Suckled Cows Research Articles

Risk Factors for Dystocia and Perinatal Mortality in Extensively Kept Angus Suckler Cows in Germany

Dystocia and perinatal mortality are major animal health, welfare and economic issues in beef suckler cow production. The objective of this study was to identify risk factors for dystocia and perinatal mortality and to analyze the relationships of both traits to external pelvic parameters in extensively kept beef suckler cows. Calving ease and calf survival were recorded for 785 births on five Angus cattle farms in Germany. The prevalence of dystocia and perinatal mortality was 3.4% and 4.3%, respectively. A hierarchical model was used to predict dystocia and perinatal mortality. First-parity dams had a higher probability of dystocia (p < 0.0001) than later-parity ones. Increasing birth weight was associated with an increasing risk for dystocia (p < 0.05). The probability of perinatal mortality (p < 0.0001) was higher in assisted births than in unassisted births. Calves from first-parity dams had a higher risk (p < 0.01) of being stillborn than calves from dams in later parities. An increase in the length of the pelvis was associated with an increase in odds for perinatal mortality (p < 0.001). In conclusion, the study indicates that dystocia and perinatal mortality are mainly problems in first-parity suckler cows. Concerning the predictive value of external pelvic parameters, further research is necessary.

Endocrine patterns of the post-partum cow

Summary. Milked dairy cows generally have a shorter post-partum interval to ovarian cyclicity than suckling dairy or beef cows. In milked and suckling cows, there is a strong seasonal influence with spring-calving cows remaining anoestrous longer. Increasing the suckling intensity further delays the onset of ovarian cyclicity, probably by increasing the frequency or strength of its inhibitory influence on hypothalamic activity. Plasma FSH levels rise in most cows 5–10 days after calving and thereafter the random changes observed have little relationship to the onset of cycles. Recovery of FSH release therefore occurs earlier post partum than recovery of LH release. Hyperprolactinaemia is not a cause of reproductive failure in milked or suckling cows because there is no correlation between plasma prolactin levels and the onset of ovarian cycles. Plasma LH concentrations undergo significant changes directly related to the initiation of ovarian cycles, with low plasma levels immediately post partum, followed by an increase in basal secretion and the development of clear LH episodes. This pulsatile pattern appears earlier in dairy than in beef cows and is further delayed by suckling compared to milking. Before the first ovulation there is an increased frequency and peak height of LH episodes leading to a rise in plasma LH levels and eventually to a preovulatory-type LH surge which results in the first ovulation. These changes in the pattern of LH release appear definitive in the initiation of ovarian activity in post-partum cows.

Pollution-Adjusted Productivity Changes: Extending the Färe–Primont Index with an Illustration with French Suckler Cow Farms

Several approaches have been proposed in the literature to compute technical efficiency indices that account for bad outputs. The literature is, however, less rich when it comes to incorporating bad outputs in productivity indices. In this context, this article extends the multiplicatively complete Fare–Primont productivity index to a generalized version that considers pollution. This novel pollution-adjusted total factor productivity (TFP) is the ratio of an aggregated measure of good outputs to an aggregated measure of bad outputs and non-polluting inputs, in such a way that the materials balance principle is not distorted. A decomposition of this new pollution-adjusted TFP is proposed using the by-production. The latter implies considering a technology that lies at the intersection of two sub-technologies: one for the production of good outputs and the other for the generation of pollution. The pollution-adjusted TFP is further decomposed into pollution-adjusted technical change and efficiency change. The latter is further broken down into technical, scale, mix, and residual efficiency change components. A crucial advantage of the Fare–Primont index is the verification of the transitivity property that allows multi-temporal and multilateral comparisons. The generalized (pollution-adjusted) Fare–Primont TFP proposed here is illustrated with a sample of French suckler cow farms surveyed over the period of 1990 to 2013. The bad outputs considered are greenhouse gas emissions, namely methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O). The results reveal a decrease in pollution-adjusted TFP by 5.57% during the period, due to technological regress of 2.23%, and to technical efficiency decrease of almost 3.34%.

Typology and structural characterisation of suckler cow farming system in Central Macedonia, Greece

The aim of this study was to establish a farm typology of the suckler cow sector, based on a stratified sample of 66 farms in the region of Central Macedonia, Greece. The method of hierarchical cluster analysis has been used to typology and characterisation of the farming system. The farm size was determined by the number of suckler cows and total livestock units. The degree of intensification of the farming system was classified based on the stocking rate of available pastures, labour efficiency, housing system and level of infrastructure. Cow productivity was evaluated as the weaned calves to cows’ ratio. The profitability and the dependence of farms on subsidies were estimated by using gross profit with or without the addition of total subsidies. Following the results, four principal farming systems and one diversified were highlighted: firstly, a traditional, pasture-based, semi-extensive system with low profitability and strong dependence on subsidies was identified. Secondly, a viable and relatively profitable, despite the lack of pasture land, semi-intensive system was revealed. The third one was also a semi-intensive system with high pasture availability and low reliance on subsidies. The intensive farming system that was represented by the fourth case was unsustainable due to the absence of available pastures. The semi-intensive one, which characterised as ‘diversified’ was not a pure suckler cow farming system as it was mainly based on purchased calves fattening.HIGHLIGHTSThe lack of pastures constrains the development of suckler cow farming sector in Central Macedonia, Greece.The low percentage of weaned calves (62%) leads to low capital outputs.Semi-intensive systems are best suited to ensuring the future viability of suckler cow farms with or without receiving subsidies.

Dynamic pollution-adjusted inefficiency under the by-production of bad outputs

This article extends the by-production model to the dynamic context of adjustment costs associated with investment. The empirical application focuses on panel data of French suckler cow farms over the period 1978–2014, considering emissions of greenhouse gases as bad output. The paper estimates input and output-specific technical inefficiency scores in the dynamic context and compares them with efficiency measures from the conventional static context. Our results reveal significant differences between inefficiency scores derived from the static and the dynamic frameworks. For all variables except meat production (the good output), the inefficiency score is lower in the dynamic context than in the static context.

PSXIII-1 Relationship between estrus expression detected by four methods and initial GnRH treatment with pregnancy per artificial insemination in suckler cows.

PSXIII-1 Relationship between estrus expression detected by four methods and initial GnRH treatment with pregnancy per artificial insemination in suckler cows.

267 Predicting dry matter intake in lactating beef and dairy crossbred suckler cows using novel animal measurements.

267 Predicting dry matter intake in lactating beef and dairy crossbred suckler cows using novel animal measurements.

294 Evaluation of production efficiencies among lactating beef and dairy crossbred suckler cows of diverse genetic merit.

294 Evaluation of production efficiencies among lactating beef and dairy crossbred suckler cows of diverse genetic merit.

Comparative grazing behaviour of lactating suckler cows of contrasting genetic merit and genotype

The objective of this study was to determine if differences in grazing behaviour exist between lactating suckler cows diverse in genetic merit for the national Irish Replacement index and of two contrasting genotypes. Data from 103 cows: 41 high and 62 low genetic merit, 43 beef and 60 beef x dairy (BDX) cows were available over a single grazing season in 2015. Milk yield, grass dry matter intake (GDMI), cow live weight (BW) and body condition score (BCS) were recorded during the experimental period, with subsequent measures of production efficiency extrapolated. Grazing behaviour data were recorded twice in conjunction with aforementioned measures, using Institute of Grassland and Environmental Research headset behaviour recorders. The effect of genotype and cow genetic merit during mid- and late-lactation on grazing behaviour phenotypes, milk yield, BW, BCS and GDMI were estimated using linear mixed models. Genetic merit had no significant effect on any production parameters investigated, with the exception that low genetic merit had a greater BCS than high genetic merit cows. Beef cows were heavier, had a greater BCS but produced less milk per day than BDX. The BDX cows produced more milk per 100 kg BW and per unit intake and had greater GDMI, intake per bite and rate of GDMI per 100 kg BW than beef cows. High genetic merit cows spent longer grazing and took more bites per day but had a lower rate of GDMI than low genetic merit cows, with the same trend found when expressed per unit of BW. High genetic merit cows spent longer grazing than low genetic merit cows when expressed on a per unit intake basis. Absolute rumination measures were similar across cow genotype and genetic merit. When expressed per unit BW, BDX cows spent longer ruminating per day compared to beef. However, on a per unit intake basis, beef cows ruminated longer and had more mastications than BDX. Intake per bite and rate of intake was positively correlated with GDMI per 100 kg BW. The current study implies that despite large differences in grazing behaviour between cows diverse in genetic merit, few differences were apparent in terms of production efficiency variables extrapolated. Conversely, differences in absolute grazing and ruminating behaviour measurements did not exist between beef cows of contrasting genotype. However, efficiency parameters investigated illustrate that BDX will subsequently convert herbage intake more efficiently to milk production.

The incidence of difficult calvings in the beef cattle in the Slovak Republic

Received: 2018-05-04 | Accepted: 2018-05-14 | Available online: 2018-11-26 https://doi.org/10.15414/afz.2018.21.04.135-137 Calving difficulty is one of important economic traits in beef production. In the Slovak Republic calving difficulty in beef cattle is recorded on the regular basis, however, these data have not been used so far in decision making. The aim of this study was to get the first insight into the data. Data on 288 346 calvings in 5 major Slovak populations (Charolais, Limousine, Slovak Simmental, Pinzgau, Beef Simmental) during the period 1990-2017 were exploited. The primary analyses showed that there exist differences in the incidence of the difficult calvings according to the breed of the dam. The lowest rate of assisted calvings was observed in Limousine breed. Lower incidence was observed when calvings of crossbred matings were considered. Only slight associations of difficult calvings with sex of calves, parity and season of calvings were observed. Slightly higher rates of assisted calvings were observed in the group of heifers and births of males. Keywords: beef cattle, calving ease, dystocia, reproduction References Atashi, H., Abdolmohammadi, A., Dadpasand, M., Asaadi, A. (2012) Prevalence, risk factors and consequent effect of dystocia in Holstein dairy cows in Iran. Asian-Australasian Journal of Animal Science, 25 (4), 447-451. DOI: https://dx.doi.org/10.5713/ajas.2011.11303 Carnier, P., Albera, A., Dal Zotto, R., Groen, A. F., Bona, M., Bittante, G. (2000) Genetic parameters for direct and maternal calving ability over parities in Piedmontese cattle. Journal of Animal Science, 78 (10), 2532-2539. DOI: https://dx.doi.org/10.2527/2000.78102532x De Amicis, I., Veronesi, M.C., Robbe, D., Gloria, A., Carluccio, A. (2018) Prevalence, causes, resolution and consequences of bovine dystocia in Italy. Theriogenology, 107, 104-108. DOI: https://dx.doi.org/10.1016/j.theriogenology.2017.11.001 Eriksson, S., Nasholm, A., Johansson, K., Philipsson, J. (2004) Genetic parameters for calving difficulty, stillbirth, and birth weight for Hereford and Charolais at first and later parities. Journal of Animal Science, 82 (2), 375-383. DOI: https://dx.doi.org/10.1093/ansci/82.2.375 Fuerst, C., Egger-Danner, C. (2003) Multivariate genetic evaluation for calving ease and stillbirth in Austria and Germany. [Online] Interbull bulletin, 31, 47 - 51. Available at: http://agtr.ilri.cgiar.org/documents/Library/docs/Interbull/bulletin31_files/docs/Fuerst.pdf [Accessed 5 March 2018] Jamrozik, J., Miller, S.P. (2014) Genetic evaluation of calving ease in Canadian Simmentals using birth weight and gestation length as correlated traits. Livestock Science, 162, 42-49. DOI: https://dx.doi.org/10.1016/j.livsci.2014.01.027 Juozaitiene, V., Juozaitis, A., Kardisauskas, A., Zymantiene, J., Zilaitis, V., Antanaitis, R., Ruzauskas, M. (2017) Relationship between dystocia and the lactation number, stillbirth and mastitis prevalence in dairy cows. Acta Veterinaria. Brno 86, 345-352. DOI: https://dx.doi.org/10.2754/avb201786040345 Lopez De Maturana, E., Ugarte, E., Komen, J., Van Arendonk, J. (2007) Consequences of selection for yield traits on calving ease performance. Journal of Dairy Science, 90 (5), p. 2497-2505. DOI: https://dx.doi.org/10.3168/jds.2006-415 McHugh, N., Cromie, A. R., Evans, R. D., Berry, D. P. (2014) Validation of national genetic evaluations for maternal beef cattle traits using Irish field data. Journal of Animal Science, 92, 1423-1432. DOI: https://dx.doi.org/10.2527/jas.2013-6658 Mekonnen, M., Moges, N. (2016) A Review on Dystocia in Cows. European Journal of Biological Sciences, 8 (3), 91-100. DOI: https://dx.doi.org/10.5829/idosi.ejbs.2016.91.100 Motus, K., Emanuelson, U. (2017) Risk factors for on-farm mortality in beef suckler cows under extensive keeping management. Research in Veterinary Science, 113, 5-12. DOI: https://dx.doi.org/10.1016/j.rvsc.2017.08.007 Phocas, F., Laloe, D. (2004) Genetic parameters for birth and weaning traits in French specialized beef cattle breeds. Journal of Dairy Science, 89 (2-3), 121-128. DOI: https://dx.doi.org/10.1016/j.livprodsci.2004.02.007 Steinbock, L., A. Nasholm, B. Berglund, K. Johansson, And J. Philipsson. (2003) Genetic effects on stillbirth and calving difficulty in Swedish Holsteins at first and second calving. Journal of Dairy Science, 86 (6), 2228-2235. DOI: https://dx.doi.org/10.3168/jds.S0022-0302(03)73813-2 Uematsu, M., Sasaki, Y., Kitahara, G., Sameshima, H., Osawa, T. (2013) Risk factors for stillbirth and dystocia in Japanese Black cattle. The Veterinary Journal, 198 (1), 212-216. DOI: http://dx.doi.org/10.1016/j.tvjl.2013.07.016

Dioxins and PCBs in Meat - Still a Matter of Concern?

Polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) summarized as dioxins, as well as polychlorinated biphenyls (PCBs) are persistent, bio-accumulative and toxic environmental contaminants. Over 95% of human exposure to these problematic chemicals occurs via the ingestion of fatty rich food like meat and meat products, fatty fish, as well as milk and dairy products. Several major food and feed contamination incidents in Europe during the years 1997 and 2010 revealed the necessity of establishing food and feed monitoring programs for dioxins and PCBs. Various monitoring programs carried out by the Federal Office of Public Health (FOPH) and the Federal Food Safety and Veterinary Office (FSVO), suggest that cattle from extensive farming (suckler cow husbandry) exhibited higher levels of dioxin-like PCBs (dl-PCBs) and exceeded with higher frequency the permitted maximum levels (ML) when compared to conventional raised cattle. The reasons for the higher levels are possibly due to higher levels of PCBs in green fodder (pasture, silage, and hay) when compared to the concentrated feed used in conventional farming. Additionally, an increased uptake of soil, which is known to be a risk matrix for the uptake of dioxins and PCBs in grazing animals, leads to elevated contaminant levels in the suckler cows and hence their calves. Furthermore, PCB point sources present on a farm from older building and construction materials (e.g. PCB-containing wall paints) might result in very high contamination of the animals and the meat produced from them.

Blood immune transcriptome analysis of artificially fed dairy calves and naturally suckled beef calves from birth to 7 days of age

Neonatal calves possess a very immature and naïve immune system and are reliant on the intake of maternal colostrum for passive transfer of immunoglobulins. Variation in colostrum management of beef and dairy calves is thought to affect early immune development. Therefore, the objective of this study was to examine changes in gene expression and investigate molecular pathways involved in the immune-competence development of neonatal Holstein dairy calves and naturally suckled beef calves using next generation RNA-sequencing during the first week of life. Jugular whole blood samples were collected from Holstein (H) dairy calves (n = 8) artificially fed 5% B.W. colostrum, and from beef calves which were the progenies of Charolais-Limousin (CL; n = 7) and Limousin-Friesian beef suckler cows (LF; n = 7), for subsequent RNA isolation. In dairy calves, there was a surge in pro-inflammatory cytokine gene expression possibly due to the stress of separation from the dam. LF calves exhibited early signs of humoral immune development with observed increases in the expression genes coding for Ig receptors, which was not evident in the other breeds by 7 days of age. Immune and health related DEGs identified as upregulated in beef calves are prospective contender genes for the classification of biomarkers for immune-competence development, and will contribute towards a greater understanding of the development of an immune response in neonatal calves.

Suckler cow efficiency – breed by environment interactions in commercial herds under various natural production conditions

ABSTRACTThe significance of breed by environment interaction on suckler cow efficiency traits was investigated, using production data from the Norwegian Beef Cattle Recording System and data collected (feed regimes, etc.) from 27 commercial suckler cow herds. Two statistical approaches were used; mean breed performance in extensive/intensive environments (mixed models), or as within breed regressions of cow performance on modelled cow energy intake. Aberdeen Angus produced higher weaning weight than Hereford below 12,000 MJ NE (241 kg) and Charolais below 13,000 MJ NE (244 kg) cow energy intake in the suckler period, after which the breeds re-ranked. The corresponding re-rank between Hereford and Charolais was at 14,500 MJ NE (263 kg) cow energy intake. Overall, breed by environment interactions were observed for calving interval, number/kg calves weaned/mated cow/year and energy efficiency, which emphasise that choice of cow breed should be dependent on the natural production resources available.

Carbon Footprint of Beef Cattle in a Conventional Production System: a Case Study of a Large-Area Farming Enterprise in the Wielkopolska Region

Animal production is a significant source of greenhouse gas (GHG) emissions. One of the major challenges in sustainable management is to mitigate the effects of climate change by reducing GHG emissions. The diversity of animal production systems and accompanying diversification of technological processes, mean that specific production effects can be obtained at different levels of GHG emissions. The aim of the study was to determine the carbon footprint (CF) of beef cattle grown in a conventional system (i.e. indoor confinement). The research was carried out on the beef cattle farm belonging to a large-area enterprise, Długie Stare Ltd. The beef cattle production system consisted of the following subsystems: a basic breeding herd (consisting of suckler cows, replacement heifers and calves up to 6.5 months), breeding heifers, breeding bulls and fattening bulls. The method of life cycle analysis (LCA) in the stages from "cradle-to-farmgate" was used to assess the GHG emissions associated with the production of beef cattle. The average CF in the entire beef cattle production system was 25.43 kg of CO2 kg-1 of live weight of marketed cattle, while in the individual subsystems of basic breeding herd, breeding heifers, breeding bulls and fattening bulls, the CF (after GHG allocation) was: 11.0 kg CO2 eq., 34.30 kg CO2 eq., 27.32 and 25.40 kg CO2 eq., respectively. GHG emissions associated with young calves staying in the cow-calf pairs until weaning (in the period from 0-6.5 months), had a decisive influence on the final CF in each of the subsystems of beef cattle production. The second important factor directly affecting the CF was GHG emissions related to methane (CH4) enteric fermentation and manure management. Knowledge of factors affecting the CF structure allows better identification of critical areas in production processes with high GHG emission potential. Information on the CF of beef cattle and beef meat responds to a wider societal demand for the ecological characteristics of market products, which ultimately contributes to improving their market competitiveness.

A Field Study on the Prevalence of and Risk Factors for Endoparasites in Beef Suckler Cow Herds in Germany

Endoparasites are one of the major health issues in beef suckler cows and can cause economic losses. As studies on the parasitological status of beef suckler cow herds are rare, the aim of this study was to evaluate the status quo of the parasite burden in herds at four representative locations in Germany. Additionally, the farmers’ pasture management and deworming strategies were documented. Based on these data, the second aim of the study was to develop recommendations for improved deworming and pasture hygiene management. A total of 708 faecal samples were examined with parasitological routine methods. Results revealed Fasciola hepatica, gastrointestinal nematodes (GIN), Eimeria species (spp.), Moniezia spp. and Dictyocaulus viviparus as the most frequent findings. Clinical signs of parasitic diseases were not found during the farm visits. Statistical analyses showed a significant effect of the age status of the animal on the parasitological status in general. Due to the percentage of occurrence, detailed statistical analysis was performed for Eimeria, GIN and Fasciola hepatica, confirming the effect of age status. Assessing the parasitological status of beef suckler cows as routine procedure could help to establish an improved parasite-control management on a farm-individual basis.

Assessment of Profitability and Break-Even Points in Suckler Cow Herds

Suckler cow enterprises comprise an important segment of Czech agriculture, and the number of suckler cows has been steadily increasing in recent years. The objective of this study was to assess the profitability of suckler cow herds in the Czech Republic based upon data collected for 2014, 2015, and 2016 using a questionnaire covering production, reproduction, and economic traits. The average yearly costs reached 30,583 CZK per cow. When subsidies in the average amount of 14,347 CZK per cow were included, profitability of 8.3, 8.7, and 6.3 % was observed in 2014, 2015, and 2016, respectively. Feed, labour, depreciation, and overheads were the largest cost items and together comprised 66 % of total yearly costs. The data obtained proved the economy of scale. Average break-even points were determined for the number of weaned calves, calving interval, and selling price of calves (75 calves, 465 days, and 56 CZK/kg live weight, respectively). A sensitivity analysis identified the number of weaned calves, price of calves, calving interval, and amount of subsidies as the most influential parameters.

Three decades of productivity change in French beef production: a Färe‐Primont index decomposition

The Färe‐Primont index is used to evaluate total factor productivity (TFP) change and its components for a sample of French suckler cow farms in grassland areas in 1985–2014. The results reveal an increase in TFP of 6.6 per cent over the whole observation period, with technological progress being the major source of productivity growth. Meanwhile, efficiency decreased. Farms experienced great technological progress from 1991 to 2000. From a methodological point of view, the comparison with results obtained with Malmquist indexes shows similar trends but different magnitudes, with the Malmquist index overestimating the TFP and technological changes compared to the Färe‐Primont index. In addition, the use of a sequential approach that restricts technological change to being positive or null allows for the precise calculation of technology changes, disregarding the effects of external conditions that are captured in efficiency changes. Finally, the estimation of full dimensional efficient facets (FDEFs) that guarantees the positivity of all shadow prices used to assess the mix efficiency component of TFP change is promising.

Production laitière à l’ouest du Burkina Faso dans un contexte d’émergence de laiteries : diversité des pratiques d’élevage et propositions d’amélioration

Dans l’ouest du Burkina Faso, des laiteries se heurtent à un problème d’approvisionnement en lait local, car la production est faible, saisonnée, atomisée et coûteuse à collecter. Cette étude a eu pour objectif d’identifier des leviers pour augmenter la production et réduire la saisonnalité. Elle a été réalisée chez 18 polyculteurs-éleveurs de la région des Hauts-Bassins impliqués dans la production de lait. Une analyse multivariée basée sur des variables de structures, de fonctionnement et de performance des exploitations a permis d’identifier cinq types de polyculteurs-éleveurs impliqués dans cette production : « les allaitants » à faible niveau d’intrants et à orientation pastorale à grands effectifs de vaches (T1), à effectifs moyens (T2) ; les allaitants à orientation agropastorale (T3) ; les laitiers spécialisés et à visée commerciale ayant peu recours aux fourrages verts (T4), ou à forte utilisation de fourrage vert (T5). Les types T1 et T2 se caractérisaient par une alimentation quasi exclusive au pâturage en toute saison, et un niveau de production de lait inférieur à deux litres par vache par jour au pic de lactation. Le lait issu de ces exploitations était faiblement commercialisé et rarement vendu aux laiteries. Les types T3 ont davantage eu recours aux fourrages secs et aux aliments, ce qui leur a permis d’améliorer leur production de lait commercialisée fréquemment en laiterie (env. 2 L/vache/jour au pic de lactation). Les types T4 et T5 se caractérisaient par un recours à des races améliorées, et une utilisation importante de fourrages et d’aliments achetés toute l’année, leur assurant une production de lait plus élevée (5–13 L/vache/jour au pic de lactation). Ces exploitations vendaient leur lait en totalité à la laiterie. Nos résultats soulignent que la production était fortement pénalisée par une alimentation trop pauvre en aliments et en fourrages de qualité, et que la saisonnalité des mises bas aggravait la chute de production en fin de saison sèche.

Fatores Determinantes na Incorporação das Organizações ao ISE

In 2006, new maximum levels for the concentration of dioxins (PCDD/F) and dioxin-like PCB (dl-PCB) in food entered into force in the European Union [Regulation (EC) No 199/2006]. The Swiss Confederation decided to adopt these values from the 1 January 2009 on (RS 817.021.23). A previous appraisal showed that beef from extensive production systems in Switzerland may exceed the new maximum level of 4.5 pg WHO97-TEQ·g-1 fat. In order to identify the reasons of the presence of dioxins (PCDD/F) and dioxin-like PCB in Swiss beef, a detailed survey was conducted on eight farms in 2008. Depending on the production system, on each farm several suckler cows and their calves or fattening bulls and heifers were selected and followed over several months. Samples of soil, milk, forages, concentrates and meat were taken and analyzed according to standard protocols. The sum of PCDD/F and dl-PCBs in soil averaged 1.4 pg WHO97-TEQ·g-1 dry matter (DM) across all farms. The mean value found in feed samples was 0.25 pg WHO97-TEQ·g-1 feed (88% DM), which is considerably lower than the legal maximum level of 1.25 pg WHO97-TEQ·g-1 feed. The mean value of milk from suckler cows was 2.75 pg, and the one of milk from dairy cows was 2 pg WHO97-TEQ·g-1 fat. Although two individual beef samples (out of 36) slightly exceeded the legal limit of 4.5 pg WHO97-TEQ·g-1 fat, the mean value of all beef samples was 2.3 pg WHO97-TEQ·g-1 fat. The results did not allow to establish direct relationships between the presence of contaminants in feeds and milk or beef and they showed that variation in PCDD/F and dl-PCB contamination of meat within the same farm was very high. It can be concluded that the situation in Switzerland seems not to be alarming and that no particular measures have to be taken. Nevertheless farmers should be aware that extensive production coupled with absence of delay between weaning and slaughtering may induce some risk for producing non compliant beef.

Decreasing from 9 to 7 days the permanence of progesterone inserts make possible their use up to 5 folds in suckled Nellore cows

This study aimed to evaluate the effects of decreasing permanence period of progesterone (P4) inserts from 9 (9d) to 7 (7d) days in timed-AI (TAI) protocol, as well as their reuse on pregnancy per AI (P/AI) during 7d protocol. At the beginning of all protocols, cows received 2 mg of estradiol benzoate (EB) and a vaginal insert containing 1.9 g of P4. In the 7d protocol, the P4 insert was removed, and cows were given 25 mg of prostaglandin F2α, 0.6 mg of estradiol cypionate and 300 IU of eCG 7 days later. In the 9d protocol, the P4 insert was removed, and cows received the same hormones that were administrated in 7d protocol, however, they were applied on the 9th day of the protocol. In the experiment I, 302 suckled Nellore cows were undergone to 7d protocol, and AI was performed 10–14 h later after estrus detection. In the experiment II, 679 suckled Nellore cows were assigned to receive either 7d or 9d protocols. In the experiment III, 999 suckled Nellore cows were assigned to receive either a new P4 insert (CIDR1), or a P4 insert used previously for 7 (CIDR2), 14 (CIDR3), 21 (CIDR4) or 28 (CIDR5) days, and 227 Nellore heifers received a P4 insert used previously for 21 (CIDR4) or 35 (CIDR6) days during the 7d protocol. When 7d protocol was used, 45% of cows exhibited estrus 48 h after P4 removal. Thus, the AI was performed 55 h after P4 removal in experiments II and III when 7d protocol was used. There was no difference in estrus detection rate (72 vs 74%; P = 0.60), ovulation rate (80 vs 88%; P = 0.13) and P/AI (56 vs 54%; P = 0.49) between 7d and 9d protocols, respectively. In the 7d protocol, the P/AI was similar (P = 0.72) using a new P4 insert (47%), or a P4 insert used previously for 7 (48%), 14 (45%), 21 (54%), or 28 (49%) days in Nellore suckled cows. In addition, P/AI was similar (P = 0.15) in heifers that received a P4 insert used previously for 21 (52%), or 35 (61%) days during the 7d protocol. In conclusion, cows submitted to 7d or 9d protocols had similar reproductive performance, and the reuse of P4 inserts up to 6 folds (five in suckled cows plus one in heifers) did not affect reproductive performance of Nellore cattle in 7d protocol.