Environmental Impact assessment of a semi-intensive beef cattle production in Brazil’s Northeast

Purpose

The aim of this study is to identify and evaluate the main environmental impacts related to semi-intensive beef cattle production system in the State of Bahia, in Brazil’s Northeast.

Methods

A cradle to gate study was undertaken in a beef cattle production system comprising two stages: calves production in one farm (farm 1) and cattle production in another farm (farm 2), both located in the central-southern meso-region of Bahia. The functional unit was 1?kg live weight. Impact assessment was performed using five impact categories from the ReCiPe method.

Results and discussion

When compared to calves, the cattle production had the greatest contributions in all of the five studied impact categories. The process pasture cultivation had expressive environmental impacts in all categories, with 70.05 % for climate change (CC), 82.01 % for terrestrial acidification (TA), 76.53 % for fossil depletion (FD), 86.14 % for freshwater eutrophication (FE) and 100 % for agricultural land occupation (ALO). In CC and TA, the principal elementary flow was the direct emissions due to the use of mineral fertilizers. In FE and FD, the dominant flow was related to the use of phosphate fertilizer. In ALO, the process pasture cultivation was predominant due to the physical area of the farms, which is a characteristic of pasture-based production systems. The processes breeding-rearing and fattening were second in the contribution analysis, with 29.95 % and 17.99 %, respectively, for CC and TA, due to the enteric methane (CH₄) and the direct emissions of nitrous oxide (N₂O) volatilization from the animal excreta.

Conclusions

The cattle production is responsible for the greater part of impacts, compared to the calves production. The direct emissions from fertilizers used in the pastures, from enteric emissions and from animal wastes in the breeding-rearing and fattening processes were identified as the critical points of the analysed cattle production system. Measures aiming at the improvement of the feed conversion of the animals and at the substitution of synthetic nitrogen fertilizers by natural nitrogen fixation can considerably contribute to the reduction of environmental impacts of these production systems. Accordingly, the respective modifications should be considered in future studies on the potential of these measures to enhance the environmental performance of semi-intensive beef cattle production. These results will complement other similar studies conducted in other regions of the country, following the tendency of growing usage of the life cycle assessment methodology in Brazilian agricultural and livestock systems.

     

Impact of automatic milking systems on dairy cattle producers’ reports of milking labour management,milk production and milk quality

Automatic milking systems (AMS), or milking robots, are becoming widely accepted as a milking technology that reduces labour and increases milk yield. However, reported amount of labour saved, changes in milk yield, and milk quality when transitioning to AMS vary widely. The purpose of this study was to document the impact of adopting AMS on farms with regards to reported changes in milking labour management, milk production, milk quality, and participation in dairy herd improvement (DHI) programmes. A survey was conducted across Canada over the phone, online, and in-person. In total, 530 AMS farms were contacted between May 2014 and the end of June 2015. A total of 217 AMS producers participated in the General Survey (Part 1), resulting in a 41% response rate, and 69 of the respondents completed the more detailed follow-up questions (Part 2). On average, after adopting AMS, the number of employees (full- and part-time non-family labour combined) decreased from 2.5 to 2.0, whereas time devoted to milking-related activities decreased by 62% (from 5.2 to 2.0 h/day). Median milking frequency was 3.0 milkings/day and robots were occupied on average 77% of the day. Producers went to fetch cows a median of 2 times/day, with a median of 3 fetch cows or 4% of the herd per robot/day. Farms had a median of 2.5 failed or incomplete milkings/robot per day. Producers reported an increase in milk yield, but little effect on milk quality. Mean milk yield on AMS farms was 32.6 kg/cow day. Median bulk tank somatic cell count was 180 000 cells/ml. Median milk fat on AMS farms was 4.0% and median milk protein was 3.3%. At the time of the survey, 67% of producers were current participants of a DHI programme. Half of the producers who were not DHI participants had stopped participation after adopting AMS. Overall, this study characterized impacts of adopting AMS and may be a useful guide for making this transition.     

Farm-level emission intensities of smallholder cattle (Bos indicus; B. indicus–B. taurus crosses) production systems in highlands and semi-arid regions

Ruminants are central to the economic and nutritional life of much of sub-Saharan Africa, but cattle are now blamed for having a disproportionately large negative environmental impact through emissions of greenhouse gas (GHG). However, the mechanism underlying excessive emissions occurring only on some farms is imperfectly understood. Reliable estimates of emissions themselves are frequently lacking due to a paucity of reliable data. Employing individual animal records obtained at regular farm visits, this study quantified farm-level emission intensities (EIs) of greenhouse gases of smallholder farms in three counties in Western Kenya. CP was chosen as the functional unit to capture the outputs of both milk and meat. The results showed that milk is responsible for 80–85% of total CP output. Farm EI ranged widely from 20 to >1 000 kg CO₂-eq/kg CP. Median EIs were 60 (Nandi), 71 (Bomet), and 90 (Nyando) kg CO₂-eq/kg. Although median EIs referenced to milk alone (2.3 kg CO₂-eq/kg milk) were almost twice that reported for Europe, up to 50% of farms had EIs comparable to the mean Pan-European EIs. Enteric methane (CH₄) contributed >95% of emissions and manure ～4%, with negligible emissions attributed to inputs to the production system. Collecting data from individual animals on smallholder farms enabled the demonstration of extremely heterogeneous EI status among similar geographical spaces and provides clear indicators on how low EI status may be achieved in these environments. Contrary to common belief, our data show that industrial-style intensification is not required to achieve low EI. Enteric CH₄ production overwhelmingly drives farm emissions in these systems and as this is strongly collinear with nutrition and intake, an effort will be required to achieve an “efficient frontier” between feed intake, productivity, and GHG emissions.     

Count Bayesian models for genetic analysis of in vitro embryo production traits in Guzerá cattle

Four models for in vitro embryo production traits in Guzerá cattle were compared: Gaussian (untransformed variable – LIN and transformed in logarithmic scale – LOG), Poisson (POI) and zero-inflated Poisson (ZIP). Data consisted of 5716 ovum pick-up and in vitro fertilization records performed in 1205 cows from distinct regions of Brazil. Analyzed count traits were the number of viable oocytes (N_OV), number of grade I oocytes (N_GI), number of degenerated oocytes (N_DG), number of cleaved embryos (N_CLV) and number of viable produced embryos (N_EMB). Heritability varied from 0.17 (LIN) to 0.25 (POI) for N_OV; 0.08 (LOG) to 0.18 (ZIP) for N_GI; 0.12 (LIN) to 0.20 (POI) for N_DG; 0.13 (LIN) to 0.19 (POI) for N_CLV; 0.10 (LIN) to 0.20 (POI) for N_EMB depending on the considered model. The estimated repeatability varied from 0.53 (LOG) to 0.63 (POI) for N_OV; 0.22 (LOG) to 0.39 (ZIP) for N_GI; 0.29 (LIN) to 0.42 (ZIP) for N_DG; 0.42 (LIN) to 0.59 (POI) for N_CLV; 0.36 (LIN) to 0.51 (POI) for N_EMB. The goodness of fit, measured by deviance information criterion and mean squared residuals, suggested superiority of POI and ZIP over Gaussian models. Estimated breeding values (EBV) obtained by different models were highly correlated, varying from 0.92 for N_OV (between LIN-POI) and 0.99 for N_GI (between POI-ZIP). The number of coincident animals on the 10% top EBV showed lower similarities. We recommend POI and ZIP models as the most adequate for genetic analysis of in vitro embryo production traits in Guzerá cattle.     

Deficiency of α-mannosidase in Angus cattle. An inherited lysosomal storage disease

A disease of Angus cattle previously known as pseudolipidosis has been shown to be an inherited lysosomal storage disease, in which an oligosaccharide containing mannose and glucosamine is the storage substance. Diseased animals have a near-absolute deficiency of the lysosomal enzyme, alpha-mannosidase, whereas heterozygotes have a partial deficiency of this enzyme. The condition is analogous to the human disease known as mannosidosis.     

Hyper production of β-glucosidase by an Aspergillus sp.

Summary An Aspergillus sp. was isolated which secreted high levels of -glucosidase in growth medium. The maximum activity(10 IU/ml of -glucosidase and 22.6 IU/ml of cellobiase) was obtained in cellulose medium supplemented with wheat bran. The pH and temperature optima for this enzyme were 4.5 and 65°C respectively.NCL Communication No. 3616     

Inbreeding effects on in vitro embryo production traits in Guzerá cattle

Inbreeding has been associated with the impairment of reproductive performance in many cattle breeds. Although the usage of reproductive biotechnologies has been increasing in bovine populations, not much attention has been given to the impact of inbreeding over cow’s performance on artificial reproduction. The objective of this study was to estimate the impact of inbreeding on in vitro embryo production in a Guzerá breed population. The inbreeding coefficient (F), calculated as half of the co-ancestry of the individual’s parents, was used as an estimate of inbreeding. The inbreeding coefficients of the donor, sire (used on in vitro fertilization) and of the embryos were included, separately, in the proposed models either as classificatory or continuous variables (linear and quadratic effects). The percentage of non-inbred individuals (or embryos) and mean F of donors, embryos and sires were 29.38%; 35.76%; 42.86% and 1.98±2.68; 1.32±3.13; 2.08±2.79, respectively. Two different models were considered, one for oocyte production traits and other for embryo production traits. The increase of F of the donor significantly (P<0.05) impaired the number of viable oocytes (N_OV), number of grade I oocytes (N_GI) and number of cleaved embryos (N_CLV). Moreover, the donor’s F influenced the percentage of grade I oocytes (P_GI), percentage of viable embryos (P_EMB) and percentage of cleaved embryos that turned into embryos (P_CXE). No significant (P>0.05) effects were observed for the sire (father of the embryos) inbreeding coefficient over the traits analysed. Embryo’s F influenced (P<0.05) the number of viable embryos (N_EMB), percentage of viable embryos (P_EMB) and percentage of cleaved embryos that turn into embryos (P_CXE). Results suggested that an increase in the inbreeding coefficient might impair the embryos ability to survive through challenges imposed by the in vitro environment. Submitting highly inbred Guzerá female donors to in vitro embryo production may, in the long-term, have negative implications on the number of embryos obtained per cow and increase the relative costs of the improvement programmes based on this technology. High levels of inbreeding should be avoided when selecting Guzerá female donors and planning in vitro fertilization mating.     

Cellobiose dehydrogenase influences the production of S. microspora β-glucosidase

BglG, a Stachybotrys microspora β-glucosidase produced in the presence of glucose and cellobiose, was used individually as sole carbon source. The time course synthesis of BglG showed two aspects: (1) an exponential curve, observed in glucose Mandels medium, and (2) a cloche curve, observed in cellobiose containing cultures. A decrease was observed in bglG production at the 6th, 8th and 10th days during mycelium growth in cellobiose Mandels medium, which allowed for the assumption that the anabolism of a bglG inhibitor factor was produced with cellobiose but not with glucose. Cellobiose dehydrogenases (CDH) activity was, on another hand detected in cellobiose grown cultures but not in glucose containing ones. The aliquots, withdrawn at the time course of bglG production in the presence of cellobiose, gave rise to an inhibitory effect on bglG activity. This result was obtained with and without the heat treatment (5 min at 100°C) of the aliquots, which supported the non-proteinaceous nature of the inhibitor factor. Furthermore, sugar chromatographic analyses revealed the appearance of a secondary metabolite in the cellobiose Mandels medium and indicated that the factor behind the bglG activity cloche curve was a δ-gluconolactone. Seeing that the latter follows a strong inhibitory effect on bglG activity, it is speculated that the decrease in bglG activity during the time course of bglG synthesis in cellobiose Mandels medium is assigned to the release of δ-gluconolactone. This paper presents and validates an explanatory model for this hypothesis.     

‘Seed’ production of Porphyra spp. by tissue culture

Differentiation of archeospores was observed from excised tissue of young thalli of various monoecious Porphyra species ( P. tenera, P. yezoensis, P. suborbiculata, P. okamurae) after 4–8 days in culture at temperatures of 20 and 25 °C. Excised tissue from adult thalli did not differentiate into archeospores, but rather regenerated directly into blades and rhizoids of foliose thalli. Tissues from young thalli of two dioecious Porphyra species ( P. dentata and P. pseudolinearis) also regenerated into blades and rhizoids after manipulation of the culture conditions. In addition, 1–2 celled tissue pieces of both monoecious and dioecious species were also seen to develop directly into blades. Polarity of regeneration of blades and rhizoids was observed in these species. These results suggest that ‘seed’ can be obtained through tissue culture instead of using conventional conchocelis culture for commercial nori aquaculture in Japan. This revised version was published online in June 2006 with corrections to the Cover Date.     

Factors influencing aboveground production of Scirpus marshes in the St. Lawrence estuary,Québec,Canada

Aboveground production of macrophytes in tidal marshes was studied for 3 years at Montmagny and Cap St. Ignace on the south shore of the St. Lawrence River in Québec, Canada. Year-to-year variation of production of the dominant species, Scirpus americanus Pers., was observed and related to variation in weather during the growing season. With the exception of Zizania aquatica L., relative production of the macrophytes for different parts of the marshes remained constant in successive years. A multiple regression procedure was used to establish the relationship between production and a series of independent variables including biotic (goose use and plant competition) and abiotic factors (submersion, substrate hardness, soil texture and sedimentation). A lower percentage of organic matter in the soil and a firm substrate were associated with a greater production of S. americanus. Accretion of sediments was positively correlated with the production of S. americanus and Sagittaria spp., whereas the percentage of time of submersion was negatively related with production of Sagittaria spp., Eleocharis spp. and Scirpus torreyi Olney. Competitive interference was apparent between S. americanus and S. torreyi and between Eleocharis spp. and Zizania spp. No measured abiotic characteristic of the marsh explained the variation of Zizania production.     

Molecular characterization, polymorphism and association study of lysozyme gene with milk production and somatic cell trait in Bos indicus × Bos taurus cattle

Lysozyme, an anti-bacterial enzyme, is mostly found in the body fluids, various tissues and secretions of animals and humans, and confers immunity against a wide range of bacterial species. The present study was carried out to elucidate the gene sequence of this enzyme in Indian Sahiwal × Holstein Friesian crossbred cattle and to explore the polymorphism of the gene as well as their association with milk production and somatic cell traits. The total length of lysozyme cDNA was found to be of 447 bp. The similarity with Bos taurus, human, pig, monkey, gorilla, mice, rat, chicken, dog and sheep was estimated as 99.1%, 85%, 81.0%, 85.2%, 84.3%, 77.9%, 77.9%, 41.4%, 40.5% and 24.6%, respectively. Polymorphism study of two fragments, extended exon1 including promoter, exon1 and partial intron1 (268 bp), and extended exon2 including partial intron1 and 2, and exon2 region (287 bp) of milk lysozyme gene was carried out by employing single-stranded conformation polymorphism (SSCP). In the extended exon1 fragment, three alleles namely A, B and C with frequencies of 0.59, 0.28 and 0.12 were observed while in the exon extended fragment, three different alleles - P, Q and R with respective frequencies of 0.61, 0.38 and 0.01 - were determined in Indian Sahiwal × Holstein Friesian cross. A total of eight haplotypes were found in this population where the most predominant one was h1 (0.52). Genotypes of exon1 extended fragment showed significant association with total milk yield, daily milk yield, peak yield and somatic cell score at P < 0.05 while that of exon2 extended fragment had significant correlation with only total lactational milk yield. Haplotype combinations also revealed significant association with total milk production where h1h1 homozygous showed highest yield during first lactation.