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1.
Medium wool ewes were injected with vitamin E and(or) Se over a 2-yr period to evaluate the influence of these treatments on reproduction. Ewes were divided randomly into four groups, consisting of a control, plus groups receiving monthly sc injections of either 272 iu vitamin E, 4 mg Se or 272 IU vitamin E plus 4 mg Se during pregnancy. Selenium administration increased (P less than .05) ewe blood Se concentrations, but had no effect (P greater than .10) on fertility (number of ewes lambing of ewes bred), prolificacy (number of lambs born/ewe lambing) or lamb sex ratio. Preweaning survival of lambs was increased (P less than .05) by ewe treatments with either Se or vitamin E and thus, treated ewes weaned approximately 20% more lambs/ewe mated than did control ewes.  相似文献   

2.
The aim of this work was to investigate whether Cu, alone or in combination with Mo, reduces the Se status of sheep. Thirty-six Hampshire ewes were separated prior to mating into four treatment groups of nine sheep each. The four groups consisted of 1) basal (alfalfa hay or legume-grass low-moisture silage, corn, oats), 2) basal plus 10 mg Cu/kg diet, 3) basal plus 10 mg Mo/kg and 4) basal plus Cu and Mo (each 10 mg/kg). Copper and Mo were added to both ewe and lamb diets. Treatments continued until lambs were weaned at 10 wk postpartum. The basal ewe diet contained, in mg/kg, 5.6 Cu, .05 Se and 1.0 Mo. The basal lamb diet contained, in mg/kg, 6.1 Cu, .07 Se and less than 1.0 Mo. Sulfur concentrations in the ewe and lamb diets were .24% and .20%, respectively. Copper supplements increased, and Mo supplements decreased, the concentration of Cu in the livers of ewes and lambs (P less than .05). Despite this, there were no effects of treatment on Se concentration or glutathione peroxidase activity in blood or tissues. Selenium levels in plasma of all ewes declined throughout pregnancy and lactation, indicating that .05 mg/kg Se was insufficient for the maintenance of Se status during pregnancy in Hampshire ewes. Copper and Se levels (mg/kg fresh weight) in the liver of lambs at weaning for Treatments 1 through 4 were 48 and .13, 158 and .10, 11 and .11, and 136 and .13, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
A 2 x 2 factorial arrangement of treatments with 78 mature ewes was used to evaluate the effects of supplementing the pregnant ewe's diet with high levels of minerals and vitamin E on immunoglobulin G (IgG) absorption by the lamb and whether any altered efficacy of IgG absorption was due to the colostrum or to the lamb. The ewes were estrus-synchronized in October and housed in wk 10 of gestation. In the final 7 wk of gestation, a grass silage-based diet, offered ad libitum, was supplemented with 500 g of a 19% CP concentrate, and from 1 wk later until lambing, half the ewes was offered 48 g of a mineral/vitamin supplement containing 6.5 g of Ca, 4.9 g of P, 5.9 g of Mg, 4.0 g of Na, 790 mg of Zn, 3.5 mg of Se, 40 mg of I, 200 mg of Mn, 20 mg of Co, and 40 IU of vitamin E. At birth, the lambs were allocated to one of four treatments in a 2 x 2 factorial arrangement, with lamb origin and colostrum origin as the two factors. The lambs born to ewes not offered the mineral supplement were fed colostrum obtained from their own dams or from ewes in the mineral-supplemented treatment, whereas lambs born to ewes given supplemental minerals were fed colostrum obtained either from their dams or from ewes in the control treatment. The ewes were milked at 1, 10, and 18 h postpartum and the lambs were fed using a stomach tube. A 5-mL blood sample was taken from each lamb at 24 h postpartum for IgG analysis. The level of fecal adhesion to the upper tail/rump area of the lamb was subjectively scored at 72 h postpartum. There was no difference in gestation length, lamb birth weight, colostrum yield, or IgG production (P = 0.16 to 0.82). When ewes were fed supplemental minerals, the serum IgG content of the progeny was lower than in their control counterparts (6.8 vs. 16.1 g/L; P < 0.001), regardless of whether the lamb received colostrum from ewes with or without access to supplementary minerals. The difference in serum IgG concentrations at 24 h postpartum was a direct reflection of a compromised efficiency in IgG absorption. The progeny of ewes with access to minerals had higher (P < 0.05) levels of fecal adhesion, which was not related to the origin of the colostrum, indicating altered digestive function in these lambs. We conclude, using the sheep as a model, that high mineral intakes in late pregnancy not only lower serum IgG concentrations in the lamb, but also that high mineral intakes result in the neonate being preprogrammed at birth so that it is born with a compromised ability to absorb colostral IgG.  相似文献   

4.
Data on ewe body weights and on lamb birth and weaning weights and survival rates were recorded on a total of 557 multiparous Rambouillet, Hampshire X Suffolk and Synthetic I (composite of Finnish Landrace, Rambouillet and Polled Dorset) ewes in two experiments started after the first trimester of gestation. In Exp. 1, a 2 X 2 factorial arrangement of treatments included all combinations of low (.24% in gestation and .48% in lactation), or high (.80%) dietary Ca and low (20 ppm) or high (74 ppm) dietary Zn. No effect of dietary Ca or Zn level and no Ca X Zn interaction with respect to number of lambs born or weaned, birth weight, weaning weight or survival rate of the lambs or body weight of the ewes was shown. Mean number of lambs born was 1.63 +/- .71 with a survival rate of 85.0 +/- .3% and a weaning weight (59 d) of 19.4 +/- 4.4 kg. Experiment 2 was a repeat of Exp. 1 except that two intramuscular injections of vitamins A, D and E (d 65 and 93 of experiment) were given to one-half of the ewes in each diet group. There was no effect of dietary Ca or Zn level or of vitamin administration on ewe body weight changes, number of lambs born (1.89 +/- .55), survival rate (86.6 +/- .3%), lamb birth weight 4.6 +/- 1.5 kg) or lamb weaning weight (23.2 +/- 7.2 kg). Blood plasma Ca, inorganic P and Mg concentrations of ewes in late pregnancy were unaffected by diet or vitamin injections.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Twin-bearing Targhee ewes (Exp. 1, 1 yr, n = 42) and 1,182 single- and twin-bearing whiteface range ewes (Exp. 2, n = 8 experimental units over 2 yr) were used in a 2 x 2 factorial arrangement of treatments to determine the effect of supplemental energy source and level of vitamin E supplement on lamb serum metabolites and thermogenesis (Exp. 1) and on lamb growth (Exp. 2). During late gestation, ewes were individually fed (Exp. 1) or group-fed (Exp. 2) a daily supplement. Supplements were 226 g/ewe of daily safflower seed (DM basis; SS) with either 350 IU/ewe daily (VE) or no added supplemental (VC) vitamin E; or 340 g/ewe daily of a barley-based grain supplement (DM basis; GC) and either VE or VC. One hour postpartum in Exp. 1, twin-born lambs were placed in a 0 degrees C dry cold chamber for 30 min. Lamb rectal temperature was recorded every 60 s and blood samples were taken immediately before and after cold exposure. In Exp. 2, lambs were weighed at birth, at turnout from confinement to spring range (32 d of age +/- 7; turnout), and at weaning (120 d of age +/- 7). Ewes were weighed at turnout and weaning. In Exp. 1, a level of vitamin E x energy source interaction was detected (P < 0.10) for body temperature and change in NEFA and glucose concentrations. Lambs from SSVC ewes had the lowest (P = 0.01) body temperature and had decreased (P = 0.08) NEFA concentration. The SS lambs tended to have decreased (P < 0.11) concentrations of blood urea N (BUN) and thyroxine at 0 min than did lambs born to GC ewes. After 30 min of cold exposure, SS lambs had increased and GC lambs had decreased BUN, triiodothyronine, and triiodothyronine:thyroxine concentrations (P < 0.10). In Exp. 2, kilograms of lamb per ewe at turnout and weaning and lamb survival at weaning were greater (P < 0.07) for GC than SS lambs. Based on the decreased body temperature in SSVC lambs at birth, the greater change in BUN during the cold exposure for SS than GC lambs, and the decreased survival rate for SS than GC lambs, SSVC-supplemented ewes appeared to give birth to lambs with an apparently decreased energetic capacity. This may compromise the ability of the newborn lamb to adapt to extreme environmental conditions.  相似文献   

6.
Forty-eight Blackbelly X Dorset, 27 Finnish, 26 Finnish X Dorset, 28 Rambouillet and 8 Dorset Suffolk-sired lambs were used in this experiment. Three weeks before lambing, one-half of the ewes received a selenium emulsion (Se-E) containing .05 mg selenium and 3.7 IU of vitamin E/kg body weight (BW). A 2 X 3 X 2 factorial arrangement was used; lambs from either treated or nontreated ewes were randomly assigned irrespective of breed to one of six treatment combinations consisting of 0 or .025 mg/kg BW selenium (Se) injected at birth or two .025 mg/kg BW Se injections, one at birth and one 2 to 3 wk later, and two levels of injectable Vitamin E (E; 0 and 100 IU) given at birth. Both lambs and ewes were provided access to 75% concentrate diets supplemented with Se and E at recommended NRC levels. Plasma activity of creatine phosphokinase (CPK) was highest at 1 d of age and exhibited decreases (P less than .001) over time. In lambs, the E injection tended to decrease plasma activity of CPK. Plasma glutathione peroxidase activity was lowest at 1 d of age and increased over the course of the experiment but was unaffected by treatments (P less than .05). Plasma tocopherol concentration decreased (P less than .01) with time, with E therapy tending to increase tocopherol concentration. Differences in mean plasma tocopherol concentrations among breeds were also observed (P less than .01). Selenium concentration increased over time and with the E injection (P less than .01). An interaction between ewe and lamb Se-E treatments also was observed (P less than .10), with nontreated lambs from nontreated ewes exhibiting lower Se concentrations than treated lambs from injected ewes. An increase in lamb plasma Se concentration was noted in response to Se-E treatments (P less than .001). In the ewes, plasma tocopherol concentration was lower while Se concentration was higher at 18 d than at 1 d postpartum (P less than .01 and P less than .001, respectively). Milk Se concentration was lower at 18 d than at 1 d (P less than .001) and was higher (P less than .10) in Se-E-treated ewes.  相似文献   

7.
Fifty-two Targhee twin-bearing ewes were used in a factorial arrangement of treatments to investigate the role of supplemental vitamin E (vit E); 0 (NE) vs 400 IU of vit E x ewe x (-1)d(-1) (E) and parainfluenza type 3 (PI3) vaccination; none (NP) vs PI3 vaccination (P) in immune function. Parainfluenza type 3 vaccination was used to evoke an immune response. Ewes receiving PI3 were vaccinated at 49 and 21 d before the expected lambing date. Ewes receiving vit E were orally dosed daily, 32 to 0 d before lambing. Blood was collected from ewes at the time of the initial PI3 vaccination and 4 h postpartum. Blood was collected from lambs (n = 104) at 3 d postpartum. Ewe and lamb sera were analyzed for anti-PI3 antibody titers, immunoglobulin G (IgG) titers, and vit E concentrations. Colostrum was collected 4 h postpartum and analyzed for IgG. The model for ewe and lamb analysis included the main effects of vit E and PI3, sex (lambs model only), and their interactions. No interactions were detected (P > 0.20) for any ewe or lamb variables. Serum anti-PI3 titers were greater (P < 0.01) in P ewes and their lambs than NP ewes and their lambs. Serum vit E concentrations were greater (P < 0.01) in E ewes and their lambs than NE ewes and their lambs. Colostral IgG titers and serum anti-PI3 titers did not differ (P > 0.20) between E and NE ewes. Serum IgG titers in E ewes and their lambs did not differ (P > 0.15) from IgG titers in NE ewes and their lambs. Lamb anti-PI3 titers did not differ (P = 0.76) between lambs reared by E and NE ewes. These results indicate that, although supplemental vit E to the ewe increased lamb serum vit E concentration, it had no effect on measures used in this study to assess humoral immunity in the ewe or passive immunity to the lamb.  相似文献   

8.
Our study aimed to investigate responses to supplementation of calcium (Ca), magnesium (Mg) and sodium (Na) to lactating ewes and lambs grazing barley forage from lamb marking to weaning. A 10-ha paddock sown to barley was subdivided into eight plots as four replicates of two treatments. Merino ewes (n = 104) with lambs at foot were stratified to the eight plots (13 ewes and 21 lambs/plot) based on number of lambs (twin or single) and ewes' weight. Supplemented groups had access to mineral supplements (30 g/ewe/day) supplying 12 g/ewe/day ground limestone, 12 g/ewe/day Causmag® and 6 g/ewe/day coarse salt in a ratio of 2: 2: 1 by weight (as fed) from day 0 (a day before lamb marking) after sample collection. Control groups were not supplemented with minerals. Blood, milk and urine samples from ewes and blood from lambs were collected at different time points, namely, a day prior to lamb marking (day 0), 14 days after the commencement of study (day 14), and 28 days after the commencement of study (day 28). Weight of the lambs was also recorded at each time point. We found that the concentration of the forage minerals (Ca, Mg and potassium (K)) was lower on day 28 than on day 0 (P < 0.025). Liveweight gain was greater in the first 14 days compared with the second weight gain period (P < 0.001). The interaction of time and treatment was significant for liveweight (P < 0.001). Due to the improvement in weight gain of supplemented lambs, we recommend that mineral supplementation during late lactation is beneficial considering the low cost of minerals, even though the mineral content of the forage was not deficient.  相似文献   

9.
To investigate the influence of maternal Se supply and plane of nutrition on lamb morbidity, mortality, and passive transfer of IgG, pregnant ewe lambs were used in 2 experiments with 2 × 3 factorial treatment arrangements. Supplementation of Se began at breeding and was either adequate Se (ASe, 9.5 μg/kg of BW) or high Se (HSe, 81.8 μg/kg of BW) in Exp. 1 or ASe (11.5 μg/kg of BW) or HSe (77.0 μg/kg of BW) in Exp. 2. On d 50 or 40 of gestation for Exp. 1 or 2, respectively, ewes were assigned randomly to 1 of 3 nutritional planes: 60% (RES), 100% (control, CON), or 140% (HI) of NRC requirements. This resulted in the following treatments: ASe-RES, ASe-CON, ASe-HI, HSe-RES, HSe-CON, and HSe-HI. Upon parturition, lambs were separated from their dams and serum samples obtained. Lambs were fed artificial colostrum for the first 20 h and then placed on milk replacer and grain pellets until completion of the study (Exp. 1, 57 d; Exp. 2, 21 d). Twenty-four hours after parturition, lamb serum samples were collected for IgG analysis. All lambs were reared similarly and morbidity and mortality assessed. Main effects were considered significant when P ≤ 0.05. In Exp. 1, there was a Se × plane of nutrition interaction (P ≤ 0.01) for lamb morbidity from birth to weaning and for 24-h IgG concentration. Lambs from ASe-RES and HSe-HI ewes were treated more frequently (P < 0.01) for respiratory and gastrointestinal disease, and lambs from HSe-HI ewes had the smallest (P < 0.01) 24-h serum IgG concentration. In Exp. 1, lambs from HI ewes also had the greatest (P < 0.01) mortality rates from birth to weaning compared with lambs from CON and RES ewes. In Exp. 2, there was an effect (P < 0.01) of maternal plane of nutrition with lambs from RES ewes having increased 24-h IgG compared with lambs from CON and HI ewes. There was no effect of maternal Se supplementation on lamb 24-h IgG in Exp. 2; however, there was a Se × plane of nutrition interaction (P < 0.01) for morbidity. From birth to 21 d of age, lambs from ASe-CON ewes had fewer (P < 0.01) treatment days compared with lambs from any of the other treatment groups. There also tended (P = 0.08) to be an effect of maternal Se supplementation on lamb mortality with increased mortality observed in lambs from HSe ewes. Results from the studies show a restricted maternal plane of nutrition can increase lamb serum IgG concentration. Selenium results were not consistent between the 2 experiments and may be due to differences in maternal Se.  相似文献   

10.
贵州典型地区比较适宜于山羊的养殖。通过对放牧肉山羊营养状况的初步调查发现,肉山羊的蛋白质营养水平偏低;在矿物质方面,存在钠的不足,铁、铜处于临界状态,钙、镁、硒、锰、锌则不缺乏。对于快速生长的幼山羊和泌乳母羊也应注意钙的补充。  相似文献   

11.
A growth experiment with 108 lambs (breed German Merino Landsheep) was carried out in order to examine how gender, body weight and feeding intensity affect trace element concentrations in tissues and carcass. The lambs (50% male and 50% female) were fattened at three levels of feeding intensity ('low', 'medium' and 'high' by varying daily amounts of concentrate and hay) and slaughtered at different final body weights (30, 45 or 55 kg). Six male and six female animals were sacrificed at 18 kg live weight at the beginning of the comparative slaughter experiment. The left half carcass of each animal was divided into muscle tissue, fat tissue as well as bones and sinews and analysed for the trace elements copper (Cu), iron (Fe), manganese (Mn) as well as zinc (Zn). The body weight level influenced the Zn concentrations significantly in all tissues. In addition, the Fe concentration in the fat tissue was influenced by the body weight as well as the Cu content in the bone tissue. An influence due to gender could be seen for the Zn concentration in the muscle and fat tissue and for the Fe content in the fat and bone tissue as well as for the Cu concentration in the bones. The feeding intensity affected the Cu content in the muscle and bone tissue and also the Zn content in the muscle tissue. In the present study with lambs at body weight range from 18 to 55 kg on an average, 127 mg Fe, 87 mg Zn, 1.5 mg Cu as well as 1.1 mg Mn per kilogram dry matter were found in the bone tissue. In lamb muscle tissue combined from all parts (body weight range from 18 to 45 kg, both genders) the highest concentrations were for Zn and Fe [3.42 and 1.31 mg/100 g meat (wet weight basis)], while Cu remained far below these levels (0.08 mg/100 g meat and Mn was even below the detection limit of 0.025 mg/kg). Lamb muscle is a valuable source for highly available haem-Fe as well as for Zn and Cu in human nutrition.  相似文献   

12.
Six ewe genotypes, generated by mating Coopworth (C), Polypay (P), and Suffolk (S) rams to P and Coopworth-type (Ct) ewes, were exposed to Hampshire rams for spring lambing from 1987 through 1990. Data from 1,013 exposures and 973 resultant lambings were used to analyze reproductive traits and cumulative ewe productivity over 4 yr. Ewe body and fleece weights were also analyzed. Ewes from S sires weaned the heaviest lambs and ewes from P sires weaned the largest number of lambs, resulting in similar total weight of lamb weaned per ewe mated. Coopworth-sired ewes weaned the least total weight of lamb per ewe mated. Ewes weaning twins produced 54% more total litter weight per ewe than those weaning singles. Annual ewe survival averaged 95%, ranging from 93% for S x P and C x P ewes to 97% for P x Ct and C x Ct ewes. When cumulative number and weight of lamb produced was assessed on the basis of all ewes starting the trial, P-sired ewes were highest, followed in order by daughters of S and C sires. Suffolk-sired ewes (67 kg) were 13% heavier than daughters of P rams and 19% heavier than daughters of C rams. Adjustment of lamb production for ewe metabolic body size resulted in C-sired ewes being more efficient than the heavier S-sired ewes. Coopworth-sired ewes produced 32% more wool than ewes sired by the other two breeds. Differences in wool production between ewes weaning one or two lambs were small.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.
The 4 yr productivity of 25% (QF; n = 533) and 50% (HF; n = 531) Finnsheep ewes exposed to either Suffolk or Columbia rams in one of three production systems was monitored to test the effects of system, terminal sire breed, maternal line, and their interactions on annual market lamb production. Ewe lambs and yearlings were randomly assigned to either a high-input accelerated lambing system (HIGH), a high-input annual system (MED), or a low-input annual system (LOW). Nursery facilities were available for weak lambs or those born in triplet or more births for the HIGH and MED but not for the LOW systems. Accelerated lambing protocol required early weaning. Sex-adjusted lamb weaning weights were corrected to within-system mean ages of 42 d for HIGH and 70 d for MED and LOW. The HIGH ewes weaned 1.55 lambs per year compared with 1.46 for MED and 1.18 for LOW (P less than .01). However, because of early weaning, HIGH yielded the lowest weight of weaned lamb per year. The MED ewes weaned 5.9 and 11.1 more kilograms of lamb per year than the LOW and HIGH ewes, respectively (P less than .01). The HIGH system may be economically feasible if young lambs could be inexpensively grown to feeder or market lamb weight. The HIGH ewes did not, however, increase lamb numbers in proportion to increased exposures compared with the annual systems. Breed-group effects for ewe productivity (kilogram of lamb weaned per ewe per year) were consistent across management systems, although some interactions among breed group and system were present for components of productivity. Suffolk rams yielded an advantage of 1.6 kg of weaned lamb per exposure over Columbia rams (P less than .05) due to a 3% better lamb survival (P less than .01) and heavier weaning weight, especially in the LOW system. The HF ewes weaned .1 more lambs per exposure than QF ewes (P less than .01); .06 of the lambs were nursery-reared. However, lambs from HF ewes had a 2% lower survival rate (P less than .05) and were 1.4 kg lighter at weaning (P less than .01), so overall productivity among HF and QF ewes was similar.  相似文献   

14.
Seventy-two Rambouillet ewes were fed one of two different levels of energy and protein during gestation to determine the effects of maternal undernutrition on growth and development in their offspring. Levels of energy and protein for the two groups of ewes were: 70% of National Research Council (NRC) requirements 30 d prior to breeding and the first 100 d of gestation and then alfalfa hay fed at 70% of the average consumed by group 2, and 100% of NRC requirements 30 d prior to breeding and throughout gestation. Dissection data from the leg and muscle characteristics were recorded for each lamb. Neither dissected muscle and fat percentages nor proximate analyses of dissected muscles was influenced by ewe undernutrition during early pregnancy. However, the reduced conception rate, increased embryonic/fetal mortality, decreased birth weights and increased lamb mortality resulted in a severe reduction in kilograms of lamb per ewe bred. Feeding ewes 70% of NRC requirements during gestation resulted in lambs with heavier semitendinosus muscle weights, larger muscle fiber diameters and shorter sarcomere lengths than in lambs from adequately fed ewes. No influence of ewe diet, birth type or sex was observed for proportions of muscle fiber type (beta R, alpha R or alpha W). Therefore, low level feeding of ewes during early gestation had no detrimental effects on the carcass or muscle fiber characteristics of their lambs at slaughter.  相似文献   

15.
This study was conducted to evaluate vitamin E injection and Se in a mineral supplement in late gestation on lamb survival and pre-weaning growth performance. Ewes were grouped in pens based on their fetal count and BW. The feed provided to ewes in late gestation included alfalfa hay, corn, and protein supplement according to NRC (1985) recommendations. Ewes in late gestation were assigned to a 2 × 2 factorial arrangement of treatments within fetal count (single, twin, and triplet + quad). Treatments were no vitamin E or 900 IU of vitamin E injected i.m. per week and 10 or 90 ppm of Se in a mineral supplement fed ad libitum. Within each pen of ewes (8 to 10 head), approximately one-half of the ewes received injectable E beginning 4 wk before the first expected lambing; the other one-half received no vitamin E. Vitamin E treatments ended at lambing time; however, ewes remained on their respective mineral sources during lactation. Lambs were provided access to creep (16% CP, 83% TDN, and fortified with 35,000 IU of vitamin E, 0.27 g of Se, and 50 g of chlortetracycline/909 kg of creep feed) initiated at an average 10 d of age to weaning. Weekly injection of 900 IU of vitamin E did not affect birth BW (BBW) of lambs. However, 90 ppm of Se fed ad libitum improved BBW of lambs (5.06 vs 4.88 kg, P<0.10) with all of the improvement occurring in lambs born to 6- to 7-yr-old ewes (P<0.01). Vitamin E increased (P<0.05) the pre-weaning performance of lambs from 1- to 2- and 6- to 7-yr-old ewes but did not improve the performance in lambs from 3- to 5-yr-old ewes. Multiple-birth lambs from ewes treated with vitamin E had increased survival in 1 of 2 experimental yr (P<0.05). Survival of single-birth lambs was not effected by vitamin E or Se treatment. These results demonstrate that supplementation of 90 ppm of Se fed ad libitum to ewes during late gestation and throughout lactation improved BBW of lambs from 6- to 7-yr-old ewes, and weekly injection of 900 IU of vitamin E to ewes during late gestation increased the pre-weaning growth of lambs from 1- to 2- and 6- to 7-yr-old ewes and may increase the survival of multiple-birth lambs.  相似文献   

16.
The transference of immunoglobulins from six New Zealand Romney ewes to their lambs was examined. Immunoglobulin levels were determined in ewe plasma, colostrum and lamb plasma shortly after birth and before the lambs fed, in lamb plasma 2 days after birth, and lamb plasma, ewe plasma and milk 30 days after parturition. Levels of total IgE, and IgE, IgG1, IgG2, IgM, and IgA with specificity for Trichostronglus colubriformis third stage larval secretory/excretory products (TcL3E/S) were determined. Mean levels of total IgE were three times higher in colostrum than in parturient ewe plasma while only trace amounts were detected in milk at 30 days after birth (107.7, 34.3, and 0.2U ml(-1), respectively, differences between means P< or =0.01). Mean total IgE in lamb plasma rose from being undetectable before suckling to levels comparable to those of the ewes by 2 days after birth (21.7U ml(-1)) and then declined to low levels by 30 days (0.4U ml(-1)). Total IgE levels in lamb plasma were significantly correlated with levels in ewe plasma and colostrum (r=0.91, P< or =0.01; r=0.96, P< or =0.003, respectively). The transference of TcL3E/S-specific IgE, IgG1 and IgA was substantial with mean levels of these antibodies in lamb plasma at 2 days comparable to that in parturient ewe plasma (absorbance levels in lamb plasma of 0.283, 0.537, and 0.334, respectively). Proportionally less maternal IgM and IgG2 appeared to be transferred to the lambs (absorbance of 0.112 and 0.081, respectively). Levels of TcL3E/S-specific IgE and IgG1 in lamb plasma at 2 days were significantly correlated with levels in parturient ewe plasma and colostrum (r=0.89 and 0.82, 0.85 and 0.96; all P< or =0.05, respectively). These results indicate that IgE is concentrated in ewe colostrum and that substantial amounts of maternal IgE are transferred to lambs via colostrum. Further, the results suggest that humoral immunity against gastro-intestinal nematode parasites and potentially other parasites in colostrum-fed lambs may approximate that of the ewe. The implications of the transference of humoral immunity through colostrum in ruminants for the passive protection and the development of active immunity against parasites remains to be fully explored.  相似文献   

17.
Objectives of this study were to estimate the magnitude of the effects of various factors associated with ewes and their ram lamb mates on fertility, prolificacy, lamb survival, lamb weaning weight and ewe productivity and to estimate the heritability and repeatability of each trait. Records from 731 ewe-years, 75 ram lamb sires and 616 lambs born from the University of Illinois Rambouillet flock were used. Ewes mated to single-born ram lambs had higher fertility rates (P less than .01), gave birth to lambs with higher survival rates (P less than .01), weaned lighter (P less than .05) individual lambs but weaned more weight of lamb per ewe exposed (P less than .01) than ewes mated to multiple-born ram lambs. Ram lamb breeding weight, ram lamb scrotal circumference, ewe breeding weight and ewe age had relatively large and positive effects on the composite trait of weight of lamb weaned per ewe exposed and significant effects on a number of the component traits. Heritability and repeatability estimates were, respectively, as follows: fertility, 3%, 3%; prolificacy, 34%, 19%; lamb survival, 15%, 8%; lamb weaning weight, 7%, 36%; and ewe productivity, 27%, 10%.  相似文献   

18.
A 3-yr study was conducted to comprehensively evaluate columbia, suffolk, usmarc-composite (composite), and texel breeds as terminal sires in an extensive rangeland production system. The objective was to estimate breed-of-ram effects on ewe fertility, prolificacy, and dystocia, and sire breed effects on lamb survival and growth until weaning at approximately 132 d of age. Data were from 22 columbia, 22 composite, 21 suffolk, and 17 texel rams with 957 exposures to 574 adult rambouillet ewes (3- to 7-yr-old at lambing), 908 lambings, and 1,834 lambs. Ram breed did not affect ewe fertility (mean = 94.9%; p = 0.73), total number born per ewe lambing (mean = 2.02 lambs; p = 0.20), number born alive per ewe lambing (mean = 1.90 lambs; p = 0.24), or number weaned per ewe lambing (mean = 1.45 lambs, p = 0.94). Dystocia rates were different (p = 0.01) for ewes mated to columbia (12.2%), composite (13.5%), suffolk (25.7%), and texel rams (31.9%) during 1 yr of the study, but differences among ram breeds were not repeatable (p ≥ 0.38) during the other 2 yr. Suffolk-sired lambs were heavier (p ≥ 0.02) at birth (5.5 kg) and weaning (40.3 kg) than lambs sired by the other breeds, which did not differ (p ≥ 0.34) for birth weight (mean = 5.3 kg). Texel-sired lambs (37.4 kg) were lighter (p ≥ 0.02) at weaning than columbia- (38.8 kg) and composite-sired (38.4 kg) lambs, which did not differ (p = 0.40) for weaning weight. Sire breed effect approached significance (p = 0.06) for lamb survival to weaning; estimated survival probabilities were 0.87 (columbia), 0.89 (composite), 0.93 (suffolk), and 0.86 (texel) for lambs reared by their birth dam. Interaction between sire breeds and birth weight affected (p < 0.001) lamb survival and revealed that lightweight columbia- and suffolk-sired lambs had a greater risk of death than lightweight lambs sired by composite and texel rams, but risk of death did not increase substantially for heavyweight lambs from any of the breeds. When mated to adult rambouillet ewes in an extensive rangeland production system, the use of suffolk rams is warranted to improve preweaning growth of market lambs and is not predicted to affect ewe fertility, ewe prolificacy, dystocia, or lamb survival compared with the other sire breeds we tested.  相似文献   

19.
Abstract

AIMS: To measure the magnitude and variability in production responses to anthelmintic treatments administered to adult ewes around lambing.

METHODS: Ewes carrying twin lambs, from sheep and beef farms (eight in Year 1 and six in Year 2) in the Wairarapa region of New Zealand, were enrolled in 14 trials (part of an experiment carried out on one farm in one year). Experiment 1 compared ewes treated 2–4?weeks pre-lambing with a controlled release capsule (CRC) containing abamectin, albendazole, Se and Co, to ewes injected pre-lambing with a long-acting Se plus vitamin B12 product, and to untreated ewes. Experiment 2 included these treatments, plus a CRC administered at pregnancy scanning. Experiment 3 included the same treatments as Experiment 1, plus administration of a CRC containing albendazole, Se and Co, injectable moxidectin or oral derquantel plus abamectin, all administered pre-lambing, or oral derquantel plus abamectin administered 4–6?weeks after lambing. Variables compared were ewe liveweight at weaning and pre-mating, lamb liveweight at weaning, total weight of lamb weaned per ewe and ewe dag score at weaning.

RESULTS: Ewes treated with a CRC pre-lambing were heavier than untreated ewes (mean 3.2?kg) at weaning in 12/14 trials, and pre-mating (mean 2.8?kg) in 9/14 trials (p<0.001). Compared with mineral-treated ewes the mean difference was 2.8?kg pre-lambing (9/14 trials) and 1.7?kg pre-weaning (6/14 trials). Lambs reared by treated ewes were heavier (mean 1.55?kg) at weaning in 6/14 trials (p<0.001), but there was no effect of CRC treatment on total weight of lambs weaned per ewe (p=0.507). Variation in weight of lamb weaned per ewe was largely explained by differences in lamb survival from birth to weaning (p<0.001), with no effect of CRC treatment (p>0.65).

Treatment of ewes with a CRC at pregnancy scanning was neither better nor worse than a pre-lambing treatment (p=0.065).

There was no difference in the response from treatment with either of the two CRC or moxidectin. Treatment with short-acting oral anthelmintics resulted in no consistent benefit.

CONCLUSIONS: Anthelmintic treatments administered to ewes around lambing resulted in variable responses between farms and years, which in some trials were negative for some variables, and some of the variability was due to the mineral component of the CRC. The widespread perception amongst farmers and veterinarians that anthelmintic treatment of ewes around lambing will always result in positive benefits is not supported.  相似文献   

20.
滩羊土——草——畜系统中的微量元素及其意义   总被引:2,自引:0,他引:2  
甘肃景泰滩羊典型产区草地土壤中含有Be、Pb、Ti、Ba、Mn、Ga、Cr、Ni、V、Cu、Zr、Co、Sr、Y、Yb等15种微量元素。草地混合牧草吸其中的13种,其中Yb显著减少,缺少了Be和Co。羊毛中微量元素的种类和含量变化很大并且复杂。滩羊成年母羊毛中只含Pb、Ti、Mn、Cu等4种元素,而二毛期即1月龄羔羊毛中含有Ba、Pb、Ti、Mn、Cr、Ni、Cu、Zr、Ag、Zn、Sr、Mo和Y  相似文献   

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