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21.
The experiment consisting of 7 days of digestibility and 90 days of feeding trial was conducted at Wogda (Ethiopia) to determine the effect of supplementation of graded levels of concentrate mix (CM) on feed intake, digestibility, and body weight (BW) change in hay-based feeding of Simada sheep. Twenty-yearling Simada sheep with a mean initial BW of 17.9 ± 0.81 kg (mean ± SD) were used in randomized complete block design arranged into five blocks of four animals. The four dietary treatments that consisted of hay alone (T1), hay +150 g dry matter (DM; T2, low), hay +250 g DM (T3, medium), and hay +350 g DM (T4, high) CM were randomly assigned to each sheep within a block. The CM consisted of wheat bran (WB), noug seed (Guizotia abyssinica) meal and safflower (Carthamus tinctorius) seed meal at the ratio of (2:1:1), respectively. Supplementation with T2 and T3 increased (P < 0.001) total DM and organic matter intake than the control treatment. Overall, supplementation improved (P < 0.001) crude protein intake, digestibility, feed conversion efficiency, BW gain, and profitability compared to the control, whereas sheep on the high than the low and medium level of supplementation performed better in these parameters among the supplemented treatments. From the results of this study, T4 is recommended as the best level of supplementation since it resulted in better nutrient utilization, animal performance, and profitability.  相似文献   
22.
Nematode infections are a serious constraint to pig production, especially where free range pig keeping is practiced. This study investigated the epidemiology of nematodes in free range pigs in Busia District, Kenya. Three hundred and six pigs from 135 farms were sampled for faeces that were analysed for nematode eggs per gram (EPG) of faeces using the McMaster technique. The nematode eggs were also identified to genus and species based on morphology. A questionnaire on risk factors was also administered to the pig owners. The overall prevalence and mean nematode EPG were 84.2% and 2,355, respectively. The nematode eggs were identified as those belonging to Oesophagostomum spp. (75%), Strongyloides ransomi (37%), Ascaris suum (18%), Metastrongylus spp. (11%), Trichuris suis (7%) and Physocephalus sexalatus (3%). The prevalence of nematodes was positively correlated (p < 0.05) with the amount of rainfall in the division of the pigs' origin (all nematodes except S. ransomi). The prevalence of nematodes was also associated with the age of the pigs. A lower burden of nematodes was associated (p < 0.05) with a history of deworming (A. suum) and the provision of night housing (S. ransomi and Metastrongylus spp.). In conclusion, this study has provided information on nematode infections and the associated risk factors for free range pigs in Busia District, which can be used when implementing integrated control measures.  相似文献   
23.
A ciliate protozoa suppression can reduce methane production increasing the energy efficiency utilization by ruminants. The physicochemical characteristics of rumen fluid and the profile of the rumen protozoa populations were evaluated for sheep fed banana leaf hay in replacement of the Cynodon dactylon cv. vaqueiro hay. A total of 30 male sheep were raised in intensive system during 15 days of adaptation and 63 days of experimental period. The animals were distributed in a completely randomized design that included six replicates of five treatments with replacement levels (0, 25, 50, 75, and 100%) of the grass vaquero for the banana leaf hay. Samples of fluid were collected directly from the rumen with sterile catheters. Color, odor, viscosity, and the methylene blue reduction potential (MBRP) were evaluated and pH estimated using a digital potentiometer. After decimal dilutions, counts of genus protozoa were performed in Sedgewick Rafter chambers. The averages of pH, MBRP, color, odor, and viscosity were not influenced by the inclusion of the banana leaf hay. However, the total number of protozoa and Entodinium spp. population significantly decreased at 75 and 100% inclusions of banana leaf hay as roughage.  相似文献   
24.
A cross-sectional study was carried out to determine the status of Brucella infection in one-humped (Dromedary) camels in the North and Central senatorial districts of Katsina State, Nigeria. Nine hundred and eighty serum samples from live and slaughtered camels were tested. Modified Rose Bengal plate test (RBPT) and serum agglutination test (SAT) with ethylenediaminetetraacetic acid, (EDTA) were used as screening and standard tests, respectively. The prevalence of Brucella antibodies were 110 (11.2%) and 103 (10.5%) for RBPT and SAT, respectively. Of the 472 and 508 serum samples tested from the herds and abattoirs, respectively, 63 (13.3%) and 47 (9.3%) were positive by RBPT while 62 (13.1%) and 41 (8.1%) were positive by SAT, respectively. Based on the results, it was concluded that Brucella antibodies were present in camels in the study area. Poor management practices and mixing of camels with other species of livestock as well as unrestricted movement of camels were proposed to be the reasons for the prevalence of the disease in the study area. In view of the public health importance of the disease, it is recommended that there is the need to develop a strategic plan to decrease spread of brucellosis in the study area.  相似文献   
25.
26.
In most mammals, glucokinase (GK) acts as a hepatic “glucose sensor” that permits hepatic metabolism to respond appropriately to changes in plasma glucose concentrations. GK activity is potently regulated by the glucokinase regulatory protein (GKRP), which is encoded by the GCKR gene. GKRP binds GK in the nucleus and inhibits its activity. GK becomes active when it is released from GKRP and translocates to the cytosol. Low glucokinase (GK) activity is reported to be a principal feature of feline hepatic carbohydrate metabolism but the molecular pathways that regulate GK activity are not known. This study examined the hypothesis that species-specific differences in GKRP expression parallel the low GK activity observed in feline liver. Hepatic GKRP expression was examined using RT-PCR, immunoblot, and confocal immunomicroscopy. The results show that the GCKR gene is present in the feline genome but GCKR mRNA and the GKRP protein were absent in feline liver. The lack of GKRP expression in feline liver indicates that the low GK activity cannot be the result of GKRP-mediated inhibition of the GK enzyme. However, the absence of the permissive effects of GCKR expression on GK expression and activity may contribute to reduced GK enzyme activity in feline liver. The study results show that the cat is a natural model for GCKR knockout and may be useful to study regulation of GCKR expression and its role in hepatic glucose-sensing and carbohydrate metabolism.  相似文献   
27.
The effect of spineless cactus intake (Opuntia ficus-indica) on blood glucose (BG) levels in lactating sows and its impact on daily and total feed intake (dFI?1 and TFI, respectively), body weight loss (BWL), and weaning-estrus interval length (WEI) were evaluated. Thirty-four hybrid (Yorkshire × Landrace × Pietrain) sows in lactation phase were used. Sows were divided into two groups: G1 (n = 17) where they received commercial feed and G2 (n = 17) provided with commercial feed plus an average of 2.0 ± 0.5 kg spineless cactus, based on a sow’s body weight. The variables evaluated were BG, dFI?1, TFI, BWL, and WEI. Statistical analysis was performed by using a fixed and mixed model methodology, under a repeated measurements experiment. Group effects were found on all analyzed variables (P < 0.05). The BG was lower in G2 (55.2 and 64.5 mg/dL pre- and post-prandial, respectively), compared to that in G1 (70.9 and 80.1 mg/dL pre- and post-prandial, respectively) (P < 0.05). G2 showed better performance than G1 for dFI?1, BWL, and WEI (P < 0.05) whose averages were 5.5 ± 1.8 kg, 7.4 ± 4.5%, and 5.3 ± 1.2 days, respectively. Averages for these variables in G1 were 4.7 ± 1.5 kg, 16.8 ± 4.6%, and 6.1 ± 1.6 days, respectively. Intake of spineless cactus reduced BG levels in lactating sows, generating greater dFI?1, lower BWL at the end of lactation, and a lower WEI.  相似文献   
28.
The anaphylactic reactions in cattle following leptospira vaccination mostly booster dose in different parts of Iran have been reported. The serum proteins as allergic substances are components of liquid phase of the vaccine. Therefore, the vaccine was modified by washing the whole cultures by centrifugations. The modified vaccine was safe in laboratory animals and cattle as well as under field conditions. Microagglutination test revealed a similar pattern of antibody response to the three Leptospira interrogans serovars (Canicola, Grippotyphosa, and Sejro hardjo) in all vaccinated cattle groups while was higher than the response of control animals. The results of the present investigation revealed that we can minimize postvaccination shock in vaccinated cattle populations with removing the shock proteins.  相似文献   
29.
The herds of 95 families were monitored for 1 year in eight villages in the cotton-growing region of southern Mali. In 2006–2007, reproduction performances were average, with 0.54 calvings/year per cow, and mortality was low. Herd numerical productivity is not very high, less than 0.13/year, because of the high proportion of males kept for animal draught. Depending on the herd size, the behaviour of the families differs, in terms of off-take and in-take of animals. Families that only have one or two draught animals seek to increase their animal draught capacity, with a negative net off-take (−0.13/year). Families with two to three cows have a very low net off-take (0.02/year), with culling of adult animals compensated by purchase. They therefore capitalised this year, with an annual herd growth of 8%. Families with a very large herd (20 to 50 cows) take off more of their stock, with a net off-take of 0.08/year (very few animal purchases) and make a stock growth of 5%. And finally, families with an average-sized herd (6 to 19 cows) take off the whole of the year’s production, with a net off-take of 0.11/year and a nil stock growth rate. The use of a demographic model made it possible to measure the sensitivity of the productivity rate to the different demographic parameters.  相似文献   
30.
The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment.  相似文献   
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