Lamb Deaths Research Articles

Feeding twin-bearing Merino ewes above the metabolisable energy requirements for maintenance during late gestation increases the duration of parturition of the first-born lamb

Context In Australia, approximately 53% of lamb deaths are caused by dystocia. One of the main welfare concerns in the sheep industry is under- and overfeeding ewes, which may be contributing to cases of dystocia. Aims This pilot study aimed to investigate how increasing energy intake affects the duration of parturition and predictors of lamb survival. Methods On Day 100 of gestation (dG), 20 twin-bearing and 10 singleton Merino ewes were selected and allocated to three treatment groups; (1) singleton ewes fed at 1.0× maintenance levels (n = 10); (2) twin-bearing ewes fed at 1.0× maintenance levels (n = 10) or (3) twin-bearing ewes fed at 1.25× maintenance (n = 10). Ewes were housed indoors in individual pens. Urine and blood were sampled from ewes on dG 130, 140, then daily from dG 145 through to parturition, and blood was sampled at the onset of parturition and 30 min post-partum. Urine was analysed for pH and blood was analysed for metabolic parameters, mineral concentration and acid–base balance. Predictors of lamb survival from birth to 24 h consisted of weight, rectal temperature, blood glucose and lactate, and body morphology. Key results Serum calcium in late gestation and blood base excess pre-parturition were higher in Singletons 1M compared with Twins 1M (P < 0.05). The Twins 1.25M group took longer to give birth to the first-born lamb (104.4 ± 21.1 min) compared with the Twins 1M group (44.1 ± 6.6 min; P = 0.015). There were no differences in the predictors of lamb survival measures between the twin-bearing groups (P > 0.05). Conclusions Ewes from the Twins 1.25M group took significantly longer to give birth to the first-born lamb. There were no other significant findings between the twin-bearing groups, including lamb liveweight, however, lambs born to ewes from the Twins 1.25 group were numerically heavier, which may explain the increase in parturition length. Implications Feeding ewes above maintenance did not provide any production benefits to metabolic health or any other physiological parameters. Producers should avoid overfeeding ewes during late gestation.

Mycoplasma ovis infection causing anaemia and death in Scottish lambs.

Mycoplasma ovis infection causing anaemia and death in Scottish lambs.

Tickborne disease contributing to lamb deaths across Scotland.

Tickborne disease contributing to lamb deaths across Scotland.

Mannheimia haemolytica-associated fibrinonecrotizing abomasitis in lambs.

Mannheimia haemolytica-associated abomasitis has been clinically described as a cause of sudden death in lambs, but it is poorly characterized. We describe the pathological features of a severe fibrinonecrotizing abomasitis in 3 lambs that died suddenly. All 3 abomasums had a thickened submucosa due to edema and necrotic areas delimited by bands of degenerate neutrophils with slender nuclei (oat cells) and angiocentric distributions. The overlying mucosa was congested. Myriads of gram-negative coccobacilli were observed within the oat cell bands. M. haemolytica was isolated from the abomasum in all 3 animals and was serotyped as A2 in one of them. Pericarditis and pleuritis were observed in 2 of the lambs. Clostridium spp. were isolated in 1 lamb and detected by immunohistochemistry in the 3 animals, suggesting clostridial co-infection. M. haemolytica should be considered among the differential diagnoses of necrotizing abomasitis in lambs.

Causes of Lamb Mortality in the Lacaune Sheep Breed in Iran

Background: Neonatal mortality is a significant multifactorial problem that affects flock productivity. Different infectious and non-infectious factors have been attributed to lamb losses. The objective of the present study was to identify the major causes of neonatal mortality.
 Methods: In a 3-months period, 114 Lacaune breed lambs died of which 52 animals were lost with clinical signs of infection. Heart and lung samples were collected and transmitted to the laboratory. Microbiological cultures following biochemical tests were conducted to identify bacterial infection of the lambs.
 Results: A total of 52 out of 114 lambs (45.6%) were infected with bacteria. The bacteria including Escherichia coli (30.8%), Proteus mirabilis (19.2%), Pasteurella multocida (1.5%), Corynebacterium pseudotuberculosis (7.7%), Mannheimia haemolytica (3.9%), Staphylococcus epidermidis (1.9%) were isolated. The role of the identified pathogens was more significant in lamb death compared to noninfection causes. Diarrhea was the most euoitcefni disease followed by septicemia and pneumonia. Escherichia coli was isolated significantly more than other bacterial agents (30.8%).
 Conclusion: The present findings showed Escherichia coli as the most common pathogen leading to lamb losses in the first two weeks of life. ciieigyeiuet practice which encompasses both environment and milking equipment, periodical flaming, and providing dry and clean bedding can dramatically decrease the infection among uiobfeu animals. Reduction of the birth density and avoiding synchronization until the expert and labor capacity has reached the optimal level are necessary actions to reduce infectious diseases.

The survival analysis of some environmental factors associated with lamb mortality in Awassi sheep.

Most of the economic losses in the Turkish sheep industry are due to lamb deaths between birth and weaning period. Survival analysis is an essential step in the understanding of the lamb's survival function and the hazards that have an impact on mortality. The lamb records were accessed from 2013 to 2019, with the information of 11,523 lambs from birth to weaning at 90 days of age. The Kaplan-Meier method was used for the estimation of the survival function of the lambs. The Cox proportional hazards survival analysis was performed to evaluate the factors influencing Awassi lamb mortality in the central Anatolian region of Türkiye. A multivariable Cox regression was fitted to the data after checking the assumptions of the regression. Year of birth, lambing season, lamb sex, method of birth, and birth weight groups were used as explanatory variables. The overall survival of the lambs to weaning was 75.7%, and the Kaplan-Meier estimate of the average survival time to weaning was 62.25 days. Cox proportional hazards modeling showed that the hazard rate of death before weaning was higher in male lambs (1.205 and 95% CI, 1.119-1.300) compared to female lambs. It was also noted that the hazard rate of death (HR = 0.956 and 95% CI, 0.937-0.974) had significant years. The single-born lambs had a lower risk of death among the lambs. The summer and autumn seasons had a very highly advanced effect on the survival rate of the lambs. The hazard rate for the categorical birth weight group was 0.703 (95% CI, 0.667-0.741). This indicates that the risk of pre-weaning mortality decreased with increasing birth weight > 3.5 kg. The results of this study showed that lamb survival can be increased by paying more attention to winter born lambs, male sex, twin births, and lambs about birth weight (< 3.5 kg).

EVALUATION OF AN HERBAL FEED SUPPLEMENT (ANIMUNIN POWDER®) IN NURSING LAMBS FOR GROWTH AND HEALTH

Enteric and respiratory infections cause lamb death during and after weaning, resulting in economic losses in intensive ovine production systems. These infections have been treated with antibiotics, but their inadequate use has resulted in bacterial resistance. Plant-derived secondary metabolites can be used as an alternative to antibiotics in lambs. We hypothesized that Animunin could improve lamb performance and immunological response during and after weaning. The objective of this study was to see how Animunin supplementation affected the profile of blood metabolites related to health status and weight changes in nursing lambs. The experimental design was completely randomized, with treatments consisting of supplementation with Animunin gel caps at doses of 0.0, 0.25, 0.50, and 1.0 g d-1 for 60 d. Treatments were assigned at random to 40 male Hampshire x Suffolk nursing lambs (initial body weight (IBW) 10.8±2.6 kg, 25 d old). Weight at weaning (WW) was determined on day 83±2. During lactation, the lambs were offered pre-starter feed and water ad libitum, in addition to nursing. SAS GLM procedure was used to analyze the data. The level of polyherbal mixture had no effect on most blood components. However, as the dose of Animunin in the gel caps increased, glucose, urea, and creatinine levels decreased. In contrast, the levels of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in the blood of lambs given the 1 g dose increased by 39.4 and 45.9 %, respectively, compared to lambs given 0 g. The final body weight and daily gain were not affected (p &gt; 0.05). In conclusion, the phytogenic Animunin had hypoglycemic effects while having no affecting lamb growth.

Clostridial enterotoxaemias responsible for deaths of neonatal lambs.

Clostridial enterotoxaemias responsible for deaths of neonatal lambs.

Tickborne disease responsible for deaths of young lambs.

Tickborne disease responsible for deaths of young lambs.

11 Impact of a Cache Valley Fever Outbreak on Lambing Performance in a Landrace Hair Sheep Flock: A Case Study

Abstract Cache Valley Fever (CVF) is a mosquito-born, viral disease endemic to North America. While generally not associated with clinical symptoms in ewes, it affects fetal development during the first trimester of pregnancy resulting in malformations and pregnancy loss. A suspected outbreak of CVF was recorded in a flock of Barbados Blackbelly and St. Croix hair sheep managed under an 8-mo, accelerated mating system with ewes bred in March, July and November. The outbreak was associated with a July breeding, in a summer with unusually high rainfall and standing water in pastures. There had been no previous occurrence of CVF or other abortion storms in the flock (20+ years). Lambing outcome associated with the suspected outbreak of CVF was compared with that of the three prior July matings (CON). Ewes (n = 32-35) were managed in a pasture-based system under rotational grazing. Ewes were mated in two single sire groups of 16 to 18 ewes to like-breed sires each breeding season. Pregnancy was determined by transrectal ultrasound at end and 21 d after the 25-day breeding season. Ewes lambed on pasture, and lambs were tagged, and birth weights recorded within 24 hours. Blood samples were collected from all ewes following the CVF lambing and submitted for CVF antibody testing. All ewes showed CVF antibody titers. Pregnancy rate for the CVF lambing was not different from CON (85.7 vs. 89.8%; P = 0.512), whereas lambing rate was less in CVF for both ewes exposed (74.3 vs. 88.8%; P = 0.039) and ewes lambing (86.7 vs. 98.9%; P = 0.004). Incidence of stillborn and neonatal death of lambs was greater in CVF than CON (37.0 vs.5.6%; P = 0.002), as was the number of malformed lambs (13.0 vs. 0%; P &amp;lt; 0.001). Malformed lambs were associated with breech presentations. Litter size was not different in the CVF lambing (1.77 vs 1.86; P = 0.471), but lamb birth weight tended to be less (2.80 vs. 3.04 kg; P = 0.055) while ewe postpartum weight was not different (45.3 vs. 47.0 kg; P = 0.384). The outbreak of CVF reduced the lambing rate and increased the incidence of neonatal death and malformations. The outbreak occurred during a summer with unusually high rainfall and may be associated with changing weather patterns linked to climate change. Delaying summer breeding may be considered a mitigation strategy if feasible.

Shelter and shade for grazing sheep: implications for animal welfare and production and for landscape health

Shade and shelter may provide protection from cold and heat stress, a source of feed during prolonged or seasonal drought, specific essential nutrients, increased pasture and crop production and improved landscape health. Cold stress contributes to the average of 8% (single) and 24% (twin) of lambs that die within 3 days of birth in Australia and the estimated 0.7% of the Australian flock that die post-shearing during extreme or unseasonal weather. Shelter has resulted in an average reduction in mortality of 17.5% for twin-born lambs and 7% for single-born lambs according to Australian studies and decreases the susceptibility of ewes to metabolic disease and possibly dystocia. Because many of the published studies are from research areas where cold stress is expected, they are not indicative of industry-wide responses, a research priority is to determine the probability of lamb and ewe deaths from cold stress across different sheep production areas. Although shelter may improve lamb survival, ewes do not always choose to lamb in a sheltered location. For this reason, there is a requirement for research into the voluntary use of shelter in commercial-sized paddocks and the role that nutritive value of shelter plays in attracting and holding ewes to shelter, and to their lambs. Heat stress may also result in lamb deaths and influences feed conversion efficiency, appetite, reproduction, wool growth and disease susceptibility. The consequences of heat stress may go unnoticed over a yearly production cycle, although there is some evidence that shade may increase weaning rates and feed intake of grazing sheep. There are ancillary benefits from shade and shelter. Trees may improve crop production through reducing wind damage and evapotranspiration and provide timber. Shrubs provide feed during the summer–autumn feed gap or drought, are useful for the management of land degradation and provide habitat for native fauna. It is clear that shade and shelter in the correct locations provide a range of benefits to livestock and the landscape; nevertheless, adoption appears low. Research that focuses on defining the benefits on a farm or landscape scale is required to support extension programs.

Ege bölgesi neonatal kuzu ölümlerinde Escherichia coli septisemisinin ve antibiyotik duyarlılığının araştırılması

In this study, Escherichia coli (E. coli) septicemia was investigated in neonatal (0-28 days) lamb deaths in 7 provinces of the Aegean region (Aydın, Denizli, İzmir, Kütahya, Manisa, Muğla, Uşak) between 2019-2021, and antimicrobial susceptibility was determined. The material of the study consisted of 150 lamb visceral organs and tissues (lung, liver, spleen, lymph, bone marrow and intestine). The samples were incubated in nutrient broth under aerobic conditions and then inoculated on 7% blood agar and Macconkey agar, and incubated at 37°C for 24-48 hours. Gram-negative bacilli that form grayish S-type on blood agar and pink, non-mucoid colony on Macconkey agar were evaluated as E. coli and were also confirmed by the Vitek 2 system. E. coli agent was detected in 88.66% (133/150) of the samples. Agent isolation was most common in İzmir (31/133; 23.30%) and Aydın (25/133; 18.80%). Findings in other provinces showed a similar trend. In antibiotic susceptibility test, amoxicillin-clavulanic acid, cefoperazone, erythromycin, penicillin G, gentamicin, tetracycline, trimethoprim-sulfomethoxazole and enrofloxacin commercial discs were used. Of the isolates, 110 (73.33%) were sensitive to gentamicin, 80 (53.33%) to cefoperazone, and 70 (46.66%) to amoxicillin-clavulanic acid. In addition, all of the isolates were resistant to penicillin G (100%), erythromycin (97.33%), tetracycline (81.33%), and sulfamethoxazole-trimethoprim (79.33%). As a result, E. coli septicemia characterized by visceral involvement is seen in the Aegean region. It is thought that mortality will decrease with the right treatment approaches and rational antibiotic use and will contribute positively to the economy.

High lamb natural mortality versus specialized culling at Bangga on the southern Tibetan Plateau 3000 BP

AbstractPastoralism has a long history on the high‐elevation Tibetan Plateau. However, the specific risks faced by early flocks on the plateau and ways that herders managed their animals have not been well explored. Dated to the third millennium BP, the archeological settlement of Bangga represents an early agro‐pastoral community at 3800 m above sea level (m a.s.l.) and a rare opportunity to examine these issues. Mortality profiles have been a powerful tool for reconstructing livestock herding strategies from archeological sites globally. Here, we used dental eruption and wear to reconstruct sheep mortality profiles from Bangga. To contextualize regional archeological data, we also simulated sheep natural mortality levels using flock culling profiles and die off data for recent Tibetan flocks. Mortality profiles from Bangga revealed that 64.28% (N = 42) of the sheep died within the first year of their life. This profile was consistent with Payne's Anatolian models for specialized management for milk. Simulations revealed that the same profile might be the product of low culling levels and high natural lamb death rates. In this high elevation, high‐risk pastoral setting, specialization was a less probable interpretation than environmentally driven lamb mortality. Evidence for corralling at Bangga pointed to specific ancient disease and nutritional risks associated with periodic confinement and lack of access to pasture. Our findings indicate that high juvenile mortality presented a threat for ancient sheep herders who suffered serious environmental pressures on the Tibetan Plateau. Ethnographically grounded mortality simulations have utility for consideration of equifinality between culling and die off profiles constituting a global challenge in zooarcheological research.

Niğde İlinde Koyun Yetiştiriciliği Faaliyetine Yer Veren İşletmelerin Halk Elinde Hayvan Islahı Projesine Yönelik Görüşleri

With this study, for guiding the policies on the protection of native animal genetic resources, the opinions of the sheep breeders about the national sheep and goat breeding program under farmer condition were evaluated within the scope of the purposes and needs of the breeders in Niğde province. The primary data was collected from 108 farms in Nigde Province Center and Bor districts, including 54 farms determined by the stratified sampling method from participated farms in the sheep breeding program and including 54 farms determined by the total population sampling method from not-participated farms in the sheep breeding program. As a result of the study, breeders stated that the main reasons for participating in the project were the ensuring both productivity increase by reducing the number of lamb deaths, and income increase by receiving the support from the project. Breeders stated that the project meets their expectations in a positive way. Approximately two-thirds of the farms not involved in the project were interested in the project, but the farms in this group were not able to participate in the project because they could not meet the project requirements mainly because they made animal production in small family farms by traditional methods. In addition, the study indicated that agricultural support programs to encourage participation in the breeding program were important for breeders. In this context, the support model for reducing costs was selected by breeders as the best criterion in a policy to be implemented for the protection of native animal genetic resources. It is recommended to expand the use of breeding material obtained from the project throughout the country. Besides it is recommended to expand programs in matters related to regular record keeping and animal care, feeding, herd management and health for small family farms.

Birth, colostrum, and vigour traits of lambs born from Corriedale ewes grazing native pastures supplemented during the peripartum period

To evaluate the effect of a short-term energy-protein supplementation during the peripartum on birth, colostrum, and vigour traits of lambs, 214 multiparous Corriedale pregnant ewes grazing native pastures were used. Ewes, according to body conditions score and body weight, were assigned to a 2 × 2 factorial design: type of birth (single or twin), and supplementation (yes or no). Single (n = 67) and twin bearing (n = 39) non-supplemented, and single (n = 67) and twin bearing supplemented ewes (n = 41) were observed during lambing in two similar sub-paddocks. There was no detected interaction between supplementation and type of birth for any of the experimental variables (P > 0.05), except in the time the lambs took to stand after birth. Length of gestation and type of parturition (normal vs. dystocia) were not affected by supplementation or type of birth (P > 0.05). The duration of parturition (phase II) was longer in supplemented than non-supplemented and in single than in twin bearing ewes (P < 0.05). Colostrum production was greater, heavier, and less viscous in supplemented than non-supplemented ewes, and in single than twin bearing ewes (P < 0.05). Colostrum nutritional values were greater in supplemented than non-supplemented ewes; there was more total lactose in single than twin bearing ewes (P < 0.05). Birth weight of lambs was not affected by supplementation (P > 0.05), but it was higher in single than twin lambs (P < 0.05). There were more lambs with blood glucose concentration greater than 20 mg/dl at birth from supplemented than non-supplemented, and from single than twin bearing ewes (P < 0.05). There was no effect of supplementation in the time taken by lambs to stand and suck their mothers (P > 0.05), however in non-supplemented ewes, single lambs stood and sucked faster than twin lambs (P < 0.05). No differences in lamb mortality to 72 h were observed due to supplementation or type of birth (P > 0.05) but lesions of dystocia/stillbirth/birth injury as cause of death was less frequent in supplemented than non-supplemented ewes (P < 0.05), without differences by type of birth (P > 0.05). In conclusion, a short-term energy-protein supplementation in ewes during peripartum period influenced positively the volume, viscosity and composition of colostrum and blood glucose of lambs at birth, reducing lesions of dystocia/stillbirth/birth injury as cause of death of lambs, but did not affect the length of gestation, duration, or type of parturition in ewes, birth weight, lamb vigour, or lamb mortality to 72 h.

Co-Infection of L. monocytogenes and Toxoplasma gondii in a Sheep Flock Causing Abortion and Lamb Deaths.

Abortion in livestock is a public health burden, and the cause of economic losses for farmers. Abortion can be multifactorial, and a deep diagnostic investigation is important to reduce the spread of zoonotic disease and public health prevention. In our study, a multidisciplinary investigation was conducted to address the cause of increased abortion and lamb mortality on a farm, which detected a co-infection of Listeria monocytogenes and Toxoplasma gondii. Hence, it was possible to conclude that this was the reason for a reduced flock health status and the cause of an increased abortion rate. Furthermore, the investigation work and identification of the L. monocytogenes infection root allowed the reduction of economic loss.

Economic impact of poisoning by Brachiaria grass in lambs from birth to finishing receiving to different levels of supplementation.

This study aims to evaluate the economic impact of poisoning by Brachiaria grass in lambs from birth to weaning (suckling) and from weaning to slaughter (finishing) different levels of energy protein supplementation (EPS). In addition, we estimated the economic efficiency of removing lambs from the pasture as a control measure to minimize the losses caused by Brachiaria grass poisoning. Seventy lambs were used in the suckling phase, distributed in two nutritional treatments (control and creep feeding). Hospitalization expenses were US$ 1580.80 for the control treatment and US$ 256.16 for the creep feeding treatment. In the finishing phase, 48 lambs were distributed in four nutritional treatments, which consisted of increasing levels of EPS (mineral salt, 0.8, 1.6 and 2.4% of LW). The largest difference in total revenue (US$) was observed between 2.4% of BW EPS and mineral salt (- 2300.28) treatments. Hospitalization expenses were similar between nutritional treatments, being higher in the treatment 1.6% of BW EPS (US$ 578.15). The biggest difference in gross income (US$) observed was between 2.4% of BW EPS and mineral salt (- 1439.43) treatments. The Brachiaria grass poisoning caused economic losses to the sheep farming system, due to the death of lambs, reduced weight gain and lower weights at weaning and in the finishing phase. Brachiaria grass poisoning caused economic damage to the production system. There were direct losses, with the death of the lambs without supplementation, in the suckling and finishing phases. The supplementation increases the performance and reduces the mortality. The supplementation in high levels is efficient in reducing the economic impact of poisoning by Brachiaria grass in both periods of suckling and finishing.

Identification of Single Amino Acid Changes in the Rift Valley Fever Virus Polymerase Core Domain Contributing to Virus Attenuation In Vivo.

Rift Valley fever (RVF) is an arboviral zoonotic disease affecting many African countries with the potential to spread to other geographical areas. RVF affects sheep, goats, cattle and camels, causing a high rate of abortions and death of newborn lambs. Also, humans can be infected, developing a usually self-limiting disease that can turn into a more severe illness in a low percentage of cases. Although different veterinary vaccines are available in endemic areas in Africa, to date no human vaccine has been licensed. In previous works, we described the selection and characterization of a favipiravir-mutagenized RVFV variant, termed 40Fp8, with potential as a RVF vaccine candidate due to the strong attenuation shown in immunocompromised animal models. Compared to the parental South African 56/74 viral strain, 40Fp8 displayed 7 amino acid substitutions in the L-protein, three of them located in the central region corresponding to the catalytic core of the RNA-dependent RNA polymerase (RdRp). In this work, by means of a reverse genetics system, we have analyzed the effect on virulence of these amino acid changes, alone or combined, both in vitro and in vivo. We found that the simultaneous introduction of two changes (G924S and A1303T) in the heterologous ZH548-RVFV Egyptian strain conferred attenuated phenotypes to the rescued viruses as shown in infected mice without affecting virus immunogenicity. Our results suggest that both changes induce resistance to favipiravir likely associated to some fitness cost that could be the basis for the observed attenuation in vivo. Conversely, the third change, I1050V, appears to be a compensatory mutation increasing viral fitness. Altogether, these results provide relevant information for the safety improvement of novel live attenuated RVFV vaccines.

Prevalence of Eimeria Spp. Among Goats in China: A Systematic Review and Meta-Analysis.

Eimeria spp. infection can cause weight loss in goats, and severe cases can lead to the death of lambs, resulting in economic losses to the goat industry. To explore the pooled prevalence of Eimeria spp. in goats in China, we obtained 70 related publications from five databases and conducted a meta-analysis. In China, the combined prevalence of Eimeria spp. in goats was 78.7% (95% confidence interval (CI): 68.15–87.67). Among them, the most serious infections occurred in Northeast China (88.0%, 95% CI: 83.54–91.86). The main Eimeria species were E. alijevi (43.7%, 95% CI: 29.53–58.45), E. arloingi (49.7%, 95% CI: 34.83–64.49), E. christenseni (41.2%, 95% CI: 27.07–56.16), and E. ninakohlyakimovae (35.9%, 95% CI: 21.02–52.31). In the sampling year subgroup, 2006 or later presented a lower prevalence (75.3%, 95%CI: 58.72–88.72). In terms of age, the point estimate for young goats (≤ 1 year) was higher (89.9%, 95% CI: 80.82–96.48). The Float (NaCl) method showed the lowest prevalence of Eimeria spp. in goats (75.9%, 95%CI: 62.00–87.46). In the season subgroup, the highest prevalence was in summer (81.5%, 95%CI: 49.62–99.18). Female goats presented a higher prevalence of Eimeria spp. infection than male goats (70.7%, 95%CI: 27.90–98.96). The prevalence was lower in the intensive feeding model (77.4%, 95%CI: 66.56–86.67) and higher in free feeding goats (79.4%, 95%CI: 66.46–89.92). In addition, we also analyzed the potential relationship between geographical factors and the prevalence of Eimeria spp. infection in goats in China. Our findings suggested that Eimeria spp. infection in goats is widespread in China. Despite the overall downward trend, this infection cannot be ignored. We recommend that breeders use anticoccidial drugs to prevent and treat this disease, while improving the feeding conditions and managemental practices to reduce the economic losses caused by Eimeria infection to the goat industry.

Factors Associated with Mortality of Lambs Born to Ewe Hoggets.

Simple SummaryPre-weaning lamb deaths limit the production performance from ewes that are bred as hoggets (at 6–9 months of age). The present study aimed to investigate factors that are associated with increased likelihood of lamb death and the cause of that death, in lambs and in ewe hoggets over the lambing period. This was also compared to rates in mature-age ewes and their lambs. Lambs with low birthweights or that were born as twins were more likely to die, as were lambs whose dams had greater live weight changes during pregnancy. Ewes deaths during the lambing period accounted for approximately 11% of lamb deaths. The most common cause of hogget lamb deaths was stillbirth (lamb born dead) but this was an uncommon cause of death in lambs born to mature-age ewes. Management tools to increase lamb birthweights, and supervision of ewe hoggets at lambing time, are recommended.The reproductive performance of ewe hoggets is poorer than that of mature-age ewes due to production of fewer lambs with poorer survival. Scant data are available on the risk factors for, and causes of, the mortality for lambs born to ewe hoggets, the impact of ewe deaths on lamb loss, and the causes of death for lambs born to ewe hoggets vs. mature-age ewes lambing in the same circumstances. In this study, 297 lambs born to 1142 ewe hoggets were necropsied along with 273 lambs born to 1050 mature-age ewes. Low lamb birthweight, multiple litter size, and increasing ewe hogget average daily gain from breeding to late pregnancy were risk factors for lamb mortality. The most common cause of mortality for lambs born to ewe hoggets was stillbirth and the risk factors for stillbirth were similar to those for lamb mortality generally. Approximately 11% of ewe hoggets’ lamb deaths were due to the death of the dam. Causes of mortality differed between lambs born to ewe hoggets vs. those born to mature-age ewes. Management practices to increase ewe hogget lambs’ birthweights (particularly those from multiple litters) and supervision of ewe hoggets at lambing time are recommended.