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1.
妊娠期肝内胆汁淤积症(Intrahepatic cholestasis of pregnancy,ICP)是孕妇在妊娠晚期出现的以瘙痒和黄疸为特征的肝病,是一种高危产科疾病,严重影响胎儿的健康.为了更好地研究ICP的发病机制,本试验以妊娠母羊为动物模型,分别通过大剂量(2 mg/kg)和小剂量(1.1 mg/kg)的胆酸盐静脉灌注怀孕后期的母羊,同时进行胎儿血管造瘘手术,目的是研究ICP的发病模型和胆酸对胎儿和新生儿的影响机制.结果显示,给妊娠母羊大剂量多次静脉灌注胆酸盐,引起母体难产,导致胎儿宫内窘迫和死亡;小剂量灌注,导致胎儿的低出生重,但胎儿在出生后15 d时,羔羊的体质量与正常的羔羊没有差异,体现了追赶生长的特性.结果表明以妊娠母羊为动物模型,通过静脉灌注胆酸盐可以作为研究妊娠期肝内胆汁淤积症的疾病模型,为进一步探索ICP发病时胆酸对胎儿的影响机制提供实验依据.  相似文献   

2.
Autopsies were performed on lamb carcases from 2 groups of Merino ewes lambing in paddocks in spring 1978 and from 1 group lambing in pens in 1980 in southwest Queensland. These showed that the main causes of death were starvation due to failure of the lamb to obtain milk, problems at parturition causing death during or shortly after birth and, in some cases, predation. The majority of lambs died within 1 week of birth with the highest mortalities occurring in the lighter lambs. In the pen study, mean birth weight of lambs that died was 3.0 (s.d. = +/- 0.5) kg. The mean daily weight loss of lambs that died of starvation in the pens was 0.22 kg and the mean loss to autopsy was 0.35 kg. In the pen study, there were more lamb deaths, deaths from starvation, mismothering and desertion in each of 2 groups fed a below maintenance ration than in an above maintenance group. More lambs died and more lamb deaths were due to starvation in a group with unsound udders than in a sound udder group. The results are similar to those found by workers investigating perinatal lamb mortality in other areas. Their significance is discussed in relation to Merino sheep flocks in southwestern Queensland.  相似文献   

3.
Sixteen lambs exhibiting hepatogenous photosensitization (alveld) after grazing pasture containing Narthecium ossifragum and seven nonphotosensitized lambs grazing the same pastures were studied. All the alveld-affected lambs revealed liver damage dominated by single cell necrosis, portal fibroplasia and bile duct proliferation. Crystalloid clefts were demonstrated in the bile ducts of two and in the hepatocytes and Kupffer cells of nine photosensitized lambs. Plasma bilirubin concentration was severely increased in ten of the cases of alveld whereas the activity of aspartate aminotransferase was moderately to severely increased in seven cases. The activity of glutamate dehydrogenase was moderately elevated in one of the photosensitized lambs. The main histopathological findings in the kidneys from the alveld-affected lambs were dilated tubules, often with eosinophilic material in the tubular lumina. Regenerative changes were seen in a large proportion of the renal sections. Elevated plasma concentrations of urea and creatinine, and the renal histopathological changes, suggested that the photosensitized lambs had been through a phase of renal injury. Analysis of the free and conjugated sapogenin content in liver tissue and bile was performed by gas chromatography–mass spectrometry. There were significantly higher concentrations of conjugated episapogenins in both the liver and bile in the alveld-affected lambs than in the nonphotosensitized lambs.  相似文献   

4.
AIMS: To determine the effects of liveweight and condition score of ewes at mating, and shearing mid-pregnancy, on birthweights and growth rates of twin lambs from birth to the time of weaning, and; to determine whether any effect of condition score is independent of liveweight.

METHODS: Romney ewes (n=435) which conceived within a 17-day mating period and successfully gave birth to and reared twin lambs to weaning were used. Ewes were managed during pregnancy so that their total liveweight increased at a level equivalent to the expected growth of the conceptuses. Approximately half of the ewes were shorn 70 days after the mid-point of mating, and the remainder were left unshorn, at which time they had 6-months' wool growth. All lambs were weighed within 12 h of birth and again at weaning.

RESULTS: There was a significant linear relationship (R2=0.99) between mean group liveweight and condition score of ewes at mating (difference of 7.3 kg per 1.0 unit condition score). Liveweight of ewes at mating had small but significant (p<0.05) positive effects on both birthweights and growth rates of twin lambs to weaning. Ewes that had condition scores of 3.5–4.0 (scale 0–5) at mating gave birth to significantly (p<0.05) lighter lambs than ewes that had condition scores <3.5. The condition score of ewes at mating was positively associated with growth rates of lambs, although this effect was largely explained by variation in the liveweight of ewes at mating.

Twin lambs born to ewes shorn mid-pregnancy were significantly (p<0.05) heavier at birth (by 0.4 kg) and at weaning (p<0.05) than those born to unshorn ewes. The heavier weaning weights of lambs born to ewes shorn mid-pregnancy were due to a heavier birthweights rather than increased growth rate.

CONCLUSIONS: Liveweight and condition score of ewes at mating had small positive effects on growth rates to weaning of twin lambs. Shearing mid-pregnancy increased birthweights and weaning weights of twin lambs. To achieve high weaning weights of twin lambs, farmers should ensure ewes attain high liveweights and condition scores at mating and shear mid-pregnancy. It is speculated that the effects of liveweight and condition score of ewes at mating on weaning weights of twin lambs would be greater than those observed in the present study under conditions in which nutrition of the dam is below optimum.  相似文献   

5.
Growth and carcass characteristics of lambs sired by Dorper and Dorset rams   总被引：1，自引：0，他引：1  
Growth and carcass merit of Dorset-(DO) and Dorper-sired (DP) lambs were compared over 3 yr in matings with 50% Dorset, 25% Rambouillet, 25% Finnsheep ewes. The DP were slightly lighter (P = 0.09) at birth than the DO lambs. In the first year of the study, DP lambs produced by AI using imported South African sires were heavier than DO lambs when weaned at 60 d of age (21.7 vs. 19.5 kg; P = 0.05). In yr 2 and 3, however, offspring of natural-service Dorper sires produced in the U.S. did not differ in weaning weight from DO lambs (16.9 vs. 17.8 kg; P = 0.02 for breed x year interaction). Lamb survival was also affected by breed x year interaction (P = 0.04). In 2000 and 2001, with 12 to 16% triplet or larger litters, mortality was higher for DP lambs (14.9 vs. 7.7%; P = 0.12). However, in 2002, with approximately 33% triplet or larger litters and with higher mortality levels in all birth types, DP lambs had fewer death losses than did DO lambs (23.2 vs. 36.1%; P = 0.11). No differences between DO and DP lambs were observed in postweaning gain during summer grazing or in drylot in autumn. At chilled carcass weights of approximately 25 kg, DP lambs were somewhat fatter than DO lambs, with greater body wall thickness (P < 0.01; 22 vs. 19 mm) and slightly greater backfat thickness (P = 0.15; 6.4 vs. 5.5 mm) and yield grades (P = 0.15; 2.9 vs. 2.6). The DP lambs also had more desirable leg scores (P = 0.01; 11.6 vs. 10.9) and slightly larger LM area (P = 0.13; 14.1 vs. 13.5 mm2) than did DO lambs, confirming acceptable muscling and conformation in carcasses from Dorper-sired lambs. However, differences were not observed in the percentage of carcass weight in the leg or loin, or in the lean:bone ratio in the dissected leg. Ultrasonic measurements of backfat thickness and LM area taken in live lambs before slaughter were positively associated with direct measures on chilled carcasses with correlations of 0.77 for backfat thickness and 0.51 for LM area.  相似文献   

6.
The use of terminal sires (TS) for crossbreeding is integral to the UK sheep industry where approximately 71% of market lambs are sired by TS rams. Early growth of these crossbred lambs affects profitability. The objectives of this study were i) to evaluate the effectiveness of index selection among TS on BW and ADG of their crossbred offspring; and ii) to compare the efficacy of that selection within TS breeds. The most widely used TS breeds in the United Kingdom are Charollais, Suffolk, and Texel. These participated in sire referencing schemes in which they were evaluated on a lean growth index designed to increase carcass lean weight at a given age. From 1999 to 2002, approximately 15 high and 15 low lean growth index rams per breed (93 in total, differing in index on average by 4.6 SD) were selected from within their sire referencing schemes and mated to Welsh and Scottish Mule ewes. Their crossbred offspring were reared commercially on 3 experimental farms in England, Scotland, and Wales. A total of 6,515 lambs were born between 2000 and 2003. Lambs were weighed at birth (BWT), 5 wk (5WT), and 10 wk (10WT), and their ADG from birth to 10 wk was calculated. Lambs sired by high index rams were on average, across breeds, heavier at all ages (P < 0.01) with 0.07 ± 0.03, 0.3 ± 0.1, and 0.4 ± 0.1 kg greater BWT, 5WT, and 10WT, respectively. Their ADG was 5.1 ± 1.9 g/d greater than low-index-sired lambs (P < 0.01). Suffolk-sired lambs were on average heavier at all ages, with greater ADG, whereas Charollais-sired lambs were lightest with smallest ADG. Overall, there was no significant interaction between sire index and sire breed (P > 0.10). Within Suffolk-sired lambs, there was little difference between high and low index sires for the traits studied (P > 0.3). High and low index Charollais-sired lambs differed in BWT (0.09 ± 0.04 kg) and 5WT (0.3 ± 0.1 kg), and Texel-sired lambs differed in 5WT (0.5 ± 0.1 kg), 10WT (0.9 ± 0.2 kg), and ADG (10.2 ± 3.3 g/d; P < 0.01). Lambs from Scottish Mule dams were heavier, with greater ADG, than lambs born to Welsh Mules (P < 0.01). Lambs reared in Scotland were heavier at all ages (P < 0.01). The results suggest that using index selection in TS can improve the growth of their commercial offspring reared on grass.  相似文献   

7.
Objective To investigate the effects of age at castration on the subsequent behavioural response to tail docking. Study design Randomised prospective blinded experimental study. Animals Forty‐five male lambs were admitted to the study at birth. Methods The lambs were allocated into two groups for castration by rubber ring at 1 (1D, n = 20) or 10 (10D, n = 25) days of age. Following castration both groups of lambs were tail‐docked by rubber ring at between 26 and 34 days of age. Their behavioural responses to tail docking were recorded by video for 30 minutes before (n = 11) and 30 minutes after (n = 45) tail docking. Statistical differences were tested using anova with Mann‐Whitney post‐hoc testing. Results Two data sets were removed resulting in n = 19 and = 24 at 1D and 10D, respectively. A significant increase in the incidence of active and abnormal postural behaviour was seen in both groups after tail docking. Three behaviours were significantly different (p < 0.05) between the two groups. These behaviours were rolling, standing unsteadily and the total proportion of time standing with abnormal posture. These behaviours all had greater incidence in the lambs castrated at 1D of age. Conclusions Lambs castrated at 1D appeared to perceive a greater intensity of pain after subsequent tail docking than lambs castrated at 10D. Clinical relevance The timing of a single noxious stimulus in young animals can affect subsequent pain perception.  相似文献   

8.
The mating and lambing records for 1964–1972 of a Romney stud that had been experiencing a serious dystocia problem were investigated. Until 1970 between 20 and 31% of ewes required assistance at lambing but this level then fell to 18% in 1971, 11% in 1972, 3.3% in 1973 and 4.0% in 1974. The decline in dystocia evident in the latter years of the investigation is considered to have been brought about largely by the culling of ewes that were repeatedly assisted at parturition and by the selection of rams that sired lambs of lower birth weight.

Dystocia in this flock was highly correlated with the mean birth weight of single lambs ( r =0.84, p<0.01). Fifty nine percent of assisted single lambs were males; ram lambs were heavier at birth than ewe lambs. Apart from the year 1966, primiparous ewes required no more assistance than older ewes and, except for that year, ewes bearing singles required the same levelof assistance as those bearing twins.

An effect of the sire on the incidence of dystocia was demonstrated for four of the eight lambings studied and was related to the birth weight of the lambs. Thirty four percent of ewes that had been assisted to lamb once had to be assisted again the following year as compared with a 16% assistance rate necessary for those ewes that had not been helped at the previous lambing, thus establishing a high level of repeatability for the condition (p<0.001).  相似文献   

9.
Over 3 yr, postweaning growth patterns and changes in ultrasonic measurements of fat depth (FD) and LM area were assessed for 1,049 crossbred ewe and wether lambs (Ovis aries) produced by mating adult Rambouillet ewes to 1 of 22 Columbia, 22 USMARC-Composite (Composite), 21 Suffolk, or 17 Texel rams and raised to weaning under extensive Western rangeland conditions. After weaning, lambs were transitioned to a high-energy finishing diet in a feedlot, weighed weekly for 13 to 16 wk, and scanned using ultrasound at 2-wk intervals to estimate FD and LM area between the 12th and 13th ribs. Lambs sired by Suffolk rams were 5 to 12% heavier (P < 0.05) at start of test, grew 14 to 22% faster (P < 0.001), and were correspondingly 7 to 14% heavier (P < 0.001) after 90 d on test than lambs sired by rams of the other 3 breeds. At this time, lambs sired by Texel rams were 5% lighter (P < 0.01) than Columbia- or Composite-sired lambs, which did not differ (P > 0.20). Columbia-sired lambs had less FD (8.9 mm) but smaller LM areas (15.6 cm(2)) at 90 d on test (both P < 0.01) than lambs sired by rams of the other breeds (average of 9.8 mm for FD and 16.6 cm(2) for LM area), which did not differ for either measurement at this time. At 60 kg, predicted FD differed among sire breeds (P < 0.001) and were similar for Suffolk- (7.6 mm) and Columbia-sired (7.9 mm) lambs, intermediate for Composite-sired lambs (9.1 mm), and largest for Texel-sired (10.1 mm) lambs. At a BW of 60 kg, LM area differed between all pairs of sire breeds (P < 0.05), and was largest for Texel-sired lambs (16.7 cm(2)), followed by Composite-, Suffolk-, and Columbia-sired lambs (15.7, 14.8, and 14.5 cm(2), respectively). At a predicted FD of 9.1 mm (the boundary between U.S. Yield Grades 3 and 4), the predicted LM area for Suffolk-sired lambs (16.2 cm(2)) was similar (P > 0.10) to that of Texel-sired lambs (16.0 cm(2)) and superior (P < 0.01) to that of Composite- (15.7 cm(2)) and Columbia-sired lambs (15.4 cm(2)). Lambs sired by Suffolk rams were thus equal or superior to lambs sired by the other 3 breeds in growth, FD, and LM area at comparable ages, fatness at 60 kg, and LM area at a FD of 9.1 mm, but inferior in LM area to Texel- and Composite-sired lambs at comparable BW.  相似文献   

10.
To survive, the newborn lamb must be able to maintain body temperature and to stand and move to the udder to suck colostrum to fuel heat production. The objective of this study was to investigate whether neonatal lambs showing slow behavioral progress to standing and sucking also have an impaired ability to maintain body temperature. The time taken to stand and suck after birth, rectal temperatures, and blood samples were collected from 115 newborn single, twin, and triplet lambs of 2 breeds, Scottish Blackface and Suffolk, which are known to show variations in their neonatal behavioral progress. Blood samples were assayed for thyroid hormones, known to be involved in heat production, and cortisol, which plays a role in tissue maturation before birth. In addition, colostrum samples were collected from the 56 ewes that gave birth to the lambs, and assayed for protein, fat, and vitamin contents. Heavy lambs (more than 1 SD above the breed mean), Blackface lambs, and singleton or twin lambs were quicker to stand and suck from their mothers than lightweight (more than 1 SD below the breed mean), Suffolk, or triplet lambs. Low birth weight lambs also had lower rectal temperatures than heavier lambs (P < 0.01), as did Suffolk compared with Blackface lambs (P < 0.001). Lambs that were slow to suck after birth had lower rectal temperatures than quick lambs, and this difference persisted for at least 3 d after birth. Within breed, heavy lambs had greater plasma triiodothyronine and thyroxine immediately after birth than light lambs. Blackface lambs had greater plasma triiodothyronine and thyroxine than Suffolk lambs but tended to have less cortisol. Colostrum produced by Blackface ewes had a greater fat content than that of Suffolk ewes (P < 0.001). Thus, lambs that are behaviorally slow at birth are also less able to maintain their body temperature after birth. Although part of their lower body temperature might be attributable to behavioral influences on thermoregulation, the data also suggest that physiological differences exist between these animals. These differences may be related to different degrees of maturity at birth.  相似文献   

11.

This trial evaluated the individual and interactional effects of diet and type of pregnancy (twin or single) on plasma metabolic response in ewes and their lambs from late pre-partum to late post-partum. Thus, a flock of 18 Ile de France breed sheep, consisting of 8 twin-bearing and 10 single-bearing ewes, were allocated to one of two groups according to their diet, either based on ad libitum naturalized pasture hay (NPH) or red clover hay (RCH), from d 45 pre-partum to d 60 post-partum. Plasma samples were collected at different times to determine albumin, cholesterol, total protein and urea, plus glucose and β-hydroxybutyrate (BHB) concentration in ewes. The data was processed using the lme4 package for R, and SPSS Statistics 23.0 for Windows. The results showed that both diet and type of pregnancy influenced the metabolic profile in ewes, showing an inverse relationship between single- and twin-bearing ewes regarding glucose and especially BHB proportions from pre-partum to birth. During post-partum, higher urea concentrations were observed in twin- and single-bearing ewes fed RCH in contrast to those fed NPH, as a result of the higher-quality forage offered to ewes. Regarding lambs, the diet and type of pregnancy influenced the total protein and urea levels, where an inverse relationship at birth and early post-partum between albumin and cholesterol vs. total protein and urea was detected, reflecting a trend (P value between 0.06 and 0.07) to a better performance by groups of single lambs, especially those from single-bearing ewes fed RCH. Finally, under the conditions of this study, the maternal diet and type of pregnancy influenced the plasma metabolic response in ewes and their lambs, affecting the lamb performance especially at birth.

  相似文献   

12.
Cystic follicle is anovulatory follicular structure that is caused by an endocrine imbalance. The activity of cytochrome P450‐side chain cleavage (P450scc) is essential for the initiation of steroidogenesis in the follicle. The present study was designed to compare the frequency of cells containing P450scc between healthy and atretic small antral follicles, and among several types (I, II and III, classified based on the presence of granulosa layer) of cystic follicles. Paraffin sections of healthy (2–5 mm in diameter), atretic (2–5 mm) and cystic follicles (>25 mm) were immunohistochemically stained with rabbit polyclonal antibody to bovine P450scc. The P450scc‐positive cells were counted in four different regions of the follicles from the apical to the basal side. In small antral follicles and cystic follicles, P450scc‐positive cells were localized in the theca interna layers but not granulosa layers. The P450scc‐positive cell populations decreased in the late atretic follicles compared with the early and advanced atretic follicles at all the regions of follicle. Type III cystic follicles showed significantly lower frequencies of P450scc‐positive cells than those in the types I and II cystic follicles. These results suggest that in both small and cystic follicles in cows, total loss of granulosa cells may be associated with the reduction of frequency of P450scc‐positive cells in theca interna layer.  相似文献   

13.
黄厚才 《畜牧与兽医》1996,28(6):245-246
选择新西兰母兔１０只，于交配前后及妊娠不同时期采血，测定ＬＨ、雌二醇（Ｅ２）、孕酮（Ｐ）浓度。结果显示：ＬＨ水平在交配前４小时为１８．０２±３．０５ｎｇ／ｍｌ，交配后４小时达４３．１４±８．７５ｎｇ／ｍｌ，交配后８小时达高峰水平１６５．１２±２６．４３ｎｇ／ｍｌ，是交配前９倍，其后逐渐降至交配前水平。Ｅ２浓度在交配前５天时为４２．５±１０．１ｐｇ／ｍｌ，交配前４小时为６８．７±１２．１ｐｇ／ｍｌ，交配后４小时为１１３．１±１３．７ｐｇ／ｍｌ，交配后８小时为１１８．５±１５．４ｐｇ／ｍｌ，其后渐降。孕酮浓度在受孕后逐步升高，交配前４小时至交配后２天，孕酮水平在１．０ｎｇ／ｍｌ左右，交配后第２天时，Ｐ水平为１．１２±０．５３ｎｇ／ｍｌ，而在交配后第３～８天时，Ｐ水平达３．８２±０．７２～１０．１０±２．３４ｎｇ／ｍｌ，是交配前后的３～１０倍，交配后第２１天，Ｐ水平为１８．９４±３．９８ｎｇ／ｍｌ，交配后２９天为４．０２±１．０５ｎｇ／ｍｌ。因此，家兔通过交配刺激排卵，也伴有ＬＨ峰值。交配３天后，Ｐ水平大幅度提高，表明家兔妊娠也需要高水平孕酮，同时也为通过测定Ｐ水平进行家兔早期妊娠诊断提供理论基础  相似文献   

14.
This study evaluated the influences of carprofen and the experience of the surgeon on post‐castration pain in lambs and young sheep castrated in the field. A total of 201, 1–6‐week‐old lambs with a mean body mass of 11.0 ± 2.4 kg (mean ± SD) were castrated after local application of 4 mL lidocaine (2%). Preoperatively lambs were given either 20 mg carprofen SC or an equal volume of saline in a randomized order. A further 34 sheep, aged 6 months, with a mean body mass of 36.0 ± 4.5 kg were castrated after local application of 7 mL lidocaine (2%). Preoperatively sheep received 2 mg kg?1 carprofen SC or an equal volume of saline in a randomized order. Lidocaine was injected SC in front of, behind and into each spermatic cord. All surgery was performed using the same Burdizzo clamp (jaw 45 mm wide, handles 225 mm) either by students or experienced veterinary surgeons. Pain was assessed preoperatively and at 24, 48 and 72 hours after castration by two independent observers unaware of the treatment group. Observers scored pain using a visual analog scale (100 mm) after applying gentle pressure onto the scrotal region ( Thornton & Waterman‐Pearson 1999 ). Swelling of the scrotal region was scored as ‘severe’, ‘present but not severe’ and ‘not present’. The VAS scores were compared using a Mann–Whitney test, p < 0.05 was considered significant. Swelling was compared using Fisher's exact test. In lambs, no significant differences in pain scores between those treated with carprofen or saline were noted by either observer (p > 0.48) at any of the three assessment times. However, the number of lambs with severe or present swelling of the scrotal region was significantly lower in those receiving carprofen (8% versus 18%, p = 0.028). Lambs castrated by students showed significantly higher pain scores (23% versus 13%, p < 0.001 at 24 hours; 20% versus 13%, p = 0.0062 at 48 hours; 16% versus 10%, p = 0.0088 at 72 hours) and significantly more swelling (18% versus 8%, p = 0.0189) of the scrotal region than those castrated by veterinary surgeons. Young sheep receiving carprofen preoperatively had significantly lower pain scores (12 mm versus 25 mm, p = 0.037) 24 hours after surgery compared to sheep receiving saline. No scrotal swelling was obvious in sheep. Juvenile sheep but not lambs, receiving carprofen preoperatively showed reduced pain scores up to 24 hours after surgery. Carprofen reduced swelling of the scrotum in lambs. Lambs castrated by experienced surgeons scored lower VAS scores at all times and showed less swelling of the scrotal region.  相似文献   

15.
An antibiotic with a product licence limited to the treatment and control of infectious bacterial enteritis associated with Escherichia coli in piglets was tested for its ability to control watery mouth disease in neonatal lambs. Three groups of lambs were kept in conditions commonly encountered in intensive lambing systems, where high levels of environmental bacterial contamination may be expected. They were allocated at birth to: a control group (group 1) consisting of 18 colostrum-deprived lambs; group 2, consisting of 17 lambs given one feed of colostrum when they were two hours old; and group 3, consisting of 18 colostrum-deprived lambs given spectinomycin orally when they were two hours old. Nine group 1 lambs became diseased and were killed for humane reasons. Blood biochemical changes included hyperglycaemia followed by hypoglycaemia, lactacidaemia, hypoproteinaemia and metabolic acidosis, and postmortem examination of the diseased lambs showed signs consistent with endotoxaemia and a clinical diagnosis of watery mouth disease. Coliforms were isolated from the blood of all group 1 lambs and from half the lambs in groups 2 and 3, but endotoxaemia and watery mouth disease occurred only in group 1 lambs. The results for groups 2 and 3 showed that neither colostrum nor antibiotic at the rates and frequency used prevented bacteraemia, although consecutive samples were positive only on three occasions. Group 3 lambs consistently grew more rapidly than the surviving group 1 lambs and as rapidly as group 2 lambs. There was no evidence that male lambs were more prone to watery mouth disease than female lambs. The results indicated that the antibiotic spectinomycin did not induce endotoxaemia during low-grade bacteraemia and that a single oral dose given within two hours of birth protected colostrum-deprived lambs delivered into a contaminated indoor environment against watery mouth disease.  相似文献   

16.
Cortisol responses of Dorset and Scottish Blackface lambs were investigated at six ages between birth and seven days. There were four treatments: control handling and blood sampling (n = 52), tail docking (T) (n = 57), castration plus tail docking (CT) (n = 54), and intravenous adrenocorticotrophin (ACTH) injection (n = 60). Most lambs exhibited transient rises in plasma cortisol concentrations after treatment and the results in individuals were expressed as the area under the cortisol curve (integrated response). Postnatal changes in the integrated responses of control, T and CT lambs differed significantly between the two breeds; in Dorsets they increased markedly between four hours and one day and then decreased, whereas in Scottish Blackface lambs there were no significant changes. The cortisol responses of ACTH lambs decreased markedly between four hours and seven days in both breeds. The results shed light on postnatal changes in the activity of the hypothalamic-pituitary-adrenal axis and suggest for both breeds that the average increments in ACTH secretion caused by noxious stimuli increased markedly during the first one to three days after birth. Whether this reflected parallel increases in the levels of distress experienced by the lambs remains to be clarified.  相似文献   

17.
The roles of recipient and embryo genotype in determining the growth performance and survivability of offspring based on specific behavioural differences were investigated using inter‐breed embryo transfer. This study was carried out using three recipient genotypes (Awassi, Redkaraman and Tuj) and two embryo genotypes (Charollais and Romanov) to obtain the six possible combinations of ewe and lamb genotypes. Data were collected from 71 recipient ewes (10 Redkaraman with Charollais and 15 Redkaraman with Romanov embryos; 10 Tuj with Charollais and 12 Tuj with Romanov embryos, and 12 Awassi with Charollais lambs and 12 Awassi with Romanov embryos); all ewes received two frozen‐thawed embryos. Awassi ewes had a significantly longer duration of the licking/grooming event (25.5 min, p < 0.05) than Tuj ewes. Charollais lambs were significantly (p < 0.05) more likely to require birth assistance compared to Romanov lambs. Romanov lambs were significantly more (p < 0.01) active than Charollais lambs in the first 2 h after birth; ewe breed had no effect on lamb behaviour. There was no recipient breed effect on either birth or weaning weights of lambs. Charollais lambs were recorded with higher birth (5.5 ± 0.3 kg vs 3.9 ± 0.2 kg; p < 0.001) and weaning (29.4 ± 1.2 kg vs 22.4 ± 1.9 kg; p < 0.001) weights compared to Romanov lambs. At weaning Romanov lambs had significantly higher (95% vs 75%; p < 0.05) survival rates, however, this was not significantly affected by recipient breed. It was concluded that recipient breed was not an important factor in survival and weaning performance of embryo transferred lambs from a prolific breed (Romanov) while these traits recorded for lambs from meat type (Charollais) embryos were influenced by dam breed.  相似文献   

18.
This study aimed to evaluate sex, the number of lambs per birth, and the family effects on production traits in the Santa Ines breed of sheep by estimating the least square means and coefficient of variance for those traits. A total of 484 lambs were evaluated for the following traits: weight at birth, at weaning, and at 240 days of age; weight gain during the pre-weaning and post-weaning periods; height, width, and length of different body regions; and rib eye area and fat thickness between the 12th and 13th ribs. We observed coefficients of variation higher than 10 % for several traits. Generally, males were larger than females (P?P?P?ANOVA.  相似文献   

19.
本试验在干物质采食量一致条件下,改变精料补充料与饲草比例调控妊娠后期母羊饲粮营养水平,旨在研究其对产后羔羊生长性能、器官发育和血清抗氧化指标的影响.选用健康、年龄[(11.0±1.0)月龄]和体重[(44.43±2.20) kg]相近、妊娠90 d的怀双羔初产湖羊母羊66只,分为3组,每组22只.以干物质为基础按照精料补充料与饲草比例分别为5∶5(5∶5组)、4∶6(4∶6组)和3∶7(3∶7组)饲喂至产羔,产羔后各组母羊饲喂相同的全混合日粮,自由采食.出生10、60 d屠宰羔羊测定各组织器官重量,出生20、60 d采集羔羊血清测定血清抗氧化指标.结果表明:1)妊娠后期母羊饲粮营养水平对羔羊初生重、哺乳期(出生0～60 d)羔羊体重均无显著影响(P>0.05),但随营养水平降低,羔羊初生重有降低趋势(0.05≤P<0.10),出生40和50 d体重有增加趋势(0.05≤P<0.10).2)出生0d,随着妊娠后期母羊饲粮营养水平的降低,羔羊的胸深极显著提高(P<0.01),体斜长显著降低(P<0.05);出生60 d,随着妊娠后期母羊饲粮营养水平的降低,羔羊的胸深、曲冠臀长显著或极显著提高(P<0.05或P<0.01).3)出生10 d,羔羊的肝脏、肺脏的重量随妊娠后期母羊饲粮营养水平的降低而显著降低(P<0.05);出生60 d,各组羔羊的组织器官重量差异不显著(P>0.05).4)出生20和60 d,随着妊娠后期母羊饲粮营养水平的降低,羔羊血清中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化酶(GSH-Px)含量显著或极显著提高(P<0.05或P<0.01),丙二醛(MDA)含量极显著降低(P<0.01).妊娠后期通过精料补充料与饲草比例调控母羊饲粮营养水平时发现,低营养水平(低精料补充料比例)能够降低羔羊初生重,但经补偿生长作用,羔羊血清抗氧化能力得到提高,生长性能也得到恢复.  相似文献   

20.
The development of a naturally acquired coccidia infection in lambs in Otago is described using data derived from faecal oocyst counts and specific differentiation of the oocysts. Oocysts first appeared in faeces of lambs 19–37 days after birth. Oocyst production reached a mean peak of 250 000 oocysts per gram when lambs were 40–50 days old and slowly declined with increasing age of lambs. Coccidial infections did not appear to have any obvious effect on weight gain. The numerically most numerous species of coccidia were Eimeria ovina, E. crandallis, E. ninakohlyakimovae, E. parva and E. weybridgensis.  相似文献   

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