Serum growth hormone and insulin-like growth factor-1 concentrations in Japanese black cattle with growth retardation

Serum concentrations of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) were determined in 5 calves in the same lineage with growth retardation. They had normal appetites, activities, body proportion, and laboratory test results. Calves with growth retardation had higher serum GH concentrations and lower serum IGF-I concentrations. These findings suggested defects in the GH-IGF-1 axis, such as in the GH-receptor.     

Rate, composition and efficiency of growth in feedlot steers reimplanted with growth stimulants

Eighty Charolais-cross steer calves (283 kg) were fed a moderately high-energy (2.89 Mcal ME/kg) diet for 189 d to examine the effects of reimplantation of 36 mg of zeranol (Ralgro) or 200 mg progesterone plus 20 mg estradiol benzoate (Synovex-S) on the rate, composition and efficiency of gain, skeletal size and carcass parameters in a comparative slaughter trial. The implant treatments included unimplanted controls (C), Ralgro initially (R1), Synovex-S initially (S1), Ralgro initially and a reimplant at 84 d (R2) and Synovex-S initially and a reimplant at 84 d (S2). Both implants increased (P less than .06) gains by 8.1% from 0 to 84 d. Ralgro and Synovex-S increased (P less than .01) daily gains by 11.5% and 25.2%, respectively, from 84 to 189 d. The duration of the response to a single implant appeared to be in excess of 140 d; thus, reimplantation did not further increase daily gains. Reimplantation did improve (P less than .05) feed utilization in Ralgro implanted steers, however. Ralgro and Synovex-S increased (P less than .01) the rate of empty body (EB) protein accretion by 14.1% and 24%, respectively, without affecting EB fat growth. The efficiency of protein gain per unit protein (P less than .05) or energy intake (P less than .04) was improved, but the efficiency of energy gain per unit energy intake was not affected by implantation. Carcass weights of implanted steers were 5% greater (P less than .04) when adjusted to an equal carcass fatness. Both growth stimulants increased hip height (P less than .02), wither height (P less than .08) and body length (P less than .08) over C steers at slaughter.     

Measurements of growth hormone and insulin-like growth factor 1 in cats with diabetes mellitus

Serum concentrations of insulin-like growth factor 1 (IGF-1) and growth hormone were measured in 25 cats with untreated diabetes mellitus (11 of which were used for follow-up measurements, one to three, four to eight, nine to 12 and 13 to 16 weeks after their treatment with insulin began), 14 diabetic cats that had previously been treated with insulin, and seven diabetic cats that also had hypersomatotropism, two of which had not previously been treated with insulin; 18 healthy cats were used as controls. In the untreated diabetic cats the concentration of IGF-1 ranged from 13.0 to 433.0 ng/ml (median 170.5 ng/ml), which was significantly lower than the concentrations in the control cats (196.0 to 791.0 ng/ml, median 452.0 ng/ml). Their IGF-1 concentrations increased significantly when they were treated with insulin and after four to eight weeks were not different from those in the control cats. In the diabetic cats that had previously been treated with insulin the IGF-1 concentrations were 33.0 to 476.0 ng/ml (median 316.0 ng/ml), which was significantly lower than the concentrations in the control cats, but significantly higher than in the untreated diabetic cats. The IGF-1 concentrations in the two previously untreated diabetic cats with hypersomatotropism were low and low-normal but increased markedly after treatment with insulin. In the five previously treated cats with hypersomatotropism the concentration of IGF-1 was above the normal range. The concentrations of growth hormone in the treated and untreated diabetic cats without hypersomatotropisms were not significantly different and there was an overlap in its concentrations in the diabetic cats with and without hypersomatotropism.     

铜促生长与动物生长轴激素调控的关系

日粮中添加适量的铜可促进动物的生长，其作用机制可能是多方面的。已有研究表明，铜促生长与动物生长轴的激素调控密切相关，其机理可能是铜能调控促生长调节肽的合成和释放。     

Stunted growth and mortality associated with sodium deficiency

We investigated reports of stunted growth and high mortality occurring among young poultry in 38 small privately owned flocks in Vermont and New Hampshire. Tests for infectious agents including avian influenza and Newcastle disease viruses were negative, as were toxicologic tests for mycotoxins, heavy metals, pesticides, and monensin in feed samples. Analysis of 6 samples of implicated feed revealed 330-870 ppm of sodium (median level 350 ppm), whereas the recommended minimum level for chick feed is 1200-2000 ppm. A case-control study included 38 affected and 23 unaffected flocks. Statistical analysis showed that affected flocks were 29 times more likely to have consumed a particular brand of poultry feed (odds ratio = 29.2, 95% confidence interval = 3.2-675.8) but did not show any association between clinical signs and hatchery, location of chick purchase, chick purchase date, or years of producer experience.     

灌溉条件下不同生长年限紫花苜蓿生长及生产能力的研究

2007年4-10月在地处西辽河平原的内蒙古民族大学实验农场,对5个不同生长年限紫花苜蓿Medicago sativa生产能力进行了研究,结果表明:紫花苜蓿净光合速率总体上表现为生长2年较高、生长6年较低,但刈割茬次间有所不同。紫花苜蓿叶绿素a、叶绿素b的含量在第1茬中表现为随生长年限的增加而降低,而在第2、第3、第4茬中均以生长3年、生长4年含量较高,生长2年、生长6年含量较低。类胡萝卜素的含量在第1茬中随生长年限的增加而降低,其余各茬含量与生长年限的规律不明显。紫花苜蓿全年草产量生长2年生长3年生长4年生长6年生长1年。不同生长年限紫花苜蓿植株密度随生长年限的增加而降低,根腐率、根颈粗、颈蘖数均随生长年限的增加而增加。0～50cm土层内紫花苜蓿主根干质量和侧根数均以生长3年最高,而侧根干质量则以生长4年最大。     

Association of single nucleotide polymorphisms in the growth hormone and growth hormone receptor genes with blood serum insulin-like growth factor I concentration and growth traits in Angus cattle

This study was conducted to identify polymorphisms in the promoter and coding regions of the bovine growth hormone and growth hormone receptor genes and to study association of polymorphisms identified in these genes with growth traits and serum insulin-like growth factor-I (IGF-I) concentration. The denaturing gradient gel electrophoresis method and sequencing were utilized to identify three new single nucleotide polymorphisms in the promoter region of the growth hormone gene in Angus cattle. Polymerase chain reaction-based restriction fragment length polymorphism procedures were developed for rapid determination of the single nucleotide polymorphism genotypes in the growth hormone and the growth hormone receptor genes among Angus calves from lines divergently selected for high or low blood serum IGF-I concentration. The IGF-I concentration and growth traits were analyzed using animal models. The single nucleotide polymorphism in the promoter region of the growth hormone receptor gene was associated with serum IGF-I concentration on d 42 of the postweaning test and with mean IGF-I concentration. The associated effects of the markers need to be verified in other populations.     

Serum growth hormone and insulin-like growth factor-1 concentrations in Japanese black cattle with renal tubular dysplasia

To elucidate the cause of growth retardation, 14 cattle with renal tubular dysplasia (RTD) were investigated by determining serum growth hormone (GH) and insulin-like growth factor (IGF)-1 concentrations. Compared with 6 healthy cattle, the baseline, maximum, area under the curve and peak amplitude of serum GH concentrations were higher or tended to be higher. Serum IGF-1 concentrations were lower normal or lower in cattle with RTD than in healthy cattle. Serum IGF-1 concentrations correlated significantly with body weight and chest girth, but not with serum GH and creatinine concentrations. Growth retardation in RTD might be associated partially with GH resistance.     

日粮添加姜黄素对宫内发育迟缓断奶仔猪生长性能和肠道组织形态的影响

为了解姜黄素对宫内发育迟缓(intrauterine growth retardation,IUGR)断奶仔猪肠道组织形态和生长发育的影响,选取16头正常初生体重(normal birth weight, NBW)仔猪和16头IUGR仔猪,公母各半;26日龄断奶,分别饲喂基础日粮或姜黄素日粮(基础日粮+400 mg/kg姜黄素),即N(NBW+基础日粮)、NC(NBW+姜黄素日粮)、I(IUGR+基础日粮)和IC(IUGR+姜黄素日粮),每组8头,饲养至50日龄屠宰取样。结果显示:日粮添加姜黄素可以显著降低肠道隐窝深度(CD)(P0.05),显著升高肠道长度以及十二指肠绒毛高度(VH)和绒毛高度/隐窝深度比值(VCR)、空肠回肠VH和VCR的值(P0.05),显著提高干物质、粗蛋白、脂肪和总能量的表观消化率(P0.05);日粮添加姜黄素还可以提高肠道二糖酶活性、回肠黏膜胰岛素样生长因子(IGF-1)的含量以及IGF-1 mRNA表达量,增加肠道绒毛、微绒毛长度。提示:姜黄素可以改善IUGR断奶仔猪的肠道组织形态和消化吸收功能,促进生长发育。     

The influence of level of feeding on growth and serum insulin-like growth factor I and insulin-like growth factor-binding proteins in growing beef cattle supplemented with somatotropin

The objective of this study was to determine the effects of level of feeding on growth, feed efficiency (gain:feed; G:F), body composition (BC), and serum concentrations of somatotropin (ST), IGF-I, and IGF-binding proteins (BP) in growing beef cattle supplemented with bovine (b) ST. In each of two consecutive years, 40 growing beef cattle were blocked by weight (average BW: yr 1 = 316 kg, yr 2 = 305 kg) and used in a 2 x 2 factorial arrangement with main effects of bST (0 or 33 microg x kg BW(-1) x d(-1)) and level of feed intake (ad libitum [AL] or 0.75 AL). Relative to uninjected cattle, treatment with bST increased ADG 9.6% (1.14 vs 1.25 kg/d; P < 0.05) and increased G:F 8.1% (12.3 vs 13.3 gain [g]:feed [kg]; P < 0.05), whereas ADG in AL animals was 39% greater than that in 0.75 AL animals (1.39 vs 1.00 kg/d; P < 0.05). There was a tendency (P = 0.10) for a bST x level of feeding interaction, such that the increase in ADG with bST was greater in AL cattle than in 0.75 AL cattle (10.6 vs 7.8%; P = 0.10). Serum concentrations of ST were greater in 0.75 AL cattle than in AL cattle (13.0 vs 8.6 ng/mL; P < 0.05) and in bST-treated cattle than in uninjected cattle (16.3 vs 5.2 ng/mL; P < 0.05). Due to a bST x level of feeding interaction (P < 0.01), the magnitude of the increase in serum ST to exogenous bST was greater (P < 0.01) in 0.75 AL cattle than in AL cattle. Relative to uninjected cattle, treatment with bST increased (P < 0.05) serum concentrations of IGF-I and IGFBP-3 and reduced (P < 0.05) concentrations of IGFBP-2. Similarly, AL cattle had greater (P < 0.05) serum concentrations of IGF-I and IGFBP-3 and reduced (P < 0.05) IGFBP-2 compared with 0.75 AL cattle. In summary, treatment with bST increased growth rate and G:F and stimulated serum IGF-I and IGFBP-3 while reducing IGFBP-2. Feeding at 0.75 ad libitum intake reduced the magnitude of response for each of these variables. Thus, limit-feeding may reduce the effect of exogenous bST on growth rate by blunting bST-induced increases in IGF-I and IGFBP-3 and bST-induced decreases in IGFBP-2.     

紫花苜蓿生产力动态研究

2002--2005年进行紫花苜蓿生产力动态研究,发现紫花苜蓿种植不宜沿用传统轮作周期。结果表明,农田灌溉条件下草产量高峰出现在播种后的第2年,株丛密度和1级分枝数大幅下降是草产量下降的主要原因;以初花期作为刈割期,历年各茬平均草产量及其日均增长量均以第2茬最高;随生长年限的增加,紫花苜蓿返青期后延,根颈、根重和根体积增幅逐年减小。试验结果证明,农田灌溉条件下,特别是在较大的刈割强度下,粮草轮作中紫花苜蓿的种植年限不宜太长,应以3—5年为宜。     

Association of a genetic marker with blood serum insulin-like growth factor-I concentration and growth traits in Angus cattle

The objective of this research was to evaluate a biallelic genetic marker identified in the first promoter region of the bovine IGF-I gene. The point mutation was identified as a T-to-C transition by sequencing the polymorphic fragments. A PCR-RFLP procedure was developed for determining the marker genotypes. Marker genotypes were determined for 760 Angus calves from divergent lines that were created by selection for high or low serum IGF-I concentration (allele A: 63.9%, B: 36.1%). Data were analyzed using the multiple-trait derivative-free restricted maximum likelihood computer programs with animal models. The full animal model included fixed effects of marker genotype, birth year, season of birth, sex, age of dam, and selection line; random effects of animal, maternal genetic, and maternal permanent environmental effects; and a covariate for age of calf. Traits analyzed included blood serum IGF-I concentrations on d 28, 42, and 56 of the postweaning test, mean IGF-I concentration, birth weight, weaning weight, on-test weight, off-test weight, off-test hip height, postweaning gain, and weight gain during the 20-d period immediately after weaning. Results from the analysis across selection lines showed a significant association of the BB genotype with higher weight gain during the first 20 d after weaning and a slight dominance effect of the marker on postweaning gain. Analysis within the low IGF-I line also showed a significant association of the BB genotype with higher weight gain during the first 20 d after weaning and with on-test weight, although analysis within the high IGF-I line did not show any significant association. The associated effects of the marker need to be verified in other cattle populations.     

Equine oocyte maturation with epidermal growth factor

Epidermal growth factor (EGF) has been shown to have a positive effect during oocyte in vitro maturation in several species. This study was performed to establish the capacity of equine oocytes to undergo nuclear maturation in the presence of EGF and to localise its receptor in the equine ovary by immunohistochemical methods. Oocytes were obtained by aspiration and subsequent scraping from equine follicles (15-25 mm diameter) and cultured in 3 different treatment groups for 36 h: control Group (modified TCM 199 with 0.003% BSA), EGF Group (TCM-199 supplemented with 50 ng/ml EGF) and EMS Group (TCM 199 supplemented with 10% v/v oestrous mare serum). Each group was divided further into 3 treatments with tyrphostin A-47, a specific tyrosine kinase inhibitor, at 0, 10(-4) and 10(-6) mmol/l. Maturation was determined as the percentage of oocytes reaching metaphase II stage at the end of the culture period. Immunohistochemical detection of EGF-receptor (EGFR) was performed using a streptoavidin-biotin method. The recovery rate and oocyte retrieval were 84.6% (recovered oocytes/follicles aspirated) and 6.55 (oocytes/mare), respectively. Treatment with EGF significantly (P<0.05) increased the incidence of metaphase II stage compared with the control group (69.4 vs. 26.9% in controls, respectively). The specific-tyrosine kinase inhibitor A-47 was effective in suppressing EGF-effect on EGF-cultured oocytes; no significant differences were observed in EMS-supplemented oocytes when cultured with A-47. EGF-receptor was localised in follicles, with localisation being more prominent in the cumulus than in mural granulosa cells. This finding, together with the increase of oocyte nuclear maturation rate when using EGF in culture media and the inhibition of maturation by tyrphostin A-47, suggests a physiological role for EGF in the regulation of equine oocyte maturation. The results should help successful development of assisted reproductive technology in the horse.     

Response to a growth hormone-releasing hormone analog in heifers treated with recombinant growth hormone

Sixteen pregnant Holstein heifers (430kg) were used to determine the effect of long-term administration of a bovine growth hormone (bGH) made by recombinant DNA technology on the ability of a bolus injection of a growth hormone-releasing hormone analog (Ac-His-1, D-Ala-2, Nle-27, GHRH(1-29 NH2) to increase serum GH. Eight heifers received a daily intramuscular injection of bGH (50 mg/day) for 5 months while the other half received a daily injection of physiological saline (control) over the same period. On the last day of bGH treatment and 1, 5, 10 and 25 days after the cessation of bGH treatment, five heifers from each group were challenged with GHRH analog and the response to this releasing hormone analog was measured. Basal GH concentrations were elevated on the last day of treatment in bGH-treated heifers and declined to concentrations similar to control heifers by 1 day after cessation of treatment. Response to GHRH analog was impaired by bGH during the last day of treatment and one day later. Responsiveness returned to a level similar to controls by 5 days after the end of bGH treatment. Response to GHRH analog was lessened during the period of bGH treatment but there were no long term effects on the animals' ability to respond to the releasing hormone.     

Hormonal abnormalities in Pomeranians with normal coat and in Pomeranians with growth hormone-responsive dermatosis

Clinical status, skin biopsy specimens, and endocrine function were evaluated in normal-coated Pomeranians (n = 12) and Pomeranians affected with growth hormone (GH)-responsive dermatosis (n = 7), then were compared with values in mixed-breed dog controls (n = 19). All Pomeranians were clinically normal; however, the Pomeranians with GH-responsive dermatosis had bilateral alopecia and hyperpigmentation of the trunk, caudal portion of the thighs, and ventral neck region. Skin biopsy specimens from the affected Pomeranians had decreased-to-normal epidermal thickness and follicular atrophy, compared with normal-coated Pomeranians. Numerous elastin fibers were observed in the skin biopsy specimens of unaffected and affected Pomeranians. Both groups of Pomeranians had normal results of thyrotropin-releasing hormone (TRH) and thyrotropin (TSH) response, adrenocorticotropin (ACTH) stimulation, and dexamethasone suppression testing. There was no significant increase in serum GH concentration in either group of Pomeranians after xylazine or human GH-releasing factor (GHRF) administration, whereas control dogs had significant (P less than or equal to 0.05) increase in serum GH concentration after administration of either agent. Baseline plasma ACTH concentration in unaffected and affected Pomeranians was increased above the normal range (40 to 90 pg/ml). Post-ACTH administration serum progesterone, 17-hydroxyprogesterone, and androgen (dehydroepiandrosterone sulfate or androstenedione) concentrations were consistently high in unaffected and affected Pomeranians, compared with values in control dogs.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum vascular endothelial growth factor in dogs with haemangiosarcoma and haematoma

Splenic haemangiosarcomas are frequently seen in dogs. Because of their bad prognosis differentiation from other benign splenic lesions are of prognostic importance.     

Stimulation of pig growth performance by porcine growth hormone and growth hormone-releasing factor

The current study was undertaken to determine the effects of human growth hormone-releasing factor [hpGRF-(1-44)-NH2] on growth performance in pigs and whether this response was comparable to exogenous porcine growth hormone (pGH) treatment. Preliminary studies were conducted to determine if GRF increased plasma GH concentration after iv and im injection and the nature of the dose response. Growth hormone-releasing factor stimulated the release of pGH in a dose-dependent fashion, although the individual responses varied widely among pigs. The results from the im study were used to determine the dose of GRF to use for a 30-d growth trial. Thirty-six Yorkshire-Duroc barrows (initial wt 50 kg) were randomly allotted to one of three experimental groups (C = control, GRF and pGH). Pigs were treated daily with 30 micrograms of GRF/kg body weight by im injection in the neck. Pigs treated with pGH were also given 30 micrograms/kg body weight by im injection. Growth rate was increased 10% by pGH vs C pigs (P less than .05). Growth rate was not affected by GRF; however, hot and chilled carcass weights were increased 5% vs C pigs (P less than .05). On an absolute basis, adipose tissue mass was unaffected by pGH or GRF. Carcass lipid (percent of soft-tissue mass) was decreased 13% by GRF (P less than .05) and 18% by pGH (P less than .05). Muscle mass was significantly increased by pGH but not by GRF. There was a trend for feed efficiency to be improved by GRF; however, this was not different from control pigs. In contrast, pGH increased feed efficiency 19% vs control pigs (P less than .05). Chronic administration of GRF increased anterior pituitary weight but did not affect pituitary GH content or concentration. When blood was taken 3 h post-injection, both GRF- and pGH-treated pigs had lower blood-urea nitrogen concentrations. Serum glucose was significantly elevated by both GRF and pGH treatment. This was associated with an elevation in serum insulin. These results indicate that increasing the GH concentration in blood by either exogenous GH or GRF enhances growth performance. The effects of pGH were more marked than for GRF. Further studies are needed to determine the optimal dose of GRF to administer in growth trials and the appropriate pattern of GRF administration in order to determine whether GRF will enhance pig growth performance to the extent that exogenous pGH does.     

根瘤菌与固氮菌联合对毛叶苕子的促生效果

利用前期筛选的具有优良固氮活性的巨大芽孢杆菌菌株N3和豌豆根瘤菌菌株Vic5,研究单一及复合接种对毛叶苕子的促生效果及对土壤性质的影响.结果表明:相比不接菌处理CK,单一接种N3能显著提高毛叶苕子根瘤固氮酶活性,单一接种Vic5能显著提高毛叶苕子地上部生物量、结瘤数和根瘤固氮酶活性,Vic5处理下毛叶苕子地上部生物量、...