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1.
An enriched environment is widely used to improve domestic animals’ welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs.  相似文献   
2.
The aim of this study was to analyse the association between single-nucleotide polymorphisms within INHA and ACVR2B and litter size in Dazu black goats. In total, twenty-two SNPs were genotyped in 190 individuals by SNaPshot and resequencing. The results showed that three SNPs (SNP_1, SNP_12 and SNP_13 in this study) were detected to have significant additive genetic effect on the recorded goat litter size (p < .05). The SNP_1 (NC_030809.1), a non-synonymous substitution of G for T at chr2-g. 28314990 in the exon 2 of INHA gene (NM_001285606.1), resulted in homozygote 2 (HOM2) contributed 0.25 and heterozygote (HET) contributed 0.12 larger litter than homozygote 1 (HOM1). Meanwhile, SNP_12 (Chr22-g. 11721225 A > T) and SNP_13 (Chr22-g. 11721227 A > C) (NC_030829.1) simultaneously mutated at the first and third position of a triplet AAA (lysine, K) in the exon 4 of ACVR2B gene (XM_018066623.1) had estimated genetic effects of HOM1 (0.00) and HOM2 (0.03) larger than HET (−0.12). In conclusion, one SNPs (chr2-g. 28314990 T > G) within the exon 2 of INHA and two SNPs (Chr22-g. 11721225 A > T and Chr22-g. 11721227 A > C) i n the exon 4 of ACVR2B gene were highly recommended as candidate markers of litter size in Dazu black goats. A large-scale association study to assess the impact of these variants on litter size is still necessary.  相似文献   
3.
In a feeding trial lasting for months Halothane-positive fattening pigs were put on a diet containing different concentrations of vitamin E and selenium. After a Myostress application vitamin E and selenium were additionally injected in order to examine stress resistance (CK-test) and regenerative capacity (histological examination of Musculus longissimus dorsi) of skeletal muscle. The study revealed that neither high dietary levels of vitamin E/selenium nor a vitamin E/selenium treatment applied after stress are capable of preventing stress related myopathy nor can they influence its healing up favourably.  相似文献   
4.
The aerobic bacterial flora of the genital tract was characterized in 15 stud dogs in an 18-month study. The dogs represented 4 breeds and were from 3 kennels. Bacterial samples from the prepuce and semen were collected every month, except in connection with matings, when they were collected weekly (464 samples). The dogs that were included all mated at least once during the study. The mean pregnancy rate, litter size, and pup mortality for the bitches with which they had mated were all within normal limits. The most frequent bacteria isolated from the prepuce and semen were Pasteurella multocida, beta-hemolytic streptococci, and Escherichia coli. There was a tendency for breeds to differ in frequency of the most common bacterial species. Bacterial culture yielded no aerobic growth in 14.2% of the preputial samples and 69.8% of the semen samples. Bacteria were transferred between dog and bitch at mating. In this study of healthy breeding dogs, neither the fertility of the dog nor that of the bitch was affected by the bacteria transferred.  相似文献   
5.
6.
Eradication of lice in cattle.   总被引:8,自引:0,他引:8  
The purpose of this field study was to develop and evaluate eradication as a strategy to control lice in cattle. Thirty-three herds of cattle were selected and observed during a period of two and a half years. Before eradication, biting lice (Damalinia bovis) were present in 94% of the herds and 27% of the animals. Sucking lice (Linognathus vituli) were present in 42% of the herds and 5% of the animals. These levels were very similar to those reported from other countries in Northern Europe. The eradication strategy was successful in 28 of 33 herds, but lice were still present in 5 herds 3 to 6 months after treatment. Biting lice were present in all these 5 herds, sucking lice were present in 3 herds. During the next 12 months, nine of the 28 herds were reinfected with lice. Six herds were reinfected with just biting lice, 2 herds with just sucking lice and one herd was reinfected with both. There was no significant difference between the 2 louse species regarding the risk of unsuccessful eradication or reinfection. The only significant risk factor for reinfection was either purchase of livestock or use of common pasture, combined with failure in pre-treatment of newly introduced animals.  相似文献   
7.
OBJECTIVE: To determine epidemiologic, clinical, and pathologic characteristics of inflammatory mammary carcinoma (IC) in dogs. DESIGN: Retrospective study. ANIMALS: 33 dogs with IC and 153 dogs with malignant mammary tumors other than IC. PROCEDURES: Medical records were reviewed, and signalment, history, physical examination findings, and results of thoracic radiography and necropsy were obtained. RESULTS: 33 of 436 (7.6%) dogs examined at a veterinary teaching hospital because of dysplasia or tumors of the mammary glands and 33 of 186 (17.7%) dogs with at least 1 malignant tumor had IC. Thirty-two of the 33 dogs were sexually intact. Dogs with IC were significantly older than were dogs with other malignant mammary tumors, and in dogs with IC, the tumor was initially noticed a mean of 52 days after the beginning of the last observed estrus, whereas in dogs with other mammary tumors, the tumor was initially noticed a mean of 137 days after the beginning of the last observed estrus. Dogs with IC were more likely to be anorectic and to have generalized weakness, weight loss, and thoracic metastases. Dogs with IC survived a mean of 25 days with palliative treatment. Histologically, involvement of dermal lymphatic vessels was identified in 14 of 19 (74%) dogs with IC. Two clinical forms of IC (primary and secondary) were identified. Dogs with primary IC had a worse clinical condition. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that IC is an uncommon but distinct entity in dogs. A histologic finding of dermal lymphatic involvement should be considered a hallmark for the pathologic diagnosis of IC in dogs.  相似文献   
8.
The article considers the attractions and dangers of homeopathic therapy from the view of a pharmacologist. Homeopathic drugs may exert pharmacodynamic (but also toxic) effects at low dilutions (D0-D6), but there is no scientific proof for specific effects of higher dilutions except for substances with a high toxic potential. Most homeopathic drugs have no reasonable basis for clinical use but, in case of toxic compounds, especially those with carcinogenic or allergic potential, homeopathy may bear risks for the animal and, because of residues in food animals, also for humans. Thus, homeopathic treatment should not be used when effective conventional treatments are available, and the use of homeopathic drugs with toxic potential should be avoided.  相似文献   
9.
10.
鸭瘟病毒的PCR检测及其产物分析   总被引:6,自引:0,他引:6  
根据基因库中已有的鸭瘟 Ul6的序列 ,合成一对引物 ,对 3株鸭瘟病毒进行 PCR扩增 ,均扩增出大小约 42 0 bp的特异性片段。进行测序 ,结果表明 3个毒株扩增后的片段均为 42 1bp。经重复实验后确定最佳反应条件 ,按该条件对两例临床病料进行检测 ,结果均出现大小约为 42 0 bp的特异片段。PCR产物与 L ake Andes株的相关序列比较 ,广东毒株与 L ake Andes株同源性较高  相似文献   
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