Conservation Herd Research Articles

Superovulatin Peformance and Embryo Recovery in South Anatolian Red Cows

South Anatolian Red (SAR) cattle which breeds from Mersin to Sanlıurfa with centered Kilis in the region of South Anatolia, is one of native breeds of Türkiye. The aim of this study is to evaluate the superovulator response and embryo recovery rates after the superovulation protocol applied to the SAR breed cattle.
 Fort this purpose, 10 donors were selected from the conservation herd in Eastern Mediterranean Agricultural Research Institute. FSH was performed to donors in decreasing doses twice daily over a 4 day period. Before uterine flushing, the ovaries were examined by ultrasound and the structures on them were recorded in order to determine the superovulation response. Each cornu uteri was flushed with foley catheters using a 3-way Y catheter. In the evaluation of embryo recovery, embryos were classified as transferable and non-transferable embryos . In South Anatolian Red cattle, the response to superovulation was found as average 7.8 corpus luteum and 2.8 anovulatory follicule for 10 donors which performed superovulation protocols. After uterine flushing, 5 UFOs, 3 non-transferable embryos and 2 transferable embryos were obtained from 10 animals.
 As a result, superovulation response and embryo recovery of SAR cattle was tried to be evaluated. In this study, although the superovulation response was good, the reason for the low embryo recovery rate may be due to the low reproductive performance in SAR cattle. And also, it has been concluded that the hormonal imbalance of these aggressive animals and the difficulties that occur during uterine flushing affect embryo recovery. It was thought that more studies should be done, different superovulation protocols should be tried and OPU technic should be evaluated in order to increase the rate of transferable embryos from SAR cattle. In addition, it was concluded that different techniques should be tried while performing uterine flushing procedures.

Linkage Disequilibrium, Haplotype Block Structures, Effective Population Size and Genome-Wide Signatures of Selection of Two Conservation Herds of the South African Nguni Cattle.

Simple SummaryKnowledge of linkage disequilibrium (LD), haplotypes blocks, and selective sweeps is important for effective application of genomics in breed characterization, improvement, and conservation, amongst other uses. The South African Nguni cattle breed is a Sanga breed that is well known for its ability to adapt to various environmental conditions such as harsh pedoclimatic and socio-economic conditions which exist in semiarid areas. Nguni cattle are characterized by many eco-types and research populations have been established in an effort to conserve the diversity within the breed by sampling in animals from different ecotypes into the herds. In this study, we calculated autosomal linkage disequilibrium, haplotype block structure, and screened for selection sweeps in two Nguni conservation herds of Bartlow Combine (n = 85) and Kokstad (n = 42), whose animals were genotyped on the Illumina High-Density Bovine SNP BeadChip®. The two herds were generally similar based on a number of genetic parameters. Overall, the study implied reduced genetic diversity in the two herds, calling for corrective measures to maintain the diversity of the South African Nguni cattle.The Nguni cattle of South Africa are a Sanga breed, characterized by many eco-types and research populations that have been established in an effort to conserve the diversity within the breed. The aim of this study was to investigate the overall genetic diversity as well as similarities and differences within and between two conservation herds of the South African Nguni Cattle. Mean LD (r2) estimates were 0.413 ± 0.219 for Bartlow Combine and 0.402 ± 0.209 for Kokstad. Genome-wide average LD (r2) decreased with increasing genetic marker distance for both populations from an average of 0.76 ± 0.28 and 0.77 ± 0.27 at 0–1 kb bin to 0.31 ± 0.13 and 0.32 ± 0.13 at 900–1000 kb bin in Bartlow Combine and Kokstad populations, respectively. Variation in LD levels across autosomes was observed in both populations. The results showed higher levels of LD than previously reported in Nguni field populations and other South African breeds, especially at shorter marker distances of less than 20 kb. A total number of 77,305 and 66,237 haplotype blocks covering a total of 1570.09 Mb (61.99% genome coverage) and 1367.42 Mb (53.96% genome coverage) were detected in Bartlow Combine and Kokstad populations, respectively. A total of 18,449 haploblocks were shared between the two populations while 58,856 and 47,788 haploblocks were unique to Bartlow Combine and Kokstad populations, respectively. Effective population size (Ne) results demonstrated a rapid decrease in Ne across generations for both Bartlow Combine and Kokstad conservation herds. Two complementary methods, integrated haplotype score (iHS) and Extend Haplotype Homozygosity Test (XP-EHH), were implemented in this study to detect the selection signatures in the two herds. A total of 553 and 166 selected regions were identified in Bartlow Combine and Kokstad populations, respectively. DAVID and GO terms analysis of the regions under selection reported genes/QTLs associated with fertility, carcass weight, coat colour, immune response, and eye area pigmentation. Some genes, such as HCAR1, GNAI1, PIK3R3, WNT3, RAB5A, BOLA-N (Class IB MHC Antigen QA-2-Related), BOLA (Class IB MHC Antigen QA-2-Related), and Rab-8B, etc., were found in regions under selection in this study. Overall, the study implied reduced genetic diversity in the two herds calling for corrective measures to maintain the diversity of the South African Nguni cattle. This study presented a comprehensive analysis of the genomic architecture of South African Nguni cattle populations, providing essential genetic information of utility in the management of conservation flocks.

The Composition of the Carcass, Physicochemical Properties, Texture and Microstructure of the Meat of D11 Dworka and P9 Pekin Ducks.

Simple SummaryThe production and consumption of duck meat in the world have a centuries-old tradition. Currently, China is the largest producer of duck meat. In Europe, the top producers of duck meat are France, Hungary and Poland. The aim of this study was to compare Pekin ducks (conservative strain P9) and Dworka (breeding strain D11) in terms of weight and percentage of gutted carcass components, basic chemical composition, physicochemical properties of breast and leg meat as well as texture and microstructure of breast meat. Significant differentiation (p < 0.05) for the genotype was found in terms of carcass weight, the content of most chemical components, some physicochemical features of the pectoral muscles and legs, as well as the thickness of connective tissue, springiness and WB (Warner–Bratzler) shear force m. pectoralis major. These differences were mainly due to the different purposes of the ducks. Dworka ducks from the D11 strain are being improved in terms of their functional characteristics (breeding strain), while Pekin ducks from the P9 strain have been kept in Poland as a conservation herd (without breeding selection) for several decades.The aim of the study was to determine the effects of genotype and sex on carcass composition and selected meat quality parameters of Dworka and Pekin ducks after two reproductive seasons. The research material consisted of 24 carcasses of Dworka ducks (breeding strain D11) and 24 carcasses of Pekin ducks from the herd of genetic resources (French Pekin, strain P-9). After cooling the carcasses (18 h, 2 °C), the pH values and electrical conductivity of the pectoral and leg muscles were determined, and then the carcass was dissected using a simplified method. After dissection, the pectoral and leg muscles were sampled for quality characteristics assessment. The Dworka ducks from breeding strain D11 compared to Pekin duck from conservative strain P9 were characterized by significantly (p < 0.05) higher carcass weight, protein and salt content, thermal drip, yellowness, thickness of perymisium and endomysium and lower water content of the pectoral muscle. Dworka ducks were also characterized by higher protein, salt and collagen content and higher electrical conductivity (EC24) of leg muscles than Pekin ducks. Regardless of genotype, male ducks had a higher gutted carcass weight with neck, salt content, muscle fiber cross-sectional area, fiber perimeter and diameters of pectoral muscle, and also higher protein and collagen, and lower fat content, pH24 and electrical conductivity of leg muscles. The genotype by sex interaction was significant (p < 0.05) for water, protein, fat content, perimisium thickness, cohesiveness, springiness of the pectoral major muscle, and for water content and protein of the leg muscles. The results obtained in this study demonstrate the effects of genotype and sex on the nutritional value and some technological parameters of duck meat. The studied ducks after two reproductive seasons satisfactorily meet the requirements of duck meat for consumers and duck meat processing plants.

Genetic variation of the mitochondrial DNA control region across plains bison herds in USA and Canada

Once numbering in the tens of millions, bison (Bison bison) have faced a broad range of challenges over the past century, including genetic impacts from the population bottleneck in the 1800s, and significant loss and fragmentation of habitat resulting in little opportunity for population growth on remaining small, geographically isolated reserves. To identify best practices for bison stewardship against this backdrop, managers must understand the genetic composition of existing conservation herds. This study characterized 14 plains bison (Bison bison bison) herds managed by the U.S. Department of Interior and Parks Canada Agency based on complete mtDNA control region sequences. Among 209 bison, we detected 11 major mtDNA control region haplotypes based on nucleotide substitutions and 23 sub-haplotypes where indels are considered. We determined matrilineal relationships between the herds and compared our genetic findings to historic records. The recent common ancestry of modern bison deriving from small, scattered groups combined with gene flow through foundation and translocation events between herds during the last 100 years, is reflected in Fst value (0.21), haplotype (0.48 ± 0.04) and nucleotide (0.004 ± 0.002) diversities, and mean number of pairwise differences (3.38 ± 1.74). Genetic diversity was distributed unevenly among herds, with 21.41% of genetic variation observed between herds. Median joining network, together with trends in the Tajima's D and Fs tests, revealed two patterns in the recent evolution of mtDNA sequences in bison: mutational process has generated diversity with a Hap 1 haplotype epicenter, and missed mtDNA haplotypes exist in the network due to bottleneck, loss through management practices, or incomplete sampling of specimens across conservation herds. This work significantly expands characterization of the genetic diversity among bison conservation herds, providing additional decision support for managers considering restoring gene flow to achieve long-term species viability.

A Behavioral Index for Assessing Bison Stress Level during Handling and Demographic Predictors of Stress Response

ABSTRACT There are an estimated half-a-million Plains Bison (Bison bison) present in North America in commercial and conservation herds. Most bison are rounded up and “worked” annually for parasite control, veterinarian attention, and processing, making it important to understand the impacts of these operations. Research indicates bison generally experience higher levels of stress than cattle during similar handling processes. However, most methods for assessing stress-level during working are invasive, increase handling time, and paradoxically increase stress levels. We designed a behavioral index to assess bison stress level during handling and used it to evaluate various predictors of stress response in a semi-wild bison herd. We examined how sex, age, herd of origin, previous experience, calf rearing, and body condition influenced bison stress response during working operations from 2015 to 2017. Our results indicate that stress level decreased with age and previous experience being worked through a particular facility. Additionally, herd of origin influenced stress level, indicating that stress response may have a genetic or epigenetic component. Our study provides an easily applicable tool for monitoring bison stress levels.

De novo assembly and annotation of the North American bison (Bison bison) reference genome and subsequent variant identification.

Genomic tools have improved the ability to manage bison populations and enhanced efforts to conserve this iconic species. These tools have been particularly useful for detecting introgression of cattle genome within bison herds but are limited by the need to use the cattle genome as a surrogate for mapping reads. This complicates efforts to distinguish the species of origin of chromosomal segments in individual bison at the genomic level. An assembly (Bison_UMD1.0) based on 75X genome coverage by Illumina and 454 reads was generated using the MaSuRCA assembler, generating a 2.81 Gigbases de novo reference genome from American bison. Comparison of bison and domestic cattle references identified 28443364 single nucleotide variants and 2627645 insertions/deletions distinguishing the species. Sequence alignment of an additional 12 modern bison samples and two historic bison samples to domestic cattle and bison references provides a dataset of genomic variants defining the different species and within-species variation. This first annotated draft assembly represents a resource for the management and conservation of bison, as well as a means to study the effects on the genome of interspecies hybridization. The comparisons of historical bison sequences with the new bison reference identified genomic differences between modern and pre-population bottleneck bison. The results support the application of genomics to enhance future research on disease, the establishment of satellite conservation herds and insight into bison and cattle speciation. The first genome assembly for bison and dataset provides a foundation that can be built upon as genetic technologies improve over the years.

Activity and Overlap Among Birds and Mammals Scavenging A Bison Carcass in Shortgrass Prairie

Bison serve as keystone species in prairie ecosystems of North America, yet few studies have evaluated the effects of bison carcasses on other animals. To determine which species forage on bison carcasses and whether such carcasses catalyze intraspecific and interspecific interactions, we used wildlife cameras to observe scavenger visits and activity over a 6-wk period following the death of an adult female bison from a conservation herd in northern Colorado. We captured more than 45 000 photos of avian and mammalian scavengers. Photos most often included coyote (51% of photos) and common raven (50%), followed by black-billed magpie (14%) and golden eagle (0.11%). Most photos (86%) captured individuals of the same species (intraspecific activity) visiting the carcass, while 14% had two or more different species (interspecific activity) at the carcass simultaneously. The species most often photographed together included the common raven and black-billed magpie (64%), followed by coyote and black-billed magpie (25%) and coyote and common raven (7%). Less than 1% of photos captured dominance behaviors among individuals. Our study demonstrates that bison carcasses have the potential to provide key food resources in the winter for shortgrass prairie animals. The role of bison carcasses in supporting grassland animal communities is likely to become increasingly important as efforts gain momentum to restore bison across their historic range in North America.

Genetic Polymorphism of β-Casein Gene in Polish Red Cattle-Preliminary Study of A1 and A2 Frequency in Genetic Conservation Herd.

Simple SummaryCurrently, milk and dairy products are considered nutritious foods because they contain bioactive constituents. However, in some cases, milk consumption might cause health-related issues, such as allergic reactions. Among all of the proteins present in milk, caseins deserve special attention. A genetic variant called β-casein is recognized as a potential cause of some health implications. However, although milk protein characteristics have been widely covered, a significant majority of published research focus on one cattle breed: Holstein There are numerous local breeds that have not been widely analyzed to date. One such breed is a dual-purpose breed called Polish Red.Although there is growing interest in Red cow’s milk in Poland, to date there are few reports investigating the characteristics of milk components in the studied population. Particular emphasis on milk proteins is advised, since β-casein is a source of bioactive peptides named β-casomorphins. β-casomorphin 7, which originates mostly from β-casein variants A1, may be a significant risk factor in human ischemic heart disease, arteriosclerosis, type I diabetes, sudden infant death syndrome, and autism. The aim of the present study was to identify CSN2 polymorphism gene in exon 7 using the genomic sequence from GenBank (M55158), g.8101C>A, (codon 67). Blood samples were collected from 201 Polish Red cattle (24 males and 177 females). The genotype of β-casein was determined using PCR-ACRS. The frequency of β-casein A2 in Polish Red population was 0.47. β-casein A2 frequency in Polish Red bulls and in cows was 0.58 and 0.37, respectively.

Performance Traits of Puławska Pigs Depending on Polymorphism in the RYR1 Gene (C.1843C&gt;T)

Abstract The objective of the study was to determine the relationship between polymorphism in the RYR1 gene (rs344435545) and on-farm test results (fattening, slaughter and reproductive traits) of pigs maintained in conservation herds. the experiment covered 76 boars and 291 gilts kept in 33 herds. animals aged 150–210 days were weighed and P2 and P4 backfat thickness as well as P4 loin muscle depth (P4m) were measured with an ultrasonic device. standardised daily gain (g/day) of the animals and carcass meat percentage (%) were determined. the following reproductive traits of sows were also collected: number of teats, age at first farrowing, dates of next farrowing, number of piglets born alive and weaned at 21 days of age. Hair roots were sampled from the gilts, sows and boars to determine the RYR1 gene polymorphism. it was found that only 3% of the animals in the analysed population had TT genotypes, whereas 28.34% were heterozygous (CT). this polymorphism (CT) was carried by 28.34% of the animals. when analysing the effect of this polymorphism on fattening and slaughter traits in live animals, it was found that sows with TT genotype, compared to the others, were characterised by higher backfat thickness only (P≤0.05). In the boars with CC and CT genotypes, no significant differences were noted between the values of the analysed traits. for reproductive traits of the sows, it was observed that females with TT genotype weaned more piglets until 21 days of age (P≤0.05).

High society: behavioral patterns as a feedback loop to social structure in Plains bison (Bison bison bison)

Social organization as a topic has wide application often conserved across lineages and can lead to complex cultures, yet it is still not well understood in many taxa. We observed American bison (Bison bison) to investigate the interactions of hierarchy and behavior to elucidate patterns of social organization. Bison are highly visible animals that live in relatively accessible grasslands, and most are in semi-wild conservation herds that allows for access to low-stress observation and physiological exams. We observed behaviors in a semi-wild, reintroduced herd of 53 bison in a 140-ha prairie from April to October 2015 (165 h of observation). After establishing a linear hierarchy, we categorized individuals of each sex as high, mid-, or low ranking and then evaluated behavioral trends across rank and sex. We found that high ranking males constantly defended their linear positions and focused breeding efforts on the females with the highest productivity, consistent with disruptive sex characteristics. Intra-rank conflict focused on linear positioning likely causes the volatility in male bison hierarchy and stress of domination. Female bison, however, tend to suppress the lowest class, which likely drives their hierarchy’s stability and stress of subordination. Our results show that male and female bison are impacted differently by their social rankings and show that individual aggressive actions may provide feedback loops to their social organization.

Diversidade genética em caprino Marota e manejo genético para rebanhos de conservação

Objetivou-se avaliar a diversidade genética em rebanhos de caprinos Marota e verificar o impacto do uso de marcadores moleculares no manejo genético em rebanho de conservação. Utilizando-se Chip SNP caprino 50K genotipou-se 76 animais do rebanho de conservação institucional e 10 animais de um rebanho particular. Avaliou-se a dispersão dos animais por Análise de Componentes Principais (PCA) e em dendograma. Simulou-se acasalamentos entre animais que apresentaram maior distância no dendograma e menor coeficiente de consanguinidade (FIS) (Manejo I) para verificar a eficiência desse manejo, em relação à ocorrência de acasalamentos ao acaso (Manejo II). Valores altos de heterozigosidade observada (Ho) e esperada (He) nos animais adultos (Ho=0,372±0,005 e He=0,405±0,007) e nas crias (Ho=0,359±0,012 e He=0,374 ±0,028) e média do FIS igual a 6,4% indicam baixo risco de perda de genes no rebanho institucional. O rebanho particular também apresentou variabilidade genética (Ho=0,374 e He=0,498), porém com maior risco em relação à endogamia (FIS= 22,7%). A PCA indicou semelhança genética entre os rebanhos. A simulação de 10 pares de acasalamentos de cada reprodutor indicou que a média do coeficiente de consanguinidade dos casais formados de acordo com o Manejo I, foi estatisticamente inferior à média dos pares acasalantes formados de acordo com o Manejo II. Concluiu-se que existe variabilidade genética nos rebanhos analisados, porém com indício de consanguinidade; e que em rebanhos pequenos nos quais a reposição é feita com animais do próprio rebanho, a definição de acasalamentos com base em critérios genéticos, é opção para controle de consanguinidade.

Population genomics and gene introgression in goat herds naturally adapted to Brazil

The aim of this study was to apply the Illumina 50 K goat SNP Chip to analyse population genomic structure in two herds of Marota goats in the State of Piaui, one private and the other an official conservation herd, and to investigate evidence of genetic erosion in these herds caused by the Anglo-Nubian goat. To that end, 86 Marota and 10 Anglo-Nubian animals were genotyped. Genetic diversity was analysed by comparing minor allele frequency (MAF) in the herds. Population structure and genetic differentiation were evaluated using a Bayesian approach, principal component analysis (PCA) and the fixation index (FST). High genetic differentiation (FST = 0.16) was seen in the Marota population in relation to the Anglo-Nubian. The private herd shared a greater number of fixed SNPs with the herd of Anglo-Nubians (1024) than did the conservation herd (741). The results of the PCA, together with those from the analysis carried out using the Structure software, showed the presence of Anglo-Nubian genes in the Marota herds. It can therefore be concluded that the high level of polymorphism and high genetic differentiation between Marota and Anglo-Nubian goats characterise these animals as a source of genetic diversity for goat farming in the region; the Illumina 50 K goat SNP Chip is efficient in population structure analysis in Marota goats; microarray technology, analysis using the Structure software, and Principal Component Analysis complement each other in expanding the ability to detect gene introgression in small populations; there is evidence of the introgression of Anglo-Nubian genes in the herds of Marota goats under analysis.

High species diversity of trichostrongyle parasite communities within and between Western Canadian commercial and conservation bison herds revealed by nemabiome metabarcoding

BackgroundMany trichostrongylid nematode species are reported to infect bison, some of which are major causes of disase and production loss in North American bison herds. However, there is little information on the species distribution and relative abundance of these parasites in either commercial or conservation herds. This is largely because trichostrongylid nematode species cannot be distinguished by visual microscopic examination of eggs present in feces. Consequently, we have applied ITS2 rDNA nemabiome metabarcoding to describe the trichostrongyle parasite species diversity in 58 bison production groups derived from 38 commercial North American plains bison (Bison bison bison) herds from across western Canada, and two bison conservation herds located in Elk Island National Park (EINP) [plains bison and wood bison (Bison bison athabascae)] and one in Grasslands National Park (GNP) (plains bison).ResultsWe report much higher infection intensities and parasite species diversity in commercial bison herds than previously reported in beef cattle herds grazing similar latitudes. Predominant trichostrongyle parasite species in western Canadian commercial bison herds are those commonly associated with Canadian cattle, with Ostertagia ostertagi being the most abundant followed by Cooperia oncophora. Combined with high fecal egg counts in many herds, this is consistent with significant clinical and production-limiting gastrointestinal parasitism in western Canadian bison herds. However, Haemonchus placei was the most abundant species in five of the production groups. This is both surprising and important, as this highly pathogenic blood-feeding parasite has not been reported at such abundance, in any livestock species, at such northerly latitudes. The presence of Trichostrongylus axei as the most abundant parasite in four herds is also unusual, relative to cattle. There were striking differences in parasite communities between the EINP and commercial bison herds. Most notably, Orloffia bisonis was the predominant species in the wood bison herd despite being found at only low levels in all other herds surveyed.ConclusionsThis study represents the most comprehensive description of parasite communities in North American bison to date and illustrates the power of deep amplicon sequencing as a tool to study species diversity in gastrointestinal nematode communities.

Pedigree‐based genetic management improves bison conservation

ABSTRACTOverhunting and widespread land use change nearly caused the extinction of North American bison (Bison bison) by the late 1800s. Recovery efforts focused on preserving the remaining individuals and establishing federally managed conservation herds to build more sustainable populations. Today, bison in conservation herds are maintained in small, isolated herds that are managed through an annual or biannual cull of individuals to maintain target population sizes. We assessed alternative culling strategies for maintaining genetic variation over the long term in managed wild bison herds. Our objective was to compare a strategy modeled after a United States Fish and Wildlife Service strategy (all‐allele conservation culling strategy [AAC]) to a pedigree‐based mean kinship strategy (MK) and to a Random strategy that does not incorporate genetic data and is used to manage some conservation herds. We built an individual‐based model, parameterized in accordance with bison biology, to compare these culling strategies in 2 federally managed conservation herds at the Fort Niobrara National Wildlife Refuge (FTN herd) and the National Bison Range (NBR herd). Our MK strategy retained more genetic variation and slowed the accumulation of inbreeding relative to the AAC or Random strategies, and these findings were consistent across wild bison herds with different founding sizes and current genetic diversity. These findings extend previous work demonstrating the utility of pedigree‐based management strategies in captive and wild population management, and show that such strategies maximize the retention of genome‐wide variation in contemporary bison herds. The modeling approach used in this study was useful for assessing outcomes prior to implementation, and the specific models developed for this study can be easily adapted to other managed wildlife species. © 2018 The Wildlife Society.

Comparison of Genetic Diversity between the Ex-Situ Conservation Herd and Smallholders of Turkish Grey Cattle

Comparison of Genetic Diversity between the Ex-Situ Conservation Herd and Smallholders of Turkish Grey Cattle

Effect of maize DDGS addition on carcass and meat quality of lambs of native sheep breed

ABSTRACTThe aim of the study was to characterize carcass and meat quality of lambs of native sheep breed, which were fed a diet containing maize dried distiller’s grains with solubles (DDGS). The experiment involved 20 ram lambs of the native sheep breed Polish Heath Sheep (Wrzosówka sheep), which were selected from a conservation herd. The lambs received meadow hay and straw ad libitum as well as about 0.4 kg of concentrate per animal. The control group (C) received a standard diet based on cereal components and soybean meal, and in the experimental group (D), soybean meal and part of barley and wheat were replaced with DDGS (the addition of 45% DDGS to the lamb concentrates). The fattening was carried out for 60 days (up to 8 months of age). The diet had no effect on carcass quality, proportion of cuts, basic chemical composition of the meat and cholesterol content. The intramuscular fat of lambs fed the DDGS diet had a higher proportion of linoleic acid (C18:2 n-6) and conjugated linoleic acid, and a lower proportion of linolenic acid (C18:3 n-3), which had a negative effect on the polyunsaturated fatty acids n-6:n-3 ratio in the intramuscular fat. The addition of DDGS to the diet had a beneficial effect on the sensory properties of lamb meat, in particular its taste.

Caracterización morfológica de un rebaño de conservación de cabras criollas en Zacatecas, México

El objetivo fue identificar cabras de la raza Blanca Celtibérica en un hato de conservación en Zacatecas, México, mediante una caracterización fenotípica. Se utilizaron 81 cabras divididas en dos grupos, hembras mayores a un año (n=61) y menores al año (n=20). Se tomaron 8 características cualitativas y 15 cuantitativas. Se realizó análisis de conglomerados jerárquico y discriminante mediante el paquete estadístico SAS. El agrupamiento de hembras mayores al año fueron seis grupos con diferencias multivariadas (P

Birth-site selection and timing of births in American bison: effects of habitat and proximity to anthropogenic features

Context Human activities can affect habitat selection by ungulates during parturition. Minimising human–wildlife conflicts during the birthing period can be critical in national and state parks that receive high numbers of human visitors. American bison (Bison bison) are an iconic species in North America, and many conservation herds of bison occupy national and state parks and wildlife refuges. Aims We investigated timing of births and birth-site selection of bison on Antelope Island State Park, Utah, at multiple spatial scales to determine the relative influence of surrounding vegetation, topography and distance to anthropogenic features (i.e. trails, roads or structures) on selection of birthing habitat. Methods We used vaginal implant transmitters to determine timing of births and to identify birth sites of bison. We used logistic regression within a model-selection framework to differentiate between birth sites and random locations, based on potential explanatory variables. We then used model-averaged coefficients to produce and project a GIS model of birthing habitat onto Antelope Island. Key results During 2010 and 2011, we quantified variables surrounding 35 birth sites and 101 random sites. Variables in top models of birth-site selection for bison included landscape curvature and elevation, averaged at a 500-m radius around birth sites, as well as distance to nearest trails, roads or structures. Five-fold cross validation (rho = 0.89; P &lt; 0.05) indicated that these variables successfully predicted birth sites of bison in our study area; 80% of 41 births occurred in April (range = March 22 to May 20). Conclusions Bison selected areas for birthing with concave topography and increased elevation that were away from trails, roads or structures. Implications Our GIS model of birthing habitat, and data concerning timing of births, provide a map of high-probability birthing areas and a time of year at which human access could be limited to reduce disturbance from recreational activity. This approach could aid managers in minimising conflict between recreationists and parturient bison in other national and state parks and wildlife refuges.

Livestock Management for Coexistence with Large Carnivores, Healthy Land And Productive Ranches: A Viewpoint

I proceed from 3 assumptions: (1) Natural selection is necessary to maintain wild bison (Bison bison). (2) We don’t leave bison to future generations; we leave the bison genome. (3) Wildness is the opposite, in a continuum, from domestication. South of Canada, more than 200,000 bison are being domesticated in about 4500 private, commercial herds. In contrast, there are about 44 conservation herds owned by government agencies, the Nature Conservancy and American Prairie Reserve. In these conservation herds, natural selection is weakened or replaced by synergistic actions of (1) cattle-gene introgression; (2) founder effects; (3) inbreeding; (4) genetic drift; and (5) artificial selection. I review the prevalence of 12 management practices diminishing natural selection in these conservation herds, and promote a broader understanding and appreciation of the needs and values of wildness in American bison.

Heirloom genomes and bison conservation American Plains Bison Rewilding an Icon James A. Bailey Farcountry, 2013. 258 pp.

Heirloom genomes and bison conservation <b>American Plains Bison</b> Rewilding an Icon <i>James A. Bailey</i> Farcountry, 2013. 258 pp.