Calf Production Research Articles

Diet Supplementation With Pomegranate Peel Extract Altered Odorants Emission From Fresh and Incubated Calves' Feces

Emissions of odorous volatile organic compounds (VOCs) from livestock manure are of increasing environmental concern. Recent approaches in cattle nutrition and health make use of Mediterranean fruit byproducts, such as concentrated pomegranate peel extract (CPE) that carry antioxidant activities, which in turn may alter manure properties. This study explored the effect of CPE on odorants emission from beef calves feces. Fourteen calves were randomly assigned to control (n=7) and pomegranate (n=7) treatments. The latter was supplemented with 4% CPE in milk until weaning at the age of 60d. Following weaning, 4% CPE was added to calves ration, on dry matter basis. The control treatment received only milk or solid feed, respectively. Fresh feces of the four treatments (control/pomegranate; before/after weaning) were sampled twice, 2-3w before and 4-5w after weaning, and then incubated (28°C) for 0, 7, 14, and 30d. Sub-samples were placed in a flux chamber (37°C) and VOCs collected on thermal desorption (TD) tubes followed by TD-GC-MS analysis. In all treatments, flux quantities followed the general order of volatile fatty acids (VFAs) > alcohols > phenolic & aromatic > sulfuric > esters > aldehydes. Total VOCs, especially VFA fluxes, peaked on day 7 in correspondence with pH dynamics. The fractional contribution of alcohols, phenolic & aromatic and sulfuric VOCs generally increased during incubation. After weaning, short-chain VFAs flux was 5.2 times higher and the pH was 1.26 units lower in the pomegranate treatment (average on days 7&14), suggesting increased fermentation due to possible effect of CPE on gastrointestinal microflora. An automated ribosomal intergenic spacer analysis of fresh and incubated fecal DNA confirmed association between microbial fingerprinting and short chain VFAs, phenolic and sulfuric VOCs. Odorants emission after weaning, expressed as odor activity values, was 2 times higher in the pomegranate treatment (average on days 7&14) and generally dominated by VFAs, while in other treatments the contribution of phenolic and sulfuric odors increased as incubation proceeded. In conclusion, diet supplementation with CPE may be adopted with the purpose of increasing calves health and production, but it may alter odor characteristics of feces and increase feedlot nuisance if not managed properly.

Lifetime calf production distribution and effect of genetic and non-genetic factors on total herd life in Phule Triveni crossbred cattle

Lifetime calf production distribution and effect of genetic and non-genetic factors on total herd life in Phule Triveni crossbred cattle

381 The Nebraska Ranch Practicum: An Insight into Cow and Calf Production from Varying Precipitation and Two Weaning Dates.

381 The Nebraska Ranch Practicum: An Insight into Cow and Calf Production from Varying Precipitation and Two Weaning Dates.

ПРОДУКТИВНЫЕ КАЧЕСТВА БЫЧКОВ СИММЕНТАЛЬСКОЙ ПОРОДЫ ПРИ СКАРМЛИВАНИИ ИМ ПРОБИОТИКА ВЕТОСПОРИН СУСПЕНЗИЯ

The purpose of research is increase of beef productivity and beef quality of Simmental calves at introduc-tion in a diet of feeding different doses of the drug Vetosporin suspension. Of the half-yearly animals, 40 males were selected and formed into group IV for the experiment. The differences were only in feeding. The young were fed the studied additive Vetosporin suspension. In this case, the supplement was an addi-tion to the basic diet of animals of the experimental II-IV groups. The volume of the additive added was 0.1; 1.0; and 2 ml per 10 kg of live weight, respectively. Control group I, consumed exclusively a diet that does not contain an additive. Based on the results of the experiment at the age of 18 months. The prevalence of bulls of the experimental live weight over peers was observed, which was 4.4-25.3 kg (0.78-4.67%). The study of the studied indicators after control slaughter in the context of groups showed the superiority of bulls of experimental groups in all the periods studied. It is established that at the age of 15 months. The size of the removable live weight of the youngest of the control group was less by 8.0-19.7 kg (1.75-4.29%) than in the animals of the test groups. In this case, the leading position was occupied by the youngest of group III, the prevalence of which was 0.7-11.7 (0.14 -2.51%). It should be noted that after 3 months a simi-lar picture of the distribution of the studied quantities was observed. As for the output of carcass, we can note the following. Outsider among the animals of the experimental groups was the control group. So the bulls of group I were inferior to those who received the additive by 0.7-1.3%. At 18 months, as well as at 15 months, the dominant position was occupied by gobies of experimental groups. It should be noted that among the animals of the experimental groups the leading place was occupied by the bulls receiving the feed additive in a dose of 1.0 ml per 10 kg of live weight, that is, the youngest of the III group.

PRECOCIDADE DE PARTO NA ESTAÇÃO DE PARIÇÃO SOBRE A EFICIÊNCIA PRODUTIVA DE VACAS PRIMÍPARAS AOS 24 MESES DE IDADE

Resumo Objetivou-se verificar o efeito de dois períodos de parto, na estação de parição (precoces: setembro; e tardios: outubro), sobre a eficiência de 54 vacas Red Angus primíparas aos 24 meses de idade. As vacas foram mantidas em pastagem natural e cultivadas de Lotus corniculatus e Lolium multiflorum nos períodos pré e pós-parto, respectivamente. Utilizou-se inseminação artificial em tempo fixo, com dois protocolos, em intervalo de 30 dias. Realizaram-se diagnósticos de gestação 30 dias após cada protocolo. Bezerros de vacas paridas precocemente ganharam mais peso durante o aleitamento, sendo mais pesados ao desmame, quando comparados aos de vacas tardias, perfazendo maiores ganhos do conjunto vaca-bezerro durante a lactação (0,721±0,030 e 0,699±0,032 kg). O desempenho reprodutivo foi superior paras as vacas paridas precocemente nas duas sincronizações e no índice de prenhez total (86,2 e 52%). Vacas precoces na parição obtiveram maiores índices de produção de bezerros (161,5±3,2 e 92,5±3,5 kg), produção de bezerros/kg de vaca ao desmame (40,9±0,97 e 23,7±1,04 kg) e eficiência produtiva ao parto (34,3±1,25 e 20,8±1,35 kg). Vacas paridas precocemente são mais eficientes na produção de kg de bezerros/kg de vaca ao parto e ao desmame e, associando-se kg produzidos e prenhez subsequente, apresentam maior índice de produção de bezerros.

The effect of lung consolidation, as determined by ultrasonography, on first-lactation milk production in Holstein dairy calves

Bovine respiratory disease (BRD) is a complex disease process and many reports emphasize the negative implications of clinical BRD in dairy calves. Early diagnosis can be difficult because of inconsistent or absent clinical signs; however, the use thoracic ultrasonography has the potential to improve detection of respiratory disease. Earlier detection of BRD may result in actions to improve calf welfare and production. The objective of this prospective cohort study was to determine if lung consolidation (LC) in young dairy calves influenced age at first calving (AFC), first-lactation milk production, and survival to the end of first lactation. A total of 215 female calves from 3 dairy herds in southwestern Ontario were enrolled and assessed weekly during their first 8 wk of life for evidence of LC using thoracic ultrasonography (Ibex Pro, Loveland, CO). Consolidation was measured, using gridlines on the screen of the ultrasound, in the first 10 intercostal spaces on both sides of the thorax. Calves were considered LC positive if ≥3 cm of consolidated lung was present. Multivariable linear regression models were used to identify risk factors associated with AFC and first-lactation 305-d milk production. A survival analysis was conducted to determine differences in survival from enrolment until the end of first lactation between calves with and without consolidation. In the study population, the following calfhood conditions were detected: twins (4%; n = 8), diarrhea in the first 21 d of life (31%; n = 66), rib fractures (7%; n = 14), lung abscesses (3%; n = 6), and at least one diagnosis of LC (57%; n = 123). Overall, 7% (n = 15) of calves died, and 18% (n = 38) of animals were sold before the end of first lactation. The presence of LC, at least once in the first 8 wk of life, did not influence AFC, but did result in a 525 kg (95% confidence interval: -992.81 to -60.25) decrease in first-lactation 305-d milk production. No difference in survival was detected between LC groups. These results indicate that LC during the first 56 d of life has a long-term effect on dairy calves, manifested as reduced milk production during first lactation.

32 Effect of Exercise on Calf Productivity, Health and Behavior.

32 Effect of Exercise on Calf Productivity, Health and Behavior.

Effects of Topical Anaesthetic and Buccal Meloxicam Treatments on Concurrent Castration and Dehorning of Beef Calves.

Simple SummaryThe pain caused by surgical procedures performed routinely for managing livestock husbandry is recognised as a significant animal welfare issue for food security. In recent years, there has been progress encouraging the uptake of pain relief in extensively managed livestock operations, with research and development offering options for the practical delivery of anaesthetics and analgesics during these procedures. In Australia, topical anaesthetic and buccal meloxicam treatments are now commercially available for use during routine surgical husbandry procedures of lambs and calves. A study to assess the effect of these treatments on weight gain and behavioural variables following concurrent surgical castration and amputation dehorning in beef calves is reported. Results showed that a combination of topical anaesthetic and buccal meloxicam appeared to reduce pain following castration and dehorning, with improved weight gain and increased lying activity in the first few days following the procedures. In addition, some individual behaviours expressed by the calves on the day of treatment suggested pain was relieved by topical anaesthetic and buccal meloxicam, although further clarification of this observation is required. These findings demonstrate that provision of topical anaesthetic and buccal meloxicam to beef calves undergoing surgical castration and amputation dehorning can result in improved animal welfare and production.The use of pain relief during castration and dehorning of calves on commercial beef operations can be limited by constraints associated with the delivery of analgesic agents. As topical anaesthetic (TA) and buccal meloxicam (MEL) are now available in Australia, offering practical analgesic treatments for concurrent castration and dehorning of beef calves, a study was conducted to determine their efficacy in providing pain relief when applied separately or in combination. Weaner calves were randomly allocated to; (1) no castration and dehorning/positive control (CONP); (2) castration and dehorning/negative control (CONN); (3) castration and dehorning with buccal meloxicam (BM); (4) castration and dehorning with topical anaesthetic (TA); and (5) castration and dehorning with buccal meloxicam and topical anaesthetic (BMTA). Weight gain, paddock utilisation, lying activity and individual behaviours following treatment were measured. CONP and BMTA calves had significantly greater weight gain than CONN calves (p < 0.001). CONN calves spent less time lying compared to BMTA calves on all days (p < 0.001). All dehorned and castrated calves spent more time walking (p = 0.024) and less time eating (p < 0.001) compared to CONP calves. There was a trend for CONP calves to spend the most time standing and CONN calves to spend the least time standing (p = 0.059). There were also trends for the frequency of head turns to be lowest in CONP and BMTA calves (p = 0.098) and tail flicks to be highest in CONN and BM calves (p = 0.061). The findings of this study suggest that TA and MEL can potentially improve welfare and production of calves following surgical castration and amputation dehorning.

Efficacy of Oral Administration of Sodium Iodide to Prevent Bovine Respiratory Disease Complex.

BackgroundThe prevention of bovine respiratory disease complex (BRD) in beef cattle is important to maintaining health and productivity of calves in feeding operations.ObjectiveDetermine whether BRD bacterial and viral pathogens are susceptible to the lactoperoxidase/hydrogen peroxide/iodide (LPO/H2O2/I−) system in vitro and to determine whether the oral administration of sodium iodide (NaI) could achieve sufficient concentrations of iodine (I) in the respiratory secretions of weaned beef calves to inactivate these pathogens in vivo.AnimalsSixteen weaned, apparently healthy, commercial beef calves from the University of Missouri, College of Veterinary Medicine teaching herd.MethodsIn vitro viral and bacterial assays were performed to determine susceptibility to the LPO/H2O2/I− system at varying concentrations of NaI. Sixteen randomly selected, healthy crossbred beef weanlings were administered 70 mg/kg NaI, or water, orally in a blinded, placebo‐controlled trial. Blood and nasal secretions were collected for 72 hours and analyzed for I− concentration.ResultsBovine herpesvirus‐1, parainfluenza‐3, Mannheimia haemolytica and Bibersteinia trehalosi were all inactivated or inhibited in vitro by the LPO/H2O2/I− reaction. Oral administration of NaI caused a marked increase in nasal fluid I concentration with a C max = 181 (1,420 μM I), T12, a sufficient concentration to inactivate these pathogens in vitro.Conclusions and Clinical ImportanceIn vitro, the LPO/H2O2/I− system inactivates and inhibits common pathogens associated with BRD. The administration of oral NaI significantly increases the I concentration of nasal fluid indicating that this system might be useful in preventing bovine respiratory infections.

Effect of a Non-Specific Immune Stimulant (Amplimune™) on the Health and Production of Light Feedlot Calves

An increasing concern from both producers and consumers regarding the overuse and misuse of antibiotics leading to the development of antibiotic resistant pathogens dictates the need for new research objectives These new objectives should be directed towards exploring different management practices and the use of antibiotic alternative products to treat or prevent disease in cattle and other food producing animals The main objective of this pilot study was to determine if a bovine immunotherapeutic Amplimune derived from Mycobacterium cell wall fraction MCWF decreases the incidence and severity of clinical conditions that require antimicrobial treatments thus reducing the cost of treatment and improving weight gain in young calves entering the feedlot Four hundred and eighty Holstein steer calves were transported from a large commercial ranch in New Mexico to a feedlot in California Twenty four hours following arrival calves were randomly assigned to one of three treatment groups control MCWF and MCWF and allocated to feedlot pens Animals in MCWF and MCWF groups received either mL or mL of Amplimune subcutaneously while the animals in the control group were untreated For the purpose of the study metaphylactic use of antibiotics was omitted at the time of arrival Animals were monitored for days and information on the health status clinical conditions treatments and body weights were collected and subjected to further analysis Groups that received Amplimune had and less treated animals compared to controls resulting in calculated savings of USD and USD for the MCWF and MCWF groups respectively In addition calves treated with Amplimune gained a total of lbs and lbs more Overall there was a significant beneficial effect observed with regards to morbidity average weight gain and medical cost per head for both MCWF groups when compared to controls Results from this pilot study suggest Amplimune as a substitute for antibiotic prophylactic treatment in calves entering feedlot

Performance Efficiency of Pasture-raised Primiparous Beef Cows of Three Different Biotypes and Two Milk Production Levels

Background: Productivity and efficiency of beef production systems should be estimated based on cow size, calf growth rate and cow reproduction rate, which are critical factors for the evaluation of production characteristics of beef cattle of different biological types. One of the ways to measure beef cow productivity is based on the ratio of calf weaning weight to cow weight. The purpose of this study was to evaluate the performance and reproductive efficiency of primiparous beef cows of three different biotypes and two milk production levels, from calving to weaning, in pasture-raised beef systems. Materials, Methods &amp; Results: Forty-two primiparous Angus cows were classified according to body weight at calving, as follows: Heavy (431 kg); Medium (388 kg); and Light (348 kg). Cow efficiency as a function of biotype was evaluated at two different moments: calving and weaning, based on the ratio of calf weight to cow weight*100 (in kilograms). Calf production efficiency was determined based on the ratio of calf weaning weight (CWW) to cow pregnancy rate (PR), resulting in the calf production index = kg of weaning calves per cow (CWW*PR/100). The experimental design was a completely randomized factorial 3 x 2 x 2 design (three biotypes x two calf sexes x two milk production levels). The results were subjected to ANOVA and F-test. The Light and Medium cow groups produced more (P &lt; 0.05) kilograms of calf per kilogram of cow (16.0 and 15.1 kg, respectively) than the Heavy group (14.0 kg). Light cows showed lower (P &lt; 0.05) milk production and, as a result, lighter (P &lt; 0.05) calves at weaning (151.9 ± 4.3 kg) than Medium and Heavy groups, 166.0 ± 3.7; 166.5 ± 4.0 kg, respectively. At beginning of the breeding season, cows of the Lower milk production group were on average 27.49 kg heavier than cows in the Higher milk production group. There was an interaction (P &lt; 0.05) between total milk production and calf sex on characteristics of performance in calves and performance efficiencies of the system. Light and Medium cows showed 51 and 25 kg total weight gain from calving to weaning, corresponding to 14.7 and 6.4% of body weight, respectively. The Heavy group, however, showed a 3 kg loss (0.5% of body weight) during the same period. Discussion: A higher growth rate was observed in the pre-weaning period of the calves of heavy cows; as a result, these calves were heavier at weaning. To achieve this result, heavier cows may compensate this higher nutritional requirement using body reserves. This biological adjustment may not be economically efficient, since the subsequent reproduction of these cows could be impaired by increases in milk production. Therefore, the target cow in a pasture-raised beef system is one whose low nutritional requirements enable her to produce milk, resulting in heavier calves, and whose physiological conditions enable her to conceive again during the breed season. Light cows can be considered an efficient group, since their pregnancy rate enabled them to create a positive difference for the group, notwithstanding their lower milk production and lighter calves (P &lt; 0.05) at weaning. This tendency is expected, since increased growth rates are associated with a decrease in puberty and early finishing age. It is essential to select animals according to their efficiency in order to reduce the cow’s requirements, since this favors the increased productivity of cows of lower maintenance cost in relation to their body weight, leading to higher biological and economic efficiency in the beef production system. In conclusion, because of their lower nutritional requirements, cows of small and moderate biotypes and lower total milk production are more efficient than cows of larger biotypes and higher milk production in pasture-raised beef systems.

77 Monozygotic Twin Calves Production by Blastomere Separation Technique with Commercial Well-of-the-Well Culture Dish

Monozygotic twin bovine embryos can be produced by blastomere separation of 2-cell embryos and commercial well-of-the-well (WOW) culture dish (Hashiyada et al. 2016 Reprod. Fertil. Dev. 28, 178) obtaining 60% and 48% of blastocyst formation and monozygotic blastocyst pairs, respectively. The present study was conducted to evaluate the fertility of blastocysts derived from this production system in Japanese Black beef cattle. Embryos were produced using oocytes collected by ovum pick-up technique. TCM-199 supplemented with 5% calf serum (CS), Brackett-Oliphant solution supplemented with 10 mg mL−1 BSA, and CR1aa containing 5% CS, were used for each culture step: in vitro maturation, fertilization, and culture (IVM,IVF, and IVC). Two-cell stage embryos were obtained 24 to 27 h post-insemination. Zonae pellucidae were removed by exposure to 0.25% pronase. Then, embryos were separated into blastomeres by gentle pipetting in IVC medium. Each blastomere was introduced into a single conical microwell of 25 wells, each having a diameter and depth of ~287 μm and 168 μm (Dai Nippon Printing, Tokyo, Japan). Blastomeres in wells were cultured covered with a droplet of 2.5 μL of IVC medium/well. The developed blastocysts in pairs on 7 days post-insemination were used for transfer. Single embryos of monozygotic twin embryos were transferred to Japanese Black cattle with a generally small body frame to produce twin calves from a set of recipients. Twin embryos were transferred in pairs to unilateral of uterus of non-lactating Holstein cows. Pregnancy and twin pregnancy were determined at 30 days of gestation by ultrasonography and were reconfirmed at 60 days with detection of fetal loss. Statistical significance was analysed by Fisher’s exact test. There was no significant difference in pregnancy rate or twin pregnancy rate between single embryo transfer (7/14, 50% and 2/7, 28.6%) and twin embryo transfer (9/21, 42.9% and 4/21, 19%). In either transfer method, fetal loss was not observed in diagnosis carried out at 60 days by ultrasonography. To date, 2 pairs of twin calves have been obtained from twin pregnant cows by twin embryo transfer within the normal range of gestation length (286 and 288 days) and birth weight (31-40 kg). These results indicate that blastocysts developed from blastomeres separated from 2-cell embryos by culturing with commercial WOW culture dish had fertility similar to that of intact embryos derived from standard in vitro culture and further demonstrate the possibility of production of normal twin calves.

ANÁLISE DE CUSTOS, RECEITAS E PONTO DE EQUILÍBRIO DOS SISTEMAS DE PRODUÇÃO DE BEZERROS NO RIO GRANDE DO SUL

Resumo O objetivo deste trabalho foi realizar a avaliação da viabilidade econômica de um modelo tradicional de produção de bezerros de corte em sistema extensivo, desenvolvido nas condições de receitas obtidas e gastos de insumos recomendados para as condições de produção normais no estado do Rio Grande do Sul. Foram realizadas duas entrevistas em propriedade rurais para coleta de dados referentes aos gastos de recursos, estruturas disponíveis para o sistema de produção e taxas de ocupação das áreas de pastejo. Os resultados mostraram que os principais custos operacionais da atividade foram a mão de obra e a alimentação do rebanho. Nos custos de oportunidade a terra representou a maior proporção (52,0%) do custo total. Os custos fixos foram maiores do que os custos variáveis (61,7% vs 38,3%). As margens bruta e líquida indicaram que a atividade é sustentável, mas economicamente o ponto de equilíbrio de natalidade (85,0%) esteve acima dos índices médios relatados pela literatura, e valores negativos para rentabilidade (-19,0%) e lucratividade (-23,2%). Concluiu-se que a viabilidade dos sistemas de produção estudados nesta pesquisa podem ser obtidos a partir da otimização de tecnologias de produção ou a redução dos custos fixos sem alterar as receitas.

Fitness correlates of age at primiparity in a hunted moose population.

Trade-offs between fitness-related traits are predicted from the principle of resource allocation, where increased fecundity or parental investment leads to reduced future reproduction or survival. However, fitness traits can also be positively correlated due to individual differences (e.g. body mass). Age at primiparity could potentially explain variation in individual fitness either because early primiparity is costly, or it may lead to higher lifetime reproductive success. Based on long-term monitoring and genetic parentage assignment of an island population of moose, we quantified reproductive performance and survival, and examined whether early maturing females have higher total calf production than late maturing females. We explored if harvesting of calves affected the subsequent reproductive success of their mothers, i.e. also due to a post-weaning cost of reproduction, and whether there are any intergenerational effects of female reproductive success. There was a positive relationship between current and future reproduction. The probability to reproduce was lower for females that were unsuccessful the year before, indicating a strong quality effect on productivity. Females that started to reproduce as 2-year olds had a slightly higher total calf production compared to those starting at age three or four. High-performing mothers were also correlated with daughters that performed well in terms of reproductive success. Our results suggest that the observed individual heterogeneity in fitness could be associated with differences in age at primiparity. This heterogeneity was not affected by reproductive costs associated with tending for a calf post-weaning.

EFFECT OF DIETARY CONCENTRATE TO ROUGHAGE RATIO ON NUTRIENT DIGESTIBILITY, RUMEN FERMENTATION, GROWTH PERFORMANCE AND SERUM ACUTE PHASE PROTEIN IN GROWING BUFFALO CALVES

This study was accomplished to designed to assess the appropriate concentrate: roughage ratio (C:R) ratio for better nutrient digestibility, rumen fermentation patterns, healthy and economic beef production in Egyptian buffalo calves. Sixteen buffalo calves aged about 18-20 months of 292.5±4.7 kg average body weight were randomly assigned into four groups of 4 animals each. The treatment diets were composed of four concentrate: roughage (C:R) ratios (80:20, A; 75:25, B; 60:40, C; and 55:45, D). The results revealed that increasing in the proportion of concentrate in the diet significantly (p <0.05) increased the digestibility of dry matter (DM), organic matter (OM), crude protein (CP), crude fiber (CF), ether extract (EE), nitrogen free extract (NFE) and the total digestible nutrients (TDN). Ruminal concentration of both volatile fatty acids (VFA) and ammonia nitrogen were increased linearly with increasing the dietary concentrate portion (60, 75 and 80), however the rumen pH were decreased (P<0.01) with increasing the concentrate level in the diet. In addition, increasing the concentrate proportion increased the dry matter intake of feed, average daily gain, final body weight; and feed cost per kg body weight. Serum, glucose, and acute phase protein were increased by increasing the dietary concentrate portion. Feeding diet containing 60% concentrate showed better performance and economic efficiency per kg body weight gain when comparing with diet containing 75 % and 80 % concentrates levels. This study suggested that the diet consisting of 60: 40 concentrate: roughage ratio could be considered as the optimum diet for growing buffalo calves for better performance, efficient feed utilization, economic feed efficiency and low risk of sub-acute ruminal acidosis.

Can farmers mitigate environmental impacts through combined production of food, fuel and feed? A consequential life cycle assessment of integrated mixed crop-livestock system with a green biorefinery

This study evaluates environmental impacts of an integrated mixed crop-livestock system with a green biorefinery (GBR). System integration included production of feed crops and green biomasses (Sys-I) to meet the demand of a livestock system (Sys-III) and to process green biomasses in a GBR system (Sys-II). Processing of grass-clover to produce feed protein was considered in Sys-II, particularly to substitute the imported soybean meal. Waste generated from the livestock and GBR systems were considered for the conversion to biomethane (Sys-IV). Digestate produced therefrom was assumed to be recirculated back to the farmers' field (Sys-I). A consequential approach of Life Cycle Assessment (LCA) method was used to evaluate the environmental impacts of a combined production of suckler cow calves (SCC) and Pigs, calculated in terms of their live weight (LW). The functional unit (FU) was a basket of two products “1kgLW-SCC+1kgLW-Pigs”, produced at the farm gate. Results obtained per FU were: 19.6kg CO2 eq for carbon footprint; 0.11kg PO4 eq for eutrophication potential, −129MJ eq for non-renewable energy use and −3.9 comparative toxicity units (CTUe) for potential freshwater ecotoxicity. Environmental impact, e.g. greenhouse gas (GHG) emission was primarily due to (i) N2O emission and diesel consumption within Sys-I, (ii) energy input to Sys-II, III and IV, and (iii) methane emission from Sys-III and Sys-IV. Specifically, integrating GBR with the mixed crop-livestock system contributed 4% of the GHG emissions, whilst its products credited 7% of the total impact. Synergies among the different sub-systems showed positive environmental gains for the selected main products. The main effects of the system integration were in the reductions of GHG emissions, fossil fuel consumption, eutrophication potential and freshwater ecotoxicity, compared to a conventional mixed crop-livestock system, without the biogas conversion facility and the GBR.

Altitude effects on technology and productivity of small bovine farms (milk meat) in Veracruz (Gulf of Mexico).

The dual-purpose bovine system represents 98.4% of the bovine livestock of Veracruz, the main cattle-producing state of Mexico. This system supplies calves to meat companies, a sector in which Veracruz has been the national leader in the last decade. The objective of the present study was to analyze the effect of the altitudinal zonation of farms on livestock technology and productivity in a microbasin of the Gulf of Mexico where small farms predominate. Structured interviews were applied to producers located in three altitudinal zones (at average altitudes of 50, 140, and 450m, respectively, for lower, middle, and upper zones). Sample size was 135 farms having similar land surface (within a range of 15-22ha). The results indicated multiple differences among farms located in the three zones. Farms in the middle and lower zones presented higher productive indicators than those in the upper zone. Differences in herd structure and management resulted in important differences in productivity, income, and profits in milk and calf production. We concluded from this study that altitudinal zonation in Veracruz had a clear effect on the differentiation of small farms, which are representative of dual-purpose cattle. The upper zone performs cattle activity under conditions with greater disadvantages in the analyzed region.

Short communication: Effect of age at group housing on behavior, cortisol, health, and leukocyte differential counts of neonatal bull dairy calves

To determine the effect of age at grouping on behavior, health, and production of dairy bull calves, 90 Holstein-Friesian bull calves were housed in individual pens until moved to 1 of 3 treatments. Calves were housed in groups of 3 calves at 3 d old (GH3), 7 d old (GH7), or 14 d old (GH14) until 7 wk of age. Ten groups of 3 calves for each treatment were used, with 5 pens/treatment in each of 2 replications (10 pens/treatment, 3 treatments, 3 calves/treatment; 90 calves total). Direct behavioral observations using instantaneous scan sampling every 10 min were conducted twice per week for 7 wk. At the same times, video data were recorded for continuous observations at feeding time to observe the overall activity of group-housed calves. Hip height, heart girth, and health scores were recorded weekly and body weight was recorded at the start and end of the study. Calves in GH3 spent more time playing and but more time cross-sucking and displacing other calves from milk bottles. Calves engaged in social interaction as early as 3 d of age, and social interactions between 3 to 6 wk of age increased markedly. Calves housed in GH14 vocalized more than did calves in GH7 and GH3. No difference was found between treatments in growth performance. Calf fecal, cough, and nasal and ocular discharge scores, differential leukocyte counts, and plasma cortisol concentrations were not affected by age at grouping. However, during the first week of grouping, when calves were moved from individual pens to group pens, some calves were unable to find their milk bottles and required guidance. In conclusion, these data show no adverse effects on health or performance and some benefits on social behavior for early (d 3) grouping of calves.

Prevalence and Transmission of Antimicrobial Resistance in a Vertically Integrated Veal Calf Production System.

Transmission of antimicrobial resistance (AMR) from animal production systems to humans through the food supply is a public health concern. Currently, little is known about the prevalence of AMR among veal calves in the United States. Therefore, the objective of this prospective cohort study was to estimate the prevalence of AMR and multidrug resistance (MDR) among Escherichia coli within a vertically integrated production system. In addition, this study aimed to identify genes associated with phenotypic resistance to third- and fourth-generation cephalosporins (3GC and 4GC). Calves from four veal cohorts were randomly sampled resulting in a total of 166 farm fecal samples, 159 harvest fecal swabs, 164 preevisceration swabs, and 122 final carcass swabs. The prevalence of MDR among random-pick E. coli isolates recovered from the respective samples was 97% (161/166), 35% (55/159), 61% (51/84), and 24% (5/21). A selective isolation protocol found cefotaxime (a 3GC)-resistant isolates in 91% (127/140) of farm fecal samples, 34% (55/164) of preevisceration swabs, and 19% (23/122) of final carcass swabs tested. Isolates resistant to cefepime, a 4GC, were found among 24% (33/140), 6.7% (11/164), and 0.8% (1/122) of the same, respective samples. Isolates resistant to ciprofloxacin, a fluoroquinolone, were recovered from 75% (73/98) of farm fecal samples, 23% (38/164) of preevisceration swabs, and 6.6% (8/122) of final carcass swabs. The blaCMY-2 and blaCTX-M resistance genes were found in 89% (93/105) and 100% (42/42) of tested subsets of 3GC- and 4GC-resistant isolates, respectively. Pulsed-field gel electrophoresis (PFGE) analysis conducted on 3GC- and fluoroquinolone-resistant isolates showed three indistinguishable PFGE patterns from cefotaxime-resistant isolates recovered at farm and from two preevisceration carcass swabs. Although the prevalence of resistance declined between initial farm fecal samples and final carcass swabs, resistant bacteria recovered from carcasses illustrate the potential transmission of AMR to the human food supply.

Validation of commercial luminometry swabs for enumeration of total bacteria and coliform counts in colostrum feeding equipment

Colostrum feeding is an integral component of neonatal calf care with many effects on calf health and productivity, yet failure of passive transfer remains common on many dairy farms. A sufficient quantity and quality colostrum must be fed quickly to the newborn calf while minimizing bacterial contamination. Colostrum with a total bacteria count (TBC) &gt;100,000 cfu/ml may impair IgG absorption and contribute to disease. Adenosine triphosphate ATP bioluminescence swabs offer a potential rapid calf-side alternative to traditional bacterial culture. The reagents in the swabs produce a light-generating reaction when in contact with bacterial ade¬ nosine triphosphate, which is quantified in relative light units (RLU) with a luminometer. The objective of this study was to validate the HygienaTM AquaSnap (AS), SuperSnap(SS), PRO-Clean (PC) and MicroSnap (MS) swabs as well as visual hygiene assessment for detection of elevated bacterial counts in or on colostrum-feeding equipment.