under-and over-feeding on goats' milk chemical composition and fatty acid (F... more Effects of long term under-and over-feeding on goats' milk chemical composition and fatty acid (FA) profile, on blood plasma insulin and on leptin concentrations were determined. Lactating goats were divided into three sub-groups and fed the same ration in quantities covering 70% (under-feeding), 100% (control) and 130% (over-feeding) of their energy and crude protein requirements. Chemical composition of milk, blood plasma FA profile and insulin plasma concentrations were affected by long term underand over-feeding. With regard to milk FA profile, under-feeding reduced the concentrations of C 16:0 and long chain FAs and increased that of C 18:0 and polyunsaturated FA in milk fat compared with controls. Over-feeding increased the cis9, trans11 C 18:2 milk fat content compared with the control and increased the medium chain FAs compared with under-feeding. Lean goats responded differently to under-and over-feeding in terms of leptin level changes, possibly due to their low fat stores.
The objective of this study was to compare the mean retention time (MRT): (a) between sheep and g... more The objective of this study was to compare the mean retention time (MRT): (a) between sheep and goats when they fed in groups with the same diet, the same amount of food and forage to concentrate (F/C) ratio and (b) between group and individual feeding in each animal specie (the same diet, the same amount of food and F/C ratio). Twelve, 3-4 years old, Friesian crossed dairy ewes and twelve, 3-5 years old, Alpine crossed dairy goats were used for the experiment. The animals were fed with a diet, consisted of alfalfa hay, wheat straw and concentrate, in two treatments. In Treatment A the animals fed on a group basis as it is traditionally used in practise, while in Treatment B the diet was offered individually toin each animal, in order to have fully comparable feeding level among animals and between treatments. Each Treatment (A and B) lasted 3 weeks. The results of this study have shown that: sheep had significantly longer rumen retention time (RRT) (30.03 vs. 14.43) and mean retention time (MRT) (40.80 vs. 27.81), and shorter transit time (TT) (8.86 vs. 11.49) than goats, while the caecum retention time (CRT) did not differ between the two species in Treatment A (group feeding). The comparison between group (Treatment A) and individual feeding (Treatment B) in goats or in sheep has shown that there were no significant differences as RRT, CRT, TT and MRT concerns. In conclusion, animal species (sheep vs. goat) was the main factor which affected the MRT, RRT and TT when the animals were fed in groups with the same diet, amount of food and F/C ratio, while the feeding technique (group vs. individual) had no effect on those parameters in both animal species.
Eight multiparus lactating goats, matched for parity and days in milk were used to evaluate the e... more Eight multiparus lactating goats, matched for parity and days in milk were used to evaluate the effects of recombinant bovine somatotropin (rbST) administration on milk yield and composition, as well as on certain metabolic parameters. The experiment was a switch-back design, with three periods lasting 28 days each. Animals were divided into two groups (n=4) and treatments consisted of subcutaneous
Digestion and performance of lactating dairy ewes fed diets with soy hulls (SH), with or without ... more Digestion and performance of lactating dairy ewes fed diets with soy hulls (SH), with or without dietary fat supplements, as a replacement for maize in concentrate diets were evaluated in digestion and milk performance trials. In the digestion trial, three fistulated wether sheep were used in a 3×3 Latin square experimental design. The diets consisted of 400g hay+600g concentrate with
The conjugated linoleic acid (CLA) content of grazing sheep and goat milk fat, throughout their l... more The conjugated linoleic acid (CLA) content of grazing sheep and goat milk fat, throughout their lactation period, was examined. Six sheep and six goat representative farms were selected at random and milk samples were taken at monthly intervals for fatty acids profile determination. Sheep and goat nutrition was based on natural grazing and on supplementary feeding during the winter months. From April onwards, grazing native pastures was the only source of feed for sheep and goats. The University farm whose sheep are kept indoors all year round without any grazing, was also used as reference. Fifteen individual milk samples were also taken in April from a sheep and goat farm respectively, in order to see the variability of CLA inside the farm. The results showed that: a. the CLA content of grazing sheep and goat milk fat increased significantly in April–May (early growth stage of grass) and then declined while that of indoors kept sheep was more or less constant during the same period, b. the isomers cis-9, trans-11 and trans-10, cis-12 of CLA were found in grazing sheep milk fat, while in indoors kept sheep and goats' milk fat only the cis-9, trans-11 isomer was found, c. the CLA content of sheep milk fat was much higher than that of goats, d. a negative correlation between sheep milk fat and CLA content was found and e. there was considerable variation in milk fat CLA content between sheep and goat farms and inside the farms.
... oregano (oregano essential oil 3% w/w) and sage (sage essential oil 3% w/w). Subsequently, th... more ... oregano (oregano essential oil 3% w/w) and sage (sage essential oil 3% w/w). Subsequently, the samples from each treatment were stored at 4 °C, in the raw and cooked (at 85 °C for 30 min) state, and the antioxidant activity was determined after 1, 4, 8 and 12 days of storage. ...
The objective of this study was to describe and evaluate the feeding system of milking sheep in a... more The objective of this study was to describe and evaluate the feeding system of milking sheep in a typical mountainous area (Feneos of Korinthos, Greece), which comprises eight village communities. In this area, 23 000 sheep and 10000 goats are kept under an extensive livestock farming system and a semi-intensive feeding system. Available pasture, cultivated land and meadows comprise 16 800 ha, 4540 ha and 443 ha, respectively. Sheep graze throughout the year but herbage intake is sufficient to meet the animals' requirements only from April to June. During the summer, sheep graze cereal stubble and other crop residues left after harvesting. From October to March, animals are provided with concentrates and roughages. All of the roughages and part of the concentrates are farm grown. On an annual basis, concentrates, roughages and ingested herbage from grazing contribute 36%, 26% and 38% of total energy requirements, respectively, whereas supplementary feed only exceeds the animals' CP requirements. During winter the nutrient requirements of the sheep are not met, consequently animals lose weight (BC score I.552.51, but this is restored in the spring when there is usually plenty of grass. The rations fed during winter are not properly balanced, and there is usually an energy deficit and a protein surplus. No mineral supplements are fed, and some (about 18%) sheep suffer from subclinical Zn and Se deficiencies. It is concluded that the genetic potential of the sheep, under the feeding system of a typical mountain management region, has not been reached. Costs and benefits of supplementation need careful evaluation.
An experiment was conducted with the objective to study the interaction between breed and diet on... more An experiment was conducted with the objective to study the interaction between breed and diet on conjugated linoleic acid (CLA) and fatty acids profile (FA) content of milk fat of four pure of dairy sheep breeds (Awassi, Lacaune, Friesland and Chios). All sheep used in this study were kept in one flock under the same management. During the winter months
ABSTRACT The objective of this work was to study the effect of the supplementation of dairy ewes’... more ABSTRACT The objective of this work was to study the effect of the supplementation of dairy ewes’ diet with liquid methionine (ALIMET) on milk yield and milk composition, from late pregnancy to mid lactation period. Sixty 3-4 year old Boutsiko breed lactating dairy ewes with an average initial body weight 48±1.7 kg and good body condition (3.6), were divided into three groups (treatments), balanced according to milk yield. Ewes were fed 0.8 kg alfalfa hay and 0.8 kg of concen- trate daily. Ewes in Group A were fed a usual concentrate for lactating ewes (control), in Group B the control concentrate +1 g ALIMET /kg concentrate, and in Group C the control concentrate +3 g ALIMET /kg concentrate. Ewes were milked twice daily, and milk weights (yield) were recorded every 4 weeks, while milk samples were taken, on a percent basis (10%), for compositional analysis. The results showed that the inclusion of ALIMET significantly increased (p yield (by 6.8% in Group B and 12% in Group C), compared to control, FCM (6% fat) yield (by 5.5% in Group B and 13.6% in Group C), and milk fat, protein and non fat solids. The growth rate of lambs was 7% and 8% higher, for the suckling period of 42 days, for the Groups B and C, respectively, compared to control, but those differences were not sig- nificant. The average daily body weight change of ewes during the experimental lactation period was +0.6, +1.0 and - 0.2 kg for Groups A, B and C, respectively. Thus, supplementing the ewes’ diet with ALIMET, at a level of 3 g /kg con- centrate, had a positive effect on milk yield and milk composition.
The objective of this study was to evaluate the ability of lambs to regulate intake of mineral li... more The objective of this study was to evaluate the ability of lambs to regulate intake of mineral lick blocks (MLBs) with different trace mineral content when alfalfa hay and concentrates, also with a different trace mineral content, were available to lambs for ad libitum consumption. Twelve 4-month-old purebred Karagouniko lambs were divided into three groups, pen housed individually, and fed unchopped alfalfa hay and concentrates ad libitum. The three concentrates used consisted of a basal concentrate food supplemented (TM+) or not (TM−) with trace elements and a vitamin premix. This basal food of the third group (3TM) was supplemented with a premix in which the trace minerals added were three times the amount of the control group, TM+. The experiment lasted 66 days. The first 31 days were used as an adaptation period, and from the 32nd day two different MLBs were put in each pen. One of the MLBs was white in colour while the other was light pink and had a three-fold greater trace mineral content compared to the white one. Two weeks following the introduction of the MLBs (adaptation period), the behaviour of lambs was video recorded for 48 h per week for 3 weeks. Food and water intake and MLB consumption were recorded regularly and the Cu and Zn concentrations were determined in the blood plasma and the liver of the lambs. The average daily MLB intake, the number of visits to the MLBs, and the time spent by the lambs licking the MLBs were higher for the group TM− and lower for the 3TM group. However, the daily mineral intake from the ingested MLB represented only a very small proportion of the total mineral intake of the animals. The differences among the groups in plasma and liver Cu and Zn concentrations represented the quantities ingested via the diet rather the MLBs. In conclusion, the results of this experiment did not show clearly that the lambs could regulate the intake of MLB because they failed to exhibit a ‘mineral wisdom’ related to their physiological needs and mineral status.
The objective of this work was to compare two different lamb fattening systems. Twenty weaned mal... more The objective of this work was to compare two different lamb fattening systems. Twenty weaned male crossbred (Karagouniko 3 Boutsiko) lambs were divided into two equal groups (29 kg average body weight). Lambs of group A were kept exclusively on pasture for fattening, while lambs of group B were kept indoors in individual pens and fed 200 g of hay / lamb / day and concentrates ad libitum. Food intake and growth rate were recorded regularly and food conversion ratio was determined in both groups. Herbage growth (by HFRO sward stick), herbage yield (by cages) and herbage intake (by n-alkanes) were also determined. All lambs were slaughtered after 60 days and carcass characteristics were determined. The average DMI was 2.15 and 1.60 kg / lamb / day, and the average BW gain 200 and 246 g / day for groups A and B, respectively. Food conversion ratio was in favor of lambs of group B (10.75 vs. 6.52 kg DM / kg BW gain and 1.80 vs. 1.09 kg of dietary CP/ kg BW gain), but feeding costs (2.2 vs. 3.35 USD/ kg carcass) and labor costs were in favor of lambs of group A. The carcass weight of lambs kept on pasture was lower (P , 0.05) by 2.2 kg, but omental (P , 0.05) and perinephric (P , 0.001) fat were significantly heavier in animals of group B. It was concluded that the system of fattening lambs on pasture can allow for a higher margin to the farmer because of the lower inputs and the products of higher value, compared to the indoors fattening system. Moreover, this grazing system, operating under conditions of pronounced traditional character, can be physically, biologically and economically sustainable.
An experiment was conducted with 12 lactating dairy ewes and 12 goats with the objective to deter... more An experiment was conducted with 12 lactating dairy ewes and 12 goats with the objective to determine whether, under the same dietary treatments, the differences in their fatty acid (FA) profile with emphasis on cis-9 trans-11 CLA milk fat content, are reflected in the transcript levels of genes involved in FA and cis-9, trans-11 CLA biosynthesis. The animals were fed with two diets (A, B) in different days of milk (DIM) due to the different milk yield, body weight etc, in order to have the same food intake and to avoid dietary effects. Diet A was fed to the animals on a group basis as it is traditionally used in practice, while diet B was chosen to avoid individual feed intake variation which is usually observed in group feeding. The results showed that there are significantly lower mRNA levels of acetyl-CoA carboxylase (ACC) in sheep mammary gland compared with those of goats, independently from the diet fed. The same trend was observed with the mRNA level of FA synthase (FAS), but the results were significant only for diet A. The mRNA level of lipoprotein lipase (LPL) in the mammary gland did not differ between sheep and goats fed with diet A. In addition, the concentration of cis-9 trans-11 CLA content was significantly higher in sheep milk fat compared with those of goats. This is in accordance with the significant higher levels on mRNA of stearoyl-CoA desaturase (SCD) which were observed in their mammary adipocytes of sheep compared with those of goats, independently of the fed diet (A or B). In conclusion, these findings demonstrate that the differences between sheep and goats, concerning cis-9, trans-11 CLA and FA milk fat content, under the same dietary treatments could be explained in part by the differences in mRNA of SCD and lipogenic genes in their mammary gland.
A number of studies have shown that the rumenic acid (RA = cis-9 trans-11 C 18:2 CLA) content of ... more A number of studies have shown that the rumenic acid (RA = cis-9 trans-11 C 18:2 CLA) content of milk fat is usually higher in sheep than in goats, due partly to different dietary regimens. An experiment was conducted with 12 lactating dairy ewes and 12 goats with the objective to compare the two animal species (sheep/goats) fed diet with the same forage/concentrate (F/C) ratio, on their milk fatty acids (FA) profile with emphasis on RA and vaccenic acid (VA) production. The experiment was carried out in three consecutive phases, lasted 3 weeks each, immediately after weaning of lambs and kids. In phase I, the ewes and the goats were fed according to their maintenance and lactation requirements, with 14 kg alfalfa hay, 4 kg wheat straw and 12 kg concentrate the 12 ewes (F/C ratio = 60/40), and with 14 kg alfalfa hay, 4 kg straw and 24 kg concentrate the 12 goats (F/C ratio = 43/57). In phase II, 14 kg alfalfa hay, 4 kg straw and 14 kg concentrate were offered daily to each group of sheep and goats, with a F/C ratio = 56/44. In phase III, all ewes and goats were fed individually with 0.8 kg alfalfa hay, 0.2 kg wheat straw and 0.8 kg concentrate daily with a F/C ratio = 56/44. The results showed that the different F/C ratio between sheep and goats diets, in phase I, changed significantly the milk FA profile, with no significant difference in RA and VA milk fat content between sheep and goats in phase I. In phases II (group feeding) and III (individual feeding), where sheep and goats fed with the same amount of food of the same F/C ratio, the sheep milk fat had higher RA and VA content compared to goats. In conclusion, these findings support the hypothesis that there are species differences, as RA and VA production concerns, which needs further investigation.
The cis-9, trans-11 C18:2 (CLA) content in milk fat of four pure sheep breeds (Awassi, Lacaune, F... more The cis-9, trans-11 C18:2 (CLA) content in milk fat of four pure sheep breeds (Awassi, Lacaune, Friesland and Chios) was examined. All sheep were kept indoors all year round under the same feeding practices, without any grazing at all. Sheep nutrition was based on alfalfa hay and concentrates. A total of 237 individual milk samples were collected at three sampling times (December, January and March) from sheep of different parity and different days in milk, for CLA determination. The results showed that: (a) there was a large variation in milk fat CLA content among individuals consuming the same diet, (b) the CLA content of milk fat was lower in Friesland breed, compared to the other three breeds but without any significant difference among the four sheep breeds, (c) the CLA content of milk fat was not affected by ewes parity or days in milk, (d) there was a negative but not significant correlation between milk fat and CLA concentration, (e) the CLA content of milk fat was not correlated with milk yield. In conclusion, no others factors, such as breed, parity, days in milk, etc., can affect CLA content in milk fat, which means that the dietary ones remain the sovereign factors explaining the highest proportion of CLA content variability in sheep milk fat.
The effect of supplemental animal fat, or animal fat and rumen protected methionine, on lactating... more The effect of supplemental animal fat, or animal fat and rumen protected methionine, on lactating dairy ewes production was evaluated in the present study. Twelve dairy pregnant ewes of the Karagouniko breed, with two embryos, were allocated to three groups (treatments), in order to examine the effect of three diets: control (C), diet with animal fat at 7% of concentrates’ DM (F) and diet F plus 5 g rumen protected methionine (RPM) per kg of concentrate (F+m). The experiment started 2 weeks before lambing and continued for the 13 first weeks of lactation. During the experiment, dry matter intake (DMI), energy supply, daily milk yield and milk composition were determined. Prepartum, DMI and energy supply did not differ between treatments C and F+m. During the first 7 weeks of lactation (from lambing to weaning), the inclusion of fat in the diet increased DMI, energy supply (P<0.001), and the milk lactose content (P<0.05), but decreased the milk fat content (P<0.05). The inclusion of fat with RPM in the diet resulted in an increase (P<0.001) of DMI, milk yield and daily fat and protein yield, compared to treatments C and F. After weaning (8–13th week of lactation), significant differences were observed only in DMI and energy intake which increased (P<0.001) for treatments F and F+m. Milk fat content reduced (P<0.05) for treatments F and F+m, compared to control, but the mean daily milk fat and protein yield did not change significantly. For the first 13 weeks of lactation there was not treatment effect on milk protein profile, while the concentration of short chain fatty acids of milk fat was reduced (P<0.001) and that of short chain fatty acids increased (P<0.001) for treatments F and F+m, compared to treatment C. From the results of this experiment it is concluded that the inclusion of animal fat in sheep diets had no significant effect on ewes milk yield, while the use of rumen protected methionine, combined with animal fat, in diets of high producing ewes, at least at the first stage of lactation, increased significantly milk yield.
The objective of this study was to investigate whether there is a difference in chemical composit... more The objective of this study was to investigate whether there is a difference in chemical composition and particularly in fatty acid (FA) profile, with emphasis on cis-9, trans-11 CLA, of milk obtained from conventional and organic dairy sheep and goats farms under the farming conditions practiced in Greece. Four dairy sheep and four dairy goat farms, representing common conventional production systems and another four dairy sheep and four dairy goat farms, organically certified, representing organic production and feeding systems were selected from all over Greece. One hundred and sixty two individual milk samples were collected from those farms in January-February 2009, about three months after parturition. The milk samples were analyzed for their main chemical constituents and their FA profile. The results showed that the production system affected milk chemical composition: in particular fat content was lower in the organic sheep and goats milk compared with the corresponding conventional. Milk from organic sheep had higher content in MUFA, PUFA, a-LNA, cis-9, trans-11 CLA, and v-3 FA, whereas in milk from organic goats a-LNA and v-3 FA content was higher than that in conventional one. These differences are, mainly, attributed to different feeding practices used by the two production systems. The results of this study show that the organic milk produced under the farming conditions practiced in Greece has higher nutritional value, due to its FA profile, compared with the respective conventional milk.
Six castrated male Karagouniko sheep, offered three levels of water, were used in a 3Â3 Latin Squ... more Six castrated male Karagouniko sheep, offered three levels of water, were used in a 3Â3 Latin Square design to study the effects of mild water restriction on roughage intake and digestion. The three treatments were offered water ad libitum throughout the day (A), made available to the animals for 1 h daily (B) or 65% of the water consumed ad libitum (C). Sheep in Treatment A consumed more water (181.9 g/kg BW 0.75 ) than the two water restriction regimes, which did not differ signi®cantly (B: 128.8, C: 117.5 g/kg BW 0.75 ) between them. Roughage dry matter intake and digestibility of nutrients did not differ signi®cantly between treatments. Non-signi®cant differences (p>0.05) were also observed in the rate of passage of undigested residues between treatments (A: 48.7, B: 56.9 and C: 54.5 %/h). It was concluded that the water restrictions usually applied during the dry season did not have any signi®cant effect on the nutrition of a local breed of sheep in Greece. #
... George Zervas Corresponding Author Contact Information , E-mail The Corresponding Author , El... more ... George Zervas Corresponding Author Contact Information , E-mail The Corresponding Author , Eleni Tsiplakou. ... 1. Introduction. Sheep and goats have been raised for milk, meat and wood for thousands of years and were milked before cows. ...
Epidemiological and experimental data support the hypothesis of 'fetal programming', which propos... more Epidemiological and experimental data support the hypothesis of 'fetal programming', which proposes that alterations in fetal nutrition and endocrine status lead to permanent adaptations in fetal homeostatic mechanisms, producing long-term changes in physiology and determine susceptibility to later disease. Altered hypothalamic-pituitaryadrenal (HPA) axis function has been proposed to play an important role in programming of disease risk. The aim of the present study was to examine the effects of maternal nutrient restriction imposed during different periods of gestation on the HPA axis function in sheep, at different ages postnatal. Pregnant ewes were fed a 50% nutrient-restricted diet from days 0-30 (group R1, nZ7), or from days 31-100 of gestation (group R2, nZ7) or a control 100% diet throughout pregnancy, (Control, nZ8). Blood samples were collected at 10-day intervals from day 40 of gestation to term. Lambs were born naturally and fed to appetite throughout the study period. At 2, 5 . 5, and 10 months of age lambs were given an i.v. injection of corticotrophin-releasing hormone (CRH) and blood samples were collected at K15, 0, 15, 30, 60, 120, and 180 min postinjection. Maternal cortisol levels were significantly higher (P!0 . 05) in group R1 compared with the other two groups, whereas maternal insulin levels were lower (P!0 . 05) in group R2 compared with control. Birth weight of lambs was not affected by the maternal nutritional manipulation. The area under the curve for ACTH and cortisol response to CRH challenge was greater (P!0 . 05) in lambs of group R1 at two months of age, whereas no difference was detected at the ages of 5 . 5 and 10 months. However, significantly higher (P!0 . 01) basal cortisol levels were observed in lambs of R1 group at 5 . 5 months of age.
Effects of long term under-and over-feeding on goats' milk chemical composition and fatty acid (F... more Effects of long term under-and over-feeding on goats' milk chemical composition and fatty acid (FA) profile, on blood plasma insulin and on leptin concentrations were determined. Lactating goats were divided into three sub-groups and fed the same ration in quantities covering 70% (under-feeding), 100% (control) and 130% (over-feeding) of their energy and crude protein requirements. Chemical composition of milk, blood plasma FA profile and insulin plasma concentrations were affected by long term underand over-feeding. With regard to milk FA profile, under-feeding reduced the concentrations of C 16:0 and long chain FAs and increased that of C 18:0 and polyunsaturated FA in milk fat compared with controls. Over-feeding increased the cis9, trans11 C 18:2 milk fat content compared with the control and increased the medium chain FAs compared with under-feeding. Lean goats responded differently to under-and over-feeding in terms of leptin level changes, possibly due to their low fat stores.
The objective of this study was to compare the mean retention time (MRT): (a) between sheep and g... more The objective of this study was to compare the mean retention time (MRT): (a) between sheep and goats when they fed in groups with the same diet, the same amount of food and forage to concentrate (F/C) ratio and (b) between group and individual feeding in each animal specie (the same diet, the same amount of food and F/C ratio). Twelve, 3-4 years old, Friesian crossed dairy ewes and twelve, 3-5 years old, Alpine crossed dairy goats were used for the experiment. The animals were fed with a diet, consisted of alfalfa hay, wheat straw and concentrate, in two treatments. In Treatment A the animals fed on a group basis as it is traditionally used in practise, while in Treatment B the diet was offered individually toin each animal, in order to have fully comparable feeding level among animals and between treatments. Each Treatment (A and B) lasted 3 weeks. The results of this study have shown that: sheep had significantly longer rumen retention time (RRT) (30.03 vs. 14.43) and mean retention time (MRT) (40.80 vs. 27.81), and shorter transit time (TT) (8.86 vs. 11.49) than goats, while the caecum retention time (CRT) did not differ between the two species in Treatment A (group feeding). The comparison between group (Treatment A) and individual feeding (Treatment B) in goats or in sheep has shown that there were no significant differences as RRT, CRT, TT and MRT concerns. In conclusion, animal species (sheep vs. goat) was the main factor which affected the MRT, RRT and TT when the animals were fed in groups with the same diet, amount of food and F/C ratio, while the feeding technique (group vs. individual) had no effect on those parameters in both animal species.
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