Bhutan Journal of Animal Science https://ojs.moal.gov.bt/index.php/bjas <p>The Bhutan Journal of Animal Science (BJAS), founded in 2016, is an English-language double-blind peer reviewed journal on livestock science. BJAS is supervised by the Department of Livestock, Ministry of Agriculture and Livestock, and financed by the Royal Government of Bhutan. BJAS publishes research, reviews, reports on all aspects of small and large ruminants, equine, poultry, aquaculture, and apiculture. BJAS also accepts livestock associated research reports on climate change, sustainable development, and rural livelihood. BJAS requires academic papers and research reports to display universal, strategic and innovative characteristics in both theory and practice. BJAS acts as a forum for sharing information between researchers, policy makers and practitioners. BJAS is published annually.</p> Department of Livestock en-US Bhutan Journal of Animal Science 2520-0194 PREVALENCE AND ZOONOTIC POTENTIAL OF ANCYLOSTOMIASIS IN DOGS IN BUMTHANG DISTRICT, BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/182 <p>Canine hookworm infection is endemic in Southeast Asian countries. Canine hookworms include <em>Ancylostoma caninum</em>, <em>Ancylostoma braziliense</em>, <em>Ancylostoma ceylanicum</em> and <em>Uncinaria stenocephala </em>which represent a potential public health concern. In human, canine hookworms can cause patent enteric infections and cutaneous larval migrans. However, there are limited data available on the prevalence of canine hookworms in Bhutan. This study was conducted to determine the prevalence of ancylostomiasis among dogs in Bumthang district. Faecal and whole blood samples were collected from 177 dogs (100 free-roaming and 77 pet dogs) in Bumthang. Faecal samples were processed and examined for hookworm eggs using standard parasitological methods. The overall prevalence of ancylostomiasis in Bumthang was 5.6% (95% CI; 2.25-9.05). The prevalence was highest in Chhoekhor Toed with 9.1% followed by 8.8% in Chamkhar town, 5.4% in Tang, 2.6% in Ura and none in Chumey. The prevalence was comparatively higher in pet dogs (6.5%, 95% CI; 0.73-9.27) than free-roaming dogs (5.0%, 95% CI; 0.99-11.99). However, there was no statistical significance between the prevalence in pet dogs and free-roaming dogs (<em>p</em>&gt; 0.05). This study indicates that dogs in Bhutan are known reservoir hosts of human hookworm infection. The finding necessitates the inclusion of dogs in any interventions to combat human hookworm infections in the country. Further, the molecular characterization of the <em>Ancylostoma</em> species needs to be carried out in order to understand <em>Ancylostoma</em> species and species-specific potential public health risks in the country.</p> Jambay Dorjee Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 10 18 AGE-RELATED GROSS AND HISTOMORPHOLOGICAL CHANGES IN SMALL INTESTINE OF SAKINI CHICKEN https://ojs.moal.gov.bt/index.php/bjas/article/view/187 <p>The study was carried out to assess the histo-morphological changes in small intestine of <em>Sakini</em> chicken from October 2021 to March 2022. Ninety-two, day-old chicks of <em>Sakini</em> breed of both sexes were considered for the study. These birds were reared under the standard husbandry practices and fed with layers starter pellet feed containing 20% crude protein, 3000 Kcal/kg metabolizable energy and <em>ad libitum </em>water for 56 days. &nbsp;Forty birds of five different age groups from day 1, day 14, day 28, day 42 and day 56 (eight birds per age group) of trial period were sacrificed. The findings indicated that live body weight gained significantly from 25.22 gm to 533.63 gm as age progressed from day one to day 56. Amongst sex, males had significantly higher body weight (582.25 gm) than females (485.00 gm) at day 56. Length and weight of duodenum, jejunum and ileum increased significantly up to day 28 and day 42 and became steady thereafter. A significant increase in the relative weight of small intestine was observed up to day 28 showing the growth of the small intestine was higher than the rest of the body at an earlier age. Histologically, villus length of duodenum, jejunum and ileum increased from 375.65 µm, 259.25 µm and 209.25 µm at day one to 834.18 µm, 610.57 µm and 447.01 µm at day 56 while apparent villus area increased from 23266.55 µm², 14053.17 µm² and 12430.71 µm² at day one to 109351.55 µm², 69702.34 µm² and 44702.80 µm² at day 56 respectively. The result showed that delayed stabilization of relative weight and length resulted in slower growth of <em>Sakini </em>chicken which indicates digestion and absorption capacity increased with advancement of age after stabilization of relative weight and length. An increase in villus height and villus surface area of <em>Sakini</em> chicken were the compensatory mechanism to fulfill the increase in nutrient demand of the body. Villus length, villus width, apparent villus area and ratio of villus height and crypt depth were highest for duodenum followed by jejunum and ileum at all ages. These parameters are positively associated with the live body weight so at the initial stage of life duodenum plays the vital role for maintaining the body weight as it is principal site for digestion and absorption. This present research provides novel findings on the baseline information on histo-morphological changes in small intestine of Sakini chicken which can be used as reference for further digestive studies. &nbsp;</p> Sanjay Paudel Anjani Mishra Subir Singh Saroj Sapkota Neena Amatya Gorkhali Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 19 32 THE PERFORMANCE OF NATIVE DUCK AND FRESHWATER MUSSELS REARED IN CONCRETE POND SYSTEM https://ojs.moal.gov.bt/index.php/bjas/article/view/184 <p>The present study investigated the performance of Duck mussels and freshwater mussels reared in a concrete pond system. The study also identified appropriate host fish species for completing a unique reproductive cycle of the native mussels to carry glochidia during the larval stage. A total of 1200 numbers of healthy mussels – 600 each Duck mussels and freshwater mussels were stocked in the captive condition with suitable physicochemical parameters like water movement, water exchange, water temperature, dissolved oxygen, and pH. Both duck mussels and freshwater mussels were fed on natural productivity integrated with native fish species as the treatment. Mussels were provided plant-based substrate to derive natural food through a natural weathering process limiting an external feed supplementation on a trial and error basis. Variables such as total body weight, shell length, shell height, shell depth, survival rate, and host fish species were assessed. Growth indices data were analyzed using SPSS version 25.0 through a t-test to compare the various performance. The present study revealed that freshwater mussels had better growth (ADG = 0.23) and survival rate than Duck mussels (ADG = 0.07). The latter species also exhibited satisfactory growth performance under concrete pond settings. Duck mussels and freshwater mussels attained 32.69 ± 12.07g and 112.77 ± 33.67g, respectively after six months of the culture period. Both mussels had host fish species compatibility with native fishes such as Barna baril (<em>Barilius barna)</em>, zebrafish or zebra danio (<em>Danio rerio)</em> and Ticto barb (<em>pethia ticto) </em>found in the Southern River system. It is evident from 90% survival rates that natural productivity adequately enabled growth performance and natural propagation. Considering the growth performance, natural propagation efficiency, and promising survival rate of the current findings, both freshwater and duck mussels qualify for food production. </p> Pema Thinley Renchen Lhamo Cheten Dorji Drukpola Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 55 62 COMPARISON OF FORAGE YIELD AND NUTRIENT QUALITY OF HIGHLAND OAT VARIETIES IN BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/186 <p>The on-farm experiments were conducted to evaluate forage yield and nutritional quality of two promising highland oat varieties namely Gansu 2 and Qingyin oats under the farmers’ field management conditions in Bhutan with stampede oats variety as control. The experiment was laid out in randomized complete block design with three replications. The variety Gansu oat 2 produced significantly higher green forage yield than variety stampede. However, there was no significance difference in essential nutrient (Crude protein) content between new and existing oat varieties. The study concluded that variety Gansu oat 2 is suitable for forage production under temperate and sub-alpine climatic conditions and is a viable alternate oat variety to address winter fodder shortage in highland districts of Bhutan</p> Wangchuk Kheng Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 63 73 IMPACT OF COVID-19 ON COMMERCIAL BROILER FARMING IN SAMTSE DISTRICT https://ojs.moal.gov.bt/index.php/bjas/article/view/185 <p>The study was designed to assess the impact of covid-19 on broiler farming in Samtse dzongkhag. Ninety-three broiler farmers were randomly selected and interviewed face to face using a set of semi-structured questionnaires. More than half of the respondents (72.7%) mentioned that the broiler farms have been temporarily discontinued, while some respondents (24.7%) have continued and have quit broiler farming (1.1%) after the covid-19 pandemic. Consequently, the broiler population in 2020 has decreased by about 30% compared to 2019. Before the pandemic, about half of the farms were micro-farms (52.7%), semi-commercial farms (46.2%), and commercial farms (1.1%) were operational, however during covid-19, more than half were micro-farms (78.5%) and semi-commercials broiler farms (21.5%). A significant association was found in the scale of broiler farming during covid-19 compared to the past (χ2(2) =14.118, p=0.001. About half of the respondents (46.2%) considered broiler farming as the primary source of income for the farmers, followed by betel nut (32.3%) and vegetable farming (21.5%) before the pandemic. However, during the pandemic, more than half of the respondents (59.1%) stated that betel nut is the primary source of income, followed by vegetables (40.9%). All the respondents mentioned that the availability of feed and getting day-old chicks on time during covid-19 owing to the national lockdown (restricted movement) were the major constraints to continuing and sustaining broiler farming. Besides, all respondents mentioned that the market access to sell broiler meat became increasingly challenging during covid-19 when compared to the past. Thus, it is suggested that the government has to devise an appropriate strategy, post pandemic measures and support to encourage the broiler farming communities to revive, promote and sustain broiler farming in the country. To revive, promote, and sustain broiler-farming communities post-pandemic, a combination of financial support, market development, training and education, research and development, infrastructure development, encouragement of small-scale farming, and partnership and collaboration can help to revive, promote and sustain broiler-farming communities post-pandemic.</p> Janga Bdr Gaylal Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 81 89 LENGTH-WEIGHT RELATIONSHIP AND RELATIVE CONDITION FACTOR OF A MIGRATORY AND A RESIDENT HILL STREAM FISH FROM HYDROPOWER-IMPACTED TRIBUTARIES OF PUNATSANGCHHU RIVER, BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/189 <p>This study aimed to determine the length-weight relationship (LWR) and access the relative condition factor (K<sub>n</sub>) of migratory fish, <em>Schizothorax richardsonii</em> and resident fish, <em>Garra gotyla</em> from the tributaries of Punatsangchhu River within the vicinity of the hydropower development area. The sampled tributaries were categorized into three zones: upstream, fragmented or impacted zone and downstream zone. Both species indicated significant negative allometric growth. The allometric form of LWR for <em>S. richardsonii</em> and <em>G. gotyla</em> is established as W = 0.0155L<sup>2.6806 </sup>and W = 0.0161L<sup>2.7506</sup>, respectively. The K<sub>n</sub> of both species were &gt; 1 at the downstream zone only. One-way ANOVA and Tukey HSD test indicated significantly lower K<sub>n</sub> in the fragmented zone and upstream zone as compared to the downstream zone for <em>S. richardsonii. </em>An unpaired two-sample t-test indicated insignificant differences in K<sub>n</sub> of <em>G. gotyla</em> between the downstream and fragmented zone. This study reflects the greater impacts of hydropower development on fragmented zone and migratory fish as compared to resident fish. The present study will help in the improvement of long-term monitoring of the impacts of hydropower development on fisheries and standardization of fisheries monitoring programs in Bhutan.</p> Gopal Prasad Khanal Pemo Singye Tshering Tashi Dorji Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 90 99 COMPARATIVE PERFORMANCE OF PIGS FED WITH CASSAVA BASED DIETS AND COMMERCIAL FEEDS https://ojs.moal.gov.bt/index.php/bjas/article/view/172 <p>This study was conducted to explore the possibility of replacing maize component in pig feed with cassava chips. Sixteen sows were allotted into two groups – experiment and control group equally. The animals in the experimental and control group were fed diet containing 50 % cassava chips and usual commercial sow ration, respectively, for a duration of one production cycle from April to November 2022. Animals in both groups were raised under similar management practices. Parameters such as body condition score and back fat thickness, and breeding parameters namely conception rate, dry period, litter size, average birth weight, average weaning size, average weaning weights, post-weaning weights of piglets were compared between two groups. Independent Sample t test, Pearson correlation and descriptive statistics were used to analyse the variables. The findings revealed no significant differences in non-reproductive and reproductive parameters except for the post weaning weight gain (p &lt; 0.001) of the piglets. The piglets born from the experimental group attained higher post weaning weights than the control group. The study recorded average dry period and conception rate of about 5 days and 11.63 days; and 50 % and 75 % for the experiment and control groups, respectively. The average post-weaning weights of piglets recorded was 9.24 and 6.94 kg for the experiment and the control group, respectively. The study concludes and suggests that the cassava chips can be used as an alternative basal ingredient and can replace 50% of maize in pig diet thereby reducing the cost of feed. Further in-depth study may be required with breeding animals and the fattening pigs including cost- benefit analysis in order to provide strategic recommendations for pig producers in the country.</p> Tenzin Penjor Dorji Wangmo Gyembo Tsheten Pema Sherab Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 100 107 ASSESSMENT OF COST ON RAINBOW TROUT FINGERLING PRODUCTION IN BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/191 <p>This study aimed to determine the cost of production of rainbow trout fingerlings reared under Bhutanese climatic conditions and evaluate the economic aspects of Rainbow trout farming. The findings provide valuable insights into the cost analysis, serving as a reference for assessing farm efficiency, returns, and profitability. By establishing a production cost of Nu. 14/- per 25 grams fingerling, significantly lower than the market price of Nu. 25/-, this study highlights the potential for cost reduction and increased affordability of high-quality Rainbow trout seeds. This enables farmers to make informed decisions about their management practices, particularly in areas such as fish feed, to ensure the sustainability and profitability of their businesses. The study emphasizes the importance of optimizing production costs to enhance returns on investment, benefiting producers, farmers, and policy makers involved in the trout farming sector in Bhutan. &nbsp;</p> Bindiya Sharma Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 114 121 EFFICIENCY OF ARTIFICIAL INSEMINATION IN PIGS AT GOVERNMENT AND PRIVATE BREEDING FARMS IN BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/195 <p>The study assessed the conception rate of Artificial Insemination (AI) and other reproductive parameters in government and private pig breeding farms. The study also evaluated the performance efficiency of the AI services in both government and private pig breeding farms. In private pig breeding farms, the beneficiaries under Contract Piglet Breeding (CPB) farms and Big-Ticket Initiatives (BTI) were included. The breeding unit of National Piggery Research and Development Centre (NPiRDC) was the lone government breeding farm in the study. The fresh semen collected and processed/extended from the semen processing laboratory at NPiRDC was used for AI. A total of 87 numbers; (government farm = 48, private pig breeding farms = 39) of female pigs were inseminated with extended fresh semen (3 × 10<sup>9 </sup>motile sperm/dose in 100 ml semen collection tube) at 12, 24 and 36 hours after the onset of standing heat. The data were subjected to descriptive analysis and differences among the variables were measured using independent t-test. The study found that the conception rate in the government breeding farm (81.25%) was much better compared to private pig breeding farms (71.79%). Among the pigs impregnated with AI, there was no significant difference in terms of farrowing rate, litter size and stillbirth between government and private breeding farms. The study concludes that AI service in pig breeding is an efficient technology and can be widely adopted to boost pork production in the country.</p> <p><strong> </strong></p> Tenzin Penjor Sonam Penjor Tashi Phuntsho Pema Sherab Gyembo Tsheten Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 122 129 STRENGTHENING THE RESILIENCE OF TRANSHUMANT YAK PRODUCTION SYSTEM IN BHUTAN: A REVIEW https://ojs.moal.gov.bt/index.php/bjas/article/view/169 <p>Transhumant system of yak (<em>Bos grunniens</em>) farming plays a vital role in the livelihood of highland communities in Bhutan. Presence of yak-based transhumant systems in high altitude areas utilizes available natural resources in the area. Besides, the yak farming communities have a unique culture. However, an increasing number of households are said to leave yak farming. Therefore, this review was carried out to explore reasons for the decline and possible options for strengthening its resilience. The yak farming is under pressure from external factors such as socio-economic developments, policies and climatic conditions affecting forage and labour availability for herding yaks. Forage shortage for yaks is caused mainly due to overgrazing and grazing competition with other livestock species and wild ruminants. The other reasons for forage shortage are due to restriction on burning of shrubs around rangelands resulting to grazing land invasion by non-forage plant species. Labour shortages are caused due to increased access to alternative economic activities and modern education. Household members are increasingly involved in <em>Cordyceps</em> harvesting, tourism and other economic activities. Forage shortage and conservation policies had seemingly resulted in increased yak mortality due to accidents and wild predators. Therefore, to strengthen the resilience capacities of the system in regard to forage and labour availability, several options are possible. The options range from education and governmental policies for land management and development of infrastructures to better grazing management, including the reduction of yak herd size.</p> Gyembo Tsheten Thomas Demonty Stefanie Kucera Werner Zollitsch Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 33 47 YAK FROZEN SEMEN PRODUCTION AND CRYOPRESERVATION IN BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/193 <p>This is a short research communication to inform on yak semen collection and processing, successfully conducted under Bhutanese condition. Although the technology existed in yak rearing countries elsewhere, this is the first time it was successfully done in Bhutan. Two rounds of semen collection were attempted: one during non-breeding season on induced heat using exogenous hormones, and another on natural heat during the yak’s breeding season. The first attempt conducted during non-breeding season did not succeed mainly due to poor response of female yaks to heat inducing hormones and failure of yak bulls to mount female not manifesting heat. The second semen collection trial was timed during yak breeding season. Yak bulls were trained to mount in-heat females restrained in a chute. Several trials were conducted prior to the actual successful semen collection. There was a major technological breakthrough in yak semen processing in Bhutan wherein over 220 doses of yak frozen semen could be processed and cryopreserved. The semen was of acceptable standard with &gt;40% post thaw motility and had concentration of 27 million spermatozoa/dose when assessed after 24 hours. The scientific procedures and knowledge established including prior training of donor bulls to mount, timing of semen collection during breeding season and techniques to chill semen during transportation appropriate for Bhutanese farming environment is now understood. The procedures and techniques can further be improved and applied for quality semen production in Bhutan.</p> <p> </p> Dorji NB Tamang DB Rai Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 1 9 SOCIO-ECONOMIC BENEFITS OF THE CONTRACT FODDER SEED GROWERS IN BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/188 <p>The study assessed socio-economic benefits of the farmers from contract fodder seed production program in Bhutan. Data were collected from 30% of the total contract fodder seed growers from four districts i.e., Bumthang, Pemagatshel, Samtse and Sarpang. The findings indicated that the fodder production program has benefitted the contract fodder seed growers to enhance their income and livelihood status. Almost all respondents were satisfied with the supports provided by the Government; besides having derived financial benefits from the program. It was observed that the income generated from the sale of fodder seed were used for livelihood improvement such as housing, drinking water, sanitation and in procuring inputs for enhancing seed production. The seed production also shows a steady increment over the years. However, there is a need to strengthen further linkages between the National Development Centre for Animal Nutrition Program and CFSGs in imparting knowledge and dissemination of technology, besides continued regular incentive supports. The study concluded that sustainability of fodder production is dependent on awareness of the farmers, availability of seeds and market linkage for sale of fodder seed. To sustained fodder seed production by the seed grower groups, the NDCAN need to design an appropriate intervention and create an enabling environment, both forward and backward linkages with dairy farmers to upscale improved fodder production.</p> Pema Yangzom Wangchuk Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 48 54 UNDERSTANDING THE FISH FARMING CONSTRAINTS https://ojs.moal.gov.bt/index.php/bjas/article/view/192 <p>This case study was conducted to understand constraints to fish farming in Samdrupcholing Dungkhag. The technical staff of the Regional Centre for Aquaculture (RCA), Department of Livestock (DoL), Phuntshothang were used to collect data from all known fish farmers under Samdrupcholing Dungkhag. The study revealed that majority of the farmers (88.89%) were male, with larger proportion of age group (29.63%) are between 41-50 and 61-70 years of age. Majority (55.56%) of the fish farmers are illiterate while 51.85% of them have more than 11 years fish farming experience. Almost all (92.59%) the respondents are Hindu religion followers and farming (85.19) as primary occupation. Analysis of constraints in fish farming showed that unavailability of fish feed and pest/predators are the major constraints while water availability, technical knowledge of the farmers and inadequate capital were ranked as minor constraints deterring the fish farming in the region. Of the listed constraints, unavailability of fish feed, pest/predators, inadequate capital and water availability are more important because these constraints exist at severe to very severe level while technical knowledge and inadequate capital in constraints to severe level.</p> Dorji Tshering Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 74 80 INVESTIGATION OF PORCINE CIRCOVIRUS‐ASSOCIATED DISEASE (PCVAD) IN GOVERNMENT PIG BREEDING FARMS IN BHUTAN https://ojs.moal.gov.bt/index.php/bjas/article/view/167 <p>Porcine circovirus type 2 (PCV2) belonging to genus Circovirus is the primary causative agent of several syndromes collectively known as porcine circovirus‐associated disease (PCVAD). An investigative study was conducted on the prevalence of PCVAD following a report of various degrees of morbidity and mortality in targeted government pig farms (NNPBC, Yusipang, NPBC, Wangchutaba &amp; RPPBC, Lingmethang). Screening of sera samples conducted during September 2021 detected seroprevalence of PCV2 of 28/29 (96.5%) at RPPBC Lingmethang, 11/11(100%) at NNPBC Yusipang and 5/5 (100%) at NPBC Wangchutaba. From the same serum samples screened also detected seroprevalence of PRRSV as 7/29(24.1%) at RPBC Lingmethang, 1/11(9%) at NNPBC Yusipang indicating co-infection. However, from the clinical samples of NNPBC, Yusipang 5/10 (50%) tested positive to PCV2 through rtPCR during September 2021, whereas from the clinical samples of outbreak at RRPBC, Lingmethang during September 2022, 11/11(100%) sera tested positive in ELISA to PCV2 antibodies; 11/11(100%) of vaginal swab samples and 5/5(100%) of organ samples tested positive to PCV2 in PCR. All the clinical samples from RRPBC, Lingmethang tested positive to PCV2. As the prevalence of disease is quite evident, a strict biosecurity control measures at the farms should be implemented to stop further spread of the virus. Besides, vaccination of pigs like in other countries may have to be explored and adopted in these government farms if found feasible. Furthermore, a detailed study needs to be conducted in all the government and private pig farms with larger sample size to clearly understand the real status of the disease in the country for devising an appropriate intervention.</p> Nirmal Kumar Thapa Copyright (c) 2023 Bhutan Journal of Animal Science https://creativecommons.org/licenses/by/4.0 2023-03-31 2023-03-31 7 1 108 113