Isoenzymes of alkaline phosphatase in serum of lambs and ewes.

Electrophoresis in polyacrylamide gels was used to identify isoenzymes of serum alkaline phosphatase in sheep. Skeletal isoenzyme predominated in the serum of lambs and liver, skeletal and intestinal isoenzymes were found in the serum of adult ewes. In r ewes (R-r-i blood group system) intestinal isoenzyme activity was 67 per cent of total serum activity; in R ewes intestinal activity was only 36 per cent of total activity. Relative activities of the three isoenzymes differed greatly within individual ewes and between individual ewes during pregnancy and lactation.     

Effects of maternal undernutrition during early pregnancy on growth, muscle cellularity, fiber type and carcass composition in lambs

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.     

Field studies on enzootic abortion of ewes in south east Scotland

Statistical data were collected from 20 sheep flocks in which enzootic abortion of ewes (EAE) was diagnosed by examination of fetal material and maternal blood samples. The abortion rate in the 10,645 ewes in these flocks was 7.6 per cent. Thirteen of the flocks were fully vaccinated against EAE but the abortion rate in these was still in the order of 6.5 per cent. EAE was the major cause of the problem as ascertained from the laboratory examination of samples from a wide range of cases of abortion. There is therefore evidence that, in some flocks in south east Scotland, the efficacy of the vaccine against EAE is unsatisfactory. The reasons for this are discussed.     

Incidence of indurative lymphocytic mastitis in a flock of sheep infected with maedi-visna virus

Sheep in a flock in which 88 per cent of the ewes had antibodies to maedi-visna virus were clinically examined for udder induration during lactation and after drying off. On both occasions about half of the ewes had indurated udders. Histological examination revealed lymphocytic mastitis associated with maedi-visna virus infection, in the udders of six of 25 hoggs (24 per cent), 21 of 39 shearlings (53.8 per cent) and 42 of 67 ewes (62.7 per cent). Distinct lung lesions were found in 8 per cent of the hoggs, 12.5 per cent of the shearlings and 10 per cent of the ewes. The results of a clinical examination of dry udders were correlated with the histological findings.     

Abattoir survey of acquired reproductive abnormalities in ewes.

Abnormalities of the reproductive tract of female sheep were studied by examining 9970 reproductive tracts from cull ewes and 23,536 tracts from nulliparous sheep (prime lambs) over a period of 12 months in abattoirs in south-west England. Overall, 3.37 per cent of the tracts were pregnant (8.11 per cent of cull ewes, and 1.36 per cent of nulliparous sheep), with a peak incidence between September and December. A total of 655 ewes (6.57 per cent) and 459 nulliparous sheep (1.95 per cent) had acquired abnormalities of the reproductive tract. Within these totals, abnormalities of the ovaries accounted for 3.51 per cent (for the ewes) and 10.68 per cent (for the nulliparous sheep) of all the abnormalities, and abnormalities of the ovarian bursa and uterine tube accounted for 42.1 per cent (for the ewes) and 5.23 per cent (for the nulliparous sheep). In addition, uterine lesions (hydrometra and metritis) accounted for 9.92 per cent (for the ewes) and 13.51 per cent (for the nulliparous sheep); lesions of the cervix and vagina (total of 1.44 per cent) and Cysticercus tenuicollis cysts associated with the reproductive tract (total of 3.05 per cent) were less common. Among the ewes the most common ovarian lesions were ovulation tags, and follicular cysts were the most common in nulliparous animals. Lesions such as bursitis, parametritis and abscesses of the reproductive tract were much more common in cull ewes than in nulliparous sheep, probably having arisen from peripartum infections. Hydrosalpinx and hydrometra, in which the intraluminal fluid was clear, were present at relatively high incidence in nulliparous animals, but not in cull ewes. The proportion of tracts containing macerated fetal remnants (2.14 per cent of all abnormalities in cull ewes) was lower than expected. It was considered that the functional significance of many of the lesions, such as ovulation tags and C tenuicollis cysts, was likely to be low, although in some cases of the latter calcification of the cyst had occluded the uterine tubes. Other lesions, notably hydrosalpinx, bursitis and metritis were likely to have made the affected animals sterile. The acquired abnormalities were therefore more significant in terms of individual animal infertility than as a major cause of infertility in flocks.     

Frequency and cost of human intervention at lambing: an interbreed comparison

The frequency of human intervention during lambing was assessed for 708 lambs and 162 ewes in up to four deliveries. In total, 21.8 per cent of the lambs born alive required some assistance at birth and 9.4 per cent were delivered manually. Assistance was required less frequently by twin lambs and ewe lambs, and Scottish blackface lambs required assistance less frequently than Suffolk lambs. Approximately one-third of the ewes were assisted in at least one delivery and 10 per cent were assisted in all their deliveries; however, less than 20 per cent of ewes were assisted more than once. A quarter of the lambs needed some human intervention to suck successfully, and Suffolk lambs needed help more frequently. The lambs born to almost half the first-parity ewes needed help to suck, but at later deliveries the lambs born to less than a third of the ewes needed assistance. In blackface flocks the survival of 100 lambs required 4.6 hours of human intervention whereas in Suffolk flocks 28 hours were required.     

Some factors affecting pregnancy rate in ewes following laparoscopic artificial insemination

The fertility of 646 ewes and gimmers bred by laparoscopic artificial insemination (LAI) in the autumn of 2006 was investigated using a questionnaire and individual ewe breeding records kept for 13 commercial sheep flocks that used LAI routinely. Overall, the pregnancy rate was 66 per cent, but it was highest in ewes bred for the fourth time. Technical aspects of LAI influenced fertility: pregnancy rates were 70 per cent for ewes bred using frozen semen compared with 58 per cent when fresh semen was used (P≤0.01), and 74 per cent of ewes that travelled to an artificial insemination centre for mating conceived, compared with 62 per cent that remained on their own farm (P<0.01). Higher doses of equine chorionic gonadotrophin (>400 iu) used for oestrus synchronisation reduced pregnancy rates to only 49 per cent (P<0.001). However, the largest effect was associated with shepherds gathering, handling and treating breeding ewes four to six weeks before mating; pregnancy rates were 54 per cent among ewes where this was carried out, compared with 74 per cent for ewes not treated in this way (P<0.01).     

Increase in plasma cortisol concentrations in ewes fed oestrogenic subterranean clover

Pen-feeding oestrogenic clover to ewes increased their plasma cortisol concentration by the third day. This was not due to any change in the variation of cortisol concentration with time of day. Ovulation rate was not affected during the experiment as judged by the levels of plasma progesterone and laparoscopy. The plasma cortisol concentration of ewes also rose within three days of their being placed on oestrogenic clover pasture. During the next 21 days, their mean plasma cortisol was increased by 58 per cent. A previous history of clover disease did not affect this response.     

Action of proteinase inhibitors in rats. 3. Influence of leupeptin on the rate of protein synthesis and the intracellular protein degradation by use of a test system including constant infusion of labelled amino acids, estimation of 3-methyl-histidine excretion and a triple-labelling technique

Male Wistar rats (initial body weight 90 g) were fed ad libitum a whole-egg diet containing 10,5% crude protein. The animals of the experimental group received in each case of 1 mg leupeptin per 100 g of body weight in 12 hrs-intervals by i. p.-injection (3 days of treatment). Control animals got a leupeptin free solution. In addition, lysine dihydrochloride-alpha-15N was applied during the first three days of experiment to all animals and the nitrogen balance was determined. Urine from the N-Balance collection was analysed for 3-methyl-histidine excretion in order to calculate the degradation rate of myofibrillar proteins. On the fourth day the fractional rate of protein synthesis in several organs was estimated using the continuous infusion technique with 14C-leucine and 14C-lysine. The apparent biological half-lives of tissue protein were determined by a triple labelling technique, with (14C)-guanidino-L-arginine, L-5-3H-arginine and 15N-Lysine. The short-term treatment 3 days) with leupeptin did not affect the weight gain, the apparent digestibility of nitrogen and the N-balance. The fractional rate of protein synthesis was highest in the small intestine followed by the large intestine, liver and skeletal muscle and no influence of leupeptin treatment was observed. Furthermore no differences in the degradation rates of myofibrillar proteins between treated and untreated animals were found. The 3-methyl-histidine excretion via urine was 1.44 mg . kg-1 day-1 in both groups corresponding to a fractional rate of degradation of myofibrillar proteins of 2,5% per day. Apparent half-lives of tissue proteins in the small intestine, large intestine and liver, respectively, were shortest when estimated from the decay curves for the 14C-label and longest from the curves for the 15N-label. Leupeptin treatment resulted in prolonged apparent half-lives of the proteins in the large intestine and of the slowly turning over proteins in the liver. However, this effect seems to be caused rather by an increased reutilization of labelled amino acids than by a decreased protein degradation. Before continuing this kind of work the rate of uptake of injected leupeptine into tissues has to be investigated. Studies dealing with the in vivo action of proteinase inhibitors on protein metabolism have to include estimations of N-balance, protein synthesis rate, intracellular degradation rate of proteins as well as amino acid reutilization.     

Increased responsiveness to dietary lysine deficiency of pectoralis major muscle protein turnover in broilers selected on breast development

It has been previously established that growth and carcass qualities of chicks are modified by genotype and dietary amino acid supply. In this study, we evaluated the effects of lysine deficiency and genetic selection on muscle protein metabolism. Chicks originating from an experimental line selected for breast development (QL) and its control line (CL) were provided ad libitum access to isoenergetic diets containing 20% crude protein but differing in their lysine content (0.75 or 1.01%). Protein fractional synthesis rates (FSR) were measured in vivo in the pectoralis major and sartorius muscles of 3-wk-old chickens (flooding dose of [3H]phenylalanine). Fractional breakdown rates (FBR) were estimated as the difference between synthesis and deposition. Lysine deficiency reduced (P < 0.001) growth performance and muscle weights and increased (P < 0.05) muscle FSR, capacity for protein synthesis (muscle RNA:Protein, Cs) and FBR. Although QL birds grew faster and had heavier pectoralis major muscles than CL birds (P < 0.05), there was no line difference in sartorius weight (P = 0.15). No difference between the lines was observed in sartorius protein metabolism (P > 0.14). In the pectoralis major muscle, chicks of both lines receiving an adequate lysine intake also exhibited similar protein turnover rates. However, in chicks fed the lysine-deficient (0.75% lysine) diet, FSR and Cs were higher in QL than in CL chicks (P < 0.05), and FBR tended (P = 0.07) to be higher in QL chicks. This increased protein turnover in the QL birds on the lysine-deficient diet suggests that the responsiveness of muscle protein metabolism to amino acid supply is modified by genetic selection for breast development.     

A census of the prevalence of vaginal prolapse in sheep flocks in the Borders region of Scotland

A postal census of vaginal prolapse in sheep flocks in the Borders region of Scotland yielded 540 replies from 963 owners (56 per cent). There were 262,250 ewes in 976 flocks and 2573 vaginal prolapses were reported. Analysis of the data revealed that 390 (40 per cent) of the flocks had no vaginal prolapses and in 237 (24.3 per cent) the reported prevalence was between 0.1 per cent and 1.0 per cent. Only 63 (6.5 per cent) of flocks had a greater than 5 per cent prevalence of vaginal prolapses. The greatest number of prolapses occurred in an upland flock of greyface ewes mated with Suffolk tups with 50 cases among 700 ewes (7.1 per cent) and the highest prevalence was in an upland Scottish blackface flock of ewes bred with Suffolk tups with 15.2 per cent (35 cases among 230 ewes). There were marked breed differences; very few hill breeds were affected and most cases occurred in greyface ewes mated with Suffolk tups.     

Effects of maternal nutrition on the availability of energy in the body reserves of fetuses at term and in colostrum from Scottish Blackface ewes with twin lambs

Ewes carrying twin fetuses were maintained during late pregnancy on a uniformly high plane (n = 22), a uniformly low plane (LP) (n = 24) or a low plane increasing to a high plane (n = 14) of nutrition. Seven ewes at each nutritional level were killed at 142 days of gestation and the liver and muscle glycogen and body lipid concentrations of the fetuses were determined. The rest of the ewes lambed naturally at about 145 days and the colostrum yields were obtained by hand milking after oxytocin injections during the first 18 hours after birth. The lactose, lipid and protein concentrations of colostrum were determined. Undernutrition in the LP group did not apparently affect the body concentrations of available glycogen, reduced available body lipid by about 47 per cent and reduced the lactose, lipid and protein available in colostrum during the first 18 hours by about 50 per cent. Refeeding previously underfed ewes to a high plane during the last five to 10 days of pregnancy did not improve the available reserves of glycogen or lipid in the lambs but did increase the yields of colostral constituents by about 30 per cent. The relative contributions of body reserves and colostral constituents to the maintenance of high, medium and low metabolic rates in lambs from different groups was assessed. It was concluded that under normal field conditions refeeding undernourished ewes during the last weeks of pregnancy would improve only marginally the survival potential of the lambs and that most lambs would be compelled to draw on their body glycogen reserves in order to maintain heat production during the first 18 hours after birth, even when they consumed all the available colostrum.     

妊娠早期饲粮中添加N-氨甲酰谷氨酸对母羊早期胚胎存活及相关血液指标的影响

本试验旨在研究妊娠早期饲粮中添加N-氨甲酰谷氨酸（NCG）对母羊胚胎存活及相关血液指标的影响,并对其作用机制进行初步探讨。选择发情正常、健康状况良好的湖羊50只,随机分为2组（对照组和NCG试验组）,每组25只母羊,自配种当天开始给母羊分别饲喂基础饲粮（对照组）和基础饲粮+0.11%NCG（NCG组）,饲喂期38 d。测定妊娠第19和38天母羊血浆游离氨基酸、总一氧化氮合酶（TNOS）、内皮型一氧化氮合酶（eNOS）、诱导型一氧化氮合酶（iNOS）、一氧化氮（NO）、雌二醇、孕酮的浓度;38 d时每组各屠宰7只妊娠母羊,测定妊娠母羊的黄体数和活胎儿数等指标。结果显示,与对照组相比,妊娠第38天时,NCG组每只母羊总胎儿数增加了79.72%（P<0.05）,活胎儿数增加了79.72%（P<0.05）,胎儿形成指数增加了0.26（P<0.05）,胎水体积增加了72.89%（P<0.05）,活胎儿总重提高了71.13% （P<0.05）;NCG组妊娠第19天的甘氨酸、蛋氨酸、赖氨酸、精氨酸、NO、iNOS、eNOS和孕酮的浓度显著高于对照组（P<0.05）,NCG组妊娠第19天的瓜氨酸和脯氨酸极显著高于对照组（P<0.01）;NCG组妊娠第38天的精氨酸、脯氨酸和NO显著高于对照组（P<0.05）,NCG组妊娠第38天的iNOS和eNOS的浓度极显著高于对照组（P<0.01）。由此,妊娠早期饲粮中添加NCG提高了胚胎和胎儿的存活,增加了妊娠母羊第38天的总胎儿数和活胎儿数,改善了母羊的繁殖性能,其作用机制可能是NCG促进了母羊内源性精氨酸的合成,提高了母羊血浆精氨酸、NO和孕酮含量,改善了子宫内环境和营养供给,使之有利于胚胎着床和妊娠维持。     

Clinical, biochemical and pathological study of perinatal lambs in a commercial flock

The birth and fate of 818 lambs born to 571 ewes on a low-ground farm in the Scottish Borders with a history of substantial perinatal mortality were monitored with a range of physiological, biochemical and pathological measurements. In lambs which survived, the rectal temperature, birthweight and plasma concentrations of fructose, insulin, thyroxine and the third component of complement at birth, and the weight at four months of age, decreased with litter size. One hundred and thirty-seven lambs were stillborn or died within four days and seven others died later. The mothers of 77 per cent of these lambs had low condition scores, but the lamb deaths did not correlate significantly with the condition scores. From data relating to birthweight, temperature, packed cell volume and plasma composition it was deduced that placental insufficiency was involved in 24 per cent of these deaths; acute hypoxaemia at birth accounted for 35 per cent, inadequate thermogenesis for 12 per cent and starvation for 13 per cent. The remaining 16 per cent of dead lambs could not be assigned to any of these categories. Using only clinicopathological criteria, 37 per cent of the lamb deaths were attributed to antenatal influences which included immaturity, developmental anomalies, and degenerative or inflammatory changes. Thirty-three per cent of the deaths were due to post natal factors which included, in declining order of frequency, starvation, enteritis, misadventure, pneumonia, navel infections and septicaemia. No conclusions could be drawn from the pathological examinations alone in the remaining 30 per cent, although almost half of these had low rectal temperatures after birth, death being attributed to hypothermia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Factors affecting the hypocalcaemic response to protamine.

The hypocalcaemic response to protamine, as a measure of bone resorption rate, was studied in cattle and sheep. Three groups of calves were studied (1–3 days, 2–3 weeks and 4 months old). The oldest calves showed the greatest response, indicating a more rapid skeletal turnover in these animals, probably related to a higher growing rate. A group of cows was tested at 2 occasions, near parturition and 2–3 weeks after parturition. The decrease in plasma calcium was small near parturition, while a profound drop was obtained 2–3 weeks post partum, which supports earlier findings that bone resorption is more or less blocked in parturient cows. Young pregnant ewes showed the same degree of hypocalcaemia as adult pregnant ewes but the recovery was more rapid in the young animals. Young rams were given protamine before and after diethylstilboestrol treatment. No differences in calcium response were obtained. Varying plasma phosphate responses were obtained. A pronounced hyperphosphataemia was found in the adult pregnant ewes. Diethylstilboestrol caused hypermagnesaemia in the rams.     

Nutrient restriction differentially modulates the mammalian target of rapamycin signaling and the ubiquitin-proteasome system in skeletal muscle of cows and their fetuses

The mammalian target of rapamycin (mTOR) signaling controls nutrient-stimulated protein synthesis in skeletal muscle, whereas ubiquitin-proteasome systems control the degradation of myofibrillar proteins. The objective of this study was to elucidate the effect of nutrient restriction on the mTOR signaling and ubiquitin-proteasome system in the skeletal muscle of cows and their fetuses. Beginning 30 d after conception, 20 cows were fed either a control diet that provided 100% nutrient requirements or a nutrient-restricted diet at 68.1% of NE(m) and 86.7% of metabolizable protein requirement. Cows were slaughtered on 125 d of gestation, and the LM of both cows and fetuses was sampled for the measurement of mTOR, ribosomal protein S6, adenosine 5'-monophosphate-activated protein kinase (AMPK), and protein ubiquitylation. When comparing the muscle samples from nutrient-restricted and control cows and their fetuses, no difference was observed for the content of mTOR and ribosomal protein S6, but the phosphorylation of mTOR at Ser(2448) and ribosomal protein S6 at Ser(235/336) were greater (P < 0.05) in control muscle than in muscle from nutrient-restricted animals. Because the phosphorylation of mTOR and ribosomal protein S6 upregulates translation, these results showed that nutrient restriction inhibits protein synthesis in muscle. The activity of AMPK in the muscle of nutrient-restricted cows was significantly lower (P = 0.05) than that of control cows. The protein ubiquitylation, however, was greater (P < 0.05) in the muscle from nutrient-restricted cows, showing accelerated protein degradation. No difference in the protein ubiquitylation was detected for fetal muscle. Data suggested that the decreased protein synthesis and promoted protein degradation resulted in muscle atrophy of pregnant cows, but not in fetal muscle. Results of this study show that in response to nutrient restriction, protein degradation was differentially regulated between cow and fetal muscle. The atrophy of cow muscle during nutrient deficiency may involve the enhanced degradation of muscle proteins.     

Some effects of copper deficiency on leucocyte function in sheep and cattle

Peripheral blood leucocytes from copper-deficient (less than 8 mumol per litre plasma) and copper-sufficient (more than 8 mumol per litre) ewes and lambs were tested for their ability to ingest and kill Candida albicans in vitro. Killing capacity was significantly reduced in both copper-deficient ewes and lambs, although phagocytic capacity was apparently unimpaired. Similar results were obtained with copper-deficient calves, in which it was further shown that copper repletion restored candidacidal activity. Leucocyte and erythrocyte superoxide dismutase (LSOD and ESOD respectively) activities were both significantly decreased in hypocupraemic ewes and there was a linear relationship between their activities in the two cell types: LSOD activities were reduced by approximately 35 per cent and ESOD activities by 67 per cent. Cyanide inhibition tests indicated that the manganese-dependent form of the enzyme contributed little to the total activity of LSOD or ESOD. There was a tendency for leucocytes from copper-deficient ewes to release greater amounts of superoxide anion after stimulation with opsonised zymosan. Their viability was similar to that of leucocytes from control sheep and was unaffected for up to three hours after stimulation.     

Fructose utilization for nucleic acid synthesis in the fetal pig

Eight fetal pigs, in utero, were injected ip with 20 microCi/fetus [U14C]-fructose between d 55 and 65 pregnancy. The isotope was allowed to equilibrate between blood and tissues within injected fetuses for a period of 240 min. Fetal pigs were then sacrificed and nucleic acids were extracted from cold tissue homogenates of skeletal muscle and liver. Nuclide disintegrations per minute recovered in extracted DNA and RNA were used to calculate incorporation of labeled C from fructose. The recovery of labeled C per mmol of nucleic acids from skeletal muscle was greater (P less than .05) than that from liver. Relative incorporation of labeled C into skeletal muscle RNA (395.9 pmol/mmol) was greater (P less than .05) than for DNA (189.5 pmol/mmol). The same trend was observed for liver RNA (78.0 pmol/mmol) and DNA (55.6 pmol/mmol), but differences were nonsignificant. These data suggest that at least part of the high concentration of endogenous fructose measured in fetal pigs in utero is involved in synthesis of nucleic acids, thereby providing substrate for anabolic functions necessary for fetal growth and development.     

Relations between maternal and fetal plasma concentrations of placental lactogen and placental and fetal weights in well-fed ewes

The concentration of ovine placental lactogen (oPL) in maternal plasma varies with litter size and nutritional status, making it difficult to compare these concentrations across studies. In this study, 27 Dorset and Finn-Dorset crossbred ewes with litters of known size and gestational age were used to relate concentrations of oPL in maternal plasma to placental and fetal weights. Fetal oPL concentrations also were correlated to these variables in 12 chronically catheterized singleton fetuses. The concentration of oPL in maternal plasma increased with increasing placental weight across litter sizes ranging from 1 to 3 (r = .716). When expressed per gram of placenta, oPL was greater (P less than .05) in those ewes carrying multiple fetuses. There was no correlation between maternal and fetal oPL in time-matched samples or in average values between individuals for ewes carrying singleton pregnancies. Within the singleton group, placental weight and fetal weight were well correlated (r = .761), as were the concentration of fetal plasma oPL and fetal weight (r = .699). Placental weight plus fetal oPL could explain 81% of the variation seen in fetal weight. These results imply that maternal and fetal oPL release are controlled independently and that fetal oPL affects fetal growth by a mechanism not directly related to placental size.