|Livestock Research for Rural Development 31 (10) 2019||LRRD Misssion||Guide for preparation of papers||LRRD Newsletter||
Citation of this paper
Creole cattle populations constitute an important reservoir of genes related to climate resilience and adaptation to harsh environments. During the last years, an unplanned crossbreeding process has threaten the genetic diversity of local Creole cattle populations in Bolivia, risking the conservation of valuable genes for the global animal genetic resources. Generation of reliable information about the production systems and management practices of local breeds, is a key first step for the development of conservation and breeding programs. With this purpose, open-ended and closed-ended questionnaires and interviews were performed with the participation of 81 smallholders from 11 communities of Pasorapa, Bolivia. Pasorapa Creole Cattle is a well-adapted breed to a xerophytic ecosystem, and a rearing system based in two stages, with cattle being released in the mountains for about 7 months across the year, and for the remaining time herded in the paddocks. Feeding strategies are based on crop residues and consumption of native plant species. High mortality rates are explained mainly by environmental factors such as predator attacks. Poor infrastructure, insufficient governmental support and deficient health management practices were found. Even though this cattle population is well adapted to cope with the challenging environmental conditions and management practices, more in depth studies are required to plan improvements on the implementation of the health scheme.
Keywords: herd structure, infrastructure, local breed, mortality, health management
Local breeds contribute across-breed genetic diversity to global animal genetic resources (Biscarini et al 2015). Small and well-adapted cattle populations have been a focus of attention because of their high adaptability to harsh environments and heat stress, as well because of their disease resistance and tolerance to parasites. These traits make them an important source of genetic variability to improve the response to climate change of temperate and highly productive breeds.
The first bovine individuals arrived on the second voyage of Christopher Columbus to America in 1493. These animals showed a high phenotypic diversity, which made their adaptation to different types of environments possible (De Alba 2011; Gautier and Naves 2011; Martinez et al 2012). The natural selection process led to the formation of ecotypes that are well adapted to harsh environments and which have been raised under mostly poor management strategies. An example of such ecotypes is the Creole cattle from Pasorapa. Until the development of this work, no previous deep information about this population was available.
Local cattle are the main source of income for smallholders in Pasorapa. Animals are reared for milk and beef production, and they are still used as draught power in the most remote communities. The last few years an uncontrolled crossbreeding process has threatened the genetic diversity and thereby possibly the conservation of genes responsible for resilience and tolerance in this population. In this scenario, a need for a conservation and breeding program for the Creole cattle in this region arises.
Animal breeding programs are dependent on the environmental conditions, the production system and the breeding objectives (Wapakhabulo 2016). Incomplete knowledge about the dynamic of a production system, herd structure and attitudes of farmers can lead to inconsistent genetic improvement programs (Gebretnsae et al 2017). In this study, we describe the main characteristics of the Creole cattle production system in Pasorapa, Bolivia, to generate information to be used for the development of conservation and breeding programs for this bovine population.
The study was carried out in the municipality of Pasorapa, Second Section of the Province Narciso Campero located in the southeasternmost part of the Department of Cochabamba in Bolivia. The altitude of Pasorapa ranges between 1200 and 2068 m.a.s.l. The average temperature is 15.5°C, being possible to have lower temperatures than 0°C and as higher as 33.9°C. Data were collected from 11 communities: La Aguada, Buena Vista, La Abra, Pasorapa (OTB Norte), Conchu Laguna, Robles, Ruda Pampa, Seibas, Tabacal, Toyota Baja and Zapallar.
Open-ended and closed-ended questionnaires were performed with 81 farmers distributed over all the 11 communities. The ownership of Creole cattle herds was the inclusion criteria to select respondent farmers. Snowball sampling was followed to identify more participants. As a first step, qualitative and quantitative information related to management, herd structure, feeding strategies and production system was collected from two different questionnaires during farm visits. As previous information about the system was not available, additional questions had to be included in the second questionnaire after the results from the first one were analyzed. A second step with face-to-face in-depth interviews following a semi-structured approach was carried out to a subset of 16 farmers identified as the most traditional Creole cattle breeders. This second step was performed to obtain qualitative additional data to understand the reasons behind rearing and management practices. During visits to farms and ranchland, observations of infrastructure, animal handling practices and vaccination methods were done.
During the visits, tours in the farms surroundings and the rangelands were done to observe feeding options of animals and eating behavior. Observations were documented as field notes, pictures and video recordings. During the first step of the study, visits to the farms were scheduled according to the vaccination program in Pasorapa. The purpose of this was to observe animals handling, vaccines storage and handling, and participation of farmers during immunization or deworming.
Questionnaires and interviews were performed in Spanish. Information from questionnaires was collated in different spreadsheets in Microsoft Excel. Recorded face-to-face interviews were transcribed to text. Qualitative data was analyzed using the software NVIVO 10. Basic descriptive statistics were calculated for quantitative data using Excel and R version 3.5.1. Copies of the questionnaires and semi-structured interviews are available upon request.
According to questionnaires, the rearing system is divided into two seasons per year. A Paddock Stage (dry season) between June and October and a Ranch Stage (rainy season) between November and June (Figure 1). Crop residues are used to feed animals during the Paddock Stage (Figure 2a). Throughout the Ranch Stage cattle spend most time browsing in the hills for food and water. During this time animals feed only on native pastures, shrubs and forage trees (Figure 2b). Black rocks of salt are available in the paddocks and across the ranch as mineral supplement for animals (Figure 3).
|Figure 1. Distribution of time cattle spend in the paddocks and in the ranch lands along the year|
According to the questionnaires the most common crops for farmers own consumption and used as forage for their cattle were maize, cultivated by 93% of the farmers, followed by oat (38%), sorghum (14%), and barley (5%). Wheat was mentioned as an important forage crop by 22% of the farmers in the communities of Conchu Laguna and Ruda Pampa. After harvest, cattle graze crop residues during the Paddock stage. Some farmers produce maize silage on a small scale.
|Figure 2a. Cattle feeding from crops residues during the Paddock stage|
|Figure 2b. Animals feeding of native plant species in the mountains during the Ranch Stage|
Calves are born during both the Paddock and the Ranch stages. They are mostly weaned between 4 and 8 months old. Male calves to be used as possible breeding bulls are allowed to continue suckling for one year.
|Figure 3. Black rock of salt as mineral supplement for animals in the pens|
Most of the visited farms had poor small no-grazing pens made of wood boards, trunks and bushes (Figure 4). Only 3 farms had wire fences delimiting only part of the area, creating smaller corrals to separate calves or young bulls. As pens have no roofs, animals are completely exposed to low and high temperatures or direct solar radiation. For this reason, pens are usually built around trees, which can be used to provide shade and to tie animals. No feed bunks were observed and water troughs were present only in some cases. None of the Creole cattle rearing farms had crush pens, neck clamps or squeeze chutes.
|Figure 4. Rustic paddocks infrastructure for Creole cattle in Pasorapa made of (from left to right) wood boards, trunks and bushes|
Water ponds called “atajados” were built in different places across ranches to provide water for animals. They can be for private or common use (Figure 5), and are filled by either rain water or water wagons. Plastic or rubber water tanks were found in almost all farms. The stored water was only for family’s use and crop irrigation during drought periods. Maize green forage was sometimes stored outside on surfaces built on the top of willows or a cactus species called Carapari, these structures are called “Calcheros”.
|Figure 5. Cattle drinking water from water ponds during the Ranch stage and the Paddock stage|
Herd size varied between the years due to mortality and high sale frequency during drought periods. Nevertheless, in most cases size did not exceed 100 heads of cattle per farm. Only one of the farmers declared owning 300 heads of cattle. Calf/cow ratios varied substantially between farms, with no apparent effect of community. 12% of farms showed a ratio of at least 1 calf per cow, 46% a ratio of 1 calf for every 2 cows, 26% of farms had a ratio of 1 calf for every 3 cows, and 14% showed a ratio of 1 calf for more than 5 cows. The lowest ratio was 1:16 found in one farm. Two landholders with herd sizes of 11 and 12 heads of cattle reported no calves.
Ratios between young bulls and breeding bulls also varied between farms. 19% of farms kept only breeding bulls (from 1 to 7) in the herd, 14% had no male, 23% had only one young bull possibly to become the breeding one, and 19% of the farms declared to have a ratio of 2 or more young bulls per breeding bull. Interviews revealed that all males without good characteristics for becoming a sire are sold before they reach 1.5 years of age. In some cases such individuals are castrated and used as draught power. Some farmers declared they get more profit from the sale of young bulls, which could explain the high values observed in some farms for this category.
Identification of animals was mainly based on coat color, shape and presence or absence of horns, age and dam recognition. Ear-tagging was only observed on purchased breeding bulls bought from different areas of the country like Santa Cruz or El Chaco. Hot iron branding and ear-notching were more commonly practiced by farmers during the second or third month of the year for the time of Carnival festivities. Cows selected for an additional molecular characterization study were identified with ear tags in the present study (Figure 6). Performance recording is not done, body weight is not measured at any stage of development and no pedigree information was available.
|Figure 6. Animal identified with an ear tag during data collection in this study|
Only one veterinarian belonging to the NGO “La Parroquia” offered health care services. Long distances to communities, limited road access and landslides can make it even more difficult to provide timely health assistance to animals. To counteract this, one famer from each community had been trained by the veterinarian to attend to the most common illnesses in animals. These Livestock Technical Assistants (LTAs), as they are called, were provided with basic medicines so they can get profit from sales. Most of the trained people have only primary school education level. Governmental institutions occasionally organized vaccination campaigns.
Data related to mortality were collected from our questionnaires. However, no farmer kept records about disease frequencies or mortality rates. The most frequent causes of cattle mortality, as disclosed by the farmers, are shown in figure 7. Among the environmental causes predator attacks, accidents and feed shortage were reported in higher frequency. Water scarcity had the lowest frequency, possibly because animals are sold before they die, therefore farmers do not identify this factor as a cause of mortality. However, the death of calves at birth during a drought period during the Ranch stage were mentioned during the interviews. In 2018, after a long and severe drought, interviewed farmers identified water scarcity as the main cause of livestock death.
In order of importance and frequency piroplasmosis, macurca, diarrhea, anthrax, rabies, arthritis and intoxication with stick insect (Pajuela) were mentioned. It is relevant to mention that the causative agent of the “macurca” disease is still unknown. Affected animals present leg paralysis during the early hours in the morning after the first rain of the season. Animals die because they cannot move to feed themselves. Cases are reported from when the rain season starts and cattle are already grazing in the hills. Piroplasmosis, anaplasmosis, foot rot during rainy season, posterior paralysis due to piroplasmosis, miscarriages due to trauma, retained placenta, weight loss due to parasites, and abdominal pain due to either gastrointestinal diseases or intoxication, were the most frequently diseases reported and treated by the local veterinarian.
|Figure 7. Mortality causes per year for Creole cattle in Pasorapa|
Plant poisoning is a recurrent disease mostly during drought periods. Photosensitization of unpigmented skin and white coated animals is a symptom caused by consumption of Heterophyllaea lycioides (Rusby) Sandwith. Affected cows develop ulcers on the skin and become blind.
The government institution SENASAG is in charge of executing and monitoring the vaccination program. Nevertheless, support from this entity is discontinuous and limited. Long distances and lack or poor condition of roads complicate deeper interventions.
Table 1 shows the current calendar for vaccinations and health management tasks. However, according to the local veterinarian, not all farmers implement all listed tasks or vaccinations mostly because of lack of money. According to questionnaires only 9% of farmers followed the vaccination schedule. Remaining interviewees (91%) vaccinated animals only against either rabies or anthrax, or immunize animals against both diseases but only once per year.
Pasorapa has been declared a Foot and Mouth Disease-free area. Despite of this, immunization against FMD is still scheduled in the calendar, but none of the farmers vaccinated against this disease (Figure 8). Immunization against Brucellosis was not included in the calendar. According to the veterinarian there were no reported cases of animals with this disease. Cases of retained placenta were explained as a consequence of undernourishment and accidents.
Immunization against Anthrax was done conventionally for three month old calves, while still in the paddocks. However, as deaths of one-month-old calves due to Anthrax have been reported, vaccination against this disease was performed to even younger calves of one month of age.
Vaccinations and deworming are performed by either the local veterinarian, LTAs or the farmers (Figure 9). Among 30 respondents 40% dewormed animals twice per year, while 60% did it only once per year. Deworming was usually done when cattle arrive in the paddocks and before they were released to the rangelands.
Welfare issues in livestock associated with extensive production systems include exposure to extreme weather conditions and limited medical assistance for sick or pregnant animals (Endres and Schwartzkopf-Genswein 2018). The highest mortality rates in Pasorapa herds are explained by predator attacks, accidents, such as falling down into ravines, and food and watershortages. Because of the poor infrastructure of paddocks, animals are exposed to extreme temperatures, parasites and predators during the Paddock, but especially during the Ranch stages. Proper medical assistance during calving is not always possible as farmers track animals in the hills only approximately twice per month, risking dam and calf survival when calving happens during the Ranch stage. More frequent surveillance would most likely also reduce the mortality due to “macurca” disease as recent experiences have shown that immediate treatment of paralyzed cows with medication to eliminate toxins and a treatment of tissue inflammation results in a complete recovery of animals.
Improvements related to infrastructure, water availability, forage production and pastures require investment, and the availability of hired help. According to our observations, infrastructure for cattle housing and management is still rudimentary in Pasorapa. Similar studies carried out in developing countries, stated the importance of improving infrastructure to ensure a long term sustainability of the systems (Ojango et al 2016).
Appropriate infrastructure would allow farmers start keeping records about pedigree information as well as productive and reproductive traits. A lack of record keeping likely prevents farmers from recognizing diseases and mortality causes (Hötzel et al 2014). Well worked recording schemes are a critical issue to establish a breeding program. They will also assist farmers to better understand improvements in productivity and the positive effects of changing management practices. On the other hand, strategies to minimize the effect of the exposure of animals to environmental risks and limited medical assistance are required to increase productivity. These strategies involve improvements in farms infrastructure.
Theoretically the optimum herd size is a function of the prevailing environmental condition, the ecosystem carrying capacity, the herd management practices and the use and distribution of resources (Akpa et al 2012). In the management system of Pasorapa, environmental conditions are highly variable and hence also variation in herd sizes. Variation in the number of animals and for instance cow/calf ratio due to mortality and sale frequency after drought periods is a factor to be considered in genetic improvement programs, given that selection intensity and genetic progress are influenced by the herd size and structure. Large differences in herd structures and production traits have been reported in pastoralist systems (Cossins and Upton 1988). This is explained by the wide variation between years and seasons that leads to large uncertainties in livestock productivity estimates for semi-arid areas (Upton 1989).
Herd characteristics provide information about productive performance (Wapakhabulo 2016). Sex and age ratios have been used to describe herd composition, herd productivity, status and demographic trends of ungulate populations (Bender 2006; Vetter and Arnold 2018). As Pasorapa cattle spend between 6 and 8 months grazing free in the hills with a minimum of management, age and sex ratios may produce interesting information. Low calf to cow ratios can be explained by a low adult animal mortality rate, low calving rate, high offtake rate of calves and a high calf mortality rate. Management practices and causes of mortality described in this article, support that a high calf mortality rate, possibly due to predator attacks and diseases, may explain the low calf to cow ratio obtained in almost half of the visited farms. On the other hand, the calf/cow ratio is also an indicator of relative fertility levels in a herd (Eugene 2017). Unfortunately, records of calving rates were not available to evaluate this argument.
Use of ratios can provide useful information to farmers such the maximum sustainable mortality rate for cows, heifers or calves in the following year. Culling rates go up during severe drought periods. Older cows are sold first, but heifers are sometimes also sold without proper planning. It is important then that farmers have a good idea about the minimum number of replacement heifers to be kept in the herd to not compromise productivity and breed conservation. Increased sale of animals without taking into account productivity, sex or age is a common practice in pastoralist systems in developing countries. In such systems, farmers are forced to sell large number of animals because of frequent droughts, financial pressure and food insecurity (Pavanello 2010; Mwanyumba et al 2015).
Because of management practices and lack of infrastructure, females start breeding before they are two years old. Changes in the age at first calving affect the herd composition. Since the age at first calving decreases, the number of replacement heifers decreases as well. Interviews revealed that some farmers still select a breeding bull from the same herd. This is especially important when considering that cows are kept in the herds as long as they have calves, which increases the possibility of relationship between animals. Molecular studies should be conducted in order to evaluate inbreeding levels (Jaitner et al 2003; Gwaza et al 2018). This will give relevant information on the structure of the Creole cattle population and the future options for the implementation of conservation schemes.
Location of communities, topography and accessibility by roads are perceived by Bolivian farmers as the main reasons for the low intervention of governmental institutions (Limon et al 2014). Livestock keepers from more distant communities in Pasorapa considered themselves neglected. Vaccination campaigns usually reach few animals from the more accessible and closest farms and communities. Landslides are very common during the rainy season. Some farmers and communities are in such cases accessible only by motorbike or horse. Training of LTAs is a good initiative to ensure basic medical assistance to animals and a reduction of cattle mortality in such communities.
Resistance to parasites in creole cattle populations has been reported before (De Alba 2011; Martínez et al 2012). The high frequency of piroplasmosis as mortality cause suggests the need for a deeper analysis, especially since the last few years an uncontrolled crossbreeding process has been taken place in this population. According to the interviewees, the frequency of this disease increased lately. The veterinarian explained during the interview that most frequently affected animals are those used for draught power or recently calved cows. Farmers explained this phenomenon as a consequence of drug resistance in parasites. But, a higher frequency of crossbreeding might be also a reason. Appropriate disease and medicine record books and molecular genetics studies would be needed to establish a potential relationship between crossbreeding and increased frequency of piroplasmosis.
Despite the perception of complete absence of brucellosis in Pasorapa, proper clinical and laboratory tests are not performed when cases of retained placenta appear. Lack of adequate equipment, chemicals and trained personnel need to be solved, in order to generate reliable records about prevalence and incidence of diseases in this area.
Vaccination against anthrax should be done before calves are three months old, followed by a second immunization 6 or 12 months after. Given that a higher percentage of farmers immunize against this disease only once per year, and that a high proportion of them do this during the Ranch season, the probability that not all calves are vaccinated in time is high. Considering the prevalence of anthrax in this area, booster shots after 6 months of the first dose would be recommended. The low income levels of farmers and lack of infrastructure might explain their carelessness in vaccination and deworming. It is also relevant that animals using communal water ponds either during the Paddock or the Ranch season, should be dewormed more frequently. Interviews revealed some cases in which farmers wait to deworm animals until they are in critical condition.
A poor infrastructure of paddocks, an insufficient governmental support, a deficient health management and a challenging rearing system for the animals were found in the Pasorapa Creole cattle system. However, this cattle population is well-adapted to cope with the challenges of the environment uncertainty and the rearing practices described in this study. More in depth studies are required to identify the reasons behind the management practices of farmers, and also to plan interventions to improve the adaptation and implementation of the health scheme. It is important to generate this information before any conservation and breeding plan is proposed. The genetic, cultural and economic value of this breed should motivate further studies to analyze this production system more deeply.
The authors want to thank all farmers from Pasorapa who participated in this study. A special thanks to Dr. Freddy Cabrera for his assistance and advising. Our gratitude with the Municipal Government of Pasorapa and also with Camila Rivera Mora, student from Universidad Mayor de San Simon, who participated in the acquisition of data. This study was financed by SIDA-Swedish International Development Cooperation Agency and a project financed by Development research and Swedish research links.
The authors declare they have no conflict of interest.
Informed consent was obtained from all individual participants included in the study.
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Received 2 July 2019; Accepted 9 September 2019; Published 2 October 2019
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