排序方式： 共有33条查询结果，搜索用时 312 毫秒
1.
King RH Campbell RG Smits RJ Morley WC Ronnfeldt K Butler K Dunshea FR 《Journal of animal science》2000,78(10):2639-2651
Sixty male and 60 female crossbred pigs were allocated to an experiment to investigate the effects of porcine somatotropin (pST) administration (0 or 6 mg/d) and dietary lysine content on growth performance, tissue deposition, and carcass characteristics over the live weight range of 80 to 120 kg. Pigs receiving pST were given diets containing 6.9, 7.8, 8.8, 9.7, 10.6, or 11.5 g lysine/kg, whereas control pigs received diets containing 4.8, 5.8, 6.9, 7.8, 8.8 or 9.7 g lysine/kg. These dietary levels ranged from 0.40 to 0.70 g available lysine/MJ of DE for pST-treated pigs and from 0.28 to 0.58 g available lysine/MJ of DE for control pigs. Pigs were individually housed in pens, and there were five replicates of each treatment. All diets contained 14.5 MJ of DE/kg and were offered for ad libitum consumption to pigs between 80 and 120 kg live weight. Growth rate increased exponentially and food conversion ratio (FCR) decreased exponentially with increasing levels of lysine. In addition, there was a significant sex x pST interaction such that pST reduced the sex difference in FCR. Growth rate was faster in boars than in gilts and was increased by pST at the higher levels of dietary lysine. Similarly, FCR was lower for boars than for gilts and was decreased by pST at the higher dietary lysine levels. The optimum growth rate and FCR were defined as the lysine level at which growth rate and FCR were 95% and 105%, respectively, of the lysine plateau. The optimum growth rate and FCR were achieved at similar dietary lysine contents and were approximately 0.35 and 0.52 g available lysine/MJ of DE for control and pST-treated pigs, respectively. Protein deposition in the carcass increased exponentially with increasing dietary lysine level, was higher in boars than in gilts, and was increased by pST at the higher dietary lysine contents. Sex had no effect on dietary lysine required to maximize protein deposition. The dietary lysine contents required to ensure 95% of plateau protein deposition of 104 and 153 g/d were 0.39 and 0.55 g available lysine/MJ of DE for control and pST-treated pigs, respectively. The increase in lysine requirement with pST seems to be commensurate with the increase in protein deposition. 相似文献
2.
Dietary nano-chromium tripicolinate increases feed intake and decreases plasma cortisol in finisher gilts during summer 总被引：1，自引：1，他引：0
Alex Tsungyu Hung Brian Joseph Leury Matthew Allen Sabin Cherie Louise Collins Frank Rowland Dunshea 《Tropical animal health and production》2014,46(8):1483-1489
Chromium (Cr) is an essential mineral element and has been used in pig diets to improve growth performance, insulin sensitivity, immune response and carcase traits and to reduce heat or other stress responses. The aims of thiss study were to determine the impact of nano-sized chromium tripicolinate (nCrPic) on growth performance, feed efficiency and carcase characteristics of finisher gilts during the summer period. A total of 60 finisher Large White x Landrace gilts were stratified on initial weight and then within strata randomly allocated into two treatment groups in three replicates during mid-summer for 28 days. All pigs were housed in individual pens and had ad libitum access to feed and water. Pigs were fed either a control finisher diet (wheat-based diet containing 13.8 MJ digestible energy (DE) per kilogram and 0.56 g available lysine/MJ DE) or a control diet containing 400 ppb Cr as nCrPic. Dietary nCrPic supplementation increased feed intake by 6 % over the entire study (P?=?0.05). In particular, dietary nCrPic increased average daily feed intake (ADFI) by 8 % (P?=?0.02) during the final 2 weeks of the study. Moreover, dietary nCrPic tended to improve average daily feed (ADFI) over the entire study (P?=?0.09). However, there were no significant effects of nCrPic on feed conversion ratio (FCR), final weight, hot standard carcase weight (HCWT), P2 depth or dressing percentage. Plasma cortisol was decreased by 25 % (P?=?0.06) by dietary nCrPic supplementation. However, there were no effects of nCrPic on plasma glucose, insulin and nonesterified fatty acids (NEFA), might because of the higher feed intake. In conclusion, this study demonstrates that dietary nCrPic supplementation at 400 ppb can increase feed intake in finisher gilts during mid-summer, suggesting that nCrPic can ameliorate some of the negative effects of heat stress in pigs, possibly via decreased of circulating cortisol. 相似文献
3.
Petra FRÝDLOVÁ Jan HNÍZDO Lenka CHYLÍKOVÁ Olga ŠIMKOVÁ Veronika CIKÁNOVÁ Petr VELENSKÝ Daniel FRYNTA 《Integrative zoology》2013,8(Z1):39-45
Blood cell morphology and count are not uniform across species. Recently, between‐species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa, and this finding was interpreted in the context of the metabolic theory. In the present study, we examined the numbers and the size of blood cells in 2 species of monitor lizards, the mangrove‐dwelling monitor (Varanus indicus) and the savannah monitor (V. exanthematicus), and we compared these traits in individuals of different body size. The results revealed that during the course of ontogeny, the size of red blood cells increases with body mass. Because the mass‐specific metabolic rate decreases with body size and the cell volume‐to‐surface ratio decreases with the cell size, changes in the erythrocyte size might be the result of oxygen transport adjustment. 相似文献
4.
The growth rate of the young pig is generally much less than its potential and may be constrained by endocrine status as well as by nutrient intake. The aim of this study was to determine whether porcine somatotropin (pST) could increase growth in the nursing pig. Fourteen sows nursing litters of 6 (n = 7) or 12 (n = 7) piglets were utilized to establish a high and low plane of nutrition for sucking pigs. On Day 4 of lactation, the median two male pigs from each litter were randomly allocated to one of two doses of pST (0 or 60 micrograms/kg/d) until weaning on Day 31. Pigs were bled on Days 4, 13, 22, and 31 of lactation and the plasma was analyzed for insulin-like growth factor (IGF)-I, IGF-II, and IGF binding protein-3 (IGFBP-3). Pigs were weaned into conventional accommodation and further weighed on Days 63, 91, and 119. Pigs from litters of 6 grew more quickly and weighed 2.2 kg (P = 0.01) and 3.5 kg (P = 0.04) more than pigs from litters of 12 at 31 and 63 d of age, respectively. There was no effect of pST on preweaning growth of sucking pigs (261 vs. 258 g/d, P = 0.68), although growth rate increased in the final 3 d before weaning at 31 d (241 vs. 294 g/d, P = 0.01). IGFBP-3 was greater (1.09 vs. 0.78 micrograms/ml, P < 0.001), whereas IGF-I tended to be greater (206 vs. 176 ng/ml, P = 0.14), in pigs from the small litters. There was no effect of pST on plasma IGF-I (182 vs. 195 ng/ml, P = 0.454) or IGFBP-3 (0.93 vs. 0.94 microgram/ml, P = 0.85) concentrations. Plasma IGF-I and IGFBP-3 were highly correlated with the growth rate of nursing pigs (R = 0.638 and 0.756, respectively). There were no effects of pST (340 vs. 328 ng/ml, P = 0.48) or litter size (336 vs. 333 ng/ml, P = 0.88) on IGF-II. In conclusion, pST had no little or no effect on growth performance or plasma IGF-I, IGF-II, or IGFBP-3 in sucking pigs on either a high or low plane of nutrition. 相似文献
5.
Fan Liu Casie J Braden Robert J Smits Jessica R Craig David J Henman Chris J Brewster Rebecca S Morrison Rebecca Z Athorn Brian J Leury Weicheng Zhao Jeremy J Cottrell Frank R Dunshea Alan W Bell 《Journal of animal science》2021,99(9)
Sows mated in summer produce a greater proportion of born-light piglets (<1.1 kg) which contributes to increased carcass fatness in the progeny population. The reasons for the low birth weight of these piglets remain unclear, and there have been few successful mitigation strategies identified. We hypothesized that: 1) the low birth weight of progeny born to sows mated in summer may be associated with weight loss during the previous summer lactation; and 2) increasing early gestation feed allowance for the sows with high lactational weight loss in summer can help weight recovery and improve progeny birth weight. Sows were classified as having either low (av. 1%) or high (av. 7%) lactational weight loss in their summer lactation. All the sows with low lactational weight loss (LLStd) and half of the sows with high lactational weight loss received a standard gestation feeding regime (HLStd) (2.6 kg/d; day 0–30 gestation), whereas the rest of the sows with high lactational weight loss received a compensatory feed allowance (HLComp) (3.5 kg/d; day 0–30 gestation). A comparison of LLStd (n = 75) versus HLStd sows (n = 78) showed that this magnitude of weight loss over summer lactation did not affect the average piglet or litter birth weight, but such results may be influenced by the higher litter size (P = 0.030) observed in LLStd sows. A comparison of HLStd versus HLComp (n = 81) sows showed that the compensatory feeding increased (P = 0.021) weight gain of gestating sows by 6 kg, increased (P = 0.009) average piglet birth weight by 0.12 kg, tended to reduce (P = 0.054) the percentage of born-light piglets from 23.5% to 17.1% but reduced the litter size by 1.4 (P = 0.014). A subgroup of progeny stratified as born-light (0.8–1.1 kg) or -normal (1.3–1.7 kg) from each sow treatment were monitored for growth performance from weaning until 100 kg weight. The growth performance and carcass backfat of progeny were not affected by sow treatments. Born-light progeny had lower feed intake, lower growth rate, higher G:F, and higher carcass backfat than born-normal progeny (all P < 0.05). In summary, compensatory feeding from day 0 to 30 gestation in the sows with high weight loss during summer lactation reduced the percentage of born-light progeny at the cost of a lower litter size, which should improve growth rate and carcass leanness in the progeny population born to sows with high lactational weight loss. 相似文献
6.
Infectious Ovine Keratoconjunctivitis (IOK) is a contagious ocular disease of sheep. A range of organisms have been observed as the aetiological agents of IOK. In this study, the presence of chlamydial pathogens (C. pecorum, C. abortus, C. psittaci) in conjunctival swabs was tested for. The swabs were collected from sheep with varying grades of IOK in an Australian pre‐export feedlot. The sheep had been rejected from a shipment because of the eye disease. The relative contribution of chlamydial pathogens to IOK and the rejection of animals was evaluated. In total, 149 conjunctival swabs were taken from rejected sheep (IOK Grades 1 to 6; n = 126) as well as those with healthy eyes (Grade 0; n = 23). Screening for chlamydial pathogens was done using species–specific qPCR assays. Chlamydial DNA was detected in 35.6% (53/149) of conjunctival samples. C. pecorum was the most predominant species with an overall prevalence of 28.9% (43/149). C. psittaci prevalence was 6.7% (10/149). Both organisms were detected in healthy as well as IOK‐affected eyes. All swabs tested negative for C. abortus. The results from this study demonstrate that Chlamydia spp can be readily detected in sheep presenting with IOK. The zoonotic C. abortus was not detected in any of the samples in this study, providing further evidence to the suggestion that this pathogen remains absent from Australia. Although the exact contribution of Chlamydia spp in the IOK pathogenesis is unclear, such studies are anticipated to be of benefit to Australian domestic and live export production systems. 相似文献
7.
PB Fernandes KO Marques FR de Araujo Neto DP de Oliveira NA Hurtado‐Lugo RR Aspilcueta‐Borquis H Tonhati 《Reproduction in domestic animals》2016,51(3):428-434
Because of the importance of reproduction in stock breeding systems, it is necessary to find selection criteria that increase reproductive efficiency. The aim of this study was to estimate genetic parameters for the probability of conception on first service (PROB) in Murrah heifers, and its association with other traits of economic interest [age at first calving (AFC), service period, calving interval and milk yield at 270 days], with the purpose of evaluating their use as selection criteria. Reproductive information and first lactation records of 1200 Murrah heifers were used to perform two‐trait analyses between PROB and the other characteristics. Bayesian inference was used to estimate the variance components, considering PROB as threshold and the other as linear factors. The results demonstrate that this trait has heritability of 0.15, indicating the possibility of a genetic gain by using it for selection. With respect to the genetic correlation estimates, the only high‐magnitude association was with AFC (?0.899), which is the current criterion indicating sexual precocity of females. In the light of the parameters estimated, the first‐service pregnancy rate is an alternative for indication of sexual precocity, although presenting a smaller genetic gain than the current standard AFC. Nevertheless, additional research should be conducted regarding this trait to assess the economic importance of its use in dairy buffalo production systems. 相似文献
8.
Soybean seed coat chitinase as a defense protein against the stored product pest Callosobruchus maculatus 
下载免费PDF全文
下载免费PDF全文 9.
Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity 下载免费PDF全文
下载免费PDF全文 FCA Sousa GT Pessoa LS Moura JR Araújo RPS Rodrigues MAPS Barbosa AN Diniz AB Souza EG Silva LU Lucena MP Sanches OF Silva‐Filho PC Guerra JM Sousa WC Neves FR Alves 《Reproduction in domestic animals》2017,52(1):60-66
The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages. 相似文献
10.
Lealiifano AK Pluske JR Nicholls RR Dunshea FR Campbell RG Hennessy DP Miller DW Hansen CF Mullan BP 《Journal of animal science》2011,89(9):2782-2792
The objective of this study was to evaluate whether altering the timing of the secondary anti-gonadotropin-releasing factor (GnRF) immunization closer to slaughter in male finishing pigs would reduce the increase in P2 fat depth (6.5 cm from the midline over the last rib), while still limiting the incidence of boar taint. Entire male pigs are immunized against GnRF to reduce the concentration of testicular steroids that in turn limits the incidence of boar taint. Additionally, testicle measurements and color measurements were taken to examine whether they could be used to differentiate nonimmunized entire males from immunized male pigs. A total of 175 Large White × Landrace entire male pigs aged 16 wk (59 kg of BW) were used in a completely randomized design with 5 treatment groups based on the time that pigs received the secondary immunization before slaughter. Pigs were housed in groups of 7 and randomly allocated to 1 of 5 treatments with 5 replicates per treatment. The treatment groups were as follows: no secondary immunization before slaughter, and the secondary immunization given at 2, 3, 4, or 6 wk before slaughter. The P2 fat depth levels were reduced (P = 0.054) with the secondary immunization closer to slaughter (11.7, 11.3, 12.8, 12.6, and 13.7 mm for no secondary immunization, secondary immunization at 2, 3, 4, and 6 wk before slaughter, respectively). Androstenone concentration did not exceed the generally accepted industry sensory threshold of 1.0 μg/g of fat, and both androstenone concentration in the adipose tissue and testosterone concentrations in the blood were suppressed (P < 0.001) in all immunized pigs regardless of timing of the secondary immunization compared with pigs that did not receive the secondary immunization. Skatole concentration of all pigs in the experiment did not exceed the generally accepted industry sensory threshold of 0.2 μg/g. Testes weight was reduced (P < 0.001) with increased time between slaughter and the secondary immunization. Immunized pigs, regardless of time before slaughter, had greater L* (lightness) and b* (yellowness) color of the testicle surface (P < 0.001 and P = 0.020, respectively), and less a* (redness) color compared with entire males (P < 0.001). The study provides further evidence of the efficacy of the anti-GnRF immunization and indicates that the secondary immunization can be moved closer to slaughter, while still limiting the incidence of boar taint. Testicle measurements and color measurements together could provide a method of discrimination between carcasses from immunized entire males clear of boar taint and tainted carcasses. 相似文献