Genetische Analyse der Population des Hinterwälder Rindes

Short communication: Lethal mutations in Vorderwald cattle through Montbéliarde incrossings

The paper examines development of Czech agriculture through profitability of the 10 chosen most important commodities (wheat, barley, rapeseed, sugar beet, potatoes, dairy cows – milk, cattle fattening, suckler cows, pigs fattening, poultry – fattening broilers) in the time horizon 2002–2006. The aim of the paper is to give an objective information about the influence of agrarian policy on the development of agricultural commodities, especially with reference to the comparison of changes in the pre-accession (period I = 2002–2003) and in the after-accession of the CR to the EU (period II = 2004–2006). This deals with the economic position of Czech producers related to the most considerable commodities of Czech agriculture through 2 indicators, profitability without supports (R–S) and profitability with supports (R+S). There was proved that profitability R+S in the period I was positive for most plant commodities while it was negative for most animal commodities. In connection with the membership of the CR in the EU, agricultural supports significantly increased for nearly all commodities as the consequence of applying the Common Agricultural Policy (CAP) on Czech agriculture. Therefore, there were monitored in the period II important positive changes of the indicator R+S for most commodities. For the average of the Czech Republic, there were obtained the following values of R+S in the period I, resp. period II: wheat 2.6%, resp. 24.9%, barley 27.7%, resp. 39.8%, rapeseed –18.0%, resp. 23.4%, sugar beet 9.1%, resp. 41.4%, potatoes 10.5%, resp. 2.5% (the only one case of decrease), milk 2.1%, resp. 8.5%, fattening cattle –14.6%, resp. –3.6%, suckler cows –8.8%, resp. 19.7%, fattening pigs –5.5%, resp. –1.2%, fattening broilers –2.9%, resp. 0.1%.

Genetic diversity of a nucleus flock of Malpura sheep through pedigree analyses

This study aimed to investigate the lactation curve properties of primiparous and multiparous Barrosã cows, using two different milking systems. A data set with 2518 daily milk yields of 15 primiparous (107 test day records by lactation) and 11 multiparous (83 test day records by lactation) cows was individually fitted with the Wood’s model by the application of a non linear procedure. Milk yield measurements were recorded using a weigh-suckle-weigh technique in half of the cows and the remaining cows were handmilked. Average daily milk yield of primiparous and multiparous suckled cows were 4.9 and 5.2 kg, respectively, while correspondent scores on milked cows were lower (2.4 and 3.0 kg). All 26 fitted lactations followed the typical curve shape with high goodness of fit. Analysis performed on Wood’s parameters indicated that milked cows have a peak yield of 3.5 and 4.6 kg reached at lactation day 23 and 16, for primiparous and multiparous, respectively. On the other hand, suckled cows reached later (56–63 d) their peak of lactation and the peak yield (5.3–5.7 kg) was greater than milked cows. The absence of the calf and the cow’s difficulty in adapting to the handmilking can explain differences between milked and suckled cows. Barrosã cows, in their traditional production system, have lactation yields of 805 and 843 kg in parities 1 and 2, respectively.

The objective of this study was to use pedigree analysis to evaluate the population structure and genetic variability of the Mazandaran native fowls in Iran by quantifying the pedigree completeness index, effective population size, genetic diversity, inbreeding level, and individual increase in inbreeding. The pedigree completeness analysis showed 3.31 full, 10.19 maximum, and 6.30 equivalent generations. The effective number of founders (f e) was 131, representing 5% of the potential number of founders. The effective number of ancestors (f a) was 81, and the genetic contribution of the 37 most influent ancestors explained 50% of the genetic variability in the population. The ratio f e/f a (effective number of founders/effective number of ancestors), which expresses the effect of population bottlenecks, was 1.62. The inbreeding coefficient increased over generations and the average was 1.93%. The average relatedness coefficient between individuals of the population was estimated to be 2.59%. The effective population size, based on the number of full generations, was 56. Family size analysis showed that fewer males than females were used, resulting in the observed levels of inbreeding. Average inbreeding coefficient in the Mazandaran native fowls can be regarded to be below critical levels. However, considering the relationship coefficients of individuals is recommended to aid maintaining genetic diversity of Mazandaran native fowls.

Population structure and effect of inbreeding on lamb growth in Bharat Merino sheep

The aim of this paper was to analyse alternatives of Pinzgau breeding program. Alternatives were optimised for genetic gain of selection index composed of parameters of milk efficiency traits and increase in inbreeding per generation. A scheme using the mating of 70% old proven sires led to a lower increase in inbreeding per generation from 0.248% to 1.903% than a young sires scheme with 0.313–2.177% or 0.303–2.18% without MOET when 2, 5, 10 and 20 proven sires were used in the population. Schemes using 70% mating of young sires resulted in a shorter generation interval of 3.46 years in comparison with proven sires scheme with 4.06 years. Young sires breeding program yielded lower genetic gain from 420.1 SKK per year when 20 proven sires were used to 578.44 SKK per year when 2 proven bulls were selected in the population. Proven sires breeding program led to higher genetic gain from 400.17 SKK (with 20 proven bulls) to 629.72 SKK (2 proven bulls). In a group with 20 proven bulls young sires breeding program with MOET resulted in genetic gain 466.38 SKK comparable to young sires breeding program without MOET with 10 proven sires. In groups with 10 or 5 proven bulls this alternative led to the highest genetic gain 515.45 SKK and 565.25 SKK, respectively. A group with 2 proven bulls in MOET scheme achieved similar genetic gain (629.14 SKK) like the proven sires scheme.  

BackgroundGeographical and temporal diffusion patterns of a human pandemic due to Swine Origin Influenza Virus (S-OIV) remain uncertain. The extent to which national and international pandemic preparedness plans and control strategies can slow or stop the process is not known. However, despite preparedness efforts, it appears that, particularly in the USA, Mexico, Canada and the UK, local chains of virus transmission can sustain autonomous dynamics which may lead to the next pandemic. Forecasts of influenza experts usually rely on information related to new circulating strains.MethodsWe attempted to quantify the possible spread of the pandemic across a network of 52 major cities and to predict the effect of vaccination against the pandemic strain, if available. Predictions are based on simulations from a stochastic SEIR model. Parameters used in the simulations are set to values consistent with recent estimations from the outbreak in Mexico.ResultsWe show that a two-wave pandemic dynamic may be observed in Southern hemisphere because of seasonal constraints for a maximum value of the basic reproductive number (R0, max) within a city equal to 1.5 and a mean generation interval (GI) of 2 days. In this case and in the absence of vaccination, attack rates may reach 46% when considering a completely susceptible population. More severe scenarios characterized by higher values of R0, max (2.2) and GI (3.1) yield an attack rate of 77%. By extrapolation, we find that mass vaccination in all countries (i.e. up to 50% of the population) implemented 6 months after the start of the pandemic may reduce the cumulative number of cases by 91% in the case of the low transmissible strain (R0, max = 1.5). This relative reduction is only 44% for R0, max = 2.2 since most of the cases occur in the first 6 months and so before the vaccination campaign.ConclusionAlthough uncertainties remain about the epidemiological and clinical characteristics of the new influenza strain, this study provides the first analysis of the potential spread of the pandemic and first assessment of the impact of different immunization strategies.

Pedigree analysis of Iran-Black sheep and inbreeding effects on growth and reproduction traits

The Nilagiri sheep is a dual utility (fine wool and meat), native to the Nilagiri hills of Tamil Nadu. It is known for its adaptability to high altitude and low input system of rearing. At present, this breed is endangered with less than a thousand numbers existing, of which about 50 percent is maintained at Sheep Breeding Research Station, Sandynallah. Efforts are on to conserve the breed in-situ. Generation interval (GI), pedigree completeness level, inbreeding coefficient (F), average relatedness (AR), effective population size (Ne), and effective number of founders (fe) and ancestors (fa) were studied for the breed. Pedigree analysis was carried out using data available at the research station on 5 051 animals from 1965 onwards using ENDOG ver. 4.8. Higher values of pedigree completeness (more than 80 percent for 5th generation), balance in percent of ancestors between sire and dam pathways and higher equivalent complete generations (7.12) for the reference population were indicative of the depth in pedigree. The GI, F, and AR were 3.36 years, 2.17 and 3.45 percent, respectively. Ne based on maximum number of generations and individual increase in inbreeding was 298.83 and 97.25, respectively. fe and fa were 59 and 41, respectively, for the reference population. F was far from critical values of inbreeding and fe/fa ratio indicated absence of stringent bottlenecks. The effective population size was on the higher end of the range reported for endangered sheep breeds. The knowledge on genetic diversity and effective population size coefficients would support the cause of conservation.

Pedigree analysis was extended to the Pêga donkey population in order to evaluate the status of genetic diversity and population structure. All parameters were computed for three reference populations of animals born between 2004 and 2014: all animals, animals with mouse gray coat color, and animals with roan coat color. Although the average inbreeding coefficient observed was low (about 3%), highly inbred animals are present in the current population. The effective population size based on the individual inbreeding rate was 35, while the effective population size based on the individual coancestry rate was about three times higher. The number of equivalent subpopulations was at around three, indicating that the Pêga donkey population is highly structured. There is no evidence of differentiation between subpopulations based on the coat color of the animals (Nei's minimum distance 0.10%). The breeding policy of Pêga donkeys is predominantly intra-herd. The loss of genetic diversity since the founder generations can be considered small in Pêga donkeys (1.25%). The excessive contribution of few ancestors to the gene pool may lead to narrower bottlenecks in the pedigree of this population in the future. The long generation interval in Pêga donkeys (10.7years) may be considered an advantage to reduce the increase in inbreeding and to maintain the genetic diversity of these animals.

Studies in Bovine Malignant Catarrh: VI. Adaptation to Rabbits

The winter feeding of beef cows represents a high, proportion of the costs of calf production. Attempts to minimise cost include the use of beef (♂) x dairy cows (♀) which have the ability to suckle two calves and to mobilise body reserves during periods of underfeeding in early lactation. Khan and Topps (1985) observed that cows in good condition at calving could maintain milk production and raise two good calves when given 110 MJ ME/day in a diet which included a source of undegradable protein. Subsequently a preliminary experiment was carried out with three single suckled and nine double suckled cows to examine the effect of energy level on the performance of cows and calves.Three single suckled cows and nine double suckled cows i.e. six with a natural plus foster calf and three with twin calves produced by embryo transfer were used in this experiment. The levels of energy that were examined were 70 or 90, 80 or 100 and 90 or 110 MJ ME/day for single and double-suckled cows respectively, supplied in diets containing ammonia treated straw, barley and fishmeal. Nine of the cows were placed into trios according to calving date and age, with a trio consisting of a cow with a natural calf, a cow with a natural and foster calf, and a cow with twin calves. Each trio was allocated at random to one of the three levels of energy. Similarly, the remaining three cows with a natural and foster calf were allocated at random to 90, 100 or 110 MJ ME/day. The calves were given good quality hay ad libitum and free access to a concentrate mixture up to a maximum intake of 2 kg/head/day. The concentrate mixture consisted of (g/kg) 800 barley, 150 soyabean meal and 50 molassine meal. The experiment started on the 22nd day of lactation and was of 20 weeks duration for most of the cows.

The inhibitory influence of the suckling stimulus on resumption of cyclicity post partum was elucidated for dairy cows by Oxenreider (1968) and for beef cattle by Short et al. (1972). In the traditionally managed herds in West Africa calves suckle their dam initially to stimulate milk let down, the cows are then milked and the calf is allowed to suckle the residual milk. Under such management calves normally suckle their dams for the entire lactation (mean 420 days, s.d. 138.6) as reported by Agyemang et al. (1990). In a trial to study milk conversion in the calf described by Agyemang et al. (1993) cows were allocated at calving to either a group in which they were milked the traditional way (n = 20), or to a group where calves were not allowed to suckle except for the first 4 days (n = 16). In the latter group milk let down was stimulated by oxytocin injection before morning and evening milking. All the cows were managed in the same herd and calved within a range of 2 months to avoid bias due to seasonal or nutritional influences. A fertile bull was always present in the herd. This study continues the work by Agyemang et al. (1993) by analysing the subsequent calving records of the dams to determine the differences in calving interval (CI) between the groups of suckled and non suckled cows. A summary of the data is given in Table I and these were analysed using the Wilcoxon 2 sample test. It was found that 60% of the non suckled cows had a CI of less than 390 days while 60% of the suckled cows had not calved by 480 days postpartum. The difference in the mean between the 2 groups of 138 days in favour of the non suckled group is highly significant (P < 0.01). The fate of 6 animals (37.5%) of the non-suckled group was not known and could not be determined in retrospect. Since these could have been cows with a very high CI a comparison was also made between the mean CI of the non-suckled group and 62-5% of the best animals of the suckled group revealing a reduced mean CI of 50 days in favour of non-suckled cows, 456 days and 406 days respectively.

Analysis of the Pedigree and Ancestors of the Cutting Population of the Quarter Horse Breed