scholarly journals Seasonal changes in the reproductive performance in local cows receiving artificial insemination in the Pursat province of Cambodia

2020 ◽  
Vol 33 (12) ◽  
pp. 1922-1929
Author(s):  
Bengthay Tep ◽  
Yasuhiro Morita ◽  
Shuichi Matsuyama ◽  
Satoshi Ohkura ◽  
Naoko Inoue ◽  
...  

Objective: The present study aimed to survey seasonal changes in reproductive performance of local cows receiving artificial insemination (AI) in the Pursat province of Cambodia, a tropical country, to investigate if ambient conditions affect the reproductive performance of cows as to better understand the major problems regarding cattle production.Methods: The number of cows receiving AI, resultant number of calving, and calving rate were analyzed for those receiving the first AI from 2016 to 2017. The year was divided into three seasons: cool/dry (from November to February), hot/dry (from March to June), and wet (from July to October), based on the maximal temperature and rainfall in Pursat, to analyze the relationship between ambient conditions and the reproductive performance of cows. Body condition scores (BCS) and feeding schemes were also analyzed in these seasons.Results: The number of cows receiving AI was significantly higher in the cool/dry season than the wet season. The number of calving and calving rate were significantly higher in cows receiving AI in the cool/dry season compared with the hot/dry and wet seasons. The cows showed higher BCSs in the cool/dry season compared to the hot/dry and wet seasons probably due to the seasonal changes in the feeding schemes: these cows grazed on wild grasses in the cool/dry season but fed with a limited amount of grasses and straw in the hot/dry and wet seasons.Conclusion: The present study suggests that the low number of cows receiving AI, low number of calving, and low calving rate could be mainly due to poor body condition as a result of the poor feeding schemes during the hot/dry and wet seasons. The improvement of body condition by the refinement of feeding schemes may contribute to an increase in the reproductive performance in cows during the hot/dry and wet seasons in Cambodia.

2021 ◽  
Vol 31 (1) ◽  
pp. 112-118
Author(s):  
L. D. Massoma ◽  
N. M. Ngo ◽  
J. Tchoumboue ◽  
O. Messono

This study was undertaken to determine the reproductive performance of the endangered Bos-taurus Namshi breed of Cameroon. Ovarian response to superovulatory treatment was also evaluated. The following observations were recorded. The average calf mortality rate was 25.71% while the average birth weight was 12.22±0.82kg. The percentage of animals in oestrus during the wet and dry season was respectively 60% and 33.4%. The oestrus cycle length and the oestrus duration were respectively 20.80±1.20d and 7.00±0.80h: corresponding dry season figures for those parameters were 19.00±0.94d and 6.00±0.7h respectively. In the dry season the manifestation of oestrus was 80º during the day and 20º at night while in the wet season it was 55.55% and 44.5% respectively. Postpartum oestrus was at 18 months. The ovarian response to superovulatory treatment was about 6.40±2.50 ovulations per cow. Results indicate that the scarcity of Bos-taurus Namshi breed in Camerron could be attributed to high calf mortality rate, low calving rate and long postpartum periods. Embryo transfer could be a way to rapidly multiply this breed.  


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Xue Zhu ◽  
Jiyue Qin ◽  
Chongyang Tan ◽  
Kang Ning

Abstract Background Most studies investigating human gut microbiome dynamics are conducted on humans living in an urban setting. However, few studies have researched the gut microbiome of the populations living traditional lifestyles. These understudied populations are arguably better subjects in answering human-gut microbiome evolution because of their lower exposure to antibiotics and higher dependence on natural resources. Hadza hunter-gatherers in Tanzania have exhibited high biodiversity and seasonal patterns in their gut microbiome composition at the family level, where some taxa disappear in one season and reappear later. Such seasonal changes have been profiled, but the nucleotide changes remain unexplored at the genome level. Thus, it is still elusive how microbial communities change with seasonal changes at the genome level. Results In this study, we performed a strain-level single nucleotide polymorphism (SNP) analysis on 40 Hadza fecal metagenome samples spanning three seasons. With more SNP presented in the wet season, eight prevalent species have significant SNP enrichment with the increasing number of SNP calling by VarScan2, among which only three species have relatively high abundances. Eighty-three genes have the most SNP distributions between the wet season and dry season. Many of these genes are derived from Ruminococcus obeum, and mainly participated in metabolic pathways including carbon metabolism, pyruvate metabolism, and glycolysis. Conclusions Eight prevalent species have significant SNP enrichments with the increasing number of SNP, among which only Eubacterium biforme, Eubacterium hallii and Ruminococcus obeum have relatively high species abundances. Many genes in the microbiomes also presented characteristic SNP distributions between the wet season and the dry season. This implies that the seasonal changes might indirectly impact the mutation patterns for specific species and functions for the gut microbiome of the population that lives in traditional lifestyles through changing the diet in wet and dry seasons, indicating the role of these variants in these species’ adaptation to the changing environment and diets.


2012 ◽  
Vol 63 (9) ◽  
pp. 788 ◽  
Author(s):  
N. E. Pettit ◽  
T. D. Jardine ◽  
S. K. Hamilton ◽  
V. Sinnamon ◽  
D. Valdez ◽  
...  

The present study indicates the critical role of hydrologic connectivity in floodplain waterholes in the wet–dry tropics of northern Australia. These waterbodies provide dry-season refugia for plants and animals, are a hotspot of productivity, and are a critical part in the subsistence economy of many remote Aboriginal communities. We examined seasonal changes in water quality and aquatic plant cover of floodplain waterholes, and related changes to variation of waterhole depth and visitation by livestock. The waterholes showed declining water quality through the dry season, which was exacerbated by more frequent cattle usage as conditions became progressively drier, which also increased turbidity and nutrient concentrations. Aquatic macrophyte biomass was highest in the early dry season, and declined as the dry season progressed. Remaining macrophytes were flushed out by the first wet-season flows, although they quickly re-establish later during the wet season. Waterholes of greater depth were more resistant to the effects of cattle disturbance, and seasonal flushing of the waterholes with wet-season flooding homogenised the water quality and increased plant cover of previously disparate waterholes. Therefore, maintaining high levels of connectivity between the river and its floodplain is vital for the persistence of these waterholes.


1989 ◽  
Vol 16 (2) ◽  
pp. 141 ◽  
Author(s):  
P Bayliss ◽  
WJ Freeland

Aerial surveys of coastal waters (27 216 km2) in the western Gulf of Carpentaria during the dry season of 1984 and wet season of 1985 indicated no major seasonal changes in distribution and relative abundance of dugongs. Minimum population size in the dry season was estimated as 16 816 � 2946 (standard error), with a relative density of 0.62 k 0.11 km-2, and that for the wet season 16 846 + 3257, with a relative density of 0.62 � 0.12 km-2. The estimates exclude 5% of observations which could have been either dugongs or Irrawaddy dolphins, and were corrected for submerged dugongs and those missed on the surface. Dugongs were unevenly distributed over the study area, and neither mean group size nor proportion of calves varied between seasons. Dugong abundance was correlated with area of available seagrass. The catch rate of dugongs by Aboriginal people off Numbulwar decreased six-fold between the 1960s and 1985 (60 to 10 p.a.), possibly due to excessive hunting.


2009 ◽  
Vol 19 (2) ◽  
pp. 418-422 ◽  
Author(s):  
Peter Juroszek ◽  
Hsing-Hua Tsai

Organic production is considered by many researchers to be a viable alternative to conventional farming systems. Equivalent yields already have been demonstrated in several studies. The major objective of our study was to collect data on total and marketable fruit yields of sweet pepper (Capsicum annuum) under organic farming conditions in the tropics. Experiments were conducted during the hot-wet season from 7 Mar. 2007 to 30 July 2007 and during the cool-dry season from 27 Nov. 2007 to 7 Apr. 2008. The six experimental entries included four commercial F1 hybrids and two genotypes bred at AVRDC–The World Vegetable Center (Shanhua, Taiwan). During the hot-wet season, high total (44.6–55.7 t·ha−1) and marketable yields (36.9–45.6 t·ha−1) were achieved under organic farming conditions in the open field similar to yields of conventionally produced sweet pepper in previous field experiments at AVRDC. The total yield of the commercial cultivars Queen Star and Hercules exceeded 50 t·ha−1; however, this was not significantly different compared with the other trial entries. During the cool-dry season, the total (25.4–45.7 t·ha−1) and marketable yields (21.1–37.8 t·ha−1) of all trial entries were reduced, probably because the relatively late planting date in November and relatively low air temperature resulted in reduced fruit set. The commercial cultivars Andalus and Green Bell Improved realized in both seasons a total fruit yield of more than 40.0 t·ha−1, suggesting that these can be grown successfully in hot-wet and cool-dry seasons. The relatively high yields of sweet pepper achieved on-station under tropical climatic conditions may encourage farmers and agricultural stakeholders to consider organic farming approaches as a viable alternative to conventional farming systems.


2011 ◽  
Vol 11 (47) ◽  
pp. 5413-5430
Author(s):  
I Amoako-Attah ◽  
◽  
RT Awuah ◽  
CM Jolly ◽  
◽  
...  

Fungi and insects infestation of groundnut kernels in storage is a serious post-harvest problem. It leads to quality deterioration and loss of market value and kernels may become contaminated with aflatoxin (AF), which has many negative health implications when consumed. Currently, botanical pesticides are highly preferred to synthetic ones during storage. Effectiveness of preserving groundnut kernels against fungi and insect damage with Syzygium aromaticum cloves (fruits) powder were assessed in the laboratory. Another experiment was conducted under farmer’s storage conditions to evaluate potential of Syzygium powder to protect kernels against AF contamination. In the laboratory assessment, 3 kg kernel samples from sun-dried and undried pods were protected with 2 % (w/w) Syzygium powder. Kernels were kept under ambient conditions in sanitised and non-sanitised rooms for six months during the dry season. Unprotected kernels were kept as control and costs of applying the treatments were estimated. The experiment was repeated in the wet season. Under farmer’s storage, 50 kg kernel lots of 6 and 9 % initial storage moisture contents were protected with 2 % (w/w) Syzygium powder. Kernel lots stored without Syzygium powder served as control. These were packaged in interlaced polypropylene bags (IPPB) or polyethylene bags (PB) and stored in a farmer’s barn on farm. In dry and wet seasons, fungi colonised all kernels stored in laboratory from undried pods completely at three months. Pod drying costs GH¢ 8.99 (GH ¢0.82 = $ US1) and it was cost effective against fungi infection in dry season. Protecting kernels with Syzygium powder was estimated at GH¢ 17.87/100 kg lot and under the humid conditions in wet season, it proved cost effective against fungi infection. However, insect damage to the kernels was always higher after three months. Insects damage and fungi colonisation of kernels packaged in either PB or IPPB were reduced significantly (P < 0.05) at three months storage under farmer’s conditions, when they were protected with Syzygium powder. Aflatoxins do not use abbreviation at beginning of sentence were not detected in the kernels prior to storage. At three months, however, Syzygium-protected kernels had AF levels ranging between 0 and 29.30 µg/kg compared to 27.5-84.0 µg/kg associated with unprotected kernels. Syzygium powder applied at 2 % (w/w) was effective against fungi colonisation, insect infestation and subsequent AF contamination of kernels in storage. However, the kernels should be stored for three months.


2014 ◽  
Vol 11 (6) ◽  
pp. 7901-7929
Author(s):  
S. A. Parsons ◽  
V. Valdez-Ramirez ◽  
R. A. Congdon ◽  
S. E. Williams

Abstract. The seasonality of litter inputs in forests has important implications for understanding ecosystem processes and biogeochemical cycles. We quantified the drivers of seasonality in litterfall and leaf decomposability, using plots throughout the Australian wet tropical region. Litter fell mostly in the summer (wet, warm) months in the region, but other peaks occurred throughout the year. Litterfall seasonality was modelled well with the level of deciduousness of the site (plots with more deciduous species had lower seasonality than evergreen plots), temperature (higher seasonality in the uplands), disturbance (lower seasonality with more early secondary species) and soil fertility (higher seasonality with higher N : P/P limitation) (SL total litterfall model 1 = deciduousness + soil N : P + early secondary sp: r2 = 0.63, n = 30 plots; model 2 = temperature + early secondary sp. + soil N : P: r2 = 0.54, n = 30; SL leaf = temperature + early secondary sp. + rainfall seasonality: r2 = 0.39, n = 30). Leaf litter decomposability was lower in the dry season than in the wet season, driven by higher phenolic concentrations in the dry, with the difference exacerbated particularly by lower dry season moisture. Our results are contrary to the global trend for tropical rainforests; in that seasonality of litterfall inputs were generally higher in wetter, cooler, evergreen forests, compared to generally drier, warmer, semi-deciduous sites that had more uniform monthly inputs. We consider this due to more diverse litter shedding patterns in semi-deciduous and raingreen rainforest sites, and an important consideration for ecosystem modellers. Seasonal changes in litter quality are likely to have impacts on decomposition and biogeochemical cycles in these forests due to the litter that falls in the dry being more recalcitrant to decay.


Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1806 ◽  
Author(s):  
Feng-Hsin Hsu ◽  
Chih-Chieh Su ◽  
Pei-Ling Wang ◽  
In-Tian Lin

Submarine groundwater discharge (SGD) is evidenced around Taiwan, but the seasonal/temporal changes of SGD have not been fully examined. Here, we report a time-series investigation of SGD into a tide-dominated coastal wetland, the Gaomei Wetland, located to the south of the Da-Chia River’s mouth, western Taiwan, by using environmental tracers (222Rn, 224Raex, 228Ra, δD, and δ18O). Our results showed that regardless of dry and wet seasons, the 222Rn activities in coastal waters were high at low tide but low at high tide. It represents the continuous input of 222Rn-enriched groundwater. However, the 224Raex and 228Ra activities showed seasonal changes with tide conditions. In the dry season, the 224Raex and 228Ra activities in coastal waters were low at low tide but high at high tide; whereas in the wet season, an opposite relation was observed with quite high 224Raex and 228Ra activities in the low-tide waters. Coupled with the lower δD and δ18O values of coastal and pore waters in the dry season, in comparison to those in the wet season, it is suggested that these phenomena probably reflected a seasonal difference in the main SGD component with fresh SGD in the dry season, but saline ones in the wet season. Based on a 222Rn mass balance model, the estimated SGD fluxes into the Gaomei Wetland varied with tidal fluctuations and ranged from 0.2 to 25 cm d−1 and from 0.1 to 47 cm d−1 for the dry and wet seasons, respectively. A slightly high SGD flux occurring during the wet season at spring tide, implied a stronger tidal pumping coupled with a larger hydraulic gradient between land and sea. In this study, we demonstrated that the variation of SGD into the Gaomei Wetland is not only controlled by the seasonal changes of groundwater recharge, but also by the tidal pumping process.


2004 ◽  
Vol 44 (8) ◽  
pp. 755
Author(s):  
G. Bortolussi ◽  
A. R. Bird ◽  
C. L. Playford ◽  
J. Moore

Ninety young Merino ewes, depastured on Mitchell (Astrebla spp.) grass pastures in North West Queensland, were used in a hormonal growth promotant implantation study. The ewes were given 1 implant of Compudose, Ralgro, Revalor or Synovex-H, either at lamb marking (mid-dry season) or the start of the following summer wet season, which was ~180 days post-marking. The hormonal growth promotant implanted groups had greater (P<0.05) liveweights than the control group early in the trial (days 22 and 57) and also from the end of the period of activity of the wet season implant (day 277) until the middle of the dry season (day 412). Dry season (at lamb marking) implantation did not improve average daily gain. From the end of the wet season onwards, ewes with a wet season implant were heavier (P<0.05) than those ewes implanted at lamb marking. This liveweight advantage had diminished by the start of the autumn mating. Hormonal growth promotant implantation had a favourable (P<0.05) effect on growth rate, but adversely affected reproduction in the ewes, regardless of time of implantation. Implantation with Compudose or Synovex-H significantly (P<0.001) reduced the demonstration of oestrus, while Revalor or Synovex-H reduced pregnancy rates by up to 100%. Despite Ralgro reducing these variables by up to 25%, its effect was not significant. All ewes that were diagnosed as pregnant at 140 days later produced lambs. It was concluded from this study that hormonal growth promotant implantation at lamb marking provides no later-life advantage, while wet season implantation provides a growth or liveweight advantage to young Merino ewes and this persists for a long period after implantation. Despite the lack of an effect of Ralgro on oestrus and pregnancy results, however, implantation of young breeding ewes of any age should not be carried out, due to the long term and negative effects on reproductive performance. Wet season implantation may be best used for animals intended for slaughter.


1989 ◽  
Vol 5 (1) ◽  
pp. 51-64 ◽  
Author(s):  
John Giobaguan Iyawe

ABSTRACTA total of 392 small mammals belonging to five species of small rodents and four species of shrews were caught. The small mammals and their percentage composition were Crocidura nigeriae (20.9%), Crocidura grandiceps (11.7%), Crocidura crossei (9.7%), Crocidura flavescens manni (20.4%), Mus musculoides (39.0%), Praomys tullbergi (11.5%), Lophuromys sikapusi (3.6%), Lemniscomys striatus (1.3%), and Arvicanthis niloticus (0.3%).There were monthly variations in the number of Mus musculoides and Crocidura nigeriae.In Mus musculoides breeding was at a maximum at the beginning and towards the end of the wet season and early dry season. In Crocidura nigeriae breeding was maximal during the wet season and low in the dry season.The seasonal changes in the age structure of the two most common species: Mus musculoides and Crocidura nigeriae, are described.


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