Regina Roessler - Academia.edu (original) (raw)

Papers by Regina Roessler

Landtechnik, Dec 12, 2011

Die Kostenberechnungen für Maßnahmen zur Minderung von Ammoniakemissionen aus der Landwirtschaft ... more Die Kostenberechnungen für Maßnahmen zur Minderung von Ammoniakemissionen aus der Landwirtschaft wurden durch das KTBL aktualisiert. Im vorliegenden Beitrag werden die Minderungskosten für Maßnamen bei der Flüssigmistausbringung dargestellt. Je nach jährlich auszubringender Menge und je nach Technik treten Ausbringungskosten zwischen 2,5 und > 10 €/ m 3 auf. Als Minderungsverfahren ist bei geringen jährlichen Ausbringmengen von Rinder-und Schweinegülle die absetzige Einarbeitung mit 0,6-0,8 €/kg NH 3 besonders kosteneffektiv. Bei hohen Mengen und geteilten Ausbringverfahren ist die direkte Einarbeitung durch Güllegrubber mit 0,4-0,6 €/kg NH 3 effektiver.

Landtechnik, Feb 27, 2012

Nach der Veröffentlichung der Ammoniakminderungskosten für Maßnahmen bei der Lagerung und Ausbrin... more Nach der Veröffentlichung der Ammoniakminderungskosten für Maßnahmen bei der Lagerung und Ausbringung von Flüssigmist [1, 2] werden in diesem Beitrag die Minderungskosten für unterschiedliche Rohprotein-angepasste Fütterungsvarianten in der Mastschweinehaltung vorgestellt. Die Berechnung der Minderungskosten erfolgte auf Basis selbst ermittelter Stickstoffausscheidungen und Emissionsfaktoren. Die stärkste Reduzierung der N-Ausscheidung und damit verbunden der Ammoniakemissionen wird durch den Übergang von der Universalzur Zweiphasenmast erreicht. Die Einführung weiterer Phasenabschnitte führt nur zu vergleichsweise geringen weiteren Minderungen. Die höheren Kosten für die Fütterungstechnik und höheren Aminosäureeinsatz bei der Mehrphasenfütterung werden durch Einsparungen teurer Eiweißkomponenten ausgeglichen. Abhängig von Referenzverfahren, Anlagengröße und durchschnittlicher Wachstumsleistung der Tiere entstehen negative Minderungskosten in Höhe von-2,92 bis-16,14 €/kg NH 3. Bei den derzeitigen Kosten für Anlagentechnik und Futtermittel kann daher von einer deutlichen Kosteneinsparung durch eine Rohproteinangepasste Mehrphasenfütterung ausgegangen werden.

Ghana Journal of Science, Technology and Development, 2021

A study was conducted to evaluate apparent metabolizable energy (AME) and nutrient metabolisabili... more A study was conducted to evaluate apparent metabolizable energy (AME) and nutrient metabolisability (NM) of maize-based diets containing treated false yam seed meal (TFYSM) using a 5x6 factorial [5 treatment samples (Un_T, Urea_T, NaCl_T, NaOH_T and KOH_T) at 6 levels (0, 10, 20, 30, 40 and 50) each] design for 15 days. Matured false yam (Icacina oliviformis) fruits were harvested and seeds extracted. Five different FYSM samples were prepared. One untreated sample (Un_T) was prepared by crushing fresh false yam seed and sun-drying to 12% moisture. Four treated samples (T) were crushed and each soaked in water (1:2; w/v) for 12 days with water replaced every 3 days. Afterwards, each sample was re-soaked in 1 M concentration of urea (Urea_T), sodium chloride (NaCl_T), sodium hydroxide (NaOH_T) or potassium hydroxide (KOH_T), for 24 h, washed, blanched and sun-dried to a moisture content of 12%. Apparent metabolizable energy (AME) of the experimental diets indicated an increasing trend...

Animal, 2020

The laser methane detector (LMD) has been increasingly used in the last decade to assess the meth... more The laser methane detector (LMD) has been increasingly used in the last decade to assess the methane (CH 4) concentration in the exhaled air of ruminants. The CH 4 concentration was mostly measured indoors, where animals were either retained in a feed fence or manually by a person to facilitate the LMD measurements. By contrast, the use of the LMD for measurements under outdoor conditions has been limited to very few studies. The present study applied the LMD to assess the CH 4 concentration in air exhaled by four pasture-fed female Thuringian Forest goats when they were either expressing their natural grazing behaviour or when they were manually restrained at three times of the day during five consecutive days. We compared the activities, including rumination, and the CH 4 concentration between restrained and free-roaming goats, and between goats, days, times of the day and goats' activities. We hypothesised that the restraint influences the goats' behaviour, particularly rumination, which could lead to a change in CH 4 concentration. The overall CH 4 concentration (median) was not affected by goats' restraint (6.5 ppm-m for restrained vs. 6.6 ppm-m for free-roaming). However, restraint influenced goats' rumination activity, with differences between individual goats and days. A lower rumination activity was recorded on the first and the last two days as compared to Day 2-3. Despite the greater rumination activity, the CH 4 concentration was smaller on Day 2 (5.8 ppm-m) as compared to Day 5 (7.4 ppm-m). Similar observations were made with respect to behaviour and CH 4 concentrations in free-roaming goats. By contrast, no differences in the proportion of time of activities were found between the times of day for restrained goats, while free-roaming goats preferred to stand idle but were less frequently lying idle in late afternoon. Still, the greatest CH 4 concentration in restrained goats was obtained for the midday measurements (7.0 ppm-m), while it further increased until late afternoon for free-roaming goats (6.8 ppm-m). It is concluded that the restraint of animals during outdoor measurements can facilitate LMD measurements in grazing animals without changing the results for CH 4 concentration in air exhaled by the animal. An adaptation period of one day followed by two to three measurement days with sufficient measurement periods to account for different activities is recommended to limit the impact on animals' stress level.

Computers and Electronics in Agriculture, Jul 1, 2018

The Laser Methane Detector (LMD) technique has proven to be reliable for estimating enteric metha... more The Laser Methane Detector (LMD) technique has proven to be reliable for estimating enteric methane (CH 4) output in ruminants. The number of peer-reviewed publications related to LMD measurements in ruminants is still small. Studies are largely limited to measurements of animals in controlled research environment and respiration chambers, while measurements on animals outside respiration chambers are rare. Most studies focused on cattle or sheep, but the LMD has not yet been applied to goats. Finally, no systematic measurement protocol is available for different livestock species. Thus, the experimental setup of studies varies considerably, making a comparison of results difficult, although previous papers have provided guidance. In the present study, the LMD technique was applied in two experiments with goats to evaluate the effect of; the position of goats, the time after feeding, CH 4 peaks and troughs, the recording interval and the proportion of concentrate feed and hay in the diet on enteric CH 4 emission. Measurements were taken on four (Experiment 1) and 12 (Experiment 2) 1-year old female Boer goats. The position affected the mean enteric CH 4 emission, with higher values for lying than for standing goats. However, results across goats differ. In contrast, a day effect was observed that was consistent across positions and goats, with highest CH 4 emissions obtained for day 3 (Experiment 1). As could be expected, the time after feeding strongly influenced the CH 4 concentrations that were highest directly after morning feeding. CH 4 concentrations gradually decreased with increasing time after feeding and were lowest early in the morning. No diet effect (quality and quantity) was observed (Experiment 2). This indicates a high individual variation of enteric CH 4 emissions that could be exploited to select and breed animals with lower CH 4 output. For subsequent experiments utilizing the LMD technique, it is recommended to use a 0.1-s interval for recording point measurements of CH 4 concentrations, and for analysis to consider peaks only. A reduction of the recording interval to 1 s and 4 s only using CH 4 peaks led to high deviances from the reference (0.1-s records, CH 4 peaks and troughs), whereas the 0.1-s recording interval cleaned from CH 4 troughs and using only CH 4 peaks showed good accordance with the reference. Ongoing studies will verify the present results in view of developing a standardized protocol for measuring CH 4 output in the major ruminant livestock species.

Livestock Science, Nov 1, 2015

In villages of Northwest Vietnam, a community-based breeding program is being implemented that se... more In villages of Northwest Vietnam, a community-based breeding program is being implemented that serves distinct supply chains for pork from local pig breeds. The present study evaluated different selection scenarios for an effective breeding program under the specific framework conditions of smallholder pig production in the uplands of Northwest Vietnam. One-and two-step selection scenarios were considered for two nucleus populations of the local Ban and Mong Cai breeds. Two scenarios additionally considered the use of marker information on the estrogen receptor gene (ESR) in the Ban breed. The breeding planning calculations were performed with the software ZPLAN which is based on the gene flow and selection index methodology. In a deterministic approach, ZPLAN calculates genetic gains for breeding objective traits as well as the breeding profit sow À 1 in a defined period. Selected input parameters were varied to identify optimum levels to ensure the profitability of the breeding program. The most promising option with regard to economic viability and acceptable genetic gains is two-step selection. However, the population size in the breeding program has to be increased. One-step selection can also lead to acceptable genetic gains and economic success, but again only by increasing the population size parallel to a reduction in the nucleus size as well as the productive lifetime of nucleus sows. Using marker information on the ESR gene for selection in the Ban breed in the first selection step improves the genetic trend in number of piglets born alive (NBA). The use of marker information in the breeding program, however, seems questionable due to high costs, particularly because conventional index selection is supposed to also increase the frequency of the preferred ESR B allele in the Ban breed.

Livestock Science, Aug 1, 2009

Village breeding programmes are being developed by an integrated long-term project for smallholde... more Village breeding programmes are being developed by an integrated long-term project for smallholders in Northwest Vietnam to improve pig production in different production systems. In total, 120 smallholders with 169 sows in 5 of the 9 project villages were approached in single person interviews, using a structured questionnaire. Frequency analysis of data on breeding management and ranking of smallholders' trait preferences and selection criteria used for pigs were performed with SAS 9.1, using the FREQ procedure. Survey results indicate that both improved local breeds and exotic genotypes should be incorporated in future village breeding programmes for market-oriented smallholder pig production, improving the reproductive and growth performance as well as the carcass quality. In a next step, a model reflecting the status quo at farms with market-oriented pig production was developed integrating data from farmers' survey and information from the project's current recording scheme. A deterministic approach was used to assess the profitability and genetic merit of the current recording scheme. Modelling results show that the current recording scheme is unprofitable (− 33.90 € sow − 1). As continued success of village breeding programmes depends on the profitability of breeding measures, the long-term sustainability of the current recording scheme seems unlikely. Genetic gains are achieved in production and carcass quality traits, while a small reduction in reproduction traits can be observed. In a last step, possible effects of increased pig performances on the profitability and genetic merit of the current recording scheme were evaluated. Effects of increased pig performances on the genetic and economic success of the recording scheme are generally limited. Further model calculations are necessary for finding possibilities to improve smallholder pig breeding in a profitable way.

Archiv für Tierzucht, Oct 10, 2012

The concentration process in the international livestock breeding industry has led to an increasi... more The concentration process in the international livestock breeding industry has led to an increasing competitive pressure for existing regional livestock breeding institutions. This represents an almost insuperable barrier for the competitive organisation of livestock breeding under difficult framework conditions, particularly in developing countries. The present study aimed at identifying possibilities how to develop the organisation of livestock breeding under difficult framework conditions, taking smallholder pig breeding in mountainous areas in Northwest Vietnam as example. Information was collected from group discussions with small-scale pig producers in Son La province and interviews in various private and public breeding institutions across northern Vietnam, complemented by information from documents. Results show that smallholder pig breeding is influenced by numerous external private and public factors, respectively institutions. These include small private boar keepers and medium-sized commercial pig farms at village and district level, but also globally acting private breeding companies and relevant legislations. Considering the identified institutional framework situation of smallholder pig breeding at village level and the generally positive attitude of smallholders towards cooperative structures, the establishment of boar keeper cooperatives is recommended as a first step in the development of a competitive breeding organisation at village level. Altogether, the current situation of smallholder pig breeding at village level makes the establishment of village breeding programmes reasonable, given a more rigorous implementation of supportive legislations that promote and recognise the self-determination of the proposed cooperative breeding organisations.

Proceedings of the World Congress on Genetics Applied to Livestock Production, 2010

Livestock Science, Apr 1, 2010

This article appeared in a journal published by Elsevier. The attached copy is furnished to the a... more This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright

Journal of Dairy Science, Jun 1, 2022

Butana is one of the local dairy cattle breeds of Sudan commonly kept by smallholder producers. T... more Butana is one of the local dairy cattle breeds of Sudan commonly kept by smallholder producers. This breed has been strongly promoted to advance the dairy production sector in the country. The main problem, however, is the lack of a systematic breeding program that involves smallholder producers. The aim of the current study was to identify the most promising design for a breeding program to improve the milk yield performance of Butana cattle under smallholder production conditions. In total, 3 breeding scenarios, including (1) the use of farm bulls, (2) the use of village bulls, and (3) the rotational use of village bulls within village groups, were simulated using a stochastic simulation approach. For each breeding scenario, 3 selection methods for bulls were considered, namely random mating, phenotypic selection, and selection based on estimated breeding value (EBV). The results showed that no genetic gain was realized with random mating in all breeding scenarios. In the farm bull breeding scenario, annual genetic gain (standard deviation units) ranged from 0.01 to 0.19 (phenotypic selection) and from 0.01 to 0.39 (selection based on EBV). In the village bull breeding scenarios, the annual genetic gain ranged from 0.01 to 0.21 (phenotypic selection) and 0.01 to 0.45 (selection based on EBV). The lowest genetic gain was realized for the rotational use of village bulls among villages within groups. Through the rotational use of village bulls, however, a higher genetic variance was maintained than in the farm and village bull breeding scenarios. We concluded that a village bull breeding program with selection based on EBV of young bulls was the most promising breeding design for achieving the breeding goal. Further studies are needed to assess the organizational feasibility of such a breeding program to ensure the participation of smallholder producers and its sustainability.

Tropical Animal Health and Production, Nov 17, 2020

In Sudan, many Butana cattle farmers practice indiscriminate crossbreeding to improve the milk yi... more In Sudan, many Butana cattle farmers practice indiscriminate crossbreeding to improve the milk yield performance of cows, as organized breeding programs are lacking. Objectives of this study were to identify the current production conditions of Butana cattle and to determine farmers' production objectives and trait preferences using a field survey. The overall aim was to explore the possibility of establishing a community-based breeding program for the genetic improvement of the breed. A semi-structured questionnaire and field visits were used to collect data from 202 Butana cattle owners. Data were analyzed using chi-squared test, multiple response analysis, and binary logistic regression. Our results showed that Butana cattle farmers mainly raised their animals for milk production. On a five-point scale (5 = most important), milk yield (4.6 ± 0.05), growth performance (4.0 ± 0.07), and lactation length (3.9 ± 0.08) were highly preferred for future development of the breed. One-third of the farmers kept crossbred cattle with on average 4 crossbred animals per herd. About two-thirds of respondents were willing to adopt crossbreeding using exotic breeds to increase milk performance and about the same proportion were willing to exchange breeding bulls and establish farmers' associations. None of the respondents kept written performance records. However, educated farmers were more likely to adopt record keeping. Farmers' willingness to engage in associations could be useful for the establishment of a community-based breeding program. Based on the current farmers' production objectives, the future breeding program should emphasize increasing milk production of the Butana cattle by using improved Butana bulls in village herds.

Asian-australasian Journal of Animal Sciences, Jun 26, 2017

Objective: Our study provides information on phenotypes of local chickens and guinea fowl and the... more Objective: Our study provides information on phenotypes of local chickens and guinea fowl and their body measures as well as on major genes in local chickens in northern Ghana. Methods: Qualitative and morphometric traits were recorded on 788 local chickens and 394 guinea fowl in urban households in Tamale, Ghana. Results: The results showed considerable variation of color traits and numerous major genes in local chickens, while color variations and related genotypes in guinea fowl were limited. In local chickens, white was preferred for plumage, whereas dark colors were preferred for beak and shanks. More than half of the chickens carried at least one major gene, but the contributions of single gene carriers were low. All calculated allele frequencies were significantly lower than their expected Mendelian allele frequencies. We observed higher mean body weight and larger linear body measures in male as compared to female chickens. In female chickens, we detected a small effect of major genes on body weight and chest circumference. In addition, we found some associ ation between feather type and plumage color. In guinea fowl, seven distinct plumage colors were observed, of which pearl grey pied and pearl grey were the most prevalent. Male pearl grey pied guinea fowl were inferior to pearl grey and white guinea fowl in terms of body weight, body length and chest circumference; their shank length was lower than that of pearl grey fowl. Conclusion: Considerable variation in qualitative traits of local chickens may be indicative of genetic diversity within local chicken populations, but major genes were rare. In contrast, pheno typic and genetic diversity in local guinea fowl is limited. Broader genetic diversity studies and evaluation of trait preferences of local poultry producers are required for the design of appropriate breeding programs.

Journal of Animal Breeding and Genetics

Computers and Electronics in Agriculture, 2018

Veterinary Parasitology: Regional Studies and Reports

Endoparasite infections can lead to considerable economic losses in dairy cattle due to decreases... more Endoparasite infections can lead to considerable economic losses in dairy cattle due to decreases in milk yield and quality. Environmental and host-related factors contribute to endoparasite infection intensity and probability. Moreover, advancing urbanization influences parasite infection dynamics in livestock due to close human-animal cohabitation and changes in animal housing conditions. The aim of the present study was to investigate social-ecological effects on gastrointestinal nematode (GIN) and Eimeria spp. infections in dairy cattle along a rural-urban gradient in the emerging Indian megacity Bangalore. In this regard, 726 faecal samples from 441 dairy cattle of different ages and physiological stages were collected from 101 farms and examined at three visits between June 2017 and April 2018. Based on a survey stratification index (SSI) comprising built-up density and distance to the city center, we assigned the farms to urban, mixed and rural areas. GIN eggs were identified in the faeces of 243 cattle (33.5%; 95% confidence interval [CI]: 30.1-36.9%), and Eimeria spp. oocysts in the faeces of 151 cattle (20.8%; 95% CI: 17.9-23.7%). Co-infection rates of GIN and Eimeria spp. were 8.5 to 12.2% higher in rural compared to urban and mixed areas. The SSI effect significantly influenced Eimeria spp. infection probability and oocyst per gram of faeces (OpG; P < 0.001) with an infection probability and OpG higher than 26% and 40% for cattle kept in rural areas compared to cattle from urban areas. However, the SSI effect was not significant for the infection probability of GIN and for GIN eggs per gram of faeces (EpG). Infection probabilities and EpG/OpG were significantly higher in calves and heifers compared to lactating and dry cows. Moreover, we estimated significantly lower OpG values in summer compared to the other seasons. No differences were estimated for GIN and Eimeria spp. infection probabilities and EpG/OpG with regard to pasture access and breed. The variations in endoparasite infection intensity and probability observed along the rural-urban gradient of Bangalore reflect the variability in dairy husbandry systems governed by the social-ecological context.

Journal of Dairy Science, 2022

Livestock Science, 2015