Management practices and risk factors for morbidity and mortality in Minnesota dairy heifer calves

This prospective study involved 845 Holstein heifer calves born during 1991 on 30 dairy farms in southeast Minnesota. The objectives of the part of the study reported here were to examine relationships between management practices and incidence of morbidity and mortality at both herd and individual-calf levels. A survey administered by the investigators identified the herd management practices. Check-off forms completed by cooperating producers captured the individual-calf risk factors. Data collected included events surrounding each calf's birth as well as treatments and disease diagnoses for each heifer calf. Outcomes of interest were any occurrence of enteritis, pneumonia, or death between birth and 16 weeks of age. Time, place and date of birth, ease of birth, colostrum administration and any other treatments at birth, housing and any other treatments were the risk factors of interest. The overall morbidity rate for the study was 0.2 calves treated per 100 calf-days at risk (range 0-0.8, standard deviation 0.2), while the rates for scours and pneumonia were 0.15 cases per 100 calf-days at risk (0-0.7, ± 0.2) and 0.10 (0-0.7, ± 0.2) cases per 100 calf-days at risk, respectively. The mortality rate for the study period was 0.08 deaths per 100 calf-days at risk (0-0.3, ± 0.08); 64 heifers (7.5%) died during the study. Mean average daily weight gains for heifers from birth to 16 weeks of age was 0.82 kg day⁻¹ for all farms (0.45–1.1, ± 0.2). In general, stated herd management practices were practiced at the individual-calf level. Several herd management practices altered the outcomes of interest. For example, the feeding of a coccidiostat to preweaned calves increased the herd risk of pneumonia (relative risk, 3.38; 95% CI 1.34–8.50). The feeding of a vitamin A-D-E supplement to preweaned calves exerted a protective effect against scours (0.35, 0.13–0.93). Managing group pens for weaned calves in an ‘all-in, all-out’ fashion rather than in a continuous flow system contributed to a farm having an average daily rate of gain that was above the median (3.06, 1.34–6.97). The Cox proportional hazards model was used to describe relationships between risk factors and the outcomes of interest. Calves that required assisted delivery were at an increased risk of developing enteritis sooner than those that were born without assistance. No other risk factors had a significant effect.     

Beef quality traits of heifer in comparison with steer,bull and cow at various feeding environments

The present review has been focused largely on the sex type differences in beef quality among heifers, cows, steers and bulls in various feeding environments. Genetic groups, feeding systems and gender are the major factors that change carcass characteristics and fatty acid profiles of cattle. Studies identified that heifer beef has super characteristics in eating quality and a better healthy composition in fatty acids than steer, cow and bull. Diet influences the variation of fatty acid profile; particularly the level of polyunsaturated fatty acids (PUFA) interacts with breed and sex. Animals finished in pasture systems were reported to show better ratios of PUFA/ saturated fatty acids and n‐6/n‐3. Carcasses of roughage‐fed beef are lighter and have less marbling and lower quality grades but have higher cutability than carcasses of grain‐fed bulls. Heifers and cows are reported to deposit more fat than steers and bulls. Among males, lower production of testosterone by steers favors more fat thickness compared with bulls. Marbling greatly varies among cattle belonging to different sexes, and particularly, females have genetic makeup that efficiently controls deposition. The current review identified that heifers can be a premium beef brand, while steer beef currently take a large part of market share across the world.     

Surgery and radiotherapy for management of compound odontoma in a heifer

A 1 1/2-year-old Holstein heifer was examined because of a rostral mandibular mass. On the basis of radiographic and histopathologic findings, a diagnosis of compound odontoma was made. The heifer was successfully treated with surgery and irradiation.     

Beef heifer production as affected by indoor feed intensity and slaughter age when grazing semi-natural grasslands in summer

Only limited knowledge exists on how to produce high-quality beef carcasses when the cattle also are grazing semi-natural grasslands for nature conservation purposes. The objectives of the two factorially-designed trials were to determine the effects of indoor feed intensity (low vs. high) and slaughter age (18 vs. 22 months) on performance and carcass quality of beef heifers, raised from weaning until slaughter and grazing semi-natural grasslands during growing seasons. In the first trial, 56 Charolais heifers were used of which 28 were fed only grass-clover silage ad libitum (low; CL), and another 28 heifers were fed 2.0 kg of grain daily in addition to the silage (high; CH). In the second trial, 28 Angus heifers were fed grass-clover silage at 80% ad libitum (low; AL), whereas another 28 heifers were fed silage ad libitum (high; AH). According to a national nature conservation score, the grazing pressure on the semi-natural grassland was classified as having been satisfactory to maintain the floristic diversity as no litter had been accumulated onto the sward. From weaning until slaughter, no difference in average daily gains (ADG) was found between the CH and the CL, whereas the AH had higher ADG than the AL (693 vs. 573 g, P < 0.001). Heifers in both trials had higher carcass weights and more fat, Charolais heifers also had better conformation and Angus heifers had higher dressing percentage at 22 months than at 18 months of slaughter age (P < 0.05). In conclusion, carcass traits in both trials were more affected by slaughter age than by feed intensity and desirable grazing effects were achieved on the pasture.     

公猪精子活力和形态对受精能力的重要性

公猪的精子活力和形态评定是人工授精站的日常基本工作。本文综述了精子活力和形态评定方法的实质性进展,以及精子形态与受精能力之间的相关性。精子形态是除活力之外一个重要的受精能力关联参数,在人工授精中需要被充分考虑。     

Long-term effects of good handling practices during the pre-weaning period of crossbred dairy heifer calves

The aim of this study was to determine whether applying good practices of handling during the pre-weaning period have long-term effects on behavioral and physiological indicators, health status, and average daily gain (ADG) of crossbred Bos taurus × Bos indicus heifer calves. During the pre-weaning period, 98 crossbred of Holstein × Gir heifer calves were allotted into three treatments: (1) good practices of handling + brushing (GPB; n?=?25), (2) good practices of handling (GP; n?=?25), and (3) control (n?=?48). Every 2 months, four evaluation periods (EV₁ to EV₄) were conducted to record data. Behavioral indicators comprised time to drive (TD), flight speed (FS), flight distance (FD), and composite reactivity score (CRS). Physiological indicators of acute stress during handling comprised respiratory and heart rates. Health status comprised data regarding occurrence of most common diseases (i.e., pneumonia and anaplasmosis). Collected data were analyzed by using a linear mixed model for repeated measures, Tukey’s test, and chi-squared procedures. Treatment influenced (P?<?0.05) TD, FS, and FD but not CRS (P?=?0.78). From EV₁ to EV₃, the control calves had the lowest TD. The GPB group had lower FS than the control but did not differ from GP. The GPB group had lower FD means than the other two groups in EV₂, EV₃, and EV₄. No differences (P?>?0.05) due to treatment were observed on heart and respiratory rates, ADG, or occurrence of pneumonia and anaplasmosis. It was concluded that adoption of good practices of handling during pre-weaning period may lead to long-term positive effects.     

Developing group practices: a management challenge

SUMMARY: The advantages and disadvantages of forming larger professional practices are often debated. This paper reports an exploration of the issues through three case studies involving clusters of Sydney general medical practitioners who had expressed a desire to amalgamate their solo or small group practices. Their most frequently stated goals were to reduce financial overheads, to improve the range of services offered to their patients and to improve the opportunities for recreational and study leave. Several barriers to successful amalgamation were identified, and methods of overcoming these were explored. Practices can successfully amalgamate, but only where there is a group of like-minded general practitioners who are willing to invest time to achieve mutually agreed objectives. Amalgamation will not be appropriate in all circumstances. Larger group practices should benefit from the employment of a professional practice manager. These findings may be relevant to veterinary and dental practices.     

高尔夫球场草坪的养护管理

高尔夫球场的养护主要包括草坪的水肥管理、病虫害管理等方面.针对这些问题提出了具体的养护管理措施,并拟定了高尔夫球场的周年管理计划.     

高尔夫球场的草坪管理和维护

高尔夫球场的维护主要包括草坪的水肥管理，病虫害管理以及常见杂草的防除等方面。草坪的水肥管理主要包括草坪的土壤条件、草坪施肥的目的、种类及方法，草坪的病虫害管理主要包括高尔夫球场病虫害预测预报体系的建立以及高尔夫球场的草坪常见病虫害的发生特点及防治方法。     

高尔夫球场的草坪管理和维护

高尔夫球场的维护主要包括草坪的水肥管理、病虫害管理以及常见杂草的防除等方面.草坪的水肥管理主要包括草坪的土壤条件、草坪施肥的目的、种类及方法;草坪的病虫害管理主要包括高尔夫球场病虫害预测预报体系的建立以及高尔夫球场的草坪常见病虫害的发生特点及防治方法.     

关于退牧还草的意义和技术标准问题探讨

退牧还草是一项长期而又复杂的系统工程,需要统筹考虑、科学规划、合理安排.但各地在实际操作中对究竟怎么退、如何退,缺乏规范和技术标准,这集中表现在没有明确什么样的草地需要禁牧、什么样的草地需要休牧、什么样的草地需要轮牧等问题上.禁牧、休牧和轮牧的工程标准和技术措施缺乏,给当前正在进行的退牧还草工作带来很多混乱和困难.因此,规范退牧还草的技术标准是当前退牧还草工作首先要解决的问题.     

Soil fertility management in pasture small-plot trials: potential pitfalls

Small-plot cutting trials are of particular importance in research relating to intensive pastures. Undetected changes in soil fertility during the course of experimentation may detract from the validity of results in trials of this kind. Information from field trials conducted in KwaZulu-Natal during the past two decades are used to illustrate the potential impact of soil fertility aspects in small-plot cutting trials. A major potential pitfall is the underestimation of potassium (K) depletion accompanying the removal of herbage at harvesting. In an Italian ryegrass trial 518 kg K ha^?1 was removed in harvested material in a single season. Failure to compensate (by fertilizer topdressings) for removals of K may result in growth, particularly in the more favourable treatments, being inadvertently restricted. Soil acidification during the course of experimentation is a second factor which may threaten the usefulness of data from cutting trials. Acidification is promoted by the application of relatively high rates of N fertilizers; in this context, variable acidification where N fertilization is a factor in trials warrants particular attention. Removals, immobilization and leaching of phosphorus and sulphur as well as inherent soil heterogeneity on the trial site are additional important considerations in small-plot trials. The only effective means of dealing with these problems is through the testing of soil samples drawn from individual treatments at suitably regular intervals.     

Feedlot management practices and bovine respiratory disease

Bovine respiratory disease is the most commonly recognized problem in feedlot cattle. This article discusses management techniques that can be used to reduce the occurrence of disease and hold it to a manageable level.     

Beef cattle productivity under traditional and improved management in Botswana

Summary A comparison of productivity over a 4-year period from indigenous type beef cattle under two production systems in Botswana is reported. The two systems are: the traditional system on unenclosed communal grazing (cattle post) and ranching within fenced paddocks. Calving percentages, 7-month old calf weight, calf mortality and post-weaning growth to 18 months of age under cattle post conditions were 46·4 per cent, 122·5 kg, 10·2 per cent and 88·5 kg respectively. Corresponding figures for cattle on the fenced ranches were 74·0 per cent, 177·4 kg, 8·5 per cent and 105·8 kg. These results indicate overall productivity estimates of 51 and 120 kg of weaner calf per cow per year and 86 and 188 kg of 18-month old calf per cow per year for the cattle post and fenced ranch respectively.

---

Productividad Del Ganado De Carne Bajo Manejo Tradicional Y Mejorado En Botswana

Resumen Se describe y compara la productividad en un periodo de cuatro años, de ganado de carne indígena bajo dos sistemas de producción en Botswana. Los dos sistemas fueron el tradicional en pastoreo comunal (puestos ganaderos), y el de pastoreo en ranchos con división de potreros. El porcentaje de partos, el peso de los terneros a los siete meses de edad, la mortalidad en animales jovenes y el crecimiento hasta los 18 meses en pastoreo comunal fueron respectivamente 46·4 por ciento, 122·5 kg, 10·2 por ciento y 88·5 kg. Los valores correspondientes para el ganado en ranchos con división de potreros fueron 74·0 por ciento, 177·4 kg, 8·5 por ciento y 105·8 kg. Estos resultados indican estimativos de productividad general de 51 kg y 120 kg en terneros en crecimiento por vaca año y 86 kg y 188 kg en terneros de 18 meses de edad por vaca año para el ganado en pastoreo comunal y en ranchos respectivamente.

---

Productivite De Bovins De Boucherie En Exploitation Traditionelle Et Amelioree Au Botswana

Résumé La productivité de bovins de boucherie de race locale élevés au Botswana suivant deux systèmes différents est comparée pendant une période de quatre ans. L'élevage traditionnel sur pâturage commun non clos et le ranching en enclos sont les deux systèmes utilisés. Les pourcentages de vêlage, le poids des veaux à sept mois, la mortalité des veaux et la croissance du sevrage à 18 mois sont respectivement de 46,4 p. 100, 122,5 kg; 10,2 p. 100 et 88,5 kg pour le bétail sur pâturage non clos et de 74 p. 100, 177, 4 kg, 8,5 p. 100 et 105,8 kg pour le bétail en enclos. Ces résultats entraînent une productivité totale de 51 kg et 120 kg de veau sevré par vache et par an et de 86 kg et 188 kg de taurillon de 18 mois par vache et par an respectivement pour l'élevage traditionnel et celui en enclos.

     

Control of heifer mastitis: antimicrobial treatment-an overview

Initial studies in Louisiana, USA to determine the prevalence of mastitis in breeding age dairy heifers demonstrated that intramammary infections (IMIs) were present in 97% of heifers and 75% of quarters. Most common isolates were Staphylococcus aureus, Staphylococcus hyicus, and Staphylococcus chromogenes; somatic cell counts (SCCs) ranged from 12.4 to 17.3 x 10(6)ml(-1). Histologic examination of Staph. aureus-infected quarters demonstrated significant reductions in alveolar epithelial and luminal areas, and increases in connective tissue and leukocytosis, illustrating limited secretory development and marked inflammation. A one-time infusion of various nonlactating cow antibiotic preparations into infected quarters during different stages of gestation but >45 days prepartum resulted in cure rates for Staph. aureus IMI of 67-100%. Mean SCC was 50% lower at calving for treated heifers, and milk yield over the first 2 months of lactation was 10% greater than that of untreated controls. Subsequent multiple herd studies, however, revealed that use of nonlactating cow therapy was beneficial only in herds exhibiting a high prevalence of heifer mastitis and not in low prevalence herds. Results of lactating cow antibiotic therapy infused 1-2 weeks prepartum demonstrated cure rates of 59-76% vs. 26-31.7% in untreated controls. In some studies, milk production during the first lactation in treated heifers was approximately 10% higher than untreated controls, and SCC were significantly lower; however, in other studies, prepartum treatment was successful in reducing prevalence of infection but had no effect on SCC or milk yield during the subsequent lactation. Thus, treatment of heifers is advantageous because the cure rate is much higher than during lactation, there is no milk loss, and risk of antibiotic residues minimal; however, successful therapy may not necessarily result in lowered SCC and increased milk production in all herds.     

Feeding in relation to suckler cow management and fertility

Profitable suckled calf production, like any other business, depends on the balance between costs and output (Fig 1). The major costs incurred in suckled calf production are feed costs to the cow. Output is simply the weight of weaned calf sold per cow put to the bull, coupled with planned marketing of good quality, cull cows. To maintain this balance at an optimum level requires correct herd management. This can only be achieved with all cows in the herd being at a similar stage of production--a compact two-month calving period. In the long term, a compact two month calving period can only be maintained with correct management of bulling and first-calved heifers. Day-to-day management decisions must be based on the current condition of the cows in relation to the target condition scores set for the system. Understanding this model allows a simple management system to be implemented and achieve the high levels of fertility and suckled calf output required for a profitable enterprise in today's economic climate.     

Alpharma Beef Cattle Nutrition Symposium: implications of nutritional management for beef cow-calf systems

The beef cattle industry relies on the use of high-forage diets to develop replacement females, maintain the cow herd, and sustain stocker operations Forage quantity and quality fluctuate with season and environmental conditions Depending on class and physiological state of the animal, a forage diet may not always meet nutritional requirements, resulting in reduced ADG or BW loss if supplemental nutrients are not provided It is important to understand the consequences of such BW loss and the economics of providing supplementation to the beef production system Periods of limited or insufficient nutrient availability can be followed by periods of compensatory BW gain once dietary conditions improve This may have less impact on breeding animals, provided reproductive efficiency is not compromised, where actual BW is not as important as it is in animals destined for the feedlot A rapidly evolving body of literature is also demonstrating that nutritional status of cows during pregnancy can affect subsequent offspring development and production characteristics later in life The concept of fetal programming is that maternal stimuli during critical periods of fetal development have long-term implications for offspring Depending on timing, magnitude, and duration of nutrient limitation or supplementation, it is possible that early measures in life, such as calf birth BW, may be unaffected, whereas measures later in life, such as weaning BW, carcass characteristics, and reproductive traits, may be influenced This body of research provides compelling evidence of a fetal programming response to maternal nutrition in beef cattle Future competitiveness of the US beef industry will continue to be dependent on the use of high-forage diets to meet the majority of nutrient requirements Consequences of nutrient restriction or supplementation must be considered not only on individual animal performance but also the developing fetus and its subsequent performance throughout life.