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101.
Concepta McManus Helder Louvandini Rosilene Gugel Luiz Cláudio Bastos Sasaki Eliandra Bianchini Francisco Ernesto Moreno Bernal Samuel Rezende Paiva Tiago Prado Paim 《Tropical animal health and production》2011,43(1):121-126
The objective of this study was to evaluate and compare physical parameters in groups of sheep with different phenotypic characteristics
in the Centre-west region of Brazil. Five groups of sheep, with nine animals per group, were selected, three groups of Santa
Inês animals with different coat colours (white, brown and black), one group with crossbred animals (Santa Inês × Bergamasca)
and one group with animals of the Bergamasca breed. The following traits were evaluated: coat thickness, number and length
of hair, pigmentation level in the coat and the skin as well as the percentage area of sweats glands in the skin tissue, carried
out by histological analysis. The number of hairs and the area of sweats glands were not significantly different between the
evaluated groups. The Bergamasca breed showed low pigmentation of the skin and long hairs. The levels of pigmentation of the
hair and of the skin were highly correlated. Between the Santa Inês groups, the group with white hair showed the better parameters
for heat adaptation, while the brown hair group showed the lower heat adaptation when compared with another hair breed groups. 相似文献
102.
The aim of this study was to determine the fattening performance and the slaughter and carcass characteristics of Akkeçi (Saanen × Kilis (B1) crossbred) male kids raised in individual crates (IC) or in group pen housing (GP). In both GP and IC groups, total 13 heads of male kids, whose initial body weights were 21.43 ± 1.03 kg and 20.61 ± 0.98 kg, respectively, evaluated for their fattening performances. After 56 days of the fattening period, the final body weights and average daily weight gains of the GP and IC kids were recorded as 30.84 ± 0.82 kg and 25.84 ± 0.76 kg; 182.42 ± 14.77 g and 92.09 ± 13.76 g, respectively (P < 0.001). Adrenal gland weights of the GP and IC groups were similar as 1.66 ± 0.25 g and 1.77 ± 0.22 g, respectively. Although, the carcass conformation of kids was similar between groups, there were significant differences between GP and IC groups for some slaughter and carcass characteristics. In general, although housing kids reared in individual crates provides opportunity to individually feed and monitor a kid, the results obtained from the individual crates in the present study were not satisfactorily from the ethological and production points of view. 相似文献
103.
Segura-Correa JC Ek-Mex EJ Alzina-López A Magaña-Monforte JG Sarmiento-Franco L Santos-Ricalde RH 《Tropical animal health and production》2011,43(6):1191-1194
The objective of this study was to determine the effect of some factors on the length of productive life (LPL), the number
of parities (NP), and the culling interval (CI) of sows. The information from 2003 to 2009 of 3,746 sows with LPL and NP records
and 5,819 sows with CI records from the four farms of Yucatan, Mexico was used. LPL was defined as the number of days between
the first farrowing and culling or death and CI as the number of days between the last farrowing and culling. To determine
the effects of farm, litter size at first farrowing (LSF1) and age at first farrowing (AF1) on LPL and NP, and of farm, LSF1
and culling reason on CI general linear models were used. Means and standard errors for LPL, NP, and CI were 496.4 ± 8.42 days,
3.35 ± 0.04 parities, and 48.3 ± 0.52 days, respectively. All factors had significant effects (P < 0.05) on LPL, NP, and CI. The sows from farm 2 stayed longer (806.0 days) and had more parities (5.25) than the sows from
the other farms. Sows with the smallest litters (≤8 piglets) at first farrowing stayed the least time in the farm (675.1 days)
and had the fewest parities (4.49). Gilts farrowing the first time before 331 days of age stayed longer time in the farm (726.4 days)
and had more parities (4.81) in comparison with 331–348 and more than 348 days age groups. With respect to CI, the sows in
farm 3 stayed the longest time in the farm. Sows with more than five parities were culled sooner after their last farrowing.
In conclusion, differences between farms for LPL, PN, and CI were found. Females that farrowed at a short age and those with
large litters stayed longer in the herd. Old sows and those culled for reproductive reasons stayed the least time in the herd
after their last farrowing. 相似文献
104.
Mersha Chanie Tamiru Negash Samuel Bekele Tilahun 《Tropical animal health and production》2009,41(7):1309-1317
Commercial poultry production is one of the flourishing ventures of animal production in Ethiopia. It has been providing to
the demands of proteins at least to the urban population, though concurrent health constraints are hampering its intended
potential. This study reports the influence of infectious diseases in commercial broiler farms in central Ethiopia. In this
study, clinical signs, gross lesions, laboratory tests (serology, bacterial culture, histopathology and parasitology) and
farm management data were used to identify major causes of outbreaks in an age specific manner in broiler chickens in three
poultry farms in Debre Zeit, Central Ethiopia. The outbreaks detected in the farms were due to mycoplasmosis, salmonellosis,
colibacillosis, coccidiosis and infectious bursal disease. It is observed that the occurrence of concurrent diseases in the
farms significantly affects the productivity and health status of broilers. The risk factors that predispose birds to the
various infections in the different farms studied were also recorded. In addition, recommendations were also provided. 相似文献
105.
In this study, natural cycling of BoHV-1 infection was investigated in two groups of dairy cattle containing 2120 head. Group
1 comprised 127 animals and they were monitored for BoHV-1 infection virologically and serologically in six consecutive sampling
periods. It consisted of naive heifers between 6 and 8 months of age, while in group 2, age, sex and the BoHV-1 serostatus
of the animals were disregarded. The animals in group 1 were found to have seroconverted at the second sampling. Results of
the serological study showed slight antibody response after natural BoHV-1 infection in the herd and neutralizing titres fell
below protective levels in the 6–8 months after the peak. During the 2-year study period, one recurrence was detected after
primary infection. Virus isolation studies revealed a cytopathic effect indicative of BoHV-1 in two nasal swabs taken during
the fifth sampling period from animals with mild upper respiratory tract symptoms. As the study was carried out under natural
conditions, it is not known whether the viruses isolated were from recurrences or re-infections. Data from cross-neutralization
tests with herd isolates showed higher antibody response than those with the reference virus. The dynamics of BoHV-1 in both
groups were found to be statistically similar. 相似文献
106.
J. A. Mortenson E. H. Haq Khan I. Ali S. Manzoor A. Jamil M. Abubakar M. Afzal M. Hussain 《Tropical animal health and production》2017,49(4):691-695
In northern Pakistan, many farming communities rely on domestic yak (Bos grunniens) as a principle source of income. A 2006 participatory disease surveillance report from this region indicated that foot-and-mouth disease (FMD) is the most prevalent annual disease of yak. Our objectives of this study were to determine exposure levels of yak to FMD virus; implement a vaccination program based on current, regional FMD virus serotypes and subtypes; and quantify immune responses following vaccination. Blood samples were used to determine pre-vaccination exposure of animals to FMD virus by antibody presence to non-structural proteins of FMD virus using a 3-ABC trapping indirect ELISA. Vaccine used consisted of FMD serotypes ‘O’ (PanAsia-2), ‘A’ (Iran-05), and ‘Asia-1’ (Shamir), but changed later during the study to match newly circulating viruses in the country (‘O’-PanAsia-2; ‘A’-Turk-06 and Asia-1-Sindh-08). Three hundred sixty-three blood samples were tested from selected villages to determine pre-vaccination FMD virus exposure in yak with an average of 37.7%. Immune responses from initial vaccination and booster dose 30 days later showed clear protective levels (as mean percent inhibition) of antibodies against structural proteins of serotypes ‘O,’ ‘A,’ and ‘Asia-1.’ These responses remained above threshold positive level even at day 210 following initial vaccination. Results of sero-surveillance and anecdotal information of repeated FMD outbreaks demonstrate the persistence of FMD virus of yak in northern Pakistan. Laboratory results and field observations clearly indicated that yak can be protected against FMD with a good quality vaccine with FMD serotype(s) matching current, regionally circulating FMD virus. 相似文献
107.
Raj Sukhbir Singh B. K. Bansal D. K. Gupta 《Tropical animal health and production》2017,49(8):1623-1629
The present study was aimed to investigate the relationship between selected morphological traits of teat and subclinical mastitis (SCM) in Frieswal crossbred dairy cows. A total of 1040 quarters from 261 lactating cows were evaluated for teat shape (bottle/fleshy/collapsed/conical/normal/pencil and short), teat-end shape (dished/flat/funnel/pocketed/pointed and rounded), teat orientation (aligned/misaligned) and teat position (front and rear; left-sided and right-sided). Each udder quarter was screened with California Mastitis Test (CMT) for the purpose of defining quarter health status. Data were analysed using Chi-square test and multivariable logistic regression procedure. An overall prevalence of SCM (CMT positive) at quarter level was 30.6%. Most of the teats had normal or cylindrical shapes (48%), dished teat-ends (40.7%), and aligned (central or squared) in orientation (65%). At bivariable level, significant association of SCM with teat shape, teat position, teat orientation, parity, and stage of lactation was observed (P < 0.05 to P < 0.001). Teat-end shapes showed some association with SCM (P = 0.07). Results of multivariable analysis showed that pencil-shaped teats were least associated with SCM (P < 0.05) as compared to other teat shapes. Prevalence of SCM was also higher in rear teats (P = 0.015), misaligned teats (P = 0.01), and cows in second or higher parities (P < 0.01) and late stage of lactation (P < 0.001). The results of the present study indicate that selected morphological traits of teat are associated with SCM in Frieswal crossbred cows; therefore, selection towards desirable morphological traits could help reduce mastitis in this breed. 相似文献
108.
Fariba Ahmadi Morteza Zendehdel Vahab Babapour Negar Panahi Shahin Hassanpour Mina Khodadadi 《Veterinary research communications》2017,41(4):241-248
Melanocortin 3 and 4 receptors (MC3R and MC4R) are known as the main receptors for melanocortin-induced hypophagia in mammalian and poultry. Also, central glutamatergic system has mediatory role on function of the melanocortin system in some brain areas. So, the aim of the current study was to determine the role of MC3/MC4 receptors agonist on food intake and its interaction with glutamatergic in 3-h food-deprived (FD3) neonatal broilers. In experiment 1, chickens were intracerebroventricular (ICV) injected with control solution, MTII (MC3/MC4 receptors agonist; 2.45, 4.8 and 9.8 pmol). In experiment 2, control solution, SHU9119 (MC3/MC4 receptors antagonist; 0.5, 1 and 2 nmol) were ICV injected. In experiment 3, birds ICV injected with control solution, SHU9119 (0.5 nmol), MTII (9.8 pmol) and co-injection of the SHU9119 + MTII. Experiments 4–8 were similar to experiment 3, except birds injected with MK-801 (NMDA glutamate receptors antagonist, 15 nmol), CNQX (AMPA glutamate receptors antagonist; 390 nmol), AIDA (mGLUR1 glutamate receptors antagonist; 2 nmol), LY341495 (mGLUR2 glutamate receptors antagonist; 150 nmol) and UBP1112 (mGLUR3 glutamate receptors antagonist; 2 nmol) instead of SHU9119. Then, cumulative food intake was recorded until 120 min after injection. According to the results, dose dependent hypophagia observed after ICV injection of the MTII (p < 0.05). ICV injection of SHU9119 significantly increased food intake in birds (p < 0.05). Co-injection of SHU9119 + MTII significantly inhibited MTII- induced hypophagia in neonatal chicks (p < 0.05). In addition, hypophagia- induced by MTII was significantly attenuated with co-injection of MTII + MK-801(p < 0.05). These results suggested MC3 and MC4 receptors have inhibitory role on food intake and this effect is probably mediated by NMDA glutamate receptors in neonatal chickens. 相似文献
109.
Yongju Zhao Jiahua Zhang Hong Wei Xinming Sun Biao Mu Mingju Yu Lingbing Wang 《Tropical animal health and production》2010,42(6):1257-1262
Two experiments were undertaken to select the efficient method applied for goat estrous synchronization. In experiment 1, a total of 120 does (Capra hircus) were divided into five groups with a randomized block design, and the does of treatment 1 were synchronized by intravaginal sponges impregnated with 30 mg Levonorgestrel inserted for 10 days. Does of treatments 2, 3, and 4 were treated with further injection of 25 IU follicle-stimulating hormone (FSH), 0.05 mg prostaglandin F2 alpha (PGF2α), and 25 IU FSH + 0.05 mg PGF2α at sponge withdrawal, respectively. The does in the control group (n = 40) without estrous synchronization treatment and natural estrous does were observed. In experiment 2, a total of 140 does in five goat farms in breeding and non-breeding seasons were treated with the selective efficient procedure. The results presented that all the employed treatments were capable of inducing and synchronizing estrous goats. According to estrous response and economy, the use of intravaginal sponges impregnated with 30 mg Levonorgestrel and 0.05 mg PGF2α (treatment 3) is the first choice for estrous synchronization, and 95.0% of synchronized does demonstrated estrus, which was significantly higher than that of treatment 1 (P < 0.05) and control group (P < 0.01). The percentages of ovulating of treatments 3 and 4 were the same (95.0%), which were significantly higher than that of treatment 1 (P < 0.01). The ovulation rates among different groups were not significant (P > 0.05). When the selective procedure was applied to five goat farms, 85.7% (120/140) of does demonstrated estrus, and the kidding percentage, litter size, and prolificacy rate were 53.6%, 0.95, and 177%, respectively. 相似文献
110.
Ross G. Cooper Jaroslaw O. Horbańczuk Raul Villegas-Vizcaíno Salwa Kennou Sebei Aisha E. Faki Mohammed Khalid M. A. Mahrose 《Tropical animal health and production》2010,42(3):363-373
This work discusses some of the important considerations of wild ostrich evolution, behaviour and ecology, as items included
in ostrich production. In the process considerable research was conducted by collating information from peer-reviewed papers;
textbooks; manuals; and PubMed and Agricola searches. Selected areas reviewed included activity of ostriches; feeding and
water needs; sexual maturity; egg laying and natural incubation; selected physiological parameters; and predation. There is
an immediate and urgent need to conserve and protect the rapidly declining populations of wild ostriches with the committed
involvement of governments and funding bodies. 相似文献