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1.
Studies were conducted to examine the effects of the cyclicity and the presence of a dominant follicle (DF) in ovary on the recovery and in vitro growth of pre-antral follicles (PFs) in sheep and buffalo. Small pre-antral follicles (SPFs, 100–250 μm) and large pre-antral follicles (LPFs, 250–450 μm) were isolated from slaughterhouse ovaries in the breeding seasons by a mechanical and enzymatic method. The sheep and buffalo PFs were cultured in vitro for 6 and 15 days, respectively, and examined for their growth, survival and antrum formation rates and growth rates of oocytes in cultured pre-antral follicles. The follicles of the sheep and buffalo were recovered and cultured simultaneously within replicates. The recovery rates (number per ovary) of both SPFs and LPFs were significantly (p < 0.05) higher in cyclic ewes (SPFs: 22.0 ± 3.3 vs 12.1 ± 2.6 and LPFs: 16.0 ± 3.6 vs 9.2 ± 1.8) and buffaloes (SPFs: 9.2 ± 1.3 vs 4.1 ± 1.0 and LPFs: 10.3 ± 2.7 vs 5.4 ± 0.7) compared with those recovered from acyclic ones. Presence of a DF in ovary significantly (p < 0.05) reduced the recovery rates of LPFs in ewes (9.06 ± 2.7 vs 16.4 ± 3.8) but had no effect in buffalo. Cyclicity of animals or follicular dominance had no effects on in vitro growth, survival and antrum formation rates and growth rates of oocytes in cultured PFs of SPFs and LPFs in both sheep and buffalo. The in vitro growth, survival and antrum formation rates of LPFs and growth rates of oocytes in cultured LPFs were significantly (p < 0.05) higher than those observed in SPFs in both sheep and buffalo. The overall recovery and growth rates of the PFs were lower in buffaloes compared with ewes.  相似文献   

2.
To determine the absorption and metabolism of 17β-estradiol (E2) by the stomach and liver of the pig, crystalline E2 was placed in the stomach of prepubertal gilts. Blood samples were subsequently obtained from the hepatic portal and jugular veins and plasma was assayed for E2, estrone (E1), 17β-estradiol-glucuronide (E2G), estrone-glucuronide (E1G) and estrone-sulfate (E1S). Concentrations of E2, E1, E2G and E1S rose in the hepatic portal vein within five min and remained elevated for several hr. Concentration of E2 represented only 6% of the total estrogen detected in the hepatic portal vein during the sampling period, indicating that most of the E2 was converted or conjugated prior to entering the hepatic portal vein. The metabolism of E2 presumably occurred in the stomach mucosa because food had been withheld for 26 hr before infusion of E2. Concentrations of E2G, E1G and E1S, but not E2 and E1, rose in the jugular vein and remained elevated for several hr. The lack of a rise in E2 and E1 in the jugular vein indicates that the E2 and E1 from the hepatic portal vein were completely converted and/or removed by the liver. Most of E2 was converted to E1 and then to E1G. The infusion of bile containing normal estrogens from pregnant gilts into the duodenum of prepubertal gilts resulted in a peak of E1G and E2G in the hepatic portal and jugular veins within a few minutes. This was followed in about 180 min by a second sustained rise. The first peak was essentially abolished by extracting E1 and E2 from the bile before infusion. The second peak failed to occur in gilts given antibiotics orally to reduce gut bacteria before infusion of bile.  相似文献   

3.
深入研究了当归属及其相关7属,古当归属,高山芹属,柳叶芹属,独活属,欧当归属,山芹属及前胡属毛状体和果实结构。结果显示毛状体及果实结构(如:毛状体细胞,翅,油管,维管束,中果皮,内果皮,结合面及结晶)可以用于区分当归属及其相关类群。滇南当归及隆萼当归应从当归属移入独活属,其余当归属物种分为结合面宽及结合面窄两组,前者与前胡属较为相似,但与独活属差别较大,后者与古当归属,高山芹属,柳叶芹属,欧当归属有相似之处。支持分子系统学揭示的当归属不是个自然类群,当归属与前胡属共同位于当归分支,而独活属位于独活分支。山芹属果实结构与其他属不同,翅的中果皮无细胞,且伴生油管位于维管束内侧,为分子系统学显示此属与高山芹属,柳叶芹属,及欧当归属亲缘关系较远提供了形态学依据。  相似文献   

4.
Delmadinone acetate (DMA)? was tested by oral or parenteral administration to forty female and ten male dogs, and to twenty female and ten male cats for the control of heat and ovulation, and suppression of undesirable sexual and social behaviour. The indications, particulars of medication and the results obtained are shown in the table. The mode of action on the hypothalamus, pituitary and target organs is discussed. Over a thirty-six month trial period DMA proved to be a safe and efficacious drug for the control of sexual and related social functions in female and male pet animals. There were indications that even lower dosages than those employed may prove to be equally effective. Résumé. De l'acétate de delmadinone a été soumis à des tests, par administration buccale ou parentérale, sur quarante chiens femelles et dix chiens mâles et sur vingts chats femelles et dix chats mâles, pour le contrôle du rut et de l'ovulation et pour la suppression de comportement indésirable, sexuel et social. Les indications, les détails de médication et les résultats obtenus sont indiqués à la table. On discute du mode d'action sur Phypothalamus, l'hypophyse et les organes-cibles. Au cours d'une période d'essai de 36 mois, l'acétate de delmadinone s'est révelé une drogue éfficace, sans danger, pour le contrôle des fonctions sexuelles et sociales apparentées, chez les animaux familiers femelles et mâles. Il y avaient certaines indications, que même des doses plus faibles que celles utilisées peuvent se montrer également éffectives. Zusammenfassung. Delmadinonazetat (DMA) wurde durch orale oder parenterale Vera-breichung an vierzig weibliche und zehn männliche Hiade und an zwanzig weibliche und zehn männliche Katzen zur Kontrolle der Hitze und Ovulation, und Suppression von unerwünschtem sexuellem und sozialem Verhalten, gegeben. Die Indikationen, Eigenheiten von Medikation und die erlangten Ergebnisse sind in der Tabelle verzeichnet. Die Art der Wirkung auf den Hypo-thalamus, die Hypophyse und die Erfolgsorgane ist erört. Über eine 36 monatige Versuchsperiode, DMA bewies sich als ein sicheres und wirksames Medikament zur Kontrolle von sexuellen und verbundenen sozialen Funktionen in weiblichen und männlichen Haustieren. Es gab Anzeichen, dass selbst eine niedrigere Dosis als die angewand, sich ebenso wirksam erweisen mag.  相似文献   

5.
The study was conducted to assess the effects of seasonal variation in the quality and quantity of pasture and management of livestock exclosures (ngitili) on the grazing behavior of cattle and goats. The study was 2×2×2 factorial design with three independent variables: season (Dry or Rainy), ngitili management (Private or Communal) and animal species (Cattle or Goats). Focal and scan observation methods were used to record different behavioral activities. Vegetation attributes from the study areas were measured in two consecutive seasons. Most key forage species had significant higher crude protein (CP) content and in vitro organic matter digestibility (INVOMD) in rainy than in dry season (P<0.05), but Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF) did not vary significantly with season (P>0.05). ADF and NDF were significantly higher in species from communal ngitili than those from private ngitili (P<0.05). Above-ground herbaceous biomass and bulk density (BD) were significantly higher in the rainy season and in the private ngitili than in the dry season and in the communal ngitili respectively. Cattle and goats spent considerably more time grazing and browsing respectively in the rainy season than in the dry season (P<0.05). Cattle foraging activities did not vary significantly (P>0.05) with ngitili management, but goats found to spend considerably more time browsing in the communal ngitili and more time grazing in the private ngitili (P<0.05). Despite the merits of stocking cattle and goats together in the heterogeneous pasture, seasonal variation in forage resources requires investigation of other strategies such as use of multipurpose trees and treatment of crop residues to improve livestock production.  相似文献   

6.
Three experiments were conducted to study the influence of level and type of L-carnitine (LC) on performance and rumiasl and plasma metabolites of weanling calves and finishing lambs. Weanling calves (84) grazing dormant dallisgrass-bermudagrass forage were fed a 20% CP supplement to provide 0, 0.5, 1, or 2 g of ruminally unprotected (RUP) LC per calf daily in Exp. 1. There was a linear increase (P=0.01) and cubic response (P=0.03) to RUP LC in growth rate and quadratic changes (P=0.01) in plasma ammonia N (PAN) and plasma urea N (PUN). In Exp. 2, 32 lambs were individually fed 14% CP diets containing 0, 50, 100, or 200 ppm RUP LC or ruminally protected (RP) LC in a 2 × 4 arrangement of treatments. Lambs gained BW faster (P=0.03) and more efficiently (P=0.07) as the LC level increased to 100 ppm and then declined at 200 ppm (quadratic response). Longissimus area decreased (P=0.03), and fat cover tended (P=0.15) to decline, at 50 and 100 ppm LC and increased at 200 ppm (linear and quadratic response). Ruminal ammonia N levels were reduced at 50 ppm LC but increased at greater LC levels (linear, quadratic, and cubic response, P=0.02). Plasma carnitine concentrations increased (P=0.01) as the dietary level of LC increased. Protected LC was more effective than RUP LC in increasing growth rate (P=0.06) and reducing PAN (P=0.1). In Exp. 3, 16 wether and 16 ewe lambs were individually fed corn-based or soybean hull-based diets with 0 or 100 ppm RP LC in a 2 × 2 arrangement of treatments. Lambs fed RP LC gained BW faster and more efficiently (P=0.04) than lambs that were not fed LC. Lambs fed corn-based and soybean hull-based diets responded similarly to RP LC; however, performance was greater (P=0.03) for lambs fed the corn-based diet. Gender of lambs did not influence the response to diet or RP LC. Supplementing the diet with 100 ppm RP LC reduced (P=0.01) ruminal pH and ammonia N. Plasma carnitine concentrations were increased (P=0.01), and PAN was decreased (P=0.04) by feeding 100 ppm RP LC. Ruminnaly unprotected and RP LC were effective in improving growth rate in ruminants; the latter appeared to be more effective in finishing lambs. L-carnitine reduced ruminal ammonia N and plasma glucose and, in some cases, PAN and PUN.  相似文献   

7.
  1. By modifying the method of Duriér & Pernow (1956) the urinary excretion of free and conjugated histamine was examined in 11 healthy adult sheep.
  2. The mean excretion of free histamine was 9.8 ± 9.0 (s) µg base/24 hrs. (uncorrected for losses during extraction). When individual means were used, the range was: 2.1–34.2 µg base/24 hrs. The intraindividual variations were of the same order as the interindividual variations.
  3. The mean excretion of conjugated histamine was equivalent to 15.1 ± 9.9 (s) µg histamine base/24 hrs. In all animals the ratio conjugated/free histamine was above 1. The interindividual as well as the intraindividual variation for conjugated histamine was of the same order as for free histamine.
  相似文献   

8.
Abstract

AIMS: To compare the pharmacokinetics, distribution and efficacy (pharmacodynamic response) of intraruminal ivermectin (IVM) and moxidectin (MXD) administered at 0.2 and 0.4?mg/kg to naturally nematode-infected lambs, and to determine the ex vivo accumulation of these anthelmintics by Haemonchus contortus.

METHODS: Romney Marsh lambs, naturally infected with IVM-resistant H. contortus, were allocated to treatment groups based on faecal nematode egg counts. They received 0.2 or 0.4?mg/kg IVM or MXD (n=10 per group), or no treatment (Control; n=6), on Day 0. Samples from four animals from each treatment group, including abomasal parasites, were obtained on Day 1. Plasma samples were also collected from Day 0 to 14, and a faecal egg count reduction test (FECRT) and a controlled efficacy trial were carried out on Day 14. Concentrations of IVM and MXD in plasma, in abomasal and intestinal tissues and in H. contortus were evaluated by high-performance liquid chromatography. Additionally, the ex vivo drug accumulation of IVM and MXD by H. contortus was determined.

RESULTS: Peak plasma concentrations and the area under the concentration vs. time curve for both IVM and MXD were higher for 0.4 than 0.2?mg/kg treatments (p<0.05), but there were no differences for other parameters. Concentrations of IVM and MXD in the gastrointestinal target tissues and in H. contortus were higher compared to those measured in plasma. Concentrations of both drugs in H. contortus were correlated with those observed in the abomasal content (r=0.86; p<0.0001). The exposure of H. contortus to IVM and MXD was related to the administered dose. Mean FECRT and efficacy for removal of adult H. contortus was 0% for IVM at 0.2 and 0.4?mg/kg. For MXD, FECRT were >95% for both treatments, and efficacy against H. contortus was 85.1% and 98.1% for 0.2 and 0.4?mg/kg, respectively. The ex vivo accumulation of IVM and MXD in H. contortus was directly related to the drug concentration present in the environment and was influenced by the duration of exposure.

CONCLUSION: Administration of IVM and MXD at 0.4 compared with 0.2?mg/kg accounted for enhanced drug exposure in the target tissues, as well as higher drug concentrations within resistant nematodes. The current work is a further contribution to the evaluation of the relationship between drug efficacy and basic pharmacological issues in the presence of resistant parasite populations.  相似文献   

9.
Three experiments (Exp. 1, n = 144 broilers [Ross × Ross]; Exp. 2, n = 118 mallard ducklings [Anas platyrhynchos]; and Exp. 3, n = 75 mature mallard ducks) were conducted to determine the effects of 3 levels of unmilled hybrid rice on growth performance and organ and gastrointestinal tract development. The dietary treatments were 1) corn-soybean meal (basal), 2) basal + 5% hybrid rice, and 3) basal + 10% hybrid rice for Exp. 1 to 3, respectively. One bird from each pen in Exp. 1 (n = 24) and all the birds in Exp. 2 (n = 118) and Exp. 3 (n = 75) were randomly selected and euthanized to determine linear measurements and organ and gastrointestinal tract weight. In Exp. 1 and 2, birds fed 10% rice experienced slower growth (P < 0.05) than birds fed the basal diet. In Exp. 3, the addition of rice did not affect growth performance. Rice addition did not affect organ length or weight (P > 0.05) in Exp. 1. However, birds fed 5% rice had significantly increased (P < 0.05) pancreas, ileum, and jejunum weights in Exp. 2, and 10% rice significantly increased (P < 0.05) liver weight in Exp. 3. The addition of 10% unmilled rice to broiler and duck diets may reduce growth performance.  相似文献   

10.
The objectives of this study were to estimate the environmental and additive and non-additive genetic effects on lactation curve and lactation parameters of crosses of Holstein (H), Brahman (B) and Brown Swiss (BS) in Olancho region in Honduras. The data consisted of 54,517 milk yield records from 192 dual-purpose crossbred cows lactating from 2000 to 2005 at the Universidad Nacional de Agricultura de Honduras (UNA). The lactation curve and lactation parameters of interest were the scaling factor to represent yield at the beginning of lactation (a), the factor associated with the inclining (b) and declining (c) slopes of the lactation curves, and the milk yield at initial day of lactation (MY20), peak milk yield (MYmax), day at peak milk yield (tmax), and the total milk yield (TM) per lactation, respectively. The incomplete gamma function (Wood function) was used to estimate lactation curve and lactation parameters from daily milk records of H × B, H × BS and BS × B crossbred cows. The environmental, additive and non-additive genetic effects on lactation curve and lactation parameters were estimated using Dickerson and Kinghorn models. The coefficients of determination of fitness of Wood's function (R2) ranged from 80% to 97% with an average of 93%. The lactation curve of the crossbred cows was similar to those reported for dairy cows grazing in the tropics. Lactation parameters such as MYmax, tmax and TM were significantly (P < 0.05) influenced by environmental sources of variation suggesting the necessity of differential management strategies. The moderate to large positive phenotypic correlation of MYmax and TM indicate that one of the milk yield parameters could be used as a selection criterion to improve either one or both traits. Despite the fact that both genetic models showed similar patterns, the absolute value of the parameters varied. For both models, individual additive genetic breed effect for H breed were significant (P < 0.05) and contributed more to TM than the BS breed. In the Dickerson model, highly positive significant (P < 0.01) effect on TM for H×BS and BS×B crosses was found. The Kinghorn model did not show significant effects of dominance on this parameter. The estimate of recombination effect for all crosses involving B breed were negative and significant (P < 0.05) for positive correlated lactation curve parameters. Although the inclusion of non-additive effects on crossbreeding genetic effects were not all significant for lactation curve and lactation parameters, non-additive effects should be taken into account to improve the Honduran dairy cattle production management.  相似文献   

11.
Tickborne diseases (TBDs) such as Lyme disease (LD), babesiosis, ehrlichiosis and Rocky Mountain spotted fever cause substantial morbidity and even mortality in the USA. Data indicate that Hispanic populations may be at greater risk for occupational exposure to ticks and disseminated LD; however, information on knowledge and practices of Hispanic populations regarding TBDs is limited. We surveyed 153 Hispanic and 153 non‐Hispanic residents of Maryland and Virginia to assess awareness of TBDs, prevention practices and risk of tick encounters. Hispanic respondents were less likely than non‐Hispanics to report familiarity with LD symptoms (21% vs. 53%, p < 0.001) and correctly identify ticks as vectors of LD (40% vs. 85%, p < 0.001). Although there was no significant difference in overall proportion of respondents who routinely take one or more preventive measures to prevent tick bites (59% vs. 61%, p = 0.65), Hispanics were more likely to report showering after coming indoors (36% vs. 25%, p = 0.04) but less likely to conduct daily tick checks compared with non‐Hispanics (17% vs. 35%, p < 0.001). History of tick bite or finding a tick crawling on oneself or a household member in the past year did not significantly differ between Hispanics and non‐Hispanics (19% vs. 24%, p = 0.26). Notably, after controlling for Hispanic/non‐Hispanic ethnicity, primary language (English vs. Spanish) was a significant predictor of whether an individual had knowledge of LD symptoms, correctly identified ticks as vectors for LD and performed daily tick checks. These results provide guidance for future development of more targeted and effective TBD prevention education for both Hispanic and non‐Hispanic communities.  相似文献   

12.
We investigated the reproductive and lifetime performances of Kagoshima Berkshire gilts and sows. We examined 20 605 parity records of 4419 pigs for 2008 to 2012 on a farrow‐to‐finish commercial farm. The mean parity (± SD) of all animals was 3.0 ± 2.1. For farrowing performance, the highest numbers of total pigs born and pigs born alive were found in sows with parities 5 and 6 and with parity 3–6, respectively (P < 0.05). Regarding weaning and mating performance, sows with parity 2 had the lowest preweaning mortality (P < 0.05). The longest weaning‐to‐first‐mating interval was found in parity 1 pigs, and the interval decreased as parity increased (P < 0.05). Parities 0 and 1 pigs had the lowest farrowing rate and those with parity 4 had the highest farrowing rate (P < 0.05). The mean parity at culling, total number of pigs born alive in a lifetime, and nonproductive days in a lifetime were 5.5 ± 2.93, 49.2 ± 24.72 pigs, and 132.1 ± 83.34 days, respectively. These animals had a lower litter size and fertility that the F1 crossbred sows mainly used in Japan, but a similar tendency for performance by parity.  相似文献   

13.
The aim of this study was to evaluate the pharmacokinetics and bioavailability of cefquinome (CFQ) and ceftriaxone (CTX) following intravenous (IV) and intramuscular (IM) administrations in premature calves. Using a parallel design, 24 premature calves were randomly divided into the two antibiotic groups. Each of the six animals in the first group received CFQ (2 mg/kg) through IV or IM administration. The second group received CTX (20 mg/kg) via the same administration route. Plasma concentrations of the drugs were analyzed by high‐performance liquid chromatography and noncompartmental methods. Mean pharmacokinetic parameters of CFQ and CTX following IV administration were as follows: elimination half‐life (t1/2λz) 1.85 and 3.31 hr, area under the plasma concentration–time curve (AUC0–∞) 15.74 and 174 hr * μg/ml, volume of distribution at steady‐state 0.37 and 0.45 L/kg, and total body clearance 0.13 and 0.12 L hr?1 kg?1, respectively. Mean pharmacokinetic parameters of CFQ and CTX after IM injection were as follows: peak concentration 4.56 and 25.04 μg/ml, time to reach peak concentration 1 and 1.5 hr, t1/2λz 4.74 and 3.62 hr, and AUC0–∞ 22.75 and 147 hr * μg/ml, respectively. The bioavailability of CFQ and CTX after IM injection was 141% and 79%, respectively. IM administration of CFQ (2 mg/kg) and CTX (20 mg/kg) can be recommended at 12‐hr interval for treating infections caused by susceptible bacteria, with minimum inhibitory concentration values of ≤0.5 and ≤4 μg/ml, respectively, in premature calves. However, further research is indicated to assess the pharmacokinetic parameters following multiple doses of the drug in premature calves.  相似文献   

14.
The effect of long-term exclusion of fire and herbivory, as mediated by aspect, on soils and the structure, composition, and diversity of vegetation was investigated in Döhne Sourveld (34 years), Piet-Retief Sourveld (45 years) and Southern Tall Grassveld (49 years). Exclusion had no effect on the soil chemistry of the surface 15 cm of soil in Dohne and Piet Retief Sourveld. Exclusion promoted the ingress of woody elements, including heath-like species, but the extent of ingress was related to water availability (rainfall, aspect), proximity of propagules, duration of protection, and accidental fires. Alien invasive woody species, in particular Acacia mearnsii established at all sites. Woody species were mostly bird- or wind dispersed, some had no known nearby population, although some Acacia species were herbivore-dispersed. The wettest grassland, Piet Retief Sourveld on a southern aspect, was transformed to a shrubland matrix (mainly Helichrysum splendidum) with tree clumps of forest precursor species (Rhus dentata, Halleria lucida, Myrsine africana, Buddleja salviifolia, Leucosidea sericea) and A. mearnsii. A species-rich grassland on the northern aspect had become dominated by tall Hyparrhenia rufa, with scattered shrubs of L. sericea and Helichrysum rogulosum. The southern aspect exclosure in Döhne Sourveld had developed an A. mearnsii - B. salviifolia savanna, with Cymbopogon excavatus, Themeda triandra and Tristachya leucothrix as common grasses. The northern aspect exclosure on Döhne Sourveld maintained a grassland character, although heath-like elements (Stoebe vulgaris, Erica aspalanthifolia) established. Protection of the Southern Tall Grassveld promoted an open savanna of exotic and indigenous Acacia and broadleaf species, an increase in life forms including the succulent Aloe maculata, and the transformation of a T. triandra - T. leucothrix sward to an Aristida junciformis sward. Ferns benefitted from exclusion of fire and herbivory. Fire and herbivory rather than soil properties would seem the primary determinants of the structure of sour grasslands.  相似文献   

15.
Five days after the induction of acute systemic inflammation in greyhounds by intramuscular and subcutaneous injections of Freund's adjuvant, the hepatic concentrations of cytochromes P-450 and b5, the activities of the hepatic microsomal enzymes aniline p-hydroxylase and aminopyrine n-demethylase and the disposition and urinary excretion of phenylbutazone were determined. The mean plasma concentrations of phenylbutazone after intravenous administration were described by the bi-exponential equations: Cp = 144·2e−34·6t + 171·5e−0·104t for five normal greyhounds and Cp = 113·6e−16·13t + 163·1e−0·108t for five febrile greyhounds. The elimination half-lives, total body clearances and apparent volumes of distribution were 6·7 hours, 18·4 ml kg−1 hour−1 and 0·18 litre kg−1, for the normal greyhounds, and 6·4 hours, 19·5 ml kg−1 hour−1 and 0·18 litre kg−1, for the febrile greyhounds. There were no significant differences between the pharmacokinetic parameters describing the distribution and elimination of phenylbutazone, or between the quantities of phenylbutazone, oxyphenbutazone and hydroxyphenylbutazone excreted in the urine. In the febrile greyhounds, there were significant decreases in the hepatic microsomal concentrations of cytochromes P-450 and b5 and in the activities of aniline p-hydroxylase and aminopyrine n-demethylase.  相似文献   

16.
Forty-four Thoroughbred and Quarter Horse weanlings were used in three experiments to evaluate the effects of energy content, protein content, and feeding levels of the concentrate on growth and development when fed with Coastal bermudagrass hay. The animals were confined to drylot paddocks and fed the assigned concentrate in individual feeding stalls. The hay was group-fed in the paddocks. In the first experiment, the concentrate was fed at 1.5 kg/100 kg BW daily or ad libitum for two 1.5-h feeding periods daily. The ad libitum-fed weanlings had greater withers height gain (P<0.01), and hip height gain (P<0.05) than the limit-fed weanlings. Bone mineral gains were numerically greater for the ad libitum-fed weanlings (P>0.10). None of the other body measurements were different (P>0.05). In Exp. 2, weanlings were fed a basal concentrate ad libitum for two1.5-h feeding periods daily or a fat-added concentrate at equal amounts to the hay intake. Nutrients were balanced to meet NRC recommendations. The fat-added concentrate resulted in numerically greater withers height (P>0.10), heart girth (P>0.10), body length (P>0.10), hip height (P>0.10), and bone mineral (P>0.10) gains. Weight gain and feed efficiency favored the basal diet. In Exp. 3, weanlings were fed concentrates providing either 14 or 18% CP as described previously. The BW gains favored the high protein diets for three of the first four periods (P<0.05), and some numerical advantage persisted to the end of the trial (P>0.10). None of the other growth measurements were different for the two diets. Calculations on nutrient intake and BW gains of the animals on the three experiments revealed that lysine intake appears to be a greater factor than energy or protein in influencing BW gain of weanlings.  相似文献   

17.

Objective

To evaluate and compare the analgesic efficacy and adverse effects of dexketoprofen and methadone using a noninferiority trial, during the first 24 postoperative hours in dogs undergoing orthopaedic surgery.

Study design

Randomized, blinded clinical study.

Animals

A total of 38 healthy dogs undergoing orthopaedic surgery.

Methods

Dogs were premedicated with dexmedetomidine [1 μg kg–1 intravenously (IV)] followed by dexketoprofen (1 mg kg–1 IV; group DK) or methadone (0.2 mg kg–1 IV; group M). Anaesthesia was induced with propofol and maintained with isoflurane in 60% oxygen. Postoperatively, dexketoprofen was administered every 8 hours (group DK) and methadone every 4 hours (group M). Analgesia was assessed at baseline and at 1, 2, 4, 6, 18 and 24 hours after extubation using a dynamic and interactive visual analogue scale (DIVAS), the short form of the Glasgow Composite Measure Pain Scale (CMPS-SF), mechanical wound thresholds (MWTs) and plasma cortisol levels. If CMPS-SF score was ≥5, rescue analgesia was administered. Data were analysed using a general linear mixed model, Mann–Whitney U test and chi-squared test as appropriate; a p value <0.05 was considered significant.

Results

The CMPS-SF and DIVAS scores were significantly higher in group M compared with group DK and remained higher for a longer period in group M, although the differences were not clinically significant. No significant differences were found in MWT assessment between groups. Plasma cortisol level significantly increased 2 hours after extubation, without significant differences between treatments. Rescue analgesia was administered to three animals (one in group DK; two in group M).

Conclusion and clinical relevance

We conclude that 1 mg kg–1 IV dexketoprofen administered every 8 hours during the first 24 hours postoperatively is noninferior to methadone in controlling pain after orthopaedic surgery in dog, although frequent pain assessments are recommended to adjust the analgesia plan.  相似文献   

18.
Redberry juniper (Juniperus pinchotii Sudworth) is an invasive, evergreen tree that is rapidly expanding throughout western and central Texas. Goats will consume some juniper on rangelands; however, intake is limited. The objective of our research was to determine how the age and body condition of goats influence their consumption of juniper and an artificial feed containing 4 monoterpenes. Two separate experiments were conducted. Experiment 1 examined the intake of redberry juniper foliage and used 39 goats either young (2 yr) or mature (> 6 yr). One-half of each age group was fed appropriate basal rations to reach either a high (HBC) or low body condition (LBC). Goats in LBC ate more (P < 0.01, 8.6 g · kg−1 body weight [BW] ± 0.7 SE) juniper than those in HBC (2.3 g · kg−1 BW ± 0.3 SE), and young animals consumed more (P < 0.05, 7.2 g · kg−1 BW ± 0.7 SE) juniper than mature goats (3.9 g · kg−1 BW ± 0.5 SE) across body condition treatments. In experiment 2, 36 goats, either young (2 yr) or mature (> 6 yr) and in either HBC or LBC, were offered a synthetic ration treated with 20.8 g · kg−1 of 4 monoterpenes found in redberry juniper. Goats in LBC ate more (P < 0.01, 25.3 g · kg−1 BW ± 1.0 SE) of the terpene-treated feed than those in HBC (17.5 g · kg−1 BW ± 0.7 SE), and young animals ate more (P < 0.05, 22.5 g · kg−1 BW ± 0.8 SE) than mature goats (20.3 g · kg−1 BW ± 0.8 SE) across body condition treatments. Total intake as a proportion of body weight was also affected by body condition. Age and body condition are important factors that influence intake of chemically defended plants. A better understanding of how these attributes affect diet selection will aid livestock producers in improving grazing management.  相似文献   

19.
The pharmacokinetics of carbetocin, which is used to control postpartum hemorrhage after giving birth, was studied in cows and gilts after a single intravenous (IV) or intramuscular (IM) injection. Blood samples from animals were assessed by oxytocin radioimmunoassay, and then the pharmacokinetic parameters were calculated using a noncompartmental model. For gilts, there was no significant difference between half-life (T1/2λZ), mean residue time (MRT), and maximum concentration (Cmax) between IM and IV administration. Conversely, the time to reach the Cmax (Tmax) and MRT were higher following administration of 350 μg/animal in cows via the IM administration compared with IV. The longest T1/2λZ was 0.85 hr, indicating carbetocin was absorbed and eliminated rapidly in both animal species after administration. The Tmax was similar between cows and gilts following IM administration. Moreover, the Cmax after IM injection was about half that of IV administration in both animals. The bioavailability was more than 80% in cows, suggesting administration via the IM route is efficient. This is in agreement with the longer T1/2λZ in cows after IM administration. However, the IV route is recommended for gilts due to a lower bioavailability (35%) and shorter T1/2λZ after IM administration compared with IV.  相似文献   

20.
Crossbreeding is an effective method of improving the efficiency and profit of production in commercial pig operations. To understand the effect of crossbreeding on meat and nutrient quality, a combination including three purebred (Duroc, D; Landrace, L; Yorkshire, Y) and two crossbred pig lines (Landrace × Yorkshire, LY; Duroc × (Landrace × Yorkshire), DLY) frequently used internationally were studied. The results showed that meat from the LY and DLY crosses had lower values for lightness , shear force and epinephrine and higher values for drip loss, C18:1, insulin, glucagon and monounsaturated fatty acids than D, L and Y pigs. Moreover, LY had higher values for post mortem pH and lower values for a* and b* than the purebreds. In contrast, DLY had lower values for pH and higher values for a* and b* than the purebreds. Meat quality‐related gene analysis showed that the CAST, IGF2 and MC4R gene expression levels in the LY and DLY pigs were significantly higher than those in the D, L and Y pigs. These results indicate that crossbreeding can alter the meat quality, nutritive value, energy metabolism and gene expression of pigs. Future research should focus on microRNA expression and DNA methylation that regulate gene expression and thus affect the meat quality.  相似文献   

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