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Topic Review
Southern African Lion
The Southern African lion is a Panthera leo melanochaita population in Southern Africa. During the 20th century, lion populations in this part of Africa became fragmented and declined in several range countries due to loss of habitat and prey base, poaching and killing of lions to protect livestock and human life. In 2005, a Lion Conservation Strategy was developed for Southern and East Africa. Today, lion populations are stable only in large protected area complexes. In intensively managed protected areas in Botswana, Namibia, South Africa and Zimbabwe, they increased since the turn of this century. The scientific name P. l. melanochaita was proposed for the Cape lion in 1842 that was eradicated in the mid-19th century. P. l. melanochaita differs genetically from P. leo leo; the two subspecies probably diverged at least 50,000 years ago.
  • 1.2K
  • 18 Oct 2022
Topic Review
Enterococcus faecium EF2019
Weaning is the most important and critical period in rabbits breeding, when only small dietary and/or environmental changes can disturb the stable microbial population/fermentation and gut health, leading to digestive dysbiosis, increased morbidity/mortality and big economic losses. Control of the microbiota, prevention of digestive disturbances and improving gut health and immunity can be achieved through the natural substances application in rabbit nutrition. Probiotics are frequently used in rabbits farms, however, the most of them are non-autochtonous (have a different origin than the rabbits ecosystem), while the “in vivo” administration of bacteriocins (antimicrobial substances produced by bacteria, which usually possess also probiotic properties) in these animals are often limited and has become an area of research activity. Therefore, we focused on improving rabbits health using the autochtonous strain Enterococcus faecium EF2019(CCM7420; fresh culture, lyophilized form) and its enterocin (Ent7420) in broiler rabbits. During these experiments, the following effects of the strain and its enterocin were observed: improved average daily weight gain and feed conversion ratio, good colonization ability of the tested strain (maximum counts in first 2-3 weeks of application), increased lactic acid bacteria and reduced coagulase-positive staphylococi including S. aureus, coliforms and clostridia population as well as the Eimeria sp. oocysts counts in the rabbits gut. Both additives showed a tendency to modulate the serum biochemistry parameters (increased level of total proteins, glucose, triglycerids) and to stimulate the blood phagocytic activity and improved jejunal morphology (enlargement of the absorption surface in jejunum, higher villi height:crypt depth (VH:CD) ratio). The physico-chemical properties of rabbit meat was not negatively affected by the CCM7420 strain, while the meat iron content significantly increased during its application, which improves the rabbit meat quality. It could be also emphasized that knowing the probiotic properties and the ability of Enterococcus faecium CCM7420 to produce enterocin Ent7420 with antimicrobial effect is of great interest mainly in the case of several disease/pathologies, such as Epizootic Rabbit Enteropathy, which are difficult to prevent and combat because their etiology is not known and there are no vaccine. This strain is the main component of the Prorabbit probiotic preparation, which is often used in Slovak rabbit farms (at dosage 1-2 g/animal/day for 21 days as prevention and 3 g/animal/day with therapeutic effect; resolved in water or mixed into feed).
  • 1.2K
  • 26 Oct 2020
Topic Review
Locust Bacterial Symbionts
Locusts have been devastating vegetation and agriculture since ancient times. The formation of huge swarms that migrate long distances is a hallmark of the locust phenomenon. An important aspect of locusts’ natural history is that of their interaction with the bacteria they harbor in and on their body. These locust-associated bacteria have been shown to affect certain physiological traits (such as immunity and swarm cohesion), as well as possibly also being affected by differentfactors in the locust biology. This review summarizes our current understanding of the locust-bacterial interaction. We focus on identifying the relevant bacterial strains and their locations within the insects; the role of the bacteria and their importance to their host’s life; the mechanism of transmitting important bacteria across locust generations; and more. Finally, we offer some new perspectives and research directions that could broaden our understanding of the locust-associated bacteria and their tentative instrumental role in locust outbreaks.
  • 1.2K
  • 19 Oct 2020
Topic Review
List of Canis Species and Subspecies
Canis, the genus of mammals commonly known as wolves, dingos, dogs, coyotes, and jackals, contains several living species, many divided into numerous subspecies, as well as numerous recently extinct and extinct prehistoric species. Domestic dogs are not usually granted taxonomic variety names below the level of either their species name, or subspecies name so they do not appear here with their popular breed names as individual entries. The New Guinea singing dog and any other varieties of subspecies appear as individual entries here when their taxonomic considerations now suggest that they are varieties of subspecies other than domestic dogs, such as of dingoes. References for taxonomic classification, issues, and current considerations, especially in light of DNA revelations year to year, are found in the articles on individual canids; as this article is only a list, the extensive literature and specifics of these issues for each canid are beyond the scope of reference notes here. Furthermore, articles on the species in this list's section headings, and details of their evolutionary, divergent, interbreeding, geolocational and human-culture mediated shifts contain references on which this list relies when including and positioning its entries. References to this article are thus of two sorts, those pertaining to wholesale sourcing of entries, especially those that do not yet have their own Wikipedia articles, and the far more extensive references in existing Wikipedia articles for each entry, header species, and other relevant taxon.
  • 1.1K
  • 22 Nov 2022
Topic Review
Pseudorabies Virus
Pseudorabies, or Aujeszky’s disease, is a notifiable worldwide infection of domestic and feral swine that causes economic losses for the swine industry. In domestic pigs, the virus is responsible for nervous and/or respiratory symptoms; in pregnant sows, it is one of the major causes of stillbirth, mummification, embryonic death, and infertility (SMEDI). It is known that PRV infection in wild boar is associated with low pathogenicity and attenuated or absent symptomatology, but limited information is available about the ability of the virus to infect the foetuses of infected wild boar pregnant sows. Due to scarce information about the reproductive consequences, we investigate the possible intrauterine vertical transmission of the virus in wild boar pregnant sow living in a highly infected area. A number of 54 hunted wild boar were sampled during 2018–2019, and blood, genital and nasal swabs, placenta, and fetuses were collected for serological and molecular investigations. A seroprevalence of 74% (40/54) was detected, while 1/24 pregnant sow and 1/24 pooled foetuses tested positive by PCR (gene gB). This is the first evidence of viral detection in foetuses from seropositive pregnant wild boar. This finding suggests the possible pathogenetic role of PRV on pregnancy in wild boar and the existence of an additional transmission route.
  • 1.1K
  • 28 Oct 2020
Topic Review
Leishmania Major and Leishmania Donovani
Leishmania are protozoa belonging to the Phylum Euglenozoa Cavalier-Smith, 1981; Class Kinetoplastea Honigberg, 1963; order Trypanosomatida Kent, 1880; family Trypanosomatidae Doeflein, 1901 and subfamily Leishmaniinae, Maslov and Lukes 2012. The genus Leishmania is further divided into four subgenera, L. (Leishmania) Safjanova 1982, L. (Viannia) Lainson and Shaw, 1987, L. (Mundinia) Shaw, Camargo and Teixeira 2016 and L. (Sauroleishmania) Ranque 1973 [1]. Members of the first three subgenera are causative agents of leishmaniasis, the worldwide distributed, vector-borne human and veterinary disease. The main insect vectors are phlebotomine sand flies (Diptera: Phlebotominae). Human leishmaniases are highly variable in their clinical manifestation, ranging from self-healing cutaneous lesions to serious visceral forms, life-treating if untreated. The main representative of the zoonotic cutaneous leishmaniasis in the Old World is Leishmania major, distributed from North and West Africa through Sahel belt and the Middle East to Central Asia, Mongolia and south-west Asia. This species is transmitted by sand flies of the subgenus Phlebotomus (Phlebotomus). The sores appear at the site of insect bite and the necrotic process results in large, open and wet lesions which cure without treatment.  Several lesions may occur simultaneously. Reservoir hosts of L. major are various rodents, humans getting infected incidentally. Leishmania donovani is the causative agent of visceral leishmaniasis, called also kala azar. Fully developed kala azar is characterized with anaemia, haepatosplenomegaly and progressive cachexia and may be fatal if untreated, but subclinical or asymptomatic cases are frequent. The main vectors are P. (Larrousius) orientalis in East Africa and Phlebotomus (Euphlebotomus) argentipes in the Indian peninsula. The disease is regarded as anthroponotic in Indian peninsula while involvement of reservoir animals has been suggested in East Africa [2].
  • 1.1K
  • 09 Oct 2020
Topic Review
State-of-the-Art Vaccine for Aquaculture Use
Infectious diseases caused by bacteria, viruses, or parasites are the major causes of mortality and economic losses in commercial aquaculture. Some pathologies, especially those of bacterial origin, can be treated with commercially available drugs, while others are poorly managed. In fact, despite having been recognized as a useful preventive measure, no effective vaccination against many economically relevant diseases exist yet, such as for viral and parasitic infections.
  • 1.1K
  • 01 Mar 2021
Topic Review
Murciano-Granadina Goats
Murciano-Granadina goat is one of the oldest and most representative livestock breeds of Spain. There are some references to its existence dating back to the fifteenth century, especially with respect to the Granadina population (Rodero et al. 1992). The first modern reference to the breed is dated in 1893 (Aragó 1893) but it considered Murciana and Granadina, whose names derivate from the Spanish provinces in which they were raised, as two separate breeds, a situation that was maintained until the first official recognition of the Spanish breeds in 1933. According to Aparicio (1947) both Murciana and Granadina breeds are modern evolutions of the European Capra aegagrus goat branch, so that they are very close to each other from an evolutionary point of view, but still they hold important genetic differences as it has been highlighted by the tests carried out with molecular markers by Martínez et al. (2010), differences which could support  their recognition as independent breeds. Anyway, the integration of these two original breeds into a single racial entity was strictly an administrative decision took in the seventies during the past century. In those years, the Spanish government decided to follow the international recommendation to fusion close breeds in order to obtain higher census that permitted to extend the intensity of selection and the consequent bigger genetic progress. Today this decision is severely criticized because it meant the erosion of the Granadina population, leading it near extinction, in spite of remarking the important adaptive capacity of this population to the altitude (more than 2500 m) and the heat and hydric stress. Presently, the new extensification of management systems and the effects of climatic change make the Granadina genotypes very demanded, which show the best performances under hard conditions.
  • 1.1K
  • 16 Sep 2021
Topic Review
Three-Dimensional Bone Phantom
3-D surgical planning for restorative osteotomy is costly and time-consuming because surgeons need to be helped from commercial companies to get 3-D printed bones. However, practitioners can save time and keep the cost to a minimum by utilizing free software and establishing their 3-D printers locally. Surgical planning for the corrective osteotomy of antebrachial growth deformities (AGD) is challenging for several reasons (the nature of the biapical or multiapical conformational abnormalities and lack of a reference value for the specific breed). Pre-operative planning challenges include: a definite description of the position of the center of rotation of angulation (CORA) and proper positioning of the osteotomies applicable to the CORA. In the present study, we demonstrated an accurate and reproducible bone-cutting technique using patient-specific instrumentations (PSI) 3-D technology. The results of the location precision showed that, by using PSIs, the surgeons were able to accurately replicate preoperative resection planning. PSI results also indicate that PSI technology provides a smaller standard deviation than the freehand method. PSI technology performed in the distal radial angular deformity may provide good cutting accuracy. In conclusion, the PSI technology may improve bone-cutting accuracy during corrective osteotomy by providing clinically acceptable margins.
  • 1.1K
  • 09 Nov 2020
Topic Review
Escherichia Coli
Escherichia coli are facultative, anaerobic Gram-negative rods with many facets. Within resistant bacterial populations, they play an important ecological role and can be used as a bioindicator of antimicrobial resistance. All animal species used for food production, as well as humans, carry E. coli in their intestinal tracts; plus, the genetic flexibility and adaptability of this bacteria to constantly changing environments allows it to acquire a great number of antimicrobial resistance mechanisms. Thus, the prevalence of antimicrobial resistance in these commensal bacteria (or others, such as enterococci) can be a good indicator for the selective pressure caused by the use of antimicrobial agents, providing an early warning of the emergence of antimicrobial resistance in pathogens. As many as 90% of E. coli strains are commensals inhabiting the intestinal tracts of humans and warm-blooded animals. As a commensal, it lives in a mutually beneficial association with its hosts and rarely causes diseases. However, E. coli also remains as one of the most frequent causes of several common bacterial infections in humans and animals. In humans, it is the prominent cause of enteritis, community- and hospital-acquired urinary tract infection (UTI), septicemia, postsurgical peritonitis, and other clinical infections, such as neonatal meningitis, while, in farm animals, it is more prominently associated with diarrhea. On a global scale, E. coli can be considered the most important human pathogen, causing severe infection along with other major bacterial foodborne agents, such as Salmonella spp. and Campylobacter. Thus, the importance of resistance in E. coli, typically considered a benign commensal, should not be underestimated.
  • 1.0K
  • 17 Feb 2022
Topic Review
Canine Heat-Related Illness
Heat-related illness - more commonly known as "heat stroke" - is a potentially fatal disorder that can affect both man and animals. The condition has two main causes: exertional and environmental heat. Exertional heat-related illness occurs either when a dog is active in a hot environment, or associated with strenuous and typically prolonged activity in any temperature. Environmental heat-related illness occurs when the ambient temperature and humidity increase beyond the dog's cooling limits, cases of environmental heat-related illness typically occur during heatwave events.  
  • 1.0K
  • 17 Aug 2020
Topic Review
Maternal Placenta Consumption in Mammals
Placentophagia is a common mammalian behavior, and the first scientific study of the potential effects of human maternal placentophagia on lactation was in 1917. More recently, in the 1970s, human placentophagia was reported in North America with a trend toward increased consumption. There are different hypotheses about the women and nonhuman mammals’ motivation towards placentophagia, but few have been subject to hypotheses testing. In women, the controversy continues; on the one hand, researchers attribute benefits like increased breast milk, weight gain in newborns, decreased postpartum depression and fatigue, and improved mothers’ mood. In contrast, bacterial or viral infections, hormonal, or trace elements that could become toxic for both the mother and baby are reported as possible health risks. Other reports argue a lack of scientific rigor to support the self-reported benefits of placentophagia. Also, the way the placenta is prepared (raw, cooked, dehydrated, processed, or encapsulated) alters its components, and thus the desired effects.
  • 1.0K
  • 07 Jan 2021
Topic Review
Long-Chain Polyunsaturated Fatty Acids
The effects of long-chain polyunsaturated fatty acids (LC PUFAs) have been frequently investigated in sows because the profitability of pig production depends mainly on reproduction performance. According to the results of the previous studies, n-3 fatty acids can postpone the time of parturition, decreasing the synthesis of prostaglandins, which are necessary for uterus contraction during labour. These effects could also be useful during the post-weaning period when low prostaglandin levels are indispensable for embryo survival. The n-3 fatty acids fed during the lactation period secreted in milk, may improve piglet performance. Despite the numerous previous field trials, there are no current feeding recommendations available for PUFAs in swine nutrition. In finding the appropriate dose of n-3 PUFAs in terms of sow nutrition, the n-6 PUFAs levels in the given feeds must be taken into account to ensure that there are no significant reductions in the final n-6/n-3 ratio.
  • 1.0K
  • 27 Oct 2020
Topic Review
Maedi-Visna in Dairy Sheep
Maedi-visna in sheep is a chronic viral disease with worldwide distribution causing significant monetary losses in the sheep sector. Lack of effective treatment or vaccines, knowledge gaps regarding the epizootiology of the disease (e.g. significance of vertical and horizontal transmission) and the scarcity of protocols for the early and efficient diagnosis of maedi-visna infections are the major obstacles in the implementation of universally accepted control programs. The diagnostic methods currently used are based on the detection of either antibodies or the viral genome. In general, accuracy, sensitivity and specificity of the available serological and molecular assays vary and therefore, modifications on the diagnostic protocols on an evidential basis are necessary. Therefore, the combination of diagnostic assays and the development of effective strategies for mass implementation thereof are critical targets to achieve and constitute major challenges in maedi-visna research field.
  • 995
  • 28 Oct 2020
Topic Review
Elovl4 genes in Sparus aurata
Very long-chain (˃C24) fatty acids (VLC-FA) play critical roles during early development of vertebrates, since these compounds are accumulated in the rapidly forming neural tissues, ensuring their normal function. However, despite their putative importance, the study of VLC-FA in fish is scarce. Biosynthesis of VLC-FA is carried out by the so-called elongation of very long-chain fatty acid 4 (Elovl4) proteins and, consequently, the complement and function of these enzymes determine the capacity that a given species has for satisfying the physiological demands for VLC-FA, especially during its early development. The present study aimed to characterize elovl4 genes from the marine teleosts Sparus aurata and Solea senegalensis, and determine the function of the corresponding encoded proteins. Moreover, the tissue expression pattern of elovl4 genes was determined. The results confirmed that both fish species possess two distinct Elovl4 proteins termed as Elovl4a and Elovl4b based on their homology to the zebrafish orthologs. Functional assays in yeast denoted that both Elovl4a and Elovl4b from both species had the capability to elongate C20-24 fatty acid precursors to VLC-FA products. However, Elovl4b appeared to have a higher activity than Elovl4a elongating all the polyunsaturated fatty acid substrates assayed to longer chain polyunsaturated products, especially on the n-3 series. Gene expression results indicated that, although elovl4 transcripts were detected in most tissues analyzed, elovl4 genes were more strongly expressed in both species neural tissues such as brain and eyes, which showed the highest expression levels of elovl4a and elovl4b, respectively. These results are consistent with the functions of Elovl4 from other vertebrates. Importantly, these findings contribute to a better understanding of the VLC-FA biosynthetic pathway in marine teleosts, highlighting the crucial role that Elovl4 products carry out for the correct development and maintenance of neurophysiologic functions during early stages of the fish development.
  • 994
  • 28 Oct 2020
Topic Review
Animal Resilience
Resilience is conceived as a dynamic developmental process involving the achievement of positive adaptation within the context of significant adversity. Resilience is not a unique ability but rather a set of capacities of a system put in place to absorb a disturbance and to reorganize while trying to retain the same function, structure, and identity. This study describes the characteristics and the molecular mechanisms of resilience to understand the core elements of resilience and its indicators.
  • 993
  • 08 Jan 2021
Topic Review
Oils in Feed and Egg Quality
Eggs are a valuable source of protein and fat in the human diet. Due to continuous improvement in the production performance of laying hens, the requirements regarding the feed energy of laying hens are increasing. Oils, which are the main energy sources in feed, exert a substantial effect on the production performance and egg quality of laying hens.
  • 978
  • 22 Dec 2021
Topic Review
Neurophysiological Mechanisms of Cow–Calf Bonding
In buffalo, bonding is very particular due to the expression of specific behaviors, such as allo-suckling and communal rearing.
  • 972
  • 19 Apr 2022
Topic Review
Avian Influenza Virus in Bangladesh
Highly pathogenic H5N1 and low pathogenic H9N2 avian influenza viruses are circulating in Bangladesh since 2007 causing serious economic losses to the country. Multiple virus introductions of different clades of HPAIV H5N1, reassorted genotypes, and on-going diversification of LPAIV H9N2 create a highly volatile virological environment which potentially implicates increased virulence, adaptation to new host species, and subsequent zoonotic transmission.
  • 971
  • 22 Jul 2020
Topic Review
Felid Cardiopulmonary Nematodes
Felid cardiopulmonary nematodes belong to the superfamily Metastrongyloidea and mainly to the species Aelurostrongylus abstrusus, Troglostrongylus brevior, Oslerus rostratus (parasites of the airways), and Angiostrongylus chabaudi (parasite of the pulmonary artery and right chambers of the heart).
  • 963
  • 26 Jan 2021
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