Effect of Early Postpartum Ovulation on Fertility in Dairy Cows     

KN Galvo  M Frajblat  WR Butler  SB Brittin  CL Guard  RO Gilbert 《Reproduction in domestic animals》2010,45(5):e207-e211

Our objectives were to determine the effects of early ovulation on fertility and uterine health of dairy cows. Four hundred and forty‐five Holstein cows (185 primiparous and 260 multiparous) from five herds were used. Blood samples were collected at 21, 35 and 49 days in milk (DIM) and cows were considered to be cyclic at 21 DIM (Cyc21) if serum progesterone (P4) concentration was above 1 ng/ml, cyclic by 49 DIM (Cyc49) if P4 concentration was above 1 ng/ml at 35 or 49 DIM, or not cyclic (NotCyc) if P4 concentration was below 1 ng/ml at all sample times. Endometrial cytology for diagnosis of subclinical endometritis was examined at 49 DIM in a subset of 414 cows. Cows in the group Cyc21 had increased hazard of insemination, for the first service, compared with cows in Cyc49 [hazard ratio (HR) = 1.40; 95% CI = 1.10–1.79; p = 0.006] and NotCyc (HR = 2.07; 95% CI = 1.52–2.82; p < 0.001). Cows in the Cyc49 group also had increased hazard of insemination compared with cows in the NotCyc group (HR = 1.47; 95% CI = 1.13–1.93; p = 0.005). Median days to insemination were, respectively, 71, 76 and 96 for cows in Cyc21, Cyc49 and NotCyc groups. Cows in Cyc21 had greater first service pregnancy per AI than Cyc49 [38.6 vs 28.1%; adjusted odds ratio (AOR) = 1.67; 95% CI = 1.01–2.75; p = 0.04] and NotCyc (38.6 vs 23.6%; AOR = 2.08; 95% CI = 1.08–4.00; p = 0.03). Pregnancy per AI was similar in Cyc49 and NotCyc cows (28.1 vs 23.6%; AOR = 1.25; 95% CI = 0.70–2.24; p = 0.45). Cows in Cyc21 had increased hazard of pregnancy up to 300 DIM compared with Cyc49 (HR = 1.52; 95% CI = 1.17–1.96; p = 0.002) and NotCyc (HR = 1.98; 95% CI = 1.41–2.78; p < 0.001). Cows in Cyc49 tended to have increased hazard of pregnancy compared with NotCyc (HR = 1.31; 95% CI = 0.96–1.77; p = 0.09). Median days to pregnancy were, respectively, 103, 147 and 173 for cows in Cyc21, Cyc49 and NotCyc groups. Cows in the Cyc21 group had decreased prevalence of subclinical endometritis compared with cows in the NotCyc group (29.9 vs 43.7%; AOR = 0.53; 95% CI = 0.29–0.97; p = 0.04); however, the prevalence did not differ from the Cyc49 group (29.9 vs 39.1%; AOR = 0.68; 95% CI = 0.41–1.14; p = 0.15). Cyc49 cows had similar prevalence of subclinical endometritis compared with NotCyc cows (AOR = 0.77; 95% CI = 0.46–1.29; p = 0.32). Early postpartum ovulation was associated with improved uterine health and fertility.  相似文献   

Comparative efficacies of closantel,ivermectin, oxfendazole,thiophanate and levamisole against thiabendazole resistantHaemonchus contortus in sheep     

R. M. Waruiru  E. H. Weda  R. O. Otieno  J. W. Ngotho  H. O. Bøgh 《Tropical animal health and production》1996,28(3):216-220

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The relation between biomass yield and linear measures of growth in Sesbania sesban in western Kenya     

K. Otieno  J. F. M. Onim  M. J. Bryant  B. H. Dzowela 《Agroforestry Systems》1991,13(2):131-141

Various linear measurements were made on 115 provenances of Sesbania sesban var. nubica to establish their relationships with woody and leafy biomass yields of the trees after a year's undisturbed growth. Data were subjected to simple and multiple linear regression analyses. There were significant (P < 0.001) correlations in most cases but particularly so with leafy and total biomass where over 50% of the variations were accounted for by their regression on stem diameter at knee height (DKH). When data for dependent variables were logarithmically transformed, better regression coefficients (over 60%) were obtained for stem diameter at breast height (DBH) and DKH.  相似文献   

Soil fertility changes and response of maize and beans to green manures of leucaena,sesbania and pigeonpea     

J. F. M. Onim  M. Mathuva  K. Otieno  H. A. Fitzhugh 《Agroforestry Systems》1990,12(2):197-215

Three multipurpose tree species (MPTS)-leucaena (Leucaena leucocephala), sesbania (Sesbania sesban var. nubica) and pigeonpea (Cajanus cajan) were pruned at a height of 60 cm above the ground every two months, and resulting plant biomass was incorporated into the soil as green manure. For comparison, maize (Zea mays) stover was also incorporated into some plots, while some other plots were left fallow. Varying quantities of plant biomass which were incorporated into the soil over a period of 12 months caused large changes in major soil plant nutrients, and it substantially improved soil fertility. To test for improved soil fertility, test crops of maize and beans (Phaseolus vulgaris) were grown on the plots after six biomass incorporations of 4806, 13603, 16659 and 7793 kg. ha^–1yr^–1 for pigeonpea, sesbania leucaena and maize, respectively. Responses of the test crops indicated that sesbania and leucaena green manures improved maize stover, cobs and grain yields; and bean haulms and grain yields by 77.6% when compared to fallow plots. Residual effects of green manures still resulted in significant (P < 0.05) yield differences in the test cropin the third testing season. Economic significance of green manures in increasing food crop yields to small scale farmers is discussed.  相似文献   

Characterization of Indigenous Fat-tailed and Fat-rumped Hair Sheep in Kenya: Diversity in Blood Proteins     

Mwacharo JM  Otieno CJ  Okeyo AM  Aman RA 《Tropical animal health and production》2002,34(6):515-524

This paper reports the variation in five blood proteins from five populations of sheep found in Kenya. Blood samples were collected from a total of 309 adult sheep of both sexes in Kwale, Makueni and Kakamega districts for the fat-tailed sheep and in Isiolo district for the fat-rumped hair sheep. Fine-wooled Merino sheep were used in this study as the reference population. Transferrin, esterase-A and esterase-C were polymorphic in all the populations investigated, while albumin was monomorphic for the S allele in the fat-tailed sheep and haemoglobin was fixed for the B allele in the Kwale, Makueni and Isiolo populations. Phylogenies derived from the pairwise genetic distance estimates showed a clear separation between the indigenous sheep populations and the exotic Merino. However, the topology of the former showed rather poor consistency with their morphological classification based on the localization of their fat deposits, namely fat-tailed or fat-rumped hair sheep.  相似文献   

根系限制对番茄幼苗生长、根系呼吸、ATPase和PPase活性的影响   总被引：1，自引：0，他引：1  

师恺  胡文海  董德坤  宋兴舜  夏晓剑  周艳虹  喻景权 《园艺学报》2006,33(4):853-855

 采用营养液水培的方式, 研究了根系限制处理对番茄幼苗生长、根系呼吸、质膜和液泡膜上相关酶以及根尖细胞超微结构的影响。结果表明, 在处理初期, 根系限制促进了番茄幼苗根系细胞色素途径呼吸而抑制了交替途径呼吸; 而在后期, 根系限制处理显著地抑制了番茄植株的生长, 对根系的生长抑制更为明显, 且抑制过程伴随着根系总呼吸、细胞色素途径呼吸的降低。此外, 根系限制显著抑制了质膜H⁺ -ATPase, 液泡膜H⁺-ATPase和H⁺ -PPase的活性并导致根尖细胞核的解体。  相似文献   

Therapy trial using betamethasone in addition to specific treatment with a diamidine and quinuronium derivate in cattle experimentally infected with Babesia bigemina.     

F K L?hr  P S Otieno  W Gacanga 《Bulletin of animal health and production in Africa》1976,24(2):199-205

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Sexual Precocity of Nellore Bulls that are Offspring of Super Precocious,Precocious and Normal Cows in Extensive Farming Conditions     

JB Siqueira  E Oba  RO Pinho  SEF Guimarães  TM Neto  JD Guimarães 《Reproduction in domestic animals》2014,49(5):851-857

The objective of this work was to verify that mothers classified as super precocious (M1) and precocious (M2) produce more precocious bulls than females classified as normal (M3). This study included 21 186 animals with an average age of 21.29 ± 1.77 months that underwent a breeding soundness evaluation from 1999 to 2008. Of these animals, 2019, 6059 and 13 108 were offspring of M1, M2 and M3 females, respectively. In the breeding soundness examination, the animals were classified as sound for reproduction, sound under a natural mating regime, unsound for reproduction and discarded. To compare the averages obtained for each category of mother within the individual breeding soundness classes, a chi‐square test with a 5% error probability was used, considering the effects of year and month of birth and farm. For the three classes of mothers (M1, M2 and M3), 67.26, 67.22 and 64.16% of bull calves were considered sound for reproduction and 19.71, 19.46 and 21.90% were considered unsound for reproduction, respectively. There was no difference in the frequency of animals that were sound for reproduction under the natural breeding regime between the three classes of mothers (8.87, 9.31 and 9.19%, respectively). There was a difference between the numbers of precocious and normal females that were discarded, with frequencies of 4.01 and 4.75%, respectively (p < 0.05). There were differences in year and month of birth and farm between super precocious and precocious cows in relation to the breeding soundness classification of the animals. It was concluded that the bull offspring of super precocious and precocious cows presented a higher percentage of approval in the breeding soundness examination than the bull offspring of normal cows, demonstrating that the selection for precocity of females has contributed to an increase in the sexual precocity of the herd in relation to the sexual maturity of bulls.  相似文献   

Local management and landscape drivers of pollination and biological control services in a Kenyan agro-ecosystem     

Mark Otieno  Ben A. Woodcock  Andrew Wilby  Ioannis N. Vogiatzakis  Alice L. Mauchline  Mary W. Gikungu  Simon G. Potts 《Biological conservation》2011,(10):2424-2431

Arthropods that have a direct impact on crop production (i.e. pests, natural enemies and pollinators) can be influenced by both local farm management and the context within which the fields occur in the wider landscape. However, the contributions and spatial scales at which these drivers operate and interact are not fully understood, particularly in the developing world. The impact of both local management and landscape context on insect pollinators and natural enemy communities and on their capacity to deliver related ecosystem services to an economically important tropical crop, pigeonpea was investigated. The study was conducted in nine paired farms across a gradient of increasing distance to semi-native vegetation in Kibwezi, Kenya. Results show that proximity of fields to semi-native habitats negatively affected pollinator and chewing insect abundance. Within fields, pesticide use was a key negative predictor of pollinator, pest and foliar active predator abundance. On the contrary, fertilizer application significantly enhanced pollinator and both chewing and sucking insect pest abundance. At a 1 km spatial scale of fields, there were significant negative effects of the number of semi-native habitat patches within fields dominated by mass flowering pigeonpea on pollinators abundance. For service provision, a significant decline in fruit set when insects were excluded from flowers was recorded. This study reveals the interconnections of pollinators, predators and pests with pigeonpea crop. For sustainable yields and to conserve high densities of both pollinators and predators of pests within pigeonpea landscapes, it is crucial to target the adoption of less disruptive farm management practices such as reducing pesticide and fertilizer inputs.  相似文献   

Risk factors for rotavirus infection in pigs in Busia and Teso subcounties,Western Kenya     

J. O. Amimo  T. F. Otieno  E. Okoth  J. O. Onono  B. Bett 《Tropical animal health and production》2017,49(1):105-112

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