Nutritional Wasting Disorders in Sheep

Mineral and potentially toxic element profiles in the soil-feed-animal continuum: Implications for public, environmental, and livestock health in three pasture-based sheep farming systems

Grazing livestock derive most of their mineral requirements from foraging. The presence of toxic elements in soils has become a significant concern for food safety and ecosystem services. Understanding the mineral content profiles in soil and forage is crucial for assessing animal health, predicting potential transfers of minerals or heavy metals into the food-chain, and assessing threats to the environment and human health. In this study, Na, Mg, P, K, Ca, Mn, Fe, Co, Cu, Zn, Se, As, Cd, Hg, and Pb were measured to determine the mineral status of three different pasture-based farming systems (with grazing sheep livestock) in a Spanish region of significant economic importance. A risk assessment evaluation of animal, environmental, and human health was performed on soil, forage, feed, serum, milk, and wool. Notably, traces of Pb, and As were identified in pastures in all farms. Our calculation of pollution indices revealed moderate levels of contamination by various elements, including Co, Cu, Zn, Se, As, Cd, Hg, and Pb. The two farms with more intense agrosystem practices showed a significant potential ecological risk, characterized by high soil levels of Hg and Cd. Animals from these farms also had high concentrations of these metals in wool. Although the target Hazard Quotient derived from milk consumption suggests that dairy products from this area are safe for consumption for adults, only milk from a dehesa farm (mix of woodland and pastureland) was free of potential health concerns related to Pb exposure. Our assessment of mineral profiles reveals a cohesive relationship between soil quality and derived animal products, particularly of the Merino sheep breeding and farming system. The results reveal the importance of adopting and reinforcing strategies to preserve dehesas as a sustainable and environmentally friendly agrosystem in the western Mediterranean region.

Effects of Carica papaya peel meal-based diets on rabbit bucks' spermiogram and reaction time

The study aimed to evaluate the effects of Carica papaya peel meal-based diet on spermiogram and reaction time in rabbit bucks. Ripe pawpaw fruits were harvested during the dry season. The peels were carefully removed from the pulp and sun-dried for a week. Afterward, they were ground and included in the test diets as pawpaw peel meal (PPM) at inclusion rates of 0%, 15%, and 30%. Rabbit bucks (n = 15) were randomly separated into three groups of five bucks and labeled as groups A, B, and C. Group A, the control group (0%), was fed the basal protein diet (BD), group B (PPM 15) was given a PPM-based diet (15%), while C (PPM 30) was given diet composed of PPM (30%). Semen samples were collected and evaluated fortnightly for 14 weeks. The reaction time and mean ejaculate volume were lower (P < 0.05) in the treatment groups than in the control. Sperm motility and concentration decreased significantly (P < 0.05) across the groups from week 4 to the end of the experiment. Bucks fed PPM 15%, and PPM 30% had significantly (P < 0.05) higher percentages of dead sperm cells and total spermatozoa abnormalities. The control had (86%) normal spermatozoa morphology while those of PPM 15% and PPM 30% were (61%) and (52%), respectively. PPM 30% had the highest abnormal spermatozoa (47%) compared to PPM 15% (38%) and control (13%). The findings indicate that pawpaw peels up to 15% and 30% in the diet have a negative effect on spermiogram.

Depraved appetite in dromedary camels: Clinical, ultrasonographic, and postmortem findings

Background

Camels are subjected to a wide variety of nutritional deficiencies as they are largely dependent upon grazing desert plants. As a consequence, the syndrome of pica or depraved appetite is occasionally seen in dromedary camels. The condition is manifested as chewing or eating abnormal things such as wood, dirt, bones, stones, clothes, plastics, mud, sand, or other inanimate objects.

Aim

This study was designed to investigate the clinical, ultrasonographic, and postmortem findings in dromedary camels with pica or depraved appetite.

Methods

Twenty-five camels of 5 days to 15 years were examined. Owner complaints included depraved appetite, loss of body condition, regurgitation of stomach content, and partial or complete absence of feces. Symptoms described were present for a period varying between 3 days, up to 12 months. The stomach compartments and small and large intestines were scanned using ultrasonography from the right and left sides of the abdomen. Necropsy was carried out on six female and three male camels where the thoracic and abdominal organs were examined with special attention to the digestive system.

Results

The affected animals had a history of gradual loss of body conditions, eating foreign objects, decreased or total absence of feces, and regurgitation of stomach content. Using ultrasound, the foreign body was imaged occluding completely or partially the intestines. Foreign bodies within the rumen could not be visualized with ultrasound. In cases where the rumen is impacted by sand, small pin-points revealing acoustic enhancement were imaged. Foreign bodies were removed from the rumen at exploratory rumenotomy (n = 11), laparotomy (n = 3), or at necropsy (n = 8) in the form of plastics, cloths, sand, mud, wool balls, robes, glasses, or even metallic objects which may be blunt or sharp. Sixteen (64%) of the camels were recovered while the remaining 9 (36%) did not survive.

Conclusion

The syndrome of pica or depraved appetite is an important condition in dromedary resulting in the ingestion of objects other than normal feed. Substantial economic losses are expected as a result of this syndrome. Ultrasonography of the digestive system may help the clinician in some cases to localize of occluding foreign bodies in the intestines, while in the transabdominal scanning of the stomach is valuable only in cases of sand impaction.

Effects of dietary minerals deficiency and supplementation on different parts of muscle minerals content in grazing Mongolian sheep

Objective

The objective of this study was to investigate the impact of dietary deficiency and supplementation of calcium, zinc, copper, cobalt, manganese or selenium on minerals content in the longissimus dorsi (LD), biceps femoris (BF) and triceps brachii (TB) of grazing Mongolian sheep.

Methods

We randomly divided 98 sheep into 7 treatment groups and fed them specific diets for 60 days: a total mineral nutrition diet (LCG), a calcium deficiency diet (LCa), a zinc deficiency diet (LZn), a copper deficiency diet (LCu), a cobalt deficiency diet (LCo), a manganese deficiency diet (LMn) and a selenium deficiency diet (LSe). Then 7 sheep from each group were slaughtered and samples of LD, BF and TB were collected for mineral content analysis. The remaining sheep in each group were subsequently fed specific diets for an additional 41 days: a total mineral nutrition diet (SCG), a calcium supplementation diet (SCa), a zinc supplementation diet (SZn), a copper supplementation diet (SCu), a cobalt supplementation diet (SCo), a manganese supplementation diet (SMn) and a selenium supplementation diet (SSe). Afterward, all sheep were slaughtered, and muscle samples were collected and analyzed.

Results

Significant findings emerged that LCa decreased sulfur (S) content in BF and increased Ca content in LD and BF, while SCa increased S and Ca content in BF and TB, respectively (P < 0.05). LZn decreased Zn, S, and potassium (K) content in LD and BF, while SZn increased Zn and S content in LD and BF, respectively (P < 0.05). LCu decreased Cu and iron (Fe) content in LD and TB, while SCu increased Fe content in TB (P < 0.05). LCo decreased phosphorus, S, K, Ca, Mn, Fe, Cu, and Zn content in LD (P < 0.05). LMn decreased Mn content and increased K content in TB, while SMn decreased K content in BF and TB (P < 0.05). LSe and SSe decreased and increased Se content in LD, BF, and TB, respectively (P < 0.05).

Conclusion

Dietary mineral levels have varying effects on lamb meat minerals content. It is important to ensure an adequate intake of minerals in the diet to enhance the mineral nutrition of lamb meat.

Herd health and reproductive management associated with lamb weight gain and mortality in sub-Saharan drylands-a case from Ethiopia

Sheep are important for food and livelihood security in sub-Saharan Africa, and maximizing lamb weight gain while minimizing mortality is essential to improve production. Using the Menz sheep breeding villages of Amhara region in Ethiopia as a case study, the weight gain and mortality rate of 208 lambs were monitored during their first 5 months of life. The study was conducted in intervention and control villages, where the intervention villages were part of community-based breeding programmes and had participated in various projects aiming to improve sheep production and management. Multivariable linear regression analysis was conducted to detect associations between weight gain from birth to 1 month, and birth to 5 months, and different lamb and ewe characteristics, farmer education, application of management routines, and presence of village level sheep management interventions. In general, lambs from intervention villages, without certain signs of diseases, whose mothers were 2 years or older, had a body condition score of more than 2 on a 5-point scale, and who originated from flocks where disease prevention strategies had been implemented, had gained more weight. Overall lamb mortality was 6.8% with most deaths occurring before 1 month of age. This study highlights that health interventions in ewes improve lamb survival and weight gain and that the care of lambs during the first month of life is crucial for overall herd productivity.

Anaemia in Ruminants Caused by Plant Consumption

Plant toxicology has affected animals throughout evolution. Plants have adapted themselves to the environment. This adaptation has led to the development of defensive strategies to avoid being consumed. Plants have several chemical compounds, which can cause deleterious effects on people or animals that consume them, causing a wide variety of clinical signs. Plants from various latitudes, both cultivated for human and animal feeding or decorative purpose and even wild growth plants are able to generate anaemia in ruminants. Coumarins or ptaquiloside predispose bleeding and haemorrhages, causing a haemorrhagic disease in affected animals. In this group, some important fodder plants, such sweet clover (Genus Melilotus spp.), or other weeds distributed worldwide, such as bracken fern (Pteridium aquilinum) of giant fennel (Ferula communis), are included. On the other hand, sulfur-containing chemicals (e.g., n-propyl disulfate and S-propyl cysteine sulfoxides (SMCOs)) may cause severe direct damage to the erythrocyte and their membrane, leading to their destruction and causing haemolytic anaemia in the animal. This review presents the most frequent intoxication by plants causing anaemia in ruminants. Toxic compounds, clinical signs, diagnosis and possible treatments are also presented.

Gastrointestinal Parasites in Sheep from the Brazilian Pampa Biome: Prevalence and Associated Factors

Parasitic infections are common in sheep farming worldwide. A cross-sectional study was carried out to determine the prevalence and associated risk factors among gastrointestinal parasites and sheep herds from the Brazilian Pampa biome, Rio Grande do Sul state, Brazil. Twenty-one farms were visited, where rectal faecal samples were individually collected from 309 animals. The sheep industry on the studied farms was characterised by small farms with a low level of technification, an extensive grazing system and meat production. Of all samples analysed, strongyle nematodes had the highest prevalence (77.02%), followed by Eimeria spp. (70.55%), Moniezia expansa (20.39%) and Strongyloides papillosus (17.48%). Mixed infection, between helminths and protozoans, was detected in 68.61% of samples. All herds were positive for strongyle and Eimeria spp. A predominance of Haemonchus spp. and Trichostrongylus spp. nematodes was observed in the herds. Younger animals were significantly more affected by Eimeria and M. expansa. In the semi-intensive and intensive systems, a higher frequency of Eimeria and strongyle infections was observed. Parasite infection was significantly reduced at low animal densities. The Brazilian Pampa region presents a high prevalence of gastrointestinal parasites among sheep; age, breeding system and stocking density were factors associated with parasite infection.

Diffuse Alopecia and Thyroid Atrophy in Sheep

Simple Summary

Thyroid dysfunction substantially affects quality of life, causing disturbances in different organs. A low intake of selenium and zinc can predispose to thyroid changes, resulting in hypothyroidism. A deficiency of selenium and zinc causes thyroid dysfunction and skin lesions. This paper describes natural cases of diffuse alopecia and thyroid abnormalities in sheep with selenium and zinc deficiency. The sheep had severe alopecia, and the thyroid hormones serum concentrations were below the reference values for the species. Zinc and Se concentrations were low in the serum and liver, and the thyroid gland was smaller than normal size. The present study is important as it is the first study examining zinc and Se deficiencies causing hypothyroidism in sheep. Furthermore, thyroid disorders affect the quality of life of humans and animals, and are associated with many organ-specific and non-organ-specific disorders.

Abstract

Thyroid dysfunction substantially affects the quality of life due to its association with various disorders in different organs. A low intake of selenium and zinc can predispose to thyroid alterations, resulting in hypothyroidism. A deficiency of selenium and zinc causes direct and indirect skin lesions, both by the action of free radicals on the skin and by thyroid dysfunction. The aim of this study was to describe natural cases of diffuse alopecia and thyroid abnormalities in sheep with selenium and zinc deficiency. Five adult sheep presented marked and diffuse alopecia, and the residual hairs were dry and brittle. The skin was thick and crusty, with marked peeling. The triiodothyronine (T3) and thyroxine (T4) serum concentrations were below reference values for the species. Zinc and Se concentrations were low in both the serum and liver. During necropsy, cachexia associated with serous fat atrophy was observed, and the thyroid glands showed marked atrophy. Microscopically, the thyroid presented multifocal to coalescent atrophy, with atrophied and dilated follicles, macrophage infiltration, and the presence of fibrous connective tissue. The skin revealed hyperkeratosis and edema. It is concluded that thyroid atrophy, alopecia, and hyperkeratosis are associated with low serum and liver concentrations of zinc and selenium in sheep.

Scrapie at Abattoir: Monitoring, Control, and Differential Diagnosis of Wasting Conditions during Meat Inspection

Wasting disease in small ruminants is frequently detected at slaughterhouses. The wasting disorder is manifested by the deterioration of the nutritional and physiological state of the animal indicated by thinness, emaciation, and cachexia. Evidence of emaciation and cachexia, alone, are pathological conditions leading to carcass condemnation during an inspection. Several diseases are associated with a wasting condition, including scrapie, pseudotuberculosis, tuberculosis, paratuberculosis, Maedi Visna, and tumor diseases. On the other hand, parasitic diseases, nutrition disorders, exposure or ingestion of toxins, metabolic conditions, inadequate nutrition due to poor teeth, or poor alimentary diet are conditions contributing to poor body condition. Classical and atypical scrapie is naturally occurring transmissible spongiform encephalopathies in small ruminants. The etiological agent for each one is prions. However, each of these scrapie types is epidemiologically, pathologically, and biochemically different. Though atypical scrapie occurs at low incidence, it is consistently prevalent in the small ruminant population. Hence, it is advisable to include differential diagnosis of this disease, from other possibilities, as a cause of wasting conditions detected during meat inspection at the abattoir. This manuscript is a review of the measures in force at the abattoir for scrapie control, focusing on the differential diagnosis of gross lesions related to wasting conditions detected in small ruminants during meat inspection.

Toxic Wasting Disorders in Sheep

Simple Summary

There are several substances, either inorganic or organic that may be toxic for sheep. Intoxications by some of these substances have an acute clinical course with specific signs and lesions that may guide the diagnostic procedures. However, there are other insidious, subacute to chronic presentations, usually related to continuous intake of the toxic substance over long periods of time, that may present with emaciation, ill-thrift, and/or poor external aspect. In such scenarios, diagnosis may be challenging and should be achieved through a combination of history of exposure, subtle gross and histological findings (if present), and available ancillary tests.

Abstract

Infectious and parasitic agents have been frequently associated with debilitating and wasting conditions in sheep. The prevalence of these agents has probably undermined the role of toxic causes as contributors to such disorders. In addition, many of these intoxications frequently produce acute clinical disease with specific and characteristic lesions, thus a causal relationship with the toxic substance may be relatively easy to establish. However, persistent exposure to some of these organic or inorganic toxic substances may lead to emaciation, ill-thrift, and poor external aspect. The anti-nutritional factors and alkaloids of several plants, including pyrrolizidine alkaloids, among others, have also been associated with emaciation and/or poor general performance in sheep flocks. In this review, some of these disorders are discussed with an emphasis on clinical signs and lesions, relevant diagnostic aspects, and available therapeutic approaches. In most cases, demonstrating a history of exposure should be one of the most relevant aspects of the diagnostic approach, and removing the animals from the toxic source is the cornerstone of the majority of the treatment strategies.