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1.
We have identified the feed offered to native pigs in a case study of smallholder in northern Thailand. We examined the types and fresh weights of pig feed over two 10-day periods in household A, in September 2006 (rainy season) and in December 2006 and January 2007 (dry season). The study results are as follows. (1) They offered 18 types of feed in total during the rainy and dry seasons, of which seven types were common to the rainy and dry seasons, five types were offered during the rainy season only, and six types during the dry season only. (2) They offered agricultural products as 34% of feed (rainy season) and 61% of feed (dry season), and natural plants used exclusively for pig feed as 66% of feed (rainy season) and 39% of feed (dry season). (3) The feed combinations at each feeding time differed 80% of the time during both the rainy and dry seasons. These results show not only that they offered diverse combinations of agricultural products and natural plants as pig feed, but also that they changed feed kinds in both the rainy and dry seasons.  相似文献   

2.
喀斯特生境中野猪活动模式和时间分配   总被引：1，自引：0，他引：1  
2017年1月—2017年12月在弄岗国家级自然保护区布设119台红外相机,通过对红外相机拍摄的野猪(Sus scrofa)的行为活动进行分析,并采用核密度估计(kernel density estimation)、重叠指数(coefficient of overlap)和相对活动强度指数(relative activity intensity index)研究野猪的活动模式和时间分配,以探讨其对喀斯特生境的适应策略。结果表明:野猪的日活动模式呈单峰型,活动峰值出现在16:00—18:00,属于典型的昼行性动物。旱雨季间野猪的日活动重叠指数存在极显著差异(Δ=0.82,P<0.01),旱季上午的活动峰值比雨季提前1 h出现。野猪的日活动主要以觅食(64.6%)和移动(25.1%)为主。不同月份间野猪的相对活动强度指数存在极显著差异(t=9.626,df=11,P<0.01),但旱、雨季间不存在显著差异(Z=-0.321,P=0.748)。旱季野猪的活动时间(17.89±1.70 s)略长于雨季(17.12±1.95 s)。本研究初步掌握了弄岗保护区内的野猪活动模式和时间分配,为后期进一步研究其栖息地选择、种群保护及环境变化对其行为的影响等提供基础数据参考。  相似文献   

3.
The interferon-tau (IFN-tau) secretion levels after hatching by bovine blastocysts derived from in vitro maturated oocytes (Group A) and from in vivo (Group B) were investigated considering embryo quality. Only very homogeneous blastocysts of excellent or good quality were considered from day 7 of culture (Group A) and day 7 after artificial insemination with frozen-thawed from the same bull used for in vitro fertilization (Group B). All embryos were individually cultured into a 50 microl droplet of synthetic oviduct fluid medium with 10% fetal calf serum. After 24-h culture both Group A (n=44) and B (n=40) secreted <54 pm IFN-tau. After 48-, 72-, 96- and 120-h culture, Group A daily secreted 143 +/- 24 pm IFN-tau (n=19) vs 85 +/- 12 pm IFN-tau (n=21) for Group B (p < 0.01), 491 +/- 128 pm IFN-tau (n=29) vs 216 +/- 37 pm IFN-tau (n=23) (NS), 499 +/- 135 pm IFN-tau (n=26) vs 353 +/- 93 pm IFN-tau (n=21) (NS), 559 +/- 136 pm IFN-tau (n=22) vs 333 +/- 75 pm IFN-tau (n=20) (NS), respectively. Taken all together during 5 days, Group A produced per embryo 1690 +/- 290 pm IFN-tau (n=22) vs 982 +/- 182 pm IFN-tau (n=20) for Group B (p < 0.05). For all culture time there were sizable percentages of embryos that did not produce concentrations of IFN-tau above a certain cut-off level, and as such were not used to compute the means. In respect of the embryo quality whatever the groups after days 7-12 of culture, IFN-tau secretions were 1815 +/- 453 pm (n=10) for the embryos of excellent quality vs 1356 +/- 200 pm (n=28) for those of good quality (NS) and 360 +/- 188 pm (n=4) (p < 0.05) for embryos of fair quality. A positive relationship between IFN-tau production and in vitro development of quality I embryos was observed, whatever the embryos origins and, the embryos completely produced in vitro secreted more IFN-tau than the embryos produced in vivo.  相似文献   

4.
Of 1346 faecal samples from the Chikwawa and Thyolo districts of Malawi, analysed for the presence of Cryptosporidium oocysts between October 2001 and May 2003, 61.3% were from cattle (29.8% of these were from calves <6 months old). Cryptosporidium oocysts were detected during all three seasons studied in Chikwawa and Thyolo. In Chikwawa, 13.6% of adult cattle and 11.7% of calves were infected, compared to 28.9% of adult cattle and 36.7% of calves in Thyolo. Dependent on season, between 7.8% and 37.7% (Chikwawa) and 16.7% and 39.3% (Thyolo) of cattle samples contained oocysts. In Chikwawa, the highest percentage of infections occurred in the cool season, whereas in Thyolo, the highest percentage of infections occurred in the dry season. Faecal samples from goats [n=225], pigs [n=92], sheep [n=6]), rabbits, guinea pigs, chickens, ducks, turkeys, doves and guinea fowls were also analysed. Up to 5.6% of goat samples contained oocysts in Chikwawa, compared to between 16.7% and 39.3% in Thyolo. Again, in Chikwawa, the highest percentage of infections occurred in the cool season and the lowest in the rainy season, whereas, in Thyolo, the highest percentage of infections occurred in the dry season and the lowest in the cool season. In pigs, more infections were detected in the dry season in Chikwawa, but infections in the cool season were similar (17.7%), whereas in Thyolo, infections occurred in all three seasons (17.9% in the rainy season, 25% in the cool season and 60% in the dry season). Of ten diarrhoeic, oocyst positive cattle faecal samples collected from Chikwawa and subjected to PCR-RFLP, four oocyst positive samples (two from heifers, one from a cow and one unknown) were amplified at an 18S rRNA and Cryptosporidium oocyst wall protein (COWP) loci. RFLP of the 18S rRNA locus indicated that Cryptosporidium parvum, Cryptosporidium hominis, Cryptosporidium bovis and/or Cryptosporidium ryanae DNA, or a mixture of them was present. Cryptosporidium parvum DNA was identified in one sample that amplified at the COWP locus, indicating the presence of the major zoonotic Cryptosporidium species in Malawi.  相似文献   

5.
The ovarian activities of 7 jennies were studied by serial ultrasonography during seasons of higher and lower sexual activity to determine if follicular development also corresponds to this pattern. The current study showed a seasonal pattern of ovarian activities related to the local environmental factors associated with each season rather than photoperiod, which is the widely known environmental cue determining seasonality in most equines. Jennies produced large numbers of follicles (11.3 follicles) during the long rainy season, compared with the 7.3 and 9.6 follicles during the dry and short rainy seasons, respectively. However, production of larger preovulatory follicles (37.8 ± 1.7 mm vs 31.0 ± 2.7 mm of the dry and 33.2 ± 2.7 mm of the long rainy seasons) and higher incidence of ovulation (77.8%) occurred during the short rainy season. Jennies had shorter interovulatory intervals during the season of higher (short rainy) than the season of lower (dry season) sexual activity. The short rain transition is characterized by higher follicular activity compared with the long rainy transition, indicating the presence of additional factors stimulating ovarian activity other than the mere availability of forage during the short rainy season.  相似文献   

6.
1. An experiment was carried out with 120 helmeted guinea fowls during one year in Parakou (Benin). Feed intake, ingredient and chemical composition, along with the nutritional adequacy of scavenging diets were measured during the rainy season (November–February) and dry season (March–October) in order to propose supplementation strategies. Ingredients found in crops were identified and allocated into 6 main categories (supplemental feed, seeds, green forages, animal materials, mineral matter and unidentified materials).

2. Mean dry weights of crop contents were significantly higher in the rainy than in the dry season. Amounts and proportions of supplemental feed and seeds were not significantly different between seasons, whereas those of green forage, animal materials and mineral matter were higher in rainy season. Supplemental feed, especially maize and sorghum, was the largest component of the crop content in both seasons. The most represented grass seeds were Panicum maximum (rainy season) and Rottboellia cochinchinensis (dry season).

3. Dietary concentrations of organic matter, non-nitrogen extract and metabolisable energy were higher in the dry season, while mineral concentrations were higher in the rainy season. There were no significant differences between the two seasons in dry matter, crude protein or crude fibre.

4. Scavenging provided insufficient nutrients and energy to allow guinea fowls to be productive. Therefore, more nutritionally balanced supplementary feed would be required during both seasons.  相似文献   


7.
The study investigated seasonal changes in the morphology of the seminal vesicles of Eidolon helvum in a typical African tropical environment. Seminal vesicles of forty-eight bats were examined during the early rainy, late rainy and peak dry seasons, using gross anatomical, histological and ultrastructural techniques. The interlobular connective tissue septa from the external capsule demarcated the glandular parenchyma into numerous lobules of tubulo-alveolar glands. A simple cuboidal epithelium of mono- or bi-nucleated cuboidal cells lined the glandular mucosa during the rainy season. This was replaced by a bistratified cuboidal epithelium, whose upper layer of cells showed evidence of degeneration, during the dry season. The PAS-positive secretory products appeared to be numerous during the rainy season, but few and clumped together during the dry season. The mean gross weight, interlobular septal thickness, acini diameter and epithelial height of the glands varied significantly with season. Ultrastructural features of the secretory cells during the rainy season showed well-developed cytoplasmic organelles, numerous electron lucid secretory vesicles and electron-dense granules. Secretory epithelial cells of the seminal vesicles are very active during the rainy season, while regeneration of degenerated epithelium in preparation for the next reproductive cycle occurs during the dry season.  相似文献   

8.
Forty sows comprising equal numbers of Landrace (LR) and Large White (LW) breeds were studied for 20 months to determine the effects of dry and rainy seasons on their fertility traits in Nigeria. Ambient temperature (14.0-35.5 degrees C) was lowest at night and highest in the day and peaked during the dry season. A relative humidity range of 60-82% peaked during the late rainy season. LR produced 218 and 278 piglets from 23 and 28 litters, while LW produced 193 and 316 piglets from 20 and 30 litters during dry and rainy seasons respectively. Fertility traits did not differ significantly between the breeds due to season (P greater than 0.05). Mean post-weaning oestrus at 10.9 and 9.0 days and preweaning mortality rates of 14.2% and 16.9% during dry and rainy seasons for LR differed significantly (P less than 0.5) from those of LW which were 12.2 and 8.2 days and 14.5% and 18.9% respectively. The significance of seasonal effects on sow fertility and necessary management techniques are discussed.  相似文献   

9.
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10.
Ostriches are susceptible to a wide variety of diseases that can affect their commercial breeding. The aim of this study was to identify morphologically Codiostomum struthionis and examine its seasonal occurrence among animals of three age categories in two commercial farms in Areal and Itaboraí, State of Rio de Janeiro, Brazil. Fresh fecal samples were collected monthly, from June 2004 to May 2006. Eggs per gram of feces (EPG) were counted after centrifugal flotation in saturated sugar solutions and infective larvae were evaluated after coproculture. A total of 432 fecal samples were collected from three groups according to ostrich age: up to 90 days, 91-365 days and over 365 days (adults). The dry and rainy seasons were defined according to official meteorological data. Typical eggs of the Strongylida order were identified in 242 samples (235 from adult ostriches). Once obtained, infective larvae were identified as C. struthionis. Adult ostriches exhibited significantly greater numbers of eggs in their feces during the rainy season compared to the dry season (p<0.05). In the Areal farm, significant (p<0.05) values were found when adults ostriches EPG were compared to ostriches up to 90 days and also for ostriches from 91 to 365 days. When comparing adult EPGs between the two commercial breeding farms, Areal exhibited greater EPGs during both the dry (p=0.0215) and rainy (p=0.0011) seasons.  相似文献   

11.

Nitrogen (N) plays an important role in small-scale dairy systems, both in production costs and as an indicator of environmental impact. The objective of this study was to quantify nitrogen inputs and outputs to identify areas for improvement in nitrogen utilisation efficiency (NUE). Evaluation was in 12 small-scale dairy farms with different feeding strategies. Six followed the traditional cut and carry of irrigated temperate pastures (CUT), and six have implemented grazing of pastures (GRZ), quantifying N inputs and outputs from May 2016 to April 2017. Data were analysed by ANOVA following a split-plot model with season (rainy or dry) as main plots and feeding strategy (CUT or GRZ) as split-plots, with results in kilograms N per hectare and kilograms N per cow. There were differences (P < 0.05) between seasons and strategies in N inputs from purchased N fertilisers and purchased feeds as concentrates and roughages, showing different N inputs and outputs whether in CUT or GRZ strategies. There were also significant interactions between seasons and strategies as in the sale of animals, where GRZ sell throughout the year, while CUT sell at the beginning of the dry season. N balance ranged from 33.9 to 183.0 kg N/ha, and 37.8 to 111.0 as kilograms N per cow with an interaction (P < 0.05) between season and strategies. There was a larger N surplus in GRZ during the rainy season from fertiliser inputs, which reduced N utilisation efficiency (NUE). Mean NUE in kilograms N per hectare and kilograms N per cow was 19%, with the higher efficiency for GRZ in the dry season. Farms with the best NUE had lower use of fertilisers and purchased feeds.

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12.
Three experimental approaches were used to study transmission of blue tongue (BT), infectious bovine rhinotracheitis (IBR) and bovine virus diarrhoea (BVD) viruses. These were insemination with contaminated semen, experimental infection of embryo donor cows, or transfer of embryos experimentally exposed to virus in vitro to normal recipients. Parameters assessed included number and quality of embryos produced, virus detection (isolation and electron microscopy), serology and histopathology. All superovulated sesceptible cows inseminated with semen containing blue tongue virus (BTV) (n = 2) or infectious bovine rhinotracheitis virus (IBRV) (n = 2) became infected. One cow inseminated with semen containing BTV produced seven virus-free seven-day-old embryos; the second cow failed to produce any embryos. One of two cows inseminated with semen containing IBRV produced two underdeveloped, virus-free embryos while no embryos were produced by the second cow. One of two cows inseminated with semen containing bovine viral diarrhoea virus (BVDV) became infected. Two poorly developed, virus-free seven-day-old embryos were recovered from one of these cows. Superovulated susceptible cows inoculated either intramuscularly with BTV (n = 3) or intranasally with IBR virus (n = 2) became infected. Virus was isolated from some tissues of two BTV-infected cows, neither of which produced embryos. A third BTV-infected cow produced two virus-free embryos collected at necropsy five days after inoculation. One of two cows experimentally infected with IBR virus, produced three embryos but virus was not detected either by electron microscopy (1 embryo) or in cell culture by cytopathic alterations (1 embryo).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

13.
Nutritive value of selected grasses in North Sumatra, Indonesia   总被引：1，自引：0，他引：1  
The nutritive values of seven native grass species collected in North Sumatra, Indonesia, during dry and rainy seasons were evaluated. The chemical composition, in vitro dry matter digestibility (IVDMD), in vitro organic matter digestibility (IVOMD), in vitro crude protein digestibility (IVCPD), macro mineral concentrations of calcium, phosphorus and magnesium, in vitro gas production profile and metabolizable energy (ME) content of the grasses varied greatly among species and seasons. The crude protein content ranged from 6.6 (Andropogon gayanus) to 16.2% dry matter (Cynodon plectostachyus) in the rainy season, with a significant (P < 0.05) reduction in the dry season. Data on the fiber fraction showed that the grasses contained more neutral detergent fiber (NDF) and acid detergent fiber (ADF) in the dry season and it significantly (P < 0.05) decreased in the rainy season, except for Panicum maximum and Pennisetum purpureum for NDF content and C. plectostachyus, P. maximum and Brachiaria decumbens for ADF content. Data on the mineral concentration showed that C. plectostachyus in the dry and rainy seasons had a higher calcium content than those of other species. The overall means of the seven grasses for IVDMD, IVOMD and IVCPD were significantly higher (P < 0.05) in the rainy season than in the dry season. The in vitro gas production and ME concentration were numerically higher in the rainy season than in the dry season. In conclusion, the nutritive value of the observed grasses in North Sumatra was relatively higher during the rainy season compared with the dry season. Among the species of grass, P. purpureum and C. plectostachyus had a higher nutritive value in both the dry and rainy seasons.  相似文献   

14.
The aim of the study was to assess the effects of superovulatory treatment (multiple FSH‐dose vs single‐shot FSH treatment) and seasonality on embryo yields in fine‐wool Merino ewes. Treatment based on multiple FSH‐dose consisted of 200 mg of FSH (Folltropin®) administered in seven decreasing doses. Single‐shot treatment consisted of a single dose of 70 mg of FSH + eCG. In ewes treated with multiple FSH doses, number of recovered embryos was higher (6.0 ± 0.5 vs 3.5 ± 1.0), while non‐fertilization rate was lower (12.8 ± 3.9 vs 40.3 ± 9.5) during the breeding season when compared to the non‐breeding season (p < 0.05); although similar values of recovered Grades 1–2 embryos were observed between seasons. During the breeding season, proportion of responding ewes (98.1 vs 57.1%), ovulation rate (13.9 ± 0.8 vs 3.2 ± 1.2), recovered structures (7.9 ± 0.6 vs 1.7 ± 0.7), total recovered embryos (6.0 ± 0.5 vs 1.2 ± 0.6) and good‐quality embryos (5.1 ± 0.5 vs 0.9 ± 0.6) were higher for the multiple FSH‐dose treatment than for the single‐shot protocol. In a similar way, in the non‐breeding season, ovulation rate (11.3 ± 1.8 vs 6.0 ± 1.1) and recovered structures (6.6 ± 1.2 vs 2.7 ± 0.6) were higher for the multiple FSH injections protocol than those for the single‐shot treatment, resulting in higher recovered Grades 1–2 embryos (3.2 ± 0.9 vs 1.4 ± 0.5). Current results indicate that seasonal anestrus affected embryo yields when applying multiple FSH‐dose superovulatory treatment in Merino ewes, by decreasing the number of recovered embryos although the number of recovered good‐quality embryos was not affected. During both seasons, multiple FSH injections produced higher ovarian response and number of viable embryos than the single‐shot treatment.  相似文献   

15.
The aim of this study was to use culture medium (McCoy®) as a test to evaluate the classification of embryos after a primary grading using stereoscopic microscopy to further confirm whether embryos have been correctly scored by stereoscopic microscopy evaluating the level of apoptosis. Forty‐six Bos indicus embryos were collected with a non‐surgical method and evaluated with stereoscopic microscopy for scoring in three categories (good, fair and poor). Cell proliferation and apoptosis were assessed and compared between the control group (n = 14) at the onset of the experiment and in an experimental group (n = 32) after stored for 4 h in a culture medium. Embryos were processed using TUNEL and BrdU markers to determine the apoptosis and cell proliferation. Seventy‐four per cent of good quality embryos developed favourably after the 4 h of culture; 60% of fair embryos maintained their evolution, while 100% of poor quality embryos presented degenerative changes from the beginning. No statistical differences were found between the experimental and the control groups in the count of positive BrdU and apoptotic nuclei. In poor quality embryos, a higher number of apoptotic cells were found relative to good and fair embryos, both in the experimental and control groups (P < 0.05). These results suggest that the culture medium may be used for a short time as a fast, practical and non‐invasive alternative to further confirm whether embryos have been correctly scored by stereoscopic microscopy.  相似文献   

16.
This study aimed to determine the prevalence and intensity of gastrointestinal nematode infections in indigenous Zebu cattle in the lower plain (lowland zone) of the southern highlands of Tanzania. Gastrointestinal tracts were randomly purchased at the Iringa regional abattoir and at Kihesa and Ipogolo slaughter slabs in different seasons of the year. The contents of the abomasum, small intestine and large intestine were processed separately to recover the worms. The results indicated that 140 out of 144 (97.2%) of the examined animals were infected. The mean (±SE) total worm burden was 1284±183 (range 10–12 600) worms per animal and most infected animals contained more than one nematode species. The nematode species present, their prevalence and mean burden were as follows: Haemonchus placei, 84.7%, 316; H. similis, 5.6%, 1; Oesophagostomum radiatum, 79.2%, 66; Cooperia pectinata, 55.6%, 713; C. punctata, 44.4%, 157; Bunostomum phlebotomum, 5.6%, 5; Trichuris globulosa, 5.6%, 2; and Trichostrongylus colubriformis, 1.4%, 24. The burdens were mainly composed of Cooperia pectinata (55.5%), Haemonchus placei (24.6%), Cooperia punctata (12.3%) and Oesophagostomum radiatum (5.1%). The highest burdens occurred at the end of the rainy/early dry season, while the lowest burdens were found at the end of the dry/early rainy season. There was no difference in the burdens between male and female animals. Immature cattle (<3 years) had significantly higher worm burdens than mature cattle (p<0.01). A poor grade for a live animal was associated with higher worm burdens only in immature cattle and then especially during the dry season (r = 0.456, p<0.001). Anthelmintic treatments in the late rainy/early dry season and early rainy season are recommended in order to prevent outbreaks of helminthosis during the dry season and to reduce carryover of infection into the next rainy season. An additional wet season treatment is advisable in immature cattle, but may not be needed for mature cattle owing to the availability of plenty of mature, good quality pasture.  相似文献   

17.
This study aimed at investigating the effect of the seasonal decline in quality and availability of feed on rumen function in sheep grazing without supplementation. Effects of season on rumen pH, ammonia nitrogen concentration and rumen degradation of urea-treated rice straw in grazing sheep were determined. Four fistulated Djallonké sheep were added to a group of grazing sheep and used for this study. Rumen contents were sampled for pH and ammonia in the rainy season and in the dry season. Ammoniated rice straw was incubated in the rumen to determine its degradation characteristics. Rumen pH was higher (p?p?>?0.05) in the two seasons. In sacco dry matter degradation parameters of urea-ammoniated rice straw showed seasonal differences in the soluble (a) and the insoluble but degradable (b) fractions as well as lag time before the start of degradation. It was concluded that despite higher pH in the dry season and similar ammonia nitrogen concentration in the two seasons, rumen degradability of dry matter of urea-treated rice straw in sheep was higher in the rainy season than that in the dry season.  相似文献   

18.
Extensive range livestock production systems in the western United States rely heavily on rangeland forages to meet the nutritional needs of grazing livestock throughout the year. Interannual variation in the quantity and quality of rangeland forage in the Northern Great Plains, as well as throughout much of the western United States, may play a pivotal role in how well grazing ruminants sequester nutrients in their tissues. This variation in forage quality may influence the ability of a beef cow to utilize dietary nutrients via changes in tissue responsiveness to insulin. Identifying specific periods and production states in which this phenomenon is manifested will provide insight into the development and implementation of strategic and targeted supplementation practices that improve nutrient utilization during times of nutritional imbalance and may improve the lifetime productivity of grazing range beef cows. A 2-yr study was conducted to monitor serum metabolites, glucose kinetics during glucose tolerance tests, and forage chemical composition every 90 d in young cows (2 to 4 yr of age; n = 28). In yr 1 and 2, cows were managed on 4 pastures varying in size from 36 to 76 ha in yr 1 and 49 to 78 ha in yr 2. Regardless of year, cow age, or cow physiological status, the main factor influencing glucose half-life was season of the year (P = 0.02). Effects of season on glucose half-life closely followed assessments describing forage quality, with glucose half-lives of 46, 39, 43, and 51 +/- 3.9 min for May, August, December, and March, respectively. Elevated glucose half-life during seasons in which forage quality is of lower nutritive value indicated that tissue responsiveness to the actions of insulin followed seasonal changes in forage quality. Glucose half-life tended (P = 0.09) to decrease between May and August, increased (P = 0.04) between December and March, and showed a tendency (P = 0.10) to decrease in seasons of greater nutrient density (May and August) compared with seasons of lower nutrient density (December and March). Seasonal changes in serum metabolites were also observed and corresponded with changes in forage quality. The results support our hypothesis that as the season progresses and forage quality declines, maternal tissues become less responsive to insulin, indicating that targeted supplementation with glucogenic precursors during these seasons of nutritional stress may improve cow performance.  相似文献   

19.
This paper reports on the effect of strategic anthelmintic treatments and other determinants on faecal egg counts (FEC) of Trichostrongyles in N'Dama cattle of a west African village. Initially, 527 animals from 13 private N'Dama cattle herds were monitored in a longitudinal study from October 1989 to December 1994. Each herd was stratified by age and animals were sequentially allocated to two groups with similar age distributions. One group received a single anthelmintic treatment of fenbendazole (7.5 mg/kg BW), in October 1989 (n = 250), whereas the other group remained untreated (n = 277) throughout the study. In the next rainy season (June to October), the treated animals were treated twice (in July and September). The same treatment schedule was used in the subsequent rainy seasons until December 1994. Biannual anthelmintic treatments decreased the level of FEC between 31% (late dry season) and 57% (rainy season), when compared to untreated controls. The highest levels of FEC were found during the rainy season from June to October. FEC levels decreased until 4 years of age, after which they remained on a constant low level. The variability of returns to anthelmintic treatments between herds did not seem to be influenced by FEC at the herd level. The financial evaluation of anthelmintic interventions cannot be predicted from FEC and must necessarily rely on the direct monitoring of livestock productivity parameters.  相似文献   

20.
Serial ultrasonography was performed on seven jennies to study the effect of seasonally fluctuating body condition on ovarian activity during the dry, short rainy and long rainy seasons. Kendall Tau correlations and differences of least square mean values were compared. A distinct seasonal pattern was observed both in body condition and ovarian activity. The mean (+/-SD) Body Condition Score (BCS) was lowest during the dry season 2.6 +/- 0.45 when compared with 3.5 +/- 0.52 and 3.9 +/- 0.58 during the short and long rainy seasons, respectively. The mean (+/-SD) number of total follicles was also proportionally low 7.3 +/- 1.6 during the dry season compared with 9.6 +/- 2.4 and 11.3 +/- 3.3 found during the short and the long rainy seasons, respectively. The BCS was positively correlated to the total number of follicles and the diameter of the largest follicle during all seasons. Periods of increasing BCS and transition between seasons with both increasing and decreasing body conditions were strongly correlated to the number and size of ovarian follicles. Seasonal fluctuation in the body condition was found to be the result of variation in feed resource and ovarian activity was also closely following this seasonal pattern. The improvement in body condition has generally, a positive impact on emergence of small growing follicles there by having influence on the total count of ovarian follicles.  相似文献   

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