Ruminants, Volume 1, Issue 2 (December 2021) – 9 articles

This study evaluated the influence of cow age and temperature adjusted for windchill (T_windchill) on supplement intake behavior of cattle winter grazing rangelands. A mixed-age herd of Angus-based cows (291 and 316 in year 1 and 2, respectively) were classified by age (1-, 2-, 3-, 4-, 5–7-, and ≥8-year-old) and grazed rangeland pasture (329-ha) for two consecutive winters. Cows were provided free-choice access to supplement protein blocks in a SmartFeedPro self-feeder system. An Onset HOBO Weather Station collected data throughout the grazing period. Supplement intake (expressed as kg∙d⁻¹ and g∙kg body weight⁻¹), the coefficient of variation in supplement intake and intake rate (g∙min⁻¹) displayed T_windchill × cow age × year interactions (p ≤ 0.02). In general, cow age displayed a quadratic effect on all supplement intake variables (p ≤ 0.04), where 3- to 4-year-old cattle had the greatest supplement intake with the least variation, while yearling cattle had the least amount of supplement intake and the greatest variation. In conclusion, winter environmental conditions interacted with cow age to affect cattle supplement intake behavior and, consequently, the efficacy of nutrient delivery systems for beef cattle winter grazing on rangelands. Full article

Trichuris spp. are endoparasites found in a wide range of mammalian species. Some of these host species include humans, non-human primates, dogs, cats, pigs, wild ruminants and domesticated ruminants. However, it had been noted that Trichuris are host specific, therefore the parasites that infects wild ruminant species may be transmitted to domesticated animals such as cattle, sheep and goat. Thus, the aim of this review was to identify species of Trichuris that parasitise deer species and to categorise the prevalence of this disease at various geographical locations. It must be noted that the prevalence and intensity of this parasite within deer species was low and rarely showed any signs of clinical disease. However, deer can be a source of infection to domesticated ruminants that may be housed in closed proximity. The review is divided into several sections based on the geographical location of the deer species. In summary, the review shows that most of the identification of various species of Trichuris in deer is based on morphological techniques. However, the use of molecular techniques in the identification of various species of Trichuris is more accurate. In closing, there is a need for more molecular investigations to be done in identifying the species of Trichuris that are present in deer living in the neo-tropical region. Full article

Peripartum dairy cows commonly experience negative energy balance (EB) and immunosuppression together with high incidences of infectious and metabolic disease. This study investigated mechanisms linking EB status with immune defense in early lactation. Data were collected from multiparous Holstein cows from six herds and leukocyte transcriptomes were analyzed using RNA sequencing. Global gene expression was related to circulating IGF-1 (as a biomarker for EB) by subdividing animals into three groups, defined as IGF-1 LOW (<35 ng/mL, n = 35), MODERATE (35–100 ng/mL, n = 92) or HIGH (>100 ng/mL, n = 43) at 14 ± 4 days in milk (DIM). Differentially expressed genes between groups were identified using CLC Genomics Workbench V21, followed by cluster and KEGG pathway analysis, focusing on the comparison between LOW and HIGH IGF-1 cows. LOW cows were older and had significantly lower dry matter intakes and EB values, whereas HIGH cows produced more milk. During the first 35 DIM, 63% of LOW cows had more than one health problem vs. 26% HIGH cows, including more with clinical mastitis and uterine infections. Gene expression analysis indicated that leukocytes in LOW cows switched energy metabolism from oxidative phosphorylation to aerobic glycolysis (PGM, LDH, and PDK4). Many antimicrobial peptides were up-regulated in LOW cows (e.g., PTX3, DMBT1, S100A8, and S100A9) together with genes associated with inflammation, platelet activation and the complement cascade. HIGH cows had greater expression of genes regulating T and B cell function and the cytoskeleton. Overall, results suggested an ongoing cycle of poor EB and higher infection rates in LOW IGF-1 cows which was reflected in altered leukocyte functionality and reduced milk production. Full article

The objective of this study was to evaluate the growth performance responses and liver trace mineral status of newly weaned steer calves offered a low-moisture, molasses-based block “stress tub” containing organic sources of trace minerals and a Saccharomyces cerevisiae fermentation culture during the first 21-d of a 42-d feedlot receiving phase. Newly weaned, single source Charolais x Angus steer calves (n = 46; body weight [BW] = 240; SEM = 1.0 kg) were used in a 42-d randomized complete block design feedlot receiving experiment. On d -1 all steers were individually weighed in the morning for allotment purposes, and steers were then stratified by initial BW and allotted to one of ten pens (n = 4 to 5 steers per pen; 5 pens per treatment) that were randomly assigned to 1 of 2 treatments: 1) no cooked molasses “stress” tub (Con) or 2) ad libitum access to a cooked molasses “stress” tub (Stress Tub; Purina Animal Nutrition, St. Louis, MO, USA) for the first 21-d (Tub). Steers were allotted to their study pens within 36 h of weaning, and the “stress” tub was introduced approximately 24 h post arrival. During the initial 14-d on feed, intake was managed by feed calls to accommodate adaptation to the receiving diet. Following the adaptation period, bunks were managed using a slick bunk management approach. Tub disappearance was monitored daily. Liver biopsies (n = 2 steers/pen) were collected on d 7, 21, and 42 for the determination of Co, Cu, Mn, and Zn. From d 0 to 21 and d 0 to 42, steers from the Tub treatment consumed greater (p ≤ 0.01) amounts of Co, Cu, Mn, and Zn compared with those in the Con treatment. A treatment × day interaction for hepatic concentrations of Co (p = 0.09), Cu (p = 0.01), and Zn (p = 0.01) were noted. On d 7, steers from Tub had greater (p ≤ 0.01) hepatic Co, Cu, and Zn concentrations compared with Con. On d 21, steers from Tub had greater (p ≤ 0.01) hepatic concentrations of Co and Cu; hepatic Zn was similar between treatments (p = 0.83). On study d 42 steers from Tub had greater (p = 0.01) hepatic Cu; however, hepatic concentrations for Co or Zn did not differ (p ≥ 0.34). During the initial 21 d of the experiment, gain efficiency was enhanced (p = 0.03) by 25.0% in steers from Tub compared with Con. Cumulative ADG, DMI, dietary NE utilization and G:F did not differ (p ≥ 0.14) between treatments. It is concluded that the use of stress tubs does not influence the overall growth performance or NE value of the diet during a 42-d receiving period. Stress tub consumption increased hepatic mineral stores during the initial 21-d period and enhanced the Cu status of calves throughout the 42-d period. Full article

To evaluate the influence of linseed and oregano dietary supplementation in Jonica kids, we carried out a trial that involved 30 male Jonica kids 20 days old, divided into three groups of ten animals. Each group was ascribed to one of the following dietary treatments: (C) group control fed without any supplement; (L) group fed control feed containing 3% extruded linseed (Linum usitatissimum); and (L + O) group fed control diet with 0.6% dried oregano (Origanum vulgare) and 3% extruded linseed. The kids were slaughtered at 60 days of age; carcass and cut yields were performed. The Longissimus lumborum muscle was separated to determinate physical, chemical, and fatty acid composition. Supplementation of kids’ diet with oregano did not show effects on performances in vivo and post mortem. Extruded linseed and oregano feed made commercial cuts of kids carcasses less fat (6.75% vs. 10.92% for leg; 4.82% vs. 7.73% for loin), whereas only the extruded linseed diet made the meat fatter (20.11% vs. 19.75%) and more proteic than the commercial pellet (20.11% vs. 19.75%). The use of oregano reduces the meat oxidation compared with the only use of linseed in kids’ diet (0.298 vs. 0.645). The healthy and beneficial effect of linseed in the diet is observed in meat with the lower value of n-6/n-3 ratio (4.57 vs. 8.60) and atherogenic (0.60 vs. 0.77) and thrombogenic (1.36 vs. 1.61) indices. Linseed diet enrich kids meat with healthy fatty acids that are easier to oxidize; instead, the addition of oregano, thanks to its antioxidant properties, allows a longer conservation and a more profitable marketing. Full article

The use of agriculture by-products is highly demanded for livestock nutrition. However, the employment of certain non-degradable materials could potentially induce concretions and lesions in ruminants’ forestomach. Thus, the aim of this study was to determine the morphological lesions showed in rumen containing indigestible foreign objects, named foreign bodies, in small ruminants. Twenty-two animals (12 goats and 10 ewes) presenting foreign bodies (2.750 ± 1.577 kg) were included in this study. Rumenotomies were performed to remove the foreign bodies, and rumen samples were taken for further morphological evaluations. Rumen samples from healthy small ruminants (n = 24) were also taken at slaughterhouses as controls. Morphologically, the rumen from affected animals showed a significant reduction of the ruminal papillae length (1.243 vs. 3.097), hyperplasia of the squamous epithelium, mononuclear infiltration in the subepithelial spaces and, less consistently, vacuolization of keratinocytes, presence of intraepithelial leukocytes and vascular changes of the lamina propria. It can be concluded that indigestible foreign bodies would cause ruminal lesions that would be able to trigger inflammatory and/or degenerative lesions. Our study demonstrates morphological lesions because of the presence of intraruminal foreign bodies, but further studies on the functional activity of the rumen in these cases are required. The avoidance of the presence of indigestible materials in agriculture exploitations is highly recommended in order to prevent the accumulation of indigestible foreign objects in small ruminants. Full article

In a foster cow system, one or more calves are reared by a foster cow. With regard to the growing rejection towards the early separation of cow and calf after calving, such alternative rearing methods with prolonged cow–calf contact are coming more into focus. Nevertheless, there is a lack of recent studies investigating the effects of suckling multiple calves on the udder health of a foster cow. The present study aimed to initially describe the status and development of the udder condition and the microbial colonisation during the foster period. Thereby, the objectives were to determine whether suckling multiple calves was associated with an increase in intramammary infections (IMI) and a deterioration of udder constitution. A total of 99 Holstein Friesian foster cows from a large organic dairy farm in eastern Germany were included in this pilot study. Each foster cow was suckled by 3–4 calves and not additionally milked. Quarter milk samples were taken for cytomicrobiological examination at the beginning and end of the approximately 3.5 months suckling period. At the same time, the udders of 91 of these foster cows were clinically examined by visual assessment and manual palpation. In both the first and second examination (E1 and E2, respectively), Corynebacterium ssp. and non-aureus staphylococci (NaS) constituted the most frequently detected pathogen species in the 385 examined udder quarters. Classifying the quarters into mastitis categories was significantly different between the two examinations (p = 0.001). The number of quarters considered as healthy increased from E1 to E2 by 8.5%. At the same time, the number of quarters with mastitis decreased by 2.6%, the number of quarters with non-specific mastitis by 11.4% and the number of quarters with a latent infection increased by 5.4%. In total, 69.4% of the 121 infected udder quarters in E1 were bacteriologically cured in E2. A cytological cure was achieved in 28.1% of the 385 quarters. Both the bacteriological and cytological cure rate were spontaneous. A new infection occurred in 23.1% of the 385 examined udder quarters and was mainly attributable to infections with Corynebacterium spp. and NaS. During the suckling period, mainly new infections occurred and amounted to 73% in relation to presumed persistent infections (18.9%). The new infections were mainly attributable to infections with Corynebacterium spp. and NaS. Pasteurella spp. were also found in high percentages. A total of 10.1% of the quarters showed an increase in somatic cell count (SCC) above the threshold of 100,000 cells/mL from E1 to E2, indicating a new subclinical mastitis. Regarding udder condition, significant changes during the foster period were an increase in udder skin and teat lesions, a decrease in udder oedema, an increased amount of udder quarters with a consistency considered as normal and an increase in the number of udders showing no sign of udder cleft dermatitis. Moreover, teat length, circumference, and diameter increased significantly (p < 0.05). In conclusion, there is a possibility that suckling multiple calves improves udder health in terms of mastitis but leads to an increased pathogen transmission at the same time, resulting in an increase in latent infections. Additionally, pathogens as Pasteurella spp., which are usually located in the upper respiratory system, could be detected in the mammary gland. The changes concerning the udder condition were manifold. However, it has not yet been conclusively clarified whether all these changes are exclusively due to calf suckling. Further investigations with a non-suckled control group are required. Full article

Ewe deaths affect the productivity and profitability in sheep farming systems and have potential animal welfare and market perception implications. Internationally, there is scant data on the timing and causes of ewe deaths in extensive grazing systems. There is no published literature on the incidence and risk factors associated with casting (ewe in late gestation accidentally immobilised, often in dorsal recumbency). This study, undertaken using a cohort of 1789 ewes on a New Zealand farm, reports on the timing and risk factors associated with production parameters for ewe deaths through an almost two-year period, along with causes of death during both peripartum periods. Ewe deaths occurred throughout both years but were most frequent during the peripartum (pre-lambing to mid-lactation) period. Casting was the most commonly identified cause of death in both years, responsible for approximately a quarter to a third of potential annual mortality. Few risk factors for death or casting were identified. In conclusion, the peripartum period is a high-risk time period for ewe deaths (and, by extension, will also contribute to lamb perinatal mortality). In extensively grazed flocks where casting events occur, it is recommended that all ewes are monitored daily during the peripartum period. Full article

This study investigated potential carry-over effects of increased growth rates prior to breeding at seven months of age on mammary glands of two-year-old ewes bearing one or two lambs, and examined the association between ewe mammary structures and the growth of their progeny. Ewe live weight and mammary ultrasound measures were recorded at 119 days of pregnancy, 29 days of lactation (L29), and weaning of the progeny (L79) in 64 two-year-old ewes selected from two treatments. The heavy group (n = 32) was preferentially fed prior to their first breeding at seven months of age, achieving an average live weight of 47.9 ± 0.38 kg. The control group (n = 32) weighed an average of 44.9 ± 0.49 kg at breeding. Lambs (n = 74) were weighed at birth, L29 and L79. Udder ultrasound measures did not differ (p > 0.10) between treatments, indicating no carry-over effects of treatments on mammary glands of two-year-old ewes. The association between ultrasound measures and lamb growth seemed to differ depending on lamb birth rank. More research is needed to further investigate these associations and determine whether ultrasonography could be used to identify ewes whose progeny would have greater growth rates based on birth rank. Full article