Pasture Conditions Research Articles

PRODUCTION AND QUALITY OF SORGHUM SILAGE INTERCROPPED WITH MARANDU GRASS AND PIGEONPEA

Lack of forage in the winter dry season is a concern for cattle production in tropical Brazil. Pasture renovation with silage production might solve an immediate concern for forage production and help develop an improved pasture condition after cropping. The present study was focused to compare the production and quality of monocropped sorghum and sorghum intercropped with Marandu grass and/or pigeonpea in two row spacings. The experiment was carried out on a sandy Oxisol in São Paulo state in Brazil with an experimental design of a 2 x 4 factorial arrangement with four replications. Treatments were: monocropped sorghum, sorghum intercropped with Urochloa brizantha, sorghum intercropped with Cajanus cajan (cv. BRS Mandarim), and sorghum intercropped with Urochloa+ pigeonpea with 0.45 and 0.90 m row spacings. Greatest forage production was with 0.45-m spacing for monocropped sorghum and dual-species intercropping. With 0.90-m spacing, greatest production was for Sorghum+Urochloa. Sorghum+Urochloa+Cajanus intercropping provided the highest concentrations of crude protein in silage, regardless of row spacing. An increase in ensiling time reduced quality of the silage due to a decline in crude protein and TDN and an increase in fibers. However, the reduced spacing between lines with the inclusion of legumes resulted in a greater amount of silage with a higher concentration of protein.

Variation in Dung Removal Rates by Dung Beetles (Coleoptera: Scarabaeoidea) in a Temperate, Dry Steppe Ecosystem

During their feeding process, dung beetles perform a series of ecosystem functions that provide valuable ecosystem services, such as soil fertilization, improvement of soil properties, plant growth enhancement, and biological pest control. However, in the grasslands of the Central Asian dry steppe, the effects of dung beetles on dung removal remain almost unstudied. Here, we examined dung removal by different dung beetle species (Colobterus erraticus (Linnaeus, 1758), Onthophagus bivertex Heyden, 1887, Onthophagus gibbulus (Pallas, 1781), Gymnopleurus mopsus (Pallas, 1781), Cheironitis eumenes Motschulsky, 1859, and Geotrupes koltzei Reitter, 1892), and compared the impacts with control treatments (without beetles) under natural pasture conditions and in the laboratory. We examined the influence of different variables on dung removal rates, such as dung type and dung beetle traits (nesting strategies, abundance, body size, and biomass). We found higher dung removal rates during the initial 48 h in field and laboratory conditions. Among nesting strategies, tunnellers demonstrated significantly higher dung removal rates than dweller and roller species. The highest amount of dung removal was estimated for C. eumenes (6.5 g/day by seven individuals). We found no significant relationship between dung removal rates and dung beetle body size or biomass, but we observed a strong negative correlation between dung beetle abundance and dung removal rates. Our findings highlight the importance of dung type and age, nesting strategies and abundances of dung beetles, and experimental conditions, which are the main factors driving the process of dung removal.

Whole transcriptome sequencing reveals core genes related to spermatogenesis in Bactrian camels.

Bactrian camels survive and reproduce better in extreme climatic conditions than other domestic animals can. However, the reproductive efficiency of camels under their natural pastoral conditions is low. Several factors affect mammalian reproductive performance, including testicular development, semen quality, libido, and mating ability. Testis is a main reproductive organ of the male and is responsible for producing spermatozoa and hormones. However, our understanding of the expression patterns of the genes in camel testis is minimal. Thus, we performed total RNA-sequencing to investigate the gene expression pattern. As a result, 1,538 differential expressed mRNAs (DEmRNAs), 702 differential expressed long non-coding RNAs (DElncRNAs), and 61 differential expressed microRNAs (DEmiRNAs) were identified between pubertal and adult Bactrian camel testes. Then the genomic features, length distribution, and other characteristics of the lncRNAs and mRNAs in the Bactrian camel testis were investigated. Target genes of the DEmiRNAs and DEmRNAs were further subjected to gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Genes, such as AMHR2, FGF1, ACTL7A, GATA4, WNT4, ID2, LAMA1, IGF1, INHBB, and TLR2, were mainly involved in the TGF-β, PI3K-AKT, Wnt, GnRH, and Hippo signaling pathways which relate to spermatogenesis. Some of the DEmiRNAs were predicted to be associated with numerous DElncRNAs and DEmRNAs through competing endogenous RNA (ceRNA) regulatory network. At last, the candidate genes were validated by RT-qPCR, dual fluorescent reporter gene, and a fluorescence in situ hybridization (FISH) assay. This research provides high-throughput RNA sequencing data of the testes of Bactrian camels across different developmental stages. It lays the foundation for further investigations on lncRNAs, miRNAs, and mRNAs that involved in Bactrian camel spermatogenesis.

Increasing the milk productivity of Kazakh jabe horses.

The purpose of the study was to determine the milk productivity and chemical composition of the milk of mares of the Kazakh breed of the jabe type (KJ) and the Novoaltay-Kazakh crossbreeds of the 1st generation (NA x KJ) in the conditions of herd keeping. To determine the milk productivity of mares, 2 experimental groups were formed with a total of 30 mares, 15 individuals were selected in each group. The studied animals were formed according to the principle of pairs of analogues in the context of full-age groups from 5 to 11 years. Kazakh horses of the jabe type in the group of experimental mares in milk have an average live weight of 433.5 kg, and are significantly inferior to the Novoaltay-Kazakh crosses (515.3 kg). The body measurements were 142.0-149.0-174.9-18.2 cm in Kazakh horses of the jabe type, and 150.1-157.1-186.7-20.02 cm, respectively, in Novoaltay-Kazakh crossbreeds. According to the results of studies, the milkiness of mares of the Novoaltay-Kazakh crosses for 105 days of lactation averaged 1932 liters or higher by 25.2% (487.2 liters) than the milkiness of mares of the Kazakh breed of the jabe type. As a result of studies on the composition of milk of mares of different genotypes, it was found that in mares of Kazakh jabe, on average, protein and fat indicators compared to Novoaltay-Kazakh crossbreeds were higher by 0.07% and 0.05%. In the course of determining the live weight of mares among the experimental groups, it was found that the Novoaltay-Kazakh crossbreeds, on average, had a higher live weight of 515.3 kg or higher compared to the Kazakh jabe by 81.8 kg (15.8%). Thus, the studies have proved the prospects of using stallions of the Novoaltay breed to increase the milkiness of local Kazakh horses of the jabe type in herd and pasture conditions.

Improving condition of desert pastures by planting saxaul and cherkez plants

The article provides information on large degraded areas in almost all areas, of which 17.5 million hectares of dry natural pastures are allocated for cattle breeding out of 32 million hectares of desert and semi-desert areas in Uzbekistan. It is also noted that 40% of desert and semi-desert pastures have degraded pastures to varying degrees, the average productivity has decreased by 20-30%, and 8.0 million degraded pastures should be improved first. To improve the condition of degraded desert and semi-desert pastures, the authors noted that it is possible to increase their productivity by 10-15 times due to the establishment of cultural pastures by replanting nutritious wild plants and comparing their productivity. To improve the productivity and ecological restoration of degraded livestock pastures in our Republic's desert and semi-desert areas, he considered the mechanization of planting saxovul and cherkez plants from nutritious shrubs and developing a planting unit for this purpose. For this purpose, the devices used in planting the seeds of plants with the same physical and mechanical properties as the desert plants from the seeds of nutritious plants growing naturally in the wild in our Republic and foreign countries and their shortcomings have been determined.

Isparta İlinde Yetiştirici Koşullarındaki Kıl Keçilerinin Morfolojik Özellikleri

In this study, the morphological body characteristics of hair goats bred in Isparta province, such as withers height, back height, rump height, chest width and body length, were investigated. The animal material of the study consisted of 45 hair goats in 3 farms in total, in lowland conditions, high pasture and highland conditions in the center of Isparta. In the examinations, it was found that the measurements of the males were longer than the measurements of the females in terms of withers, back and rump height, chest circumference and body length, respectively. While the difference was found to be significant in terms of withers height, back height, rump height, and body length (p

Virtual Fencing Technology for Cattle Management in the Pasture Feeding System—A Review

Maximizing annual pasture consumption without negatively impacting individual cow performance is of great importance in grass-based dairy and beef systems due to pasture being the most cost-effective nutrient source. However, the disadvantages of conventional and electric fencing include material and labor costs and increased manual labor. Virtual fencing has been developed and evaluated for almost two decades. The evolution of precision livestock farming, specifically virtual fencing, presents new opportunities for maximizing the utilization of available pasture land. Virtual fencing technology decreases the labor involved in physical fencing, provides greater adaptability to changes in pasture conditions, increases precision and efficiency, and offers additional flexibility in grazing management practices. However, that innovative technology should be further developed, and improvements should include decreasing the total costs of the system and increasing its application to other technological groups of ruminants, e.g., suckler cows with calves, increasing the efficiency of the system operation in large areas and a larger number of animals. Recent advancements in electronic communication and device (i.e., collar) design hold the potential to significantly enhance the effectiveness of the technology while also reducing costs. However, it is necessary to conduct a further evaluation to determine their utility in precision agricultural systems. This review paper aims to present an innovative concept of virtual fencing technology for pastures, compare currently available systems of this type, and indicate areas where further research and development should be carried out using Internet of Things (IoT) systems.

Activity behavior of goitered gazelles in an arid environment

The daily activity pattern in ruminants consists mainly of alternating foraging with bouts of resting, while other behaviors usually play a minor role in the daily activity budgets of ungulates most of the year. Interactions of both intrinsic and extrinsic factors force animals to adopt compromises to form optimal time proportions for foraging and resting to satisfy their daily energy demands. This paper considers the impact of ambient temperature, pasture conditions, body-size, and the effects of lactation and animal growth on the daily activities of goitered gazelles (Gazella subgutturosa). My study found: 1) temperature was the most significant factor leading to the greatest daily hour-to-hour variations in activity, as well as significant monthly changes in activity fluctuations; 2) seasonal improvement of forage conditions did not have a distinctive effect on daily activity; 3) the effect of body size, lactation and fawn growth also did not noticeably change activity fluctuations; but 4) factors related to hiding behavior had a significant impact on goitered gazelle activity. Though goitered gazelles are a sexually dimorphic species, they did not demonstrate any significant deviation between males and females in their daily activities in contrast to typical dimorphic ruminants. The goitered gazelles’ hiding behavior may provide a possible explanation for this distinction, as other previously observed dimorphic ungulates were mainly species where fawns followed their mothers from birth. Among other influences, ambient temperature and features of their hiding behavior were the most significant factors influencing diurnal activity of goitered gazelles, while age and sex had a weaker impact on daily behaviors.

PSI-20 Effect of Different Forage Allowances During the Middle and Final Thirds of Pregnancy in Nellore Dams Pregnant with Female Calves on Offspring Performance and Milk Yield

Abstract This study was conducted to evaluate the impact of maternal nutrition, during the middle and final thirds of pregnancy of Nellore dams pregnant with female calves, on the milk yield of the dams and on the performance of the offspring from calving to weaning. The experiment lasted 390 days, divided into two phases: gestational phase (150 days - from June to November 2019) and nursing phase (240 days - from November/2019 to July/2020). Forty-two multiparous Nellore dams pregnant with female calves were used [initial BW of 425 ± 36 kg and body condition score (BCS) of 3.67 ± 0.23] in a randomized block design (blocked by BW), with the experimental unit being the paddock and six replicates per treatment. The treatments consisted in two forage allowances (FA) during pregnancy: low forage allowance (LFA; 2.80 kg DM/kg BW) and high forage allowance (HFA; 7.60 kg DM/kg BW). The dams were kept in an area composed of Urochloa brizantha cv. Marandu and received a protein supplement (1 g/kg BW/day). In the suckling phase, all animals remained under the same conditions of pasture and supplementation (ad libitum mineral salt) until weaning. Data were analyzed using SAS PROC MIXED. Corrected milk yield (4% fat) and total milk fat and solids content were affected by the FA (P< 0.04), with the least values observed in the milk of animals subjected to LFA. female calves from dams subjected to LFA during pregnancy were 11 kg lighter (P=0.02) and showed adecreased average weight gain (-0.08 kg/day) at 120 days from calving (P=0.03), and also showed less rib-eye area (-3.10 cm²) at weaning (P =0.03). Dams subjected to LFA during pregnancy possibly went through nutritional restriction, which caused changes in milk yield and milk composition during nursing phase, implicating lower performance of the offspring until weaning.

PSVIII-4 Impact of Different Forage Allowances During the Middle and Late Thirds of Pregnancy of Nellore Dams Pregnant with Female Calves on dam Performance

Abstract The study aimed to evaluate the impact of forage allowance (FA) on performance, during pregnancy until weaning, of dams pregnant with Nellore female calves subjected to two different FA during the middle and final thirds of pregnancy. The experiment lasted 390 days, divided into two phases: gestational phase (150 days - from June to November 2019) and nursering phase (240 days - from November/2019 to July/2020). Multiparous Nellore n = 42; initial BW of 425 ± 36 kg and body condition score (BCS) of 3.67 ± 0.23] dams pregnant with female calves were used in a randomized block design (blocked by BW), with the experimental unit being the paddock and six replicates per treatment. The treatments consisted of two different FAs during pregnancy phase: low forage allowance (LFA; 2.80 kg of DM/kg of BW) and high forage allowance (HFA; 7.60 kg DM/kg BW). The dams were kept in an area composed of Urochloa brizantha cv. Marandu and received a protein supplement (1 g/kg BW/day). In the nursing phase, all animals remained in the same pasture conditions and supplementation (ad libitum mineral salt) until calves were weaned. The data were analyzed using the SAS PROC MIXED. Dams subjected to LFA had reduced BW (-35 kg) and BCS (-0.23) at calving (P< 0.01). All variables measured in the carcass, except marbling score (P=0.33), showed differences (P< 0.01) between treatments at calving, with the least values observed in the animals subjected to LFA. At weaning, dams subjected to LFA had reduced BW (-16 kg; P< 0.01). Dams subjected to LFA, at the level and period evaluated, probably went through feed restriction during the middle and final thirds of gestation, implicating lower performance and deposition of tissues in the pre and post calving until weaning.

74. Monitoring suckling behaviour of beef calves under pastoral conditions: A review

74. Monitoring suckling behaviour of beef calves under pastoral conditions: A review

Intake, performance, and feeding behavior of Holstein and Holstein × Gyr heifers grazing intensively managed tropical grasses during the rainy season

Holstein × Gyr and Holstein are the primary dairy breeds used in tropical systems, but when rearing under pasture, feed intake, behavior, and performance might differ between them. This study aimed to evaluate the voluntary intake, nutrient digestibility, performance, and ingestive behavior of Holstein and Holstein × Gyr (½ Holstein × ½ Gyr) heifers managed in a rotational system of Guinea grass (Panicum maximum Jacq. cv. Mombaça). The experiment was conducted during the summer season throughout four periods of 21 d. Two 8-heifers (four Holstein and four Holstein × Gyr) groups, averaging 258.6 ± 24.79 kg and 157.1 ± 24.99 kg BW, were used. Each group grazed a separate set of 16 paddocks, and all heifers received a concentrate supplement daily. Heifers were weighed at the beginning and end of the experiment. Fecal, forage and concentrate samples were evaluated for their DM, CP, crude fat, ash, NDF, and indigestible NDF. Feeding behavior was evaluated through 24 h of live observation for 48 h of each experimental period. Grazing, ruminating, resting, and intake of concentrate times were recorded, and rumination criteria, bout criteria, mealtime, meal frequency, and meal duration were calculated. There was no difference in total dry matter intake (DMI), but forage DMI of Holstein × Gyr was 11.70 % greater than the Holstein heifers. The Holstein × Gyr heifers had greater NDF intake and feed efficiency tended to show greater CP and NDF digestibilities, consequently, they had greater average daily gain (ADG). Holstein grazed less than Holstein × Gyr heifers in the afternoon. Ruminating time was 18.43 % lower for Holstein than Holstein × Gyr heifers, and rumination criteria (i.e. longest non-feeding interval within a rumination event) were greater for Holstein heifers. Holstein heifers presented more prolonged rumination bouts and resting time than Holstein × Gyr heifers. Holstein × Gyr can ingest and ruminate greater amounts of fibrous material, and Holstein heifers needed to spend more time ruminating the cud. Overall, even though the behavior was not markedly different between breeds, rearing young Holstein heifers in tropical pasture conditions is less suitable than Holstein-Gyr because of their lower ADG. Therefore, this management condition seems appropriate for Holstein × Gyr but inappropriate for Holstein dairy heifers.

Effective methods of preventing degradation of desert pasture soils of Uzbekistan

Natural desert pastures are the main source of fodder for the livestock of the republic, which allows them to use desert pastures all year round. In this research, effective agro-technical measures used to cultivate promising varieties of desert forage plants suitable for soil-climatic conditions was studied in order to improve the condition and increase the productivity of degraded desert pastures. Predictive methods were employed to development of agro-technical measures aimed at restoring, maintaining, increasing and protecting the fertility of sandy desert soils in improving the condition of desert pastures, and to implement a number of complex measures, such as overcoming the process of soil degradation. According to the results, The results showed that seeds of shrubs and semi-shrubs are sown at a depth of 1.5-2.0 cm, the norm of sowing the seeds of the same crop, salsola orientalis and haloxylon 6-8 kg/ha, male grass 5-6 kg/ha and other desert plants planted in accordance with regulatory documents. Once the seedlings began to germinate, field germination of seeds, number of seedlings and retention dynamics, development of adult plants, and formation of the root system were determined.

Effectiveness of application of mineral fertilizers in growing food plants in desert pasture conditions of Uzbekistan

Pastures are the main source of fodder for the desert livestock of the country and can be used all year round. Pasture fodder is the cheapest source of fodder. This research work focused on the effectiveness of the use of mineral fertilizers in the cultivation of forage crops in desert pastures, phenological observations of desert forage plants, the determination of the amount of macronutrients in the vegetative organs of desert forage plants. Based on the results, one of the most effective ways to get high yields from desert forage plants was the use of mineral, local, micro and bacterial fertilizers. Moreover, it was found that preventing the degradation of sandy desert soils and improving fodder production for livestock depended on the planting and care of high-yielding desert forage crops, mainly in desert pastures. In general, the use of agro-technical measures was aimed at preventing the degradation of sandy desert soils and improving natural pastures, ensuring the germination of seeds of various desert forage plants in sandy desert soils, achieving growth and accumulation of high nutrient mass, and using mineral forage plants.

Plant molluscicide based on Smolevka white (Silene Latifolia) as prevention of pastoral helminthiasis of animals

Soft-bodied is the intermediate host of helminthiases, in the body of which several development stages of larval forms of helminths occur. There is the highest population density of mollusks in the areas of ruminant grazing, which leads to mass infection of animals with trematodes. To destroy the intermediate host of helminths in agricultural production, molluscicidal remedies of synthetic and plant origin are used. The work aimed to determine the molluscicidal effectiveness of a plant remedy based on Silene Latifolia in conditions of natural pastures. The material for work was the green mass of the plant S. Latifolia obtained in the warm season from roots, leaves, stems, flowers, and seeds. By grinding this plant, a powder with a particle size of 1-3 mm was obtained. Then, the powder was extracted with ethyl alcohol. The obtained product (concentrate) was an amorphous gel-like mass of dark green color with a specific smell and well soluble in water. Fieldwork in natural pastures was carried out on 5 biotopes with an area of 4-25 m2. Three species of gastropods were recorded from freshwater mollusks in the biotopes: Planorbis planorbis, Planorbarius corneus, Physa fontinalis, Lymnaea truncatula, and L. palustris. The results of experiments conducted in the conditions of pastures indicate a high molluscicidal activity of the studied plant agent on pond fish, intermediate hosts of trematodes pathogens. The effectiveness of the developed molluscicide on gastropods, when treated with a working solution (10.0 g/l) is from 98.1 to 100%.

The transfer of passive immunity in calves born at pasture

Calf and dam separation is an area of growing public interest, and timely separation is also a practical challenge for pastoral farmers to achieve for all calves. Very few studies have investigated the success of leaving calves with their dams in pastoral conditions, so this observational study assessed serum total protein (STP) in calves born at pasture and left to suckle from their dams for up to 24 h. It also investigated failure of transfer of passive immunity (FPT) once calves had been provided colostrum from the farmer and some factors that may contribute to the risk of FPT. Over 2 years, 8 farms (4 in the North Island, 4 in South Island of New Zealand) were involved in an observational study where cows and calves were observed for 24 h a day for 2 wk per farm. Observers recorded the time from birth to first suckling, number of suckling events, time of calf removal from the dam, and ambient temperature. Calves were blood sampled on arrival at housing, before receiving colostrum from the farmer (d 1), and again 2 d later (d 3) to test for STP concentration. On d 1, 689 calves had blood samples collected, at a median of 11.5 (interquartile range 5.6 to 19.2) hours postbirth. Of these, 283 calves [41.1%; 95% confidence interval (CI) 37.4 to 44.9%] had STP >52 g/L (proportion by farm ranged from 10 to 78%). On d 3, 680 blood samples were collected, of which 16.0% (95% CI 13.5 to 19.0) had FPT (STP ≤52 g/L) with proportion by farm ranging from 2.5 to 31.6%. The FPT risk at d 3 in calves that did not suckle before housing was 2.91 (95% CI 2.04 to 4.13) times the risk in calves that suckled. For every hour longer postbirth that it took for a calf to have its first suckling event, odds of FPT at d 3 increased by 1.21 (95% CI 1.08 to 1.36) times, and compared with calves that only suckled once, calves that suckled 2, 3-5, or >5 times had 0.42 (95% CI 0.15 to 0.99), 0.35 (95% CI 0.15 to 0.76), and 0.10 (95% CI 0.005 to 0.47) times the odds of FPT, respectively. For every 1-percentage-point increase in the Brix % of the colostrum, the odds of FPT decreased by 33% (95% CI 24- to 42). Calves that suckled in the paddock and were fed colostrum with ≥22% Brix had the highest STP, and lowest odds of FPT, of any suckling/Brix % combination. There was a trend for STP to be greater in calves that suckled in the paddock and fed <22% Brix compared with calves that did not suckle in the paddock and fed ≥22% Brix. However, the calves in the former group also tended to have a greater risk of FPT at d 3, and a greater STP variability. There were very large between-farm variabilities for rates of suckling, colostrum feeding, and FPT risk that urgently require further investigation for calves born at pasture.

The state of the horse breeding industry and the evaluation of horses at the state enterprise dibrivka stud farm 62

Preservation of genetic resources of the horse breeding industry at the State Enterprise Dibrivka Stud Farm is currently relevant, as there is a reduction in the number of valuable breeds of horses and the destruction of their gene pool in Ukraine. The purpose of the work was to research the state of the horse breeding industry and to conduct a quality assessment of horses at State Enterprise Dibrivka Stud Farm 62, Dibrivka village, Myrhorod district, Poltava region, in order to establish effective operation of the enterprise. State Enterprise Dibrivka Stud Farm 62 breeds the Orlov Trotter, Russian Trotter and Novoolexandrian Draught breeds. It was observed that stallions and mares (their height at the withers, length of the body, chest circumference, cannon bone circumference) of the Orlov Trotter breed, Russian Trotter breed and Novoolexandrian Draught breed correspond to the elite class and mostly predominates it in breeding value and economic purpose of stallions and breeding mares at the horse farm. At State Enterprise Dibrivka Stud Farm 62 the population of stallions and mares received a high rating by the main points (origin, type, exterior, and measurements); it was 5.5–9. It indicates a high genetic potential of the herd and a purposeful breeding work with it. It is necessary to improve the feeding of horses (increase the supply of good quality hay, concentrated feed, diversify the diet of breeding stallions, improve the condition of pastures) in order to use the genetic potential of animals effectively.

Estimation of forage quality by near infrared reflectance spectroscopy in dallisgrass, Paspalum dilatatum, poir

Dallisgrass ( Paspalum dilatatum Poir.) is an economically important and widely cultivated forage crop for livestock feeding in the tropical, subtropical, and warm temperate regions because of good adaptation to unsuitable pasture conditions. In this study, 216 dallisgrass samples were used to develop near infrared reflectance calibrations to estimate five forage quality parameters: dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and ash. Second derivative pretreatment was applied for calibration of DM, CP and NDF while a first derivative pretreatment was used for ADF and ash. The coefficients of determination in the internal validation set (r 2) were 0.78 for DM, 0.80 for CP, 0.95 for NDF 0.75 for ADF, and 0.71 for ash. The relative predictive determinant ratios for calibration indicate that the NDF equations were acceptable for quantitative prediction of dallisgrass quality, whereas the DM, CP, ADF, and ash equations were useful for screening purposes. The near infrared prediction models developed in this study can be used for screening in the forage breeding researches to be carried out for five quality parameters in the future.

7 Awardee Talk: Muddy Environmental Conditions Increase Net Energy Requirements and Decrease Cow and Heifer Body Weight and Body Condition During Late Gestation

Abstract Winter and spring precipitation are expected to increase 20-30% by the end of the century in the Midwest, U.S. As a result, cows in this region are exposed to muddy conditions in pastures during late gestation. Two experiments were completed with multiparous cows and primiparous heifers to determine the energetic cost of mud during late gestation. In the first experiment, multiparous Angus cows (n = 8/treatment) were paired based on initial body weight (BW). One cow from each pair was randomly assigned to either the mud (MUD) or control (CON) treatment. Cows were housed and fed individually from d 213 to 269 of gestation. Each pair was fed to meet requirements for maintenance and gestation. In the second experiment, primiparous Angus heifers (n = 9/treatment) were paired based on initial BW. One heifer from each pair was randomly assigned to either the MUD or CON treatment. Heifers were housed and fed individually from d 196 to 266 of gestation. Each pair was fed to meet requirements for maintenance, growth, and gestation. Data in both experiments were analyzed as randomized complete block designs with repeated measurements (SAS 9.4). Although cows consumed the same amount of dry matter, cows in the MUD treatment weighed 37.4 kg less than the CON treatment (P &amp;lt; 0.01) and were 1.5 body condition score (BCS) units less (P &amp;lt; 0.01) by d 269 of gestation. Similarly, heifers in the MUD treatment weighed 43.5 kg less than the CON treatment (P &amp;lt; 0.01) and were 1.8 BCS units less (P &amp;lt; 0.01) by d 266 of gestation. In both experiments, however, calf birth weight was similar (P = 0.34). Although cows and heifers housed in mud were in a negative energy balance, they prioritized fetal growth and mobilized body tissues to meet the energetic demands of gestation.

Retention of internal teat sealants over the dry period and their efficacy in reducing clinical and subclinical mastitis at calving

Internal teat sealants (ITS) reduce the risk of new intramammary infections over the dry period by forming a physical barrier to pathogen ingress. As the first and last 2 wk of the dry period are high-risk periods for new infections, maintaining an effective barrier in this period is a key requirement. Few studies have systematically examined sealant retention and none have done so under New Zealand pastoral conditions, where cows frequently move to separate grazing for dry periods, typically 80 to 90 d long. This multi-herd study was a split-udder equivalence trial comparing 2 ITS formulations for retention and efficacy in preventing periparturient clinical and subclinical mastitis. Both ITS contained 65% (2.6 g) bismuth salts, which contribute to the barrier within the teat canal, emulsified in ≤1.4 g of mineral oil. However, one ITS additionally contained <10% amorphous silica. At dry-off, treatment was randomly allocated to diagonal teat-pairs within 409 cows on 4 farms. All cows met industry best practice criteria for ITS treatment alone. The study unit was quarter within cow and farm. Outcomes included clinical mastitis (CM) incidence for the last 7 d of the dry period and first 42 d of lactation, subclinical mastitis (SCM) incidence 96 h after calving, and quantity of residual after centrifuging 50 mL of colostrum collected from each quarter within 24 h of calving. Proportional outcomes were analyzed using Bayesian mixed models with a binomial distribution and logit link function, whereas the quantity of residual was analyzed using Bayesian finite mixture models and cluster bootstrapping. We set a region of probable equivalence (ROPE) of ±2.5% between proportions and ±0.2 g for residual weight. Records were available for 1,596 quarters (399 cows). We detected no meaningful difference in incidence of CM or SCM attributable to differences in sealant: the model predicted treatment differences of 0.00 with a 95% highest density interval (HDI) of ±1.00%. Across all cows and farms, the marginal difference in the percentage of quarters with CM was 0.11% (95% HDI: -2.11 to 2.49%), and for SCM 0.00 (95% HDI: -1.98 to 1.94%). Including the quantity of residual recovered at calving did not improve fit or predictive ability of the models predicting CM or SCM, and the coefficient spanned the null value. The distribution of the weight of material recovered at calving was multi-modal; for 25% of quarters, more residual was recovered than inserted. When the residual weight was less than or equal to the median residual weight (2.06 g; range: 0.19-6.03 g), there was a ≥90% probability that any treatment difference in residual was ≤0.2 g. When the residual weight was between the median and 75th percentile (4.40 g; 95% HDI: 4.00 to 4.75 g), there was no clear difference in residual between products. Above the 75th percentile, there was a 90% probability that the residual from quarters differed by product type (difference = 0.36 g, 90% HDI: 0.20 to 0.54 g). In conclusion, both products had equivalent efficacy for SCM and CM. As the quantity of residual increased, the difference in residual weight recovered increased but this may represent increases in debris rather than indicating a more effective barrier.