Semi-intensive Farming Research Articles

Extended-Spectrum Beta-Lactamase-Producing and Multidrug-Resistant Escherichia coli and Klebsiella spp. from the Human–Animal–Environment Interface on Cattle Farms in Burkina Faso

Extended-spectrum beta-lactamase (ESBL)-producing and multidrug-resistant Enterobacterales pose a major threat to both human and animal health. This study assessed the prevalence of ESBL-producing Escherichia coli (ESBL-Ec) and Klebsiella spp. (ESBL-K) on cattle farms in Ouagadougou, Burkina Faso, using a One Health approach. From May 2021 to September 2022, cattle faeces, farmers’ stools, their drinking water and farm soil samples were collected from semi-intensive and traditional farms. An ESBL-selective medium was used to obtain resistant isolates, which were further characterised using biochemical tests. Antimicrobial susceptibility testing was performed using the Kirby–Bauer disc diffusion method. ESBL-Ec and/or ESBL-K were detected in 188 of 322 samples (58.0%). The prevalence of ESBL-Ec isolates was 42.2% (136/322) and that of ESBL-K isolates was 24.5% (79/322). Notably, 156 of the 188 ESBL isolates (83.0%) exhibited multidrug resistance. The highest resistance rates were observed against tetracycline and cotrimoxazole. Importantly, no isolates showed resistance to meropenem, which was used to test for carbapenem resistance. This study highlights the presence of ESBL-Ec and ESBL-K among the humans, animals and environment of the cattle farms. Good hygiene and biosafety practices are essential to limit the potential spread of multidrug-resistant bacteria between different interfaces on farms.

The protein transition—environmental footprints of farmed fish, microalgae and chicken for food, a case study in Kenya

AbstractChallenges of land scarcity, climate change and water shortage are contributing to escalating the shortage of protein rich food in sub-Saharan Africa. In Kenya a total of 27.8% of the population was undernourished, and a total of 72.3% were categorised as moderately or severe food insecure in 2021–2022. The need to investigate alternative protein sources with less impacts on land, water and climate change, which potentially could replace, at least some of the current production of livestock as the main protein source, is getting increasingly urgent. The main aim of this study is therefore to conduct an environmental footprint analysis of favourable protein production systems in Kenya to evaluate environmental impacts on land, water, and climate. The methodological approach used in this study is referred to as environmental footprint analysis, which is applied to assess; (1) farmed fish in ponds, (2) farmed fish in solar based affordable recirculation aquaculture systems (A-RAS), (3) dried spirulina (Arthrospira Platensis), and (4) chicken from semi-intensive farms. The results show that the most promising alternatives to cattle production are dried spirulina produced in ponds, followed by fish produced in affordable recirculation systems (A-RAS) run on solar energy. Spirulina fully replacing beef production would reduce water usage with 34.7 billion m3/year, land/water surface area with 34.8 thousand km2/year, and GHG emission with 28.2 megaton CO2eq/year. For fish farmed in A-RAS, such replacement would reduce water, land and emissions with 30.7 billion m3/year, 32.0 thousand km2/ year and 23.0 megaton CO2eq/year, respectively. This study illustrates that it is possible to tackle urgent challenges of food and nutrition security for millions of people in sub-Saharan Africa and worldwide with a sustainable protein transition towards a more sustainable, inclusive production system of small-scale farmers, if making use of alternative protein sources, such as from solar based A-RAS and microalgae.

Occurrence of Abortion in Different Breeds of Goats Reared under Semi-intensive Farming System at Organized Farms in Semi-arid Region of India

Background: Abortion is a major health problem of animals including goats, which results in significant financial losses for the farmers. The aim of the current study was to determine the occurrence of abortion in different breeds of goats reared under semi-intensive farming system at the organized farms in the semi-arid region of India, and to determine the relationship between the parity, season, and pregnancy stage of the aborted goats with the incidence of abortions. Methods: The data on the caprine abortions was collected and analyzed. The caprine abortions that occurred at the organized farms under a semi-intensive management system were categorized according to the season at the time of abortion, parity and pregnancy stage of the aborted goats. The Chi-Square test and ANOVA methods were used for the statistical analysis of the abortion data. Result: The occurrence of abortion in goats (combined farm) had a significant association with seasons and stages of pregnancy, whereas it was not associated with parities. Barbari, Jakharana and Jamunapari goats individually showed significant differences in abortion rates across various seasons, but did not exhibit significant variation in abortion rates with respect to different stages of pregnancy or parities. In the study, the majority of abortions were found in the winter season, followed by the rainy and summer seasons; similarly, most of the abortions were noticed in the later stage of pregnancy, followed by the mid- and early stages. There was the highest abortion rate in the goats with parity 3 and above, followed by the first and second parities. Further investigation is required to validate the current findings. In conclusion, the study revealed that abortion rates in goats are significantly influenced by seasonal changes and the stages of pregnancy.

Newly adopted dromedary husbandry systems and breeding practices in the Algerian northern Sahara

Background: Traditional nomadic livestock farmers have adopted new lifestyles, management methods and husbandry practices to improve their livestock income and enhance the value of camel products, whose benefits are increasingly being recognized worldwide. Driven by a rising demand for camel products among urban consumers, these changes include a strong tendency for nomadic communities to settle near urban centers, the temporary stationing of part of the camel herd in urban and peri-urban areas, and the intensification of production in these areas. Aims: This paper aims to present the newly adopted dromedary husbandry practices, and discuss the products and services provided by dromedaries. Methods: Between September 2020 and March 2021, formal and informal interviews were carried out in three locations in the Algerian northern Sahara with 11 camel breeders, whoheld a total of 537 dromedaries (average 48.8 ± 4.36). Results: The study identified three types of dromedary farming systems: 70% of the farms were peri-urban,semi-intensive dairy farms established to meet the rising demand for camel milk, 23% were settled, intensive, peri-urban feedlot farms producing all categories of fattened dromedaries, especially young males, and 7% were settled, urban, and peri-urban dromedary racing farms dedicated to breeding dromedaries for racing and riding during local festivals, activities anchored in the traditions of the native population. The surveyed farms primarily generated income from the sale of milk and live animals, with manure and wool also contributing to their earnings. The food resources used for dromedaries were natural pastures, crop residues and harvest residues. Conclusion: The intensification of dromedary breeding appears essential to ensure the sustainability of this animal resource as it can improve reproductive potential, milk production, and the availability of young calves for fattening farms. The changes in practices identified in this study are enabling breeders, who are managing their livestock in guarded and semi guarded camel production systems, to increase their income.

Factors Associated with Morbidity and Mortality of Goat in Extensive and Semi-Intensive Farming Systems in the Eastern Province of Sri Lanka

The present study was conducted to identify the associated factors with morbidity and mortality of goats in extensive and semi-intensive farming systems. A sample of 266 goat farmers of three districts i.e., Ampara, Batticaloa and Trincomalee in the eastern province were randomly selected with the assistance of veterinary offices. A pre-tested questionnaire with face-to-face interviews, farm visits and observations were used to collect the data. The study found that goat farming is a male-dominant (>90%) activity regardless of the farming systems. Young and middle-aged farmers with better educations adopted semi-intensive farming systems while the older and poorly educated farmers adopted extensive farming systems while being self-employed. The factors i.e., ectoparasites, lack of feed, lack of water, age of the goats, rainy season, and the lack of veterinary services significantly associated (p<0.05) with morbidity and mortality of goats in both extensive and semi-intensive farming systems. The factors i.e., disease, poor housing, dry season and predator attack were not associated with morbidity and mortality of goats in semi-intensive farming systems whereas the association was significant (p< 0.05) in the extensive farming system. Hence, it is concluded that the semi-intensive farming system is effective in protecting goats from morbidity and mortality caused by disease, dry season, predator attack and poor housing compared to the extensive farming system. The factors associated with morbidity and mortality in extensive farming are inherent to the system except for the lack of veterinary services. J Bangladesh Agril Univ 22(3):369-376, 2024

Prevalence, antimicrobial resistance and genomic comparison of non-typhoidal salmonella isolated from pig farms with different levels of intensification in Yangon Region, Myanmar

In Myanmar, where backyard, semi-intensive, and intensive pig (Sus scrofa domesticus) farming coexist, there is limited understanding of the zoonotic risks and antimicrobial resistance (AMR) associated with these farming practices. This study was conducted to investigate the prevalence, AMR and genomic features of Salmonella in pig farms in the Yangon region and the impact of farm intensification to provide evidence to support risk-based future management approaches. Twenty-three farms with different production scales were sampled for two periods with three sampling-visit each. Antimicrobial susceptibility tests and whole-genome sequencing were performed on the isolates. The prevalence of Salmonella was 44.5% in samples collected from backyard farms, followed by intensive (39.5%) and semi-intensive farms (19.5%). The prevalence of multi-drug resistant isolates from intensive farms (45/84, 53.6%) was higher than those from backyard (32/171, 18.7%) and semi-intensive farms (25/161, 15.5%). Among 28 different serovars identified, S. Weltevreden (40; 14.5%), S. Kentucky (38; 13.8%), S. Stanley (35, 12.7%), S. Typhimurium (22; 8.0%) and S. Brancaster (20; 7.3%) were the most prevalent serovars and accounted for 56.3% of the genome sequenced strains. The diversity of Salmonella serovars was highest in semi-intensive and backyard farms (21 and 19 different serovars, respectively). The high prevalence of globally emerging S. Kentucky ST198 was detected on backyard farms. The invasive-infection linked typhoid-toxin gene (cdtB) was found in the backyard farm isolated S. Typhimurium, relatively enriched in virulence and AMR genes, presented an important target for future surveillance. While intensification, in terms of semi-intensive versus backyard production, maybe a mitigator for zoonotic risk through a lower prevalence of Salmonella, intensive production appears to enhance AMR-associated risks. Therefore, it remains crucial to closely monitor the AMR and virulence potential of this pathogen at all scales of production. The results underscored the complex relationship between intensification of animal production and the prevalence, diversity and AMR of Salmonella from pig farms in Myanmar.

First report of oriental theileriosis in the Intermediate Zone, Sri Lanka: Is Theileria orientalis type 7 always apathogenic?

PurposeTheileriosis in cattle has a significant economic implication for dairy production globally. Thus, it is crucial to investigate the prevalence of bovine theileriosis, the causative agent and genotypes of Theileria species in dairy cattle in the Kurunegala District in the Intermediate zone, where the third largest population of dairy cattle in Sri Lanka is present and experienced a substantial reduction in the cattle population recently. MethodsSixty blood samples and background data were collected from three dairy farms in Galpokuna (n = 20), Koulwewa (n = 20), and Andigama (n = 20) areas. Haematocrit was used to identify anaemia while Giemsa-stained blood smears demonstrated the presence of piroplasms. A Fisher's Exact Test (p < 0.05) compared the prevalence of infection among age groups and farms. PCRs using species-specific primers designed to amplify regions of MPSP and 18 s rRNA genes followed by sequencing of selected amplicons allowed phylogeny of the species detected. ResultsAll three farms had semi-intensive farming practices keeping animals in a ‘closed’ setup with limited movement. Theileriosis prevalence in dairy cattle was 55.0 % with no difference among the farms (Koulwewa: 65.0 %, Galpokuna: 50.0 %, Andigama: 50.0 %). One-third of the cattle (33.3 %) were anaemic based on haematocrit results but most showed mild anaemia. Anaemia was significantly higher in calves (45.0 %) than in adults (25.0 %; χ2 = 5.743; p = 0.03) tested positive for theileriosis. None of the animals showed any other signs of theileriosis. PCR revealed the presence of both T. orientalis (pathogenic or benign) and T. annulata (pathogenic). The sequencing data revealed that the T. orientalis genotype present in Kurunegala District is type 7. ConclusionThis is the first report on T. orientalis and T. annulata in dairy cattle in the Intermediate zone of Sri Lanka. The type 7 of T. orientalis was more common showing severe anaemia in calves while mild anaemia or no anaemia in adults and sub-adults. In immunologically intact animals, the reported genotype of the parasite can persist asymptomatically for life, occasionally causing a relapse, particularly under stressful conditions like pregnancy, lactation, and rapid changes in environmental conditions. However, the susceptibility of calves for pathogenic and apathogenic genotypes of T. orientalis and the carrier status of asymptomatic animals needs further investigation.

Prevalence and risk factors of reproductive health problems in dairy cows in Southern Ethiopia

Reproductive disorders are the leading cause of economic loss in the cattle industry, as they reduce the reproductive efficiency and lifetime productivity of cows. In Ethiopian dairy, without proper preventive measures, these disorders can have a severe impact on productivity. Therefore, it is crucial to identify the extent of these issues and the factors contributing to them in order to improve the health and productivity of dairy cows. This study aimed to assess the prevalence, type, and potential risk factors for reproductive health problems in dairy farms in Hawassa city and Wolaita Sodo town. We observed 391 pregnant and postpartum cows for reproductive disorders and used a logistic regression model to identify risk factors. The study found that 165 cows (41.6%; 95% CI: 36.8-46.5%) had at least one reproductive issue. The most common disorders included retained fetal membrane (11.6%), dystocia (10.5%), metritis (7.2%), abortion (5.6%), stillbirth (2.6%), uterine/vaginal prolapse (2.3%), endometritis (2.1%), and pyometra (0.5%). The risk of dystocia significantly increased with male calf deliveries (OR=2.9; p=0.004) and larger farm sizes (OR=2.1; p=0.039). Cows experiencing dystocia were 5.3 times more likely to have retained fetal membrane (p&lt;0.001). Heifers were significantly more likely to develop metritis (OR=5.1; p=0.001), as were cows with retained fetal membrane (OR=11.6; p&lt;0.001). The incidence of abortion was significantly elevated in cows from semi-intensive farms (OR= 5.3; p&lt;0.001). The study concludes that these reproductive health issues can significantly impact future uterine health, resulting in prolonged uterine involution. It is crucial to raise awareness among dairy farmers about effective herd health management practices to minimize losses.

Genetic parameters of body weight traits in Mithun (Bos frontalis) using animal model.

Mithun (Bos frontalis), a domestically raised herbivore, holds significant economic importance for the farming community of Northeast India. This study aimed to elucidate the genetic parameters governing Mithun body weight traits across different ages using data from the sole organized semi-intensive Mithun farm in India. Information was gathered from 110 Mithuns born over a period spanning from 2011 to 2022. Body weight taken at week 1(W1), 1-month(M1), 3-months (M3), 6-months (M6), 9-months (M9), 12-months (M12), 30-months (M30) and 45-months (M45) were considered for the study. The genetic parameters estimation employed the BLUPF90 suite of programs, incorporating univariate Gibbs sampler animal model with fixed effects; season and period of birth, and sex of the animal. Variance and covariance components, including direct additive genetic effects, were estimated. Heritability estimates for the eight body weight traits ranged from 0.47 ± 0.0050 to 0.50 ± 0.0043, indicating varying genetic influence across growth stages. Results revealed that Mithun herd has a substantial genetic variability for growth traits and therefore there is ample scope to select for a better growth rate. Here, we conclude that Month 12(M12) and Month 9(M9) body weights exhibit higher heritability, indicating potential for genetic improvement through selective breeding.

Molecular Detection and Serological Investigation of Newcastle Disease in Intensive, Semi-Intensive, and Backyard Production Systems in Central and Southwestern Areas of Ethiopia.

The purpose of this research is to detect Newcastle disease virus and to assess the seropositivity among backyard, semi-intensive, and intensive farms located in central and southwestern areas of Ethiopia. A total of 239 oropharyngeal and cloacal swab samples were collected from symptomatic birds found in Holeta, Burayu, Jimma towns as well as Seka Chekorsa and Nadhigibe woredas of Jimma Zone. In addition, ninety blood samples were collected from wing veins of unvaccinated birds found in the study areas of Jimma zone. Side-by-side information related to risk factors estimated to contribute to the susceptibility of the disease was collected by interviewing owners of sampled birds. Reverse transcription polymerase-chain reaction (RT-PCR) was conducted to detect NDV. Likewise, Enzyme-linked immunosorbent assay (ELISA) was performed to determine the seropositivity of ND. The proportion of samples where NDV was detected was 24.6%. Similarly, 68.9% of the sampled birds were seropositive. It was observed that adult birds were more likely to encounter the disease than youngs (OR = 11.6; 95% CI: 4.0-33.3; P = 0.000). Birds owned by respondents who leave diseased birds in the flock were more likely infected (OR = 6.2; 95% CI: 1.8-21.2; P=0.004) as compared to those isolated and mode of disposal of dead chicken significantly affect exposure (OR = 0.13; 95% CI: 0.10-4.88; P = 0.044). Likewise, access to veterinary services highly likely reduces susceptibility to the disease (OR = 12.4; 95% CI: 3.2-46.9; P = 0.000). It was also found that birds farmed intensively were the most at risk (OR = 2.8; 95% CI: 0.58-13.71; P = 0.199). Detection of ND from a significant proportion of sampled birds and their high seropositivity percentage revealed the circulation of the virus in the study areas.

Consumer Preferences for Native Chicken Meat in India: Implications for Sustainable Production and Household Dynamics

Indigenous and native chickens play a pivotal role in rural economies, providing income and food security. India is one of the world's top producers of poultry, with a total chicken population of 851.8 million in 2019 and 37.2% representing native or indigenous breeds. In recent years, the rising demand for native chicken meat and government-backed projects in India have led to a shift from traditional backyard chicken raising to semi-intensive and intensive farms, empowering marginalized communities and women. Consumer preferences for native chicken meat in India was examined in this study, employing a two-part model with a logit model and log-normal OLS model to analyse responses from 503 consumers. Additionally, factor analysis revealed nine key factors influencing attitudes. Gender, age, income, education, marital status, cohabitation, household size, the presence of seniors or children, and consumption frequency significantly shaped preferences. Factors such as psychological well-being, affordability, knowledge, nutrition, food quality, fitness, purity, and sustainability had negative effects on preference and quantity purchased. The study reveals a strong consumer preference for native chicken meat, attributed to its organic nature, including traditional farming and sustainable production. To enhance sustainability of semi-intensive and intensive native chicken farming, it is imperative to address pricing disparities and ensure the consistent availability of native chicken meat. Achieving long-term sustainability in native chicken farming requires aligning consumer demand with ethical and environmentally sustainable farming practices.

Mycobacterium tuberculosis complex in domestic goats in Southern Spain

Tuberculosis (TB) is a zoonotic infectious disease caused by bacteria belonging to the Mycobacterium tuberculosis complex (MTC), which can affect a wide variety of domestic and wild animal species. Although the role of goats as a reservoir of MTC bacteria has been evidenced, information about the circulation of MTC strains in this species is still very scarce. The aim of the present study was to determine the seroprevalence, spatial distribution, risk factors and MTC spoligotypes circulating in goats from Andalusia (Southern Spain), the Spanish region with the largest goat census and a hotspot area of TB in both cattle and wild ungulates. A total of 2155 serum samples from 80 goat flocks were analyzed by an in-house ELISA using the P22 protein complex as a coating antigen. Antibodies against MTC were detected in 473 goats (21.9%, 95% CI: 20.2–23.7) and the true seroprevalence was 22.3% (95% CI: 20.6–24.1). Seropositivity was found in 72 (90.0%) of the 80 flocks analyzed. The generalized estimating equation model showed that the management system (higher seroprevalence on intensive and semi-intensive farms), and the presence of hospital pens inside the regular stables, were risk factors potentially associated with MTC exposure in goats in Southern Spain. The spatial analysis identified a significant spatial cluster (p < 0.001) in Eastern Andalusia. A total of 16 different MTC spoligotypes, including five of M. caprae and eleven of M. bovis, were identified in goats between 2015 and 2022 in the study area, with SB0157 as the most frequently isolated. The results obtained indicate widespread and non-homogeneous spatial distribution of MTC in goat herds from Southern Spain. The high individual and herd-level seroprevalence values found suggest that goats could play a significant role in the maintenance and transmission of MTC in the study area. Our results highlight the importance of implementing control measures in this species.

Evaluation of Claw Lesions in Beef Cattle Slaughtered in Northern Portugal: A Preliminary Study

Claw diseases have a profound impact on cattle welfare, affecting behaviors such as grazing, rumination, rest, decubitus, and water consumption. This study aimed to assess the prevalence of claw lesions and classify them according to the ICAR Claw Health Atlas (International Committee of Animal Recording) in two slaughterhouses. The influence of claw lesions on carcass weight, classification, and fat deposition was also examined. Involving 343 crossbreed cattle from 103 different extensive or semi-intensive farms, this study found an animal prevalence of claw disorders at 65.8%, with a higher incidence in females (n = 207, 60.35%) compared to males (n = 136, 39.65%). Despite the observed prevalence, claw lesions were not influenced by age or sex (p &gt; 0.05). The main claw lesions identified, including heel horn erosion, double sole, and asymmetric claw, were consistent with the cattle management practices in the study area. These cattle were raised in small, rustic premises with uneven floors, utilizing a mix of manure and plant material as bedding and lacking access to pasture. Also, no negative economic impact was detected concerning carcass weight, classification, or fat deposition. Consequently, it was concluded that the presence of claw lesions in beef cattle raised under the characteristic management of this geographical area does not adversely affect animal health or farm economics.

The rank of intensification factors strength in intensive pond production of common carp (Cyprinus carpio L.)

Intensive common carp (Cyprinus carpio L.) pond production offers an alternative to traditionally practiced extensive and semi-intensive farming technologies. Global warming increases the scarcity of water available for aquaculture, requiring increased productivity per unit of used water. The present trial was conducted on intensive rearing of two-summer-old common carp (0.5 ± 0.1) kg. Fractional factorial design (24–1, resolution IV) was applied to identify how production performance is affected by the following four factors and their interactions: I) feeding rate: ad libitum (4%) vs. restricted (2%); II) stocking density: low (1.1 t/ha) vs. high (2.2 t/ha); III) aeration rate: low (11 kW/ha) vs. high (25 kW/ha); and IV) presence or absence of co-cultured species: monoculture vs. polyculture with pikeperch (Sander lucioperca L.) reared in cages. The feeding rate appeared to be the most influential factor in growth, meat quality, water quality, and stress parameters. Although the higher stocking density might be economically justified in the short term, due to impaired welfare it brings risks in the long run. The higher rate of artificial aeration showed a negative effect on meat and water quality; however, its cooling effect might be helpful in tackling issues with extreme water temperature. The test showed feasible cage production of pikeperch even in intensive pond production. The recommended goals for feasible intensification of common carp pond aquaculture are feeding regimes aiming at better feed utilization instead of growth maximization, stocking densities up to the limits of fish welfare (gross yield <11 t/ha), optimized paddle wheel aeration in favor of algae development (<11 kW/ha), and species/technology diversification.

Influence of Alevinage Time in the Optimization of Tambaqui Biomass Production in Semi-Intensive Fish Farming in the Northern Region of Amazonas

Objective: To evaluate the weight mix for the market obtained with variation in the pre-fixed fingerlings time, for the cultivation of tambaqui (Colossoma macropomum) in a semi-dug tank. Theoretical framework: The parameters evaluated regarding resources are, the tanks, each of which has its own capacity, its own state variable, which includes fish biomass, growth function and mortality rate. And identifying potential alternatives and making better decisions that optimize biomass production are important, but that take into account the reduction of its environmental impact. Method: The model incorporates two types of input variables. The discrete event variable, which comprises the number of fish in each batch, the number of tanks available, the time between the arrival of fingerlings in the system and the frequency of classification by weight for the market. The second refers to the continuous time variable, involving the weight of the fish, dissolved oxygen (DO) available to the fish, and feed consumption. Results and conclusions: The analysis showed that the decision variables are the quantities of fish, with the premise of final weight of 0.5 kg, 1 kg and 2 kg which are related to the hatching time pre-fixed at entry as “30, 40, 50, 60, 70, 80, 90, 100 days” in phase I, results in the optimization of production, target weight for the market as a function of time, in layout scenarios of 5 and 10 tanks, with the premise of harvesting in both, with Mix weight with 0.5kg, 1kg and 0.5kg, 1kg, 2kg to maximize net profit. Considering that the transition between growth phases is a stochastic process, which satisfies the Markov property. It was possible to define the balance between the input and output of the system. Research implications: The study is of great relevance, as it describes a sequential queue through the growth phases in relation to time, capable of determining the optimization of production with weight mix to maximize net profit. Originality/value: The research reveals that it is possible to use queuing theory analyzes in stochastic processes, evaluating the transition between time phases, which satisfies the Markov property.

Sero-Conversion Status of Different Breeds of Chickens Vaccinated With Newcastle Disease I2 Vaccine Type around Hawassa, Ethiopia

Chickens are vaccinated with live attenuated and inactivated vaccines in order to control Newcastle disease (ND). The vaccine can be administered by eye drop, aerosol or drinking water. Humoral antibodies usually appear within 6 to 10 days after vaccination in the serum and also locally in the upper respiratory tract and in the intestine. The efficacy of vaccinations can be estimated best with challenge experiments but they are expensive and time consuming. For the current study, a cross sectional study was conducted to determine the sero-conversion status of ND I-2 vaccine type provided to chicken reared in intensive, semi-intensive and extensive farms in Sidama region, Ethiopia. Of the total 401 samples collected from 29 various flock sizes 363(90.5%) were protective at individual bird level; whereas at flock level 86.2% (25/29) were met above 80% protection. Of 29 flocks 12 (42.4%) flocks were found 100% protective from the disease. The CV% varied between 21.2% and 122.3 percent among the flocks. The uniformity of average antibody titer for Bovans breed (CV%: 56.7) was comparatively better followed by Sasso (CV%: 69.2), Local breed (CV%: 73.1) and mixed breeds (CV%: 83). The overall average minimum, maximum and mean antibody titer for this study was 1179.8, 13840.1 and 5945, respectively. However, the minimum and maximum antibody titer for this study was 37.4 for Sasso breed with the age of 8 months and 20465.8 for mixed type of breed with the age of 12 months respectively. Significant antibody titer variation was observed among Breeds (p=0.018) and Ages (p=0.001) of the birds in this study. In general, the vaccination scheme for the current study revealed ND I-2 vaccine type was effective in protecting the chickens from the disease in respective of the age of birds at vaccination although the pattern of uniformity for antibody production is variably interrupted among the flocks.

Growth and carbon turnover of Piaractus mesopotamicus Holmberg, 1887 (Osteicthyes: Characidae): contribution of extruded feed and natural food.

Piaractus mesopotamicus, is a fish usually farmed in semi-intensive systems with access to natural food and supplementary feed. This study evaluates effects of feed allowance on the productive performance, carbon turnover and proportions of nutrient (carbon) contribution of feed and natural food for the growth of pacu. Juvenile fish were stocked in fiberglass tanks and fed to 100, 75, 50, 25, 0% apparent satiety (ApS), with a practical, extruded (C4 photosynthetic pathway) feed in a randomized design trial (n=3); plankton production for simulated semi-intensive farming system condition was induced by chemical fertilization. A control treatment was set up in tanks devoid of natural food. Data on muscle stable carbon isotope ratios were used to study carbon turnover using a relative growth-based model. Low variation of the δ13C impaired fitting a turnover model curve for the 0 and 25 % ApS treatments. Fish of the 100% and 75% ApS treatments reached circa 95% and 82.85% of the carbon turnover, respectively. Extruded feed was the main nutrient source for the growth of pacu in the semi-intensive, simulated farming condition. The current study contributes to the knowledge of the relationship between feeding rates and carbon turnover rates in the pacu muscle.

Lactation related changes of haematological parameters of female dromedary camels reared under semiintensive farming system in Algerian extreme arid region

Lactation related changes of haematological parameters of female dromedary camels reared under semiintensive farming system in Algerian extreme arid region

Enfoque ecosistémico del cultivo semiintensivo de Penaeus vannamei

The ecosystem approach to semi-intensive culture of Penaeus vannamei is crucial for understanding and managing water quality and planktonic communities in aquaculture systems. This study focuses on analyzing the interrelationship between structural and functional elements, using phytoplankton and zooplankton as bioindicators of water quality and trophic conditions. The objective is to provide detailed information on the dynamics of these communities in culture systems, which will improve survival, feed conversion and shrimp production. A systematic review was carried out using specific keywords in relevant scientific databases, which made it possible to collect updated and relevant information on the topic. The discussion focuses on the importance of phytoplankton as a primary producer, its influence on water quality and its role in the diet of shrimp. Recommendations for maintaining a beneficial balance of phytoplankton communities in cropping systems are detailed. Furthermore, the role of zooplankton as a crucial link in the food chain is analyzed, providing recommendations on the desirable amount of zooplankton in semi-intensive farming. Strategies to address challenges related to primary productivity and food chains in culture ponds are also discussed. In conclusion, this study highlights the importance of the ecosystem approach in shrimp farming, underlining the need to understand and manage planktonic communities to achieve successful and sustainable aquaculture

Expert knowledge–based system for risk assessment of the occurrence of Amyloodinium ocellatum in semi-intensive fish farms

The implementation of a system to assess the risk of Amyloodinium ocellatum occurrence in rearing ponds in fish farms located in southern Spain is a fundamental aspect to ensure the economic viability of these facilities. For this purpose, a computer program (called Amy) for Windows PCs and an application for mobile devices (AmyAPP), based on the Android operating system, were developed integrating transformation functions and weightings associated with environmental parameters and fish behavioural factors from which it is possible to estimate the level of risk of occurrence of A. ocellatum. The weights for each of the environmental parameters and behavioural factors were estimated from the responses of a panel of experts (the fish farmers) using a Delphi methodology. The results indicate that, under operational validation, Amy/AmyAPP responses were statistically sensitive to the occurrence of A. ocellatum outbreaks in sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) rearing ponds.